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Sample records for cold trapped ions

  1. REVIEW: Quantum simulations with cold trapped ions

    NASA Astrophysics Data System (ADS)

    Johanning, Michael; Varón, Andrés F.; Wunderlich, Christof

    2009-08-01

    The control of internal and motional quantum degrees of freedom of laser-cooled trapped ions has been subject to intense theoretical and experimental research for about three decades. In the realm of quantum information science, the ability to deterministically prepare and measure quantum states of trapped ions is unprecedented. This expertise may be employed to investigate physical models conceived to describe systems that are not directly accessible for experimental investigations. Here, we give an overview of current theoretical proposals and experiments for such quantum simulations with trapped ions. This includes various spin models (e.g. the quantum transverse Ising model or a neural network), the Bose-Hubbard Hamiltonian, the Frenkel-Kontorova model, and quantum fields and relativistic effects.

  2. Quantum simulations with cold trapped ions

    NASA Astrophysics Data System (ADS)

    Blatt, Rainer

    2016-05-01

    The quantum toolbox of the Innsbruck ion-trap quantum computer is applied to simulate the dynamics and to investigate the propagation of entanglement in a quantum many-body system represented by long chains of trapped-ion qubits. Quantum dynamics can be described by particle-like carriers of information that emerge in the collective behavior of the underlying system, the so-called quasiparticles. These elementary excitations are predicted to distribute quantum information in a fashion determined by the system's interactions. First, we observe the entanglement distributed by quasiparticles as they trace out light-cone-like wavefronts. Second, using the ability to tune the interaction range in our system, we observe information propagation in an experimental regime where the effective-lightcone picture does not apply. Moreover, a spectroscopic technique is presented to study artificial quantum matter and use it for characterizing quasiparticles in a many-body system of trapped atomic ions. Our approach is to excite combinations of the system's fundamental quasiparticle eigenmodes, given by delocalized spin waves. By observing the dynamical response to superpositions of such eigenmodes, we extract the system dispersion relation, magnetic order, and even detect signatures of quasiparticle interactions. In the second part of the talk, it will be shown how strings of trapped ions can be used for quantum simulations of a lattice gauge field theory. As an example, we map the real-time evolution of the Schwinger mechanism to a string of trapped ions in a few-qubit quantum computer, simulating the spontaneous creation of electron-positron pairs.

  3. Vibrational Spectroscopy on Trapped Cold Molecular Ions

    NASA Astrophysics Data System (ADS)

    Khanyile, Ncamiso B.; Brown, Kenneth R.

    2014-06-01

    We perform vibrational spectroscopy on the V0←10 overtone of a trapped and sympathetically cooled CaH+ molecular ion using a resonance enhanced two photon dissociation scheme. Our experiments are motivated by theoretical work that proposes comparing the vibrational overtones of CaH^+ with electronic transitions in atoms to detect possible time variation of in the mass ratio of the proton to electron. Due to the nonexistence of experimental data of the transition, we start the search with a broadband femtosecond Ti:Saph laser guided by theoretical calculations. Once the vibrational transition has been identified, we will move to CW lasers to perform rotationally resolved spectroscopy. M. Kajita and Y. Moriwaki, J. Phys. B. At. Mol. Opt.Phys., 42,154022(2009) Private communication

  4. Vibrational Cooling in A Cold Ion Trap: Vibrationally Resolved Photoelectron Spectroscopy of Cold C60- Anions

    SciTech Connect

    Wang, Xue B.; Woo, Hin-koon; Wang, Lai S.

    2005-08-01

    We demonstrate vibrational cooling of anions via collisions with a background gas in an ion trap attached to a cryogenically controlled cold head (10 ? 400 K). Photoelectron spectra of vibrationally cold C60- anions, produced by electrospray ionization and cooled in the cold ion trap, have been obtained. Relative to spectra taken at room temperature, vibrational hot bands are completely eliminated, yielding well resolved vibrational structures and a more accurate electron affinity for neutral C60. The electron affinity of C60 is measured to be 2.683 ? 0.008 eV. The cold spectra reveal complicated vibrational structures for the transition to the C60 ground state due to the Jahn-Teller effect in the ground state of C60-. Vibrational excitations in the two Ag modes and eight Hg modes are observed, providing ideal data to assess the vibronic couplings in C60-.

  5. COLD TRAPS

    DOEpatents

    Thompson, W.I.

    1958-09-30

    A cold trap is presented for removing a condensable component from a gas mixture by cooling. It consists of a shell, the exterior surface of which is chilled by a refrigerant, and conductive fins welded inside the shell to condense the gas, and distribute the condensate evenly throughout the length of the trap, so that the trap may function until it becomes completely filled with the condensed solid. The contents may then be removed as either a gas or as a liquid by heating the trap. This device has particuinr use as a means for removing uranium hexafluoride from the gaseous diffusion separation process during equipment breakdown and repair periods.

  6. COLD TRAP

    DOEpatents

    Milleron, N.

    1963-03-12

    An improved linear-flow cold trap is designed for highvacuum applications such as mitigating back migration of diffusion pump oil moiecules. A central pot of liquid nitrogen is nested within and supported by a surrounding, vertical, helical coil of metai sheet, all enveloped by a larger, upright, cylindrical, vacuum vessel. The vertical interstices between successive turns of the coil afford lineal, axial, high-vacuum passages between open mouths at top and bottom of said vessel, while the coil, being cold by virtue of thermal contact of its innermost turn with the nitrogen pot, affords expansive proximate condensation surfaces. (AEC)

  7. Chemical reactions between cold trapped Ba+ ions and neutral molecules in the gas phase

    NASA Astrophysics Data System (ADS)

    Roth, B.; Offenberg, D.; Zhang, C. B.; Schiller, S.

    2008-10-01

    Using a laser-cooled ion trapping apparatus, we have investigated laser-induced chemical reactions between cold trapped Ba+ ions and several neutral molecular gases at room temperature, O2 , CO2 , and N2O , leading to the production of cold trapped (≈20mK) BaO+ ions. The BaO+ ions were converted back to Ba+ ions via reaction with room-temperature CO. Reaction rates were determined by employing molecular dynamics simulations. The cold mixed-species ion ensembles produced were used for studying the efficiency of sympathetic cooling, by variation of the ratio of laser-cooled to sympathetically cooled ion numbers. In one extreme case, 20 laser-cooled Ba+138 ions were capable of maintaining the translational temperature of 120 sympathetically cooled barium isotopes (Ba+135-137) and 430 Ba16138O+ molecules at approximately 25mK .

  8. Formation of molecular ions by radiative association of cold trapped atoms and ions

    NASA Astrophysics Data System (ADS)

    Dulieu, Olivier; da Silva, Humberto, Jr.; Aymar, Mireille; Raoult, Maurice

    2015-05-01

    Radiative emission during cold collisions between trapped laser-cooled Rb atoms and alkaline-earth ions (Ca+ , Sr+ , Ba+) and Yb+ are studied theoretically, using accurate effective-core-potential based quantum chemistry calculations of potential energy curves and transition dipole moments of the related molecular ions. Radiative association of molecular ions is predicted to occur for all systems with a cross section two to ten times larger than the radiative charge transfer one. Partial and total rate constants are also calculated and compared to available experiments. Narrow shape resonances are expected, which could be detectable at low temperature with an experimental resolution at the limit of the present standards. Vibrational distributions show that the final molecular ions are not created in their ground state level. Supported by the Marie-Curie ITN ``COMIQ: Cold Molecular Ions at the Quantum limit'' of the EU (#607491).

  9. Superstatistical velocity distributions of cold trapped ions in molecular-dynamics simulations

    NASA Astrophysics Data System (ADS)

    Rouse, I.; Willitsch, S.

    2015-11-01

    We present a realistic molecular-dynamics treatment of laser-cooled ions in radio-frequency ion traps which avoids previously made simplifications such as modeling laser cooling as a friction force and combining individual heating mechanisms into a single effective heating force. Based on this implementation, we show that infrequent energetic collisions of single ions with background gas molecules lead to pronounced heating of the entire ion ensemble and a time-varying secular ensemble temperature, which manifests itself in a superstatistical time-averaged velocity distribution of the ions. The effect of this finding on the experimental determination of ion temperatures and rate constants for cold chemical reactions is discussed.

  10. Liquid metal cold trap

    DOEpatents

    Hundal, Rolv

    1976-01-01

    A cold trap assembly for removing impurities from a liquid metal being provided with a hole between the incoming impure liquid metal and purified outgoing liquid metal which acts as a continuous bleed means and thus prevents the accumulation of cover gases within the cold trap assembly.

  11. IR-induced conformational isomerization of a helical peptide in a cold ion trap.

    PubMed

    Seaiby, Caroline; Zabuga, Aleksandra V; Svendsen, Annette; Rizzo, Thomas R

    2016-01-01

    In this work, we use laser-induced population transfer techniques to study the conformational isomerization of a helical peptide, Ac-Phe-(Ala)5-LysH(+), in a cold ion trap. In one scheme, called IR-UV hole-filling spectroscopy, a single conformation is selectively excited with an IR pump laser via a distinct NH stretch vibration. After giving the vibrationally excited ions sufficient time to isomerize and re-cool in the trap, the new conformational redistribution is detected by UV photofragment spectroscopy. While we clearly observe a redistribution of the conformer populations due to isomerization, only those conformations that initially have population participate in this redistribution-we do not form conformers that were not initially present in the trap. In a second scheme, called IR-induced population transfer spectroscopy, we determine the fractional populations of the four stable conformations of Ac-Phe-(Ala)5-LysH(+) by scanning the IR laser while selectively detecting a specific conformation using UV photofragment spectroscopy. PMID:26747803

  12. Radial cold trap

    DOEpatents

    Grundy, Brian R.

    1981-01-01

    The radial cold trap comprises a housing having a plurality of mesh bands disposed therein. The mesh bands comprise concentrically arranged bands of mesh with the mesh specific surface area of each band increasing from the outermost mesh band to the innermost mesh band. An inlet nozzle is attached to the outside section of the housing while an outlet nozzle is attached to the inner portion of the housing so as to be concentrically connected to the innermost mesh band. An inlet baffle having orifices therein may be disposed around the outermost mesh band and within the housing for directing the flow of the fluid from the inlet nozzle to the outermost mesh band in a uniform manner. The flow of fluid passes through each consecutive mesh band and into the outlet nozzle. The circular pattern of the symmetrically arranged mesh packing allows for better utilization of the entire cold trap volume.

  13. Radial cold trap

    DOEpatents

    Grundy, B.R.

    1981-09-29

    The radial cold trap comprises a housing having a plurality of mesh bands disposed therein. The mesh bands comprise concentrically arranged bands of mesh with the mesh specific surface area of each band increasing from the outermost mesh band to the innermost mesh band. An inlet nozzle is attached to the outside section of the housing while an outlet nozzle is attached to the inner portion of the housing so as to be concentrically connected to the innermost mesh band. An inlet baffle having orifices therein may be disposed around the outermost mesh band and within the housing for directing the flow of the fluid from the inlet nozzle to the outermost mesh band in a uniform manner. The flow of fluid passes through each consecutive mesh band and into the outlet nozzle. The circular pattern of the symmetrically arranged mesh packing allows for better utilization of the entire cold trap volume. 2 figs.

  14. Dynamics of a Cold Trapped Ion in a Bose-Einstein Condensate

    SciTech Connect

    Schmid, Stefan; Haerter, Arne; Denschlag, Johannes Hecker

    2010-09-24

    We investigate the interaction of a laser-cooled trapped ion (Ba{sup +} or Rb{sup +}) with an optically confined {sup 87}Rb Bose-Einstein condensate. The system features interesting dynamics of the ion and the atom cloud as determined by their collisions and their motion in their respective traps. Elastic as well as inelastic processes are observed and their respective cross sections are determined. We demonstrate that a single ion can be used to probe the density profile of an ultracold atom cloud.

  15. First principle simulations of phonons and thermal excitations of ultra-cold non-neutral ion plasmas in Penning traps

    NASA Astrophysics Data System (ADS)

    Meiser, Dominic; Sawyer, Brian C.; Britton, Joesph W.; Bollinger, John J.

    2013-10-01

    Ultra-cold ions in Penning traps are a powerful platform for research in strongly correlated plasmas, quantum information, quantum metrology, and simulation of complex many-body problems of condensed matter theory. Thermal excitations of the ion crystals play a central role in these experiments. On the one hand, the motion associated with them is a limiting factor for the performance of current experiments. Better cooling of the ions could pave the way to new experiments. On the other hand, phonons are instrumental in some of the quantum simulation experiments because they allow one to engineer specific effective interactions between the spins of different ions. To better understand the phonons and thermal excitations in ultra-cold ion crystals we have carried out first principles molecular dynamics simulations. These simulations include a microscopic model for the laser cooling in addition to the cyclotron motion, trapping potentials, and Coulomb interactions between pairs of ions. We present results from these simulations on the stationary properties of planar ion crystals, phonon spectra and phonon mode structures, temperature of the phonon modes, and the dynamics of rearrangements of ions in the crystal.

  16. Trapping cold molecular hydrogen.

    PubMed

    Seiler, Ch; Hogan, S D; Merkt, F

    2011-11-14

    Translationally cold H(2) molecules excited to non-penetrating |M(J)| = 3 Rydberg states of principal quantum number in the range 21-37 have been decelerated and trapped using time-dependent inhomogeneous electric fields. The |M(J)| = 3 Rydberg states were prepared from the X (1)Σ(+)(u)(v = 0, J = 0) ground state using a resonant three-photon excitation sequence via the B (1)Σ(+)(u)(v = 3, J = 1) and I (1)Π(g) (v = 0, J = 2) intermediate states and circularly polarized laser radiation. The circular polarization of the vacuum ultraviolet radiation used for the B ← X transition was generated by resonance-enhanced four-wave mixing in xenon and the degree of circular polarization was determined to be 96%. To analyse the deceleration and trapping experiments, the Stark effect in Rydberg states of molecular hydrogen was calculated using a matrix diagonalization procedure similar to that presented by Yamakita et al., J. Chem. Phys., 2004, 121, 1419. Particular attention was given to the prediction of zero-field positions of low-l states and of avoided crossings between Rydberg-Stark states with different values of |M(J)|. The calculated Stark maps and probabilities for diabatic traversal of the avoided crossings were used as input to Monte-Carlo particle-trajectory simulations. These simulations provide a quantitatively satisfactory description of the experimental data and demonstrate that particle loss caused by adiabatic traversals of avoided crossings between adjacent |M(J)| = 3 Stark states of H(2) is small at principal quantum numbers beyond n = 25. The main source of trap losses was found to be from collisional processes. Predissociation following the absorption of blackbody radiation is estimated to be the second most important trap-loss mechanism at room temperature, and trap loss by spontaneous emission is negligible under our experimental conditions. PMID:21818497

  17. Ion Trap Mass Spectrometry

    SciTech Connect

    Eiden, Greg C.

    2005-09-01

    This chapter describes research conducted in a few research groups in the 1990s in which RF quadrupole ion trap mass spectrometers were coupled to a powerful atomic ion source, the inductively coupled plasma used in conventional ICP-MS instruments. Major section titles for this chapter are: RF Quadrupole Ion Traps Features of RF Quadrupole Ion Trap Mass Spectrometers Selective Ion Trapping methods Inductively Coupled Plasma Source Ion Trap Mass Spectrometers

  18. Effect of Coulomb interaction on time of flight of cold antiprotons launched from an ion trap

    NASA Technical Reports Server (NTRS)

    Camp, J. B.; Witteborn, F. C.

    1993-01-01

    Time-of-flight spectra for Maxwell-Boltzman (MB) distributions of antiprotons initially held in an ion trap and detected after being launched through a 50-cm-long shielding drift tube have been calculated. The distributions used are of temperature 0.4-40 K, cubic length 0.003-3.0 cm, and number 10-100 particles. The mutual Coulomb repulsion of the particles causes a reduction in the number of late arrival particles expected from the MB velocity distribution. The Coulomb energy is not equally divided among the particles during the expansion. The energy is transferred preferentially to the outer particles so that the reduction in the number of slow particles is not necessarily large. The reduction factor is found to be greater than unity when the potential energy of the trapped ions is greater than about 5 percent of the ions' kinetic energy and is about 2 for the launch parameters of the Los Alamos antiproton gravity experiment.

  19. Ion trap simulation tools.

    SciTech Connect

    Hamlet, Benjamin Roger

    2009-02-01

    Ion traps present a potential architecture for future quantum computers. These computers are of interest due to their increased power over classical computers stemming from the superposition of states and the resulting capability to simultaneously perform many computations. This paper describes a software application used to prepare and visualize simulations of trapping and maneuvering ions in ion traps.

  20. Microfabricated ion trap array

    DOEpatents

    Blain, Matthew G.; Fleming, James G.

    2006-12-26

    A microfabricated ion trap array, comprising a plurality of ion traps having an inner radius of order one micron, can be fabricated using surface micromachining techniques and materials known to the integrated circuits manufacturing and microelectromechanical systems industries. Micromachining methods enable batch fabrication, reduced manufacturing costs, dimensional and positional precision, and monolithic integration of massive arrays of ion traps with microscale ion generation and detection devices. Massive arraying enables the microscale ion traps to retain the resolution, sensitivity, and mass range advantages necessary for high chemical selectivity. The reduced electrode voltage enables integration of the microfabricated ion trap array with on-chip circuit-based rf operation and detection electronics (i.e., cell phone electronics). Therefore, the full performance advantages of the microfabricated ion trap array can be realized in truly field portable, handheld microanalysis systems.

  1. Cold Strontium Ion Source for Ion Interferometry

    NASA Astrophysics Data System (ADS)

    Jackson, Jarom; Durfee, Dallin

    2015-05-01

    We are working on a cold source of Sr Ions to be used in an ion interferometer. The beam will be generated from a magneto-optical trap (MOT) of Sr atoms by optically ionizing atoms leaking out a carefully prepared hole in the MOT. A single laser cooling on the resonant transition (461 nm) in Sr should be sufficient for trapping, as we've calculated that losses to the atom beam will outweigh losses to dark states. Another laser (405 nm), together with light from the trapping laser, will drive a two photon transition in the atom beam to an autoionizing state. Supported by NSF Award No. 1205736.

  2. Microfabricated cylindrical ion trap

    DOEpatents

    Blain, Matthew G.

    2005-03-22

    A microscale cylindrical ion trap, having an inner radius of order one micron, can be fabricated using surface micromachining techniques and materials known to the integrated circuits manufacturing and microelectromechanical systems industries. Micromachining methods enable batch fabrication, reduced manufacturing costs, dimensional and positional precision, and monolithic integration of massive arrays of ion traps with microscale ion generation and detection devices. Massive arraying enables the microscale cylindrical ion trap to retain the resolution, sensitivity, and mass range advantages necessary for high chemical selectivity. The microscale CIT has a reduced ion mean free path, allowing operation at higher pressures with less expensive and less bulky vacuum pumping system, and with lower battery power than conventional- and miniature-sized ion traps. The reduced electrode voltage enables integration of the microscale cylindrical ion trap with on-chip integrated circuit-based rf operation and detection electronics (i.e., cell phone electronics). Therefore, the full performance advantages of microscale cylindrical ion traps can be realized in truly field portable, handheld microanalysis systems.

  3. Ion trap device

    DOEpatents

    Ibrahim, Yehia M.; Smith, Richard D.

    2016-01-26

    An ion trap device is disclosed. The device includes a series of electrodes that define an ion flow path. A radio frequency (RF) field is applied to the series of electrodes such that each electrode is phase shifted approximately 180 degrees from an adjacent electrode. A DC voltage is superimposed with the RF field to create a DC gradient to drive ions in the direction of the gradient. A second RF field or DC voltage is applied to selectively trap and release the ions from the device. Further, the device may be gridless and utilized at high pressure.

  4. Nonlinear integrable ion traps

    SciTech Connect

    Nagaitsev, S.; Danilov, V.; /SNS Project, Oak Ridge

    2011-10-01

    Quadrupole ion traps can be transformed into nonlinear traps with integrable motion by adding special electrostatic potentials. This can be done with both stationary potentials (electrostatic plus a uniform magnetic field) and with time-dependent electric potentials. These potentials are chosen such that the single particle Hamilton-Jacobi equations of motion are separable in some coordinate systems. The electrostatic potentials have several free adjustable parameters allowing for a quadrupole trap to be transformed into, for example, a double-well or a toroidal-well system. The particle motion remains regular, non-chaotic, integrable in quadratures, and stable for a wide range of parameters. We present two examples of how to realize such a system in case of a time-independent (the Penning trap) as well as a time-dependent (the Paul trap) configuration.

  5. Asymmetric ion trap

    DOEpatents

    Barlow, Stephan E.; Alexander, Michael L.; Follansbee, James C.

    1997-01-01

    An ion trap having two end cap electrodes disposed asymmetrically about a center of a ring electrode. The inner surface of the end cap electrodes are conformed to an asymmetric pair of equipotential lines of the harmonic formed by the application of voltages to the electrodes. The asymmetry of the end cap electrodes allows ejection of charged species through the closer of the two electrodes which in turn allows for simultaneously detecting anions and cations expelled from the ion trap through the use of two detectors charged with opposite polarity.

  6. Ion trap in a semiconductor chip

    NASA Astrophysics Data System (ADS)

    Stick, D.; Hensinger, W. K.; Olmschenk, S.; Madsen, M. J.; Schwab, K.; Monroe, C.

    2006-01-01

    The electromagnetic manipulation of isolated atoms has led to many advances in physics, from laser cooling and Bose-Einstein condensation of cold gases to the precise quantum control of individual atomic ions. Work on miniaturizing electromagnetic traps to the micrometre scale promises even higher levels of control and reliability. Compared with `chip traps' for confining neutral atoms, ion traps with similar dimensions and power dissipation offer much higher confinement forces and allow unparalleled control at the single-atom level. Moreover, ion microtraps are of great interest in the development of miniature mass-spectrometer arrays, compact atomic clocks and, most notably, large-scale quantum information processors. Here we report the operation of a micrometre-scale ion trap, fabricated on a monolithic chip using semiconductor micro-electromechanical systems (MEMS) technology. We confine, laser cool and measure heating of a single 111Cd+ ion in an integrated radiofrequency trap etched from a doped gallium-arsenide heterostructure.

  7. Computing rotational energy transfers of OD-/OH- in collisions with Rb: isotopic effects and inelastic rates at cold ion-trap conditions

    NASA Astrophysics Data System (ADS)

    González-Sánchez, L.; Gianturco, F. A.; Carelli, F.; Wester, R.

    2015-12-01

    We report close-coupling (CC) quantum dynamics calculations for collisional excitation/de-excitation of the lowest four rotational levels of OD- and of OH- interacting with Rb atoms in a cold ion trap. The calculations are carried out over a range of energies capable of yielding the corresponding rates for state-changing events over a rather broad interval of temperatures which cover those reached in earlier cold trap experiments. They involved sympathetic cooling of the molecular anion through a cloud of laser-cooled Rb atoms, an experiment which is currently being run again through a Heidelberg-Innsbruck collaboration. The significance of isotopic effects is analysed by comparing both systems and the range of temperatures examined in the calculations is extended up to 400 K, starting from a few mK. Both cross sections and rates are found to be markedly larger than in the case of OD-/OH- interacting the He atoms under the same conditions, and the isotopic effects are also seen to be rather significant at the energies examined in the present study. Such findings are discussed in the light of the observed trap losses of molecular anions.

  8. Cold atoms in videotape micro-traps

    NASA Astrophysics Data System (ADS)

    Sinclair, C. D. J.; Retter, J. A.; Curtis, E. A.; Hall, B. V.; Llorente Garcia, I.; Eriksson, S.; Sauer, B. E.; Hinds, E. A.

    2005-08-01

    We describe an array of microscopic atom traps formed by a pattern of magnetisation on a piece of videotape. We describe the way in which cold atoms are loaded into one of these micro-traps and how the trapped atom cloud is used to explore the properties of the trap. Evaporative cooling in the micro-trap down to a temperature of 1~μK allows us to probe the smoothness of the trapping potential and reveals some inhomogeneity produced by the magnetic film. We discuss future prospects for atom chips based on microscopic permanent-magnet structures.

  9. Modeling the Stability of Volatile Deposits in Lunar Cold Traps

    NASA Technical Reports Server (NTRS)

    Crider, D. H.; Vondrak, R. R.

    2002-01-01

    There are several mechanisms acting at the cold traps that can alter the inventory of volatiles there. Primarily, the lunar surface is bombarded by meteoroids which impact, melt, process, and redistribute the regolith. Further, solar wind and magnetospheric ion fluxes are allowed limited access onto the regions in permanent shadow. Also, although cold traps are in the permanent shadow of the Sun, there is a small flux of radiation incident on the regions from interstellar sources. We investigate the effects of these space weathering processes on a deposit of volatiles in a lunar cold trap through simulations. We simulate the development of a column of material near the surface of the Moon resulting from space weathering. This simulation treats a column of material at a lunar cold trap and focuses on the hydrogen content of the column. We model space weathering processes on several time and spatial scales to simulate the constant rain of micrometeoroids as well as sporadic larger impactors occurring near the cold traps to determine the retention efficiency of the cold traps. We perform the Monte Carlo simulation over many columns of material to determine the expectation value for hydrogen content of the top few meters of soil for comparison with Lunar Prospector neutron data.

  10. Dynamics Of Ions In A Radio-Frequency Quadrupole Trap

    NASA Technical Reports Server (NTRS)

    Prestage, John D.; Williams, Angelyn P.; Maleki, Lutfollah

    1994-01-01

    Report describes computer-simulation study of motions of various numbers of ions in Paul trap. Study part of continuing effort to understand motions of trapped charged particles (atoms, ions, molecules, or dust particles). Motions characterized in terms of heating by radio-frequency fields, formation of crystallike structures in cold clouds of trapped particles, and other phenomena important in operation of radio-frequency traps in frequency standards.

  11. Space weathering on volatile deposits in lunar cold traps

    NASA Astrophysics Data System (ADS)

    Crider, D.; Vondrak, R.

    There are several mechanisms acting at the cold traps that can alter the inventory of volatiles there, including micrometeoroid bombardment, solar wind and magnetospheric ion sputtering, photon-stimulated desorption, and sublimation. We investigate the effects of these space weathering processes on a deposit of volatiles in a lunar cold trap by simulating the development of a column of material near the surface of the Moon. This simulation treats a column of material at a lunar cold trap and focuses on the hydrogen content of the column. We model space weathering processes on several time and spatial scales to simulate the constant rain of micrometeoroids as well as sporadic larger impactors occurring near the cold traps to determine the retention efficiency of the cold traps. We perform the Monte Carlo simulation over many columns of material to determine the expected hydrogen content of the top few meters of soil for comparison with Lunar Prospector neutron data. Each column is initialized with a random starting depth profile of hydrogen content assuming very immature soil. Time is allowed to run for 1 billion years and all changes to the column are calculated. An impactor flux from Gault [1972] is imposed to determine the timing and location of all nearby impacts. Nearby impacts excavate material from the column, exposing material from depth. More distant impacts cover the column with an ejecta blanket with a size and time dependent maturity value. In between impacts, the competing short term effects are simulated. Using the steady state delivery rate of water vapor to the lunar cold traps from Crider and Vondrak [2002], we find that the removal rate from space weathering processes does not exceed the rate at which volatiles are delivered to the cold traps on average. Together with the steady migration of hydrogen released from the soil elsewhere on the Moon, the predicted hydrogen content of the topmost meter of regolith in cold traps is within a factor of 2 of

  12. Quantum computing with trapped ions

    SciTech Connect

    Hughes, R.J.

    1998-01-01

    The significance of quantum computation for cryptography is discussed. Following a brief survey of the requirements for quantum computational hardware, an overview of the ion trap quantum computation project at Los Alamos is presented. The physical limitations to quantum computation with trapped ions are analyzed and an assessment of the computational potential of the technology is made.

  13. Halo ion trap mass spectrometer.

    PubMed

    Austin, Daniel E; Wang, Miao; Tolley, Samuel E; Maas, Jeffrey D; Hawkins, Aaron R; Rockwood, Alan L; Tolley, H Dennis; Lee, Edgar D; Lee, Milton L

    2007-04-01

    We describe a novel radio frequency ion trap mass analyzer based on toroidal trapping geometry and microfabrication technology. The device, called the halo ion trap, consists of two parallel ceramic plates, the facing surfaces of which are imprinted with sets of concentric ring electrodes. Radii of the imprinted rings range from 5 to 12 mm, and the spacing between the plates is 4 mm. Unlike conventional ion traps, in which hyperbolic metal electrodes establish equipotential boundary conditions, electric fields in the halo ion trap are established by applying different radio frequency potentials to each ring. The potential on each ring can be independently optimized to provide the best trapping field. The halo ion trap features an open structure, allowing easy access for in situ ionization. The toroidal geometry provides a large trapping and analyzing volume, increasing the number of ions that can be stored and reducing the effects of space-charge on mass analysis. Preliminary mass spectra show resolution (m/Deltam) of 60-75 when the trap is operated at 1.9 MHz and 500 Vp-p. PMID:17335180

  14. Mini ion trap mass spectrometer

    DOEpatents

    Dietrich, D.D.; Keville, R.F.

    1995-09-19

    An ion trap is described which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10{sup 9} and commercial mass spectrometers requiring 10{sup 4} ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products. 10 figs.

  15. Mini ion trap mass spectrometer

    DOEpatents

    Dietrich, Daniel D.; Keville, Robert F.

    1995-01-01

    An ion trap which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10.sup.9 and commercial mass spectrometers requiring 10.sup.4 ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products.

  16. Ion funnel ion trap and process

    DOEpatents

    Belov, Mikhail E [Richland, WA; Ibrahim, Yehia M [Richland, WA; Clowers, Biran H [West Richland, WA; Prior, David C [Hermiston, OR; Smith, Richard D [Richland, WA

    2011-02-15

    An ion funnel trap is described that includes a inlet portion, a trapping portion, and a outlet portion that couples, in normal operation, with an ion funnel. The ion trap operates efficiently at a pressure of .about.1 Torr and provides for: 1) removal of low mass-to-charge (m/z) ion species, 2) ion accumulation efficiency of up to 80%, 3) charge capacity of .about.10,000,000 elementary charges, 4) ion ejection time of 40 to 200 .mu.s, and 5) optimized variable ion accumulation times. Ion accumulation with low concentration peptide mixtures has shown an increase in analyte signal-to-noise ratios (SNR) of a factor of 30, and a greater than 10-fold improvement in SNR for multiply charged analytes.

  17. Lunar Cold Trap Contamination by Landing Vehicles

    NASA Technical Reports Server (NTRS)

    Shipley, Scott T.; Metzger, Philip T.; Lane, John E.

    2014-01-01

    Tools have been developed to model and simulate the effects of lunar landing vehicles on the lunar environment (Metzger, 2011), mostly addressing the effects of regolith erosion by rocket plumes and the fate of the ejected lunar soil particles (Metzger, 2010). These tools are being applied at KSC to predict ejecta from the upcoming Google Lunar X-Prize Landers and how they may damage the historic Apollo landing sites. The emerging interest in lunar mining poses a threat of contamination to pristine craters at the lunar poles, which act as "cold traps" for water and may harbor other valuable minerals Crider and Vondrak (2002). The KSC Granular Mechanics and Regolith Operations Lab tools have been expanded to address the probability for contamination of these pristine "cold trap" craters.

  18. Universal collisional activation ion trap mass spectrometry

    DOEpatents

    McLuckey, S.A.; Goeringer, D.E.; Glish, G.L.

    1993-04-27

    A universal collisional activation ion trap comprises an ion trapping means containing a bath gas and having connected thereto a noise signal generator. A method of operating a universal collisional activation ion trap comprises the steps of: providing an ion trapping means; introducing into the ion trapping means a bath gas; and, generating a noise signal within the ion trapping means; introducing into the ion trapping means a substance that, when acted upon by the noise signal, undergoes collisional activation to form product ions.

  19. Universal collisional activation ion trap mass spectrometry

    DOEpatents

    McLuckey, Scott A.; Goeringer, Douglas E.; Glish, Gary L.

    1993-01-01

    A universal collisional activation ion trap comprises an ion trapping means containing a bath gas and having connected thereto a noise signal generator. A method of operating a universal collisional activation ion trap comprises the steps of: providing an ion trapping means; introducing into the ion trapping means a bath gas; and, generating a noise signal within the ion trapping means; introducing into the ion trapping means a substance that, when acted upon by the noise signal, undergoes collisional activation to form product ions.

  20. Note: High density pulsed molecular beam for cold ion chemistry

    SciTech Connect

    Kokish, M. G.; Rajagopal, V.; Marler, J. P.; Odom, B. C.

    2014-08-15

    A recent expansion of cold and ultracold molecule applications has led to renewed focus on molecular species preparation under ultrahigh vacuum conditions. Meanwhile, molecular beams have been used to study gas phase chemical reactions for decades. In this paper, we describe an apparatus that uses pulsed molecular beam technology to achieve high local gas densities, leading to faster reaction rates with cold trapped ions. We characterize the beam's spatial profile using the trapped ions themselves. This apparatus could be used for preparation of molecular species by reactions requiring excitation of trapped ion precursors to states with short lifetimes or for obtaining a high reaction rate with minimal increase of background chamber pressure.

  1. Experimental investigation of planar ion traps

    SciTech Connect

    Pearson, C. E.; Leibrandt, D. R.; Bakr, W. S.; Mallard, W. J.; Brown, K. R.; Chuang, I. L.

    2006-03-15

    Chiaverini et al. [Quantum Inf. Comput. 5, 419 (2005)] recently suggested a linear Paul trap geometry for ion-trap quantum computation that places all of the electrodes in a plane. Such planar ion traps are compatible with modern semiconductor fabrication techniques and can be scaled to make compact, many-zone traps. In this paper we present an experimental realization of planar ion traps using electrodes on a printed circuit board to trap linear chains of tens of charged particles of 0.44 {mu}m diameter in a vacuum of 15 Pa (10{sup -1} torr). With these traps we address concerns about the low trap depth of planar ion traps and develop control electrode layouts for moving ions between trap zones without facing some of the technical difficulties involved in an atomic ion-trap experiment. Specifically, we use a trap with 36 zones (77 electrodes) arranged in a cross to demonstrate loading from a traditional four-rod linear Paul trap, linear ion movement, splitting and joining of ion chains, and movement of ions through intersections. We further propose an additional dc-biased electrode above the trap which increases the trap depth dramatically, and a planar ion-trap geometry that generates a two-dimensional lattice of point Paul traps.

  2. EDITORIAL: Modern applications of trapped ions Modern applications of trapped ions

    NASA Astrophysics Data System (ADS)

    Knoop, Martina; Hilico, Laurent; Eschner, Jürgen

    2009-08-01

    investigation of cold molecular ions and clusters are among the fastest growing topics, leading to ultracold chemistry at the single-particle scale. The next edition of this meeting series will take the name of European Conference on Trapped Ions (ECTI) and will be held in the UK in 2010. We are looking forward to this event, which will offer the possibility to continue the fruitful interaction between research groups that employ ion traps in widely different contexts, and to take the next snapshot of this dynamic research area.

  3. Microfabricated linear Paul-Straubel ion trap

    DOEpatents

    Mangan, Michael A.; Blain, Matthew G.; Tigges, Chris P.; Linker, Kevin L.

    2011-04-19

    An array of microfabricated linear Paul-Straubel ion traps can be used for mass spectrometric applications. Each ion trap comprises two parallel inner RF electrodes and two parallel outer DC control electrodes symmetric about a central trap axis and suspended over an opening in a substrate. Neighboring ion traps in the array can share a common outer DC control electrode. The ions confined transversely by an RF quadrupole electric field potential well on the ion trap axis. The array can trap a wide array of ions.

  4. A Cold Strontium Ion Source

    NASA Astrophysics Data System (ADS)

    Erickson, Christopher J.; Lyon, Mary; Blaser, Kelvin; Harper, Stuart; Durfee, Dallin

    2010-03-01

    We present a cold ion source for strontium 87. The source is based off of a standard Low-Velocity-Intense-Source (LVIS) for strontium using permanent magnets in place of anti-Helmholtz coils. Atoms from the LVIS are then ionized in a two photon process as they pass a 20kV anode plate. The result is a mono-energetic beam of ions whose velocity is tunable. Applications for the ions include spectroscopy and ion interferometry.

  5. Microscale ion trap mass spectrometer

    DOEpatents

    Ramsey, J. Michael; Witten, William B.; Kornienko, Oleg

    2002-01-01

    An ion trap for mass spectrometric chemical analysis of ions is delineated. The ion trap includes a central electrode having an aperture; a pair of insulators, each having an aperture; a pair of end cap electrodes, each having an aperture; a first electronic signal source coupled to the central electrode; a second electronic signal source coupled to the end cap electrodes. The central electrode, insulators, and end cap electrodes are united in a sandwich construction where their respective apertures are coaxially aligned and symmetric about an axis to form a partially enclosed cavity having an effective radius r.sub.0 and an effective length 2z.sub.0, wherein r.sub.0 and/or z.sub.0 are less than 1.0 mm, and a ratio z.sub.0 /r.sub.0 is greater than 0.83.

  6. Study of Cold Potassium Atom - Calcium Ion Reactions

    NASA Astrophysics Data System (ADS)

    Egodapitiya, Kisra; Gang, Shu; Clark, Robert; Brown, Kenneth

    2016-05-01

    We report on our progress towards constructing a hybrid system for studying reactions between cold Potassium (K) atoms and cold Calcium (Ca+) ions. Ca+ ions will be trapped and Doppler-cooled inside a linear quadrupole ion trap. Cold K atoms will be created inside a magneto optical trap, such that the ion and the atoms are in an overlapping volume. Trapping and re-pumping beams for the Potassium MOT are derived from the same laser with wavelength 766 nm using two acousto optic modulators. The reaction products will be detected using a time-of- flight mass spectrometer that is designed to detect radially ejected ions. The main objective of this experiment is to study the rate coefficients, and identification of reaction channels between cold K atoms and Ca+ ions. Subsequently this setup will be used to study reactions between cold K atoms and sympathetically cooled molecular ions such as CaO+, and to study internal state quenching of molecular ions.

  7. Cryogenic ion trapping systems with surface-electrode traps

    NASA Astrophysics Data System (ADS)

    Antohi, P. B.; Schuster, D.; Akselrod, G. M.; Labaziewicz, J.; Ge, Y.; Lin, Z.; Bakr, W. S.; Chuang, I. L.

    2009-01-01

    We present two simple cryogenic rf ion trap systems in which cryogenic temperatures and ultra high vacuum pressures can be reached in as little as 12 h. The ion traps are operated either in a liquid helium bath cryostat or in a low vibration closed cycle cryostat. The fast turn around time and availability of buffer gas cooling made the systems ideal for testing surface-electrode ion traps. The vibration amplitude of the closed cycled cryostat was found to be below 106 nm. We evaluated the systems by loading surface-electrode ion traps with S88r+ ions using laser ablation, which is compatible with the cryogenic environment. Using Doppler cooling we observed small ion crystals in which optically resolved ions have a trapped lifetime over 2500 min.

  8. Improved Linear-Ion-Trap Frequency Standard

    NASA Technical Reports Server (NTRS)

    Prestage, John D.

    1995-01-01

    Improved design concept for linear-ion-trap (LIT) frequency-standard apparatus proposed. Apparatus contains lengthened linear ion trap, and ions processed alternately in two regions: ions prepared in upper region of trap, then transported to lower region for exposure to microwave radiation, then returned to upper region for optical interrogation. Improved design intended to increase long-term frequency stability of apparatus while reducing size, mass, and cost.

  9. A single trapped ion in a finite range trap

    SciTech Connect

    Bagheri Harouni, M.; Davoudi Darareh, M.

    2011-04-15

    Research Highlights: > We present a method to describe dynamics of an ion confined in a finite size trap. > The trap is modeled with a potential in the context of an f-deformed oscillator. > The ion exhibits nonclassical properties such as squeezing and quantum interference. > . > Also this system can be used to generate highly excited motional Fock state. > The Hilbert space size effects and nano traps can be investigated by this model. - Abstract: This paper presents a method to describe dynamics of an ion confined in a realistic finite range trap. We model this realistic potential with a solvable one and we obtain dynamical variables (raising and lowering operators) of this potential. We consider coherent interaction of this confined ion in a finite range trap and we show that its center-of-mass motion steady state is a special kind of nonlinear coherent states. Physical properties of this state and their dependence on the finite range of potential are studied.

  10. Atomic Clock Based On Linear Ion Trap

    NASA Technical Reports Server (NTRS)

    Prestage, John D.; Dick, G. John

    1992-01-01

    Highly stable atomic clock based on excitation and measurement of hyperfine transition in 199Hg+ ions confined in linear quadrupole trap by radio-frequency and static electric fields. Configuration increases stability of clock by enabling use of enough ions to obtain adequate signal while reducing non-thermal component of motion of ions in trapping field, reducing second-order Doppler shift of hyperfine transition. Features described in NPO-17758 "Linear Ion Trap for Atomic Clock." Frequency standard based on hyperfine transition described in NPO-17456, "Trapped-Mercury-Ion Frequency Standard."

  11. Trapped-Mercury-Ion Frequency Standard

    NASA Technical Reports Server (NTRS)

    Prestage, John D.; Dick, G. John; Maleki, Lutfollah

    1991-01-01

    Report describes principle of operation, design, and results of initial measurements on trapped-mercury-ion frequency-standard apparatus at NASA's Jet Propulsion Laboratory. New frequency standard being developed. Based on linear ion trap described in (NPO-17758). Expected to show much better short-term frequency stability because of increased ion-storage capacity.

  12. New ion trap for frequency standard applications

    NASA Technical Reports Server (NTRS)

    Prestage, J. D.; Dick, G. J.; Maleki, L.

    1989-01-01

    A novel linear ion trap was designed, which permits storage of a large number of ions with reduced susceptibility to the second-order Doppler effect caused by the RF confining fields. This new trap should store about 20 times the number of ions as a conventional RF trap with no corresponding increase in second-order Doppler shift from the confining field. In addition, the sensitivity of this shift to trapping parameters, i.e., RF voltage, RF frequency, and trap size, is greatly reduced.

  13. Ultrafast entanglement of trapped ions

    NASA Astrophysics Data System (ADS)

    Neyenhuis, Brian; Johnson, Kale; Mizrahi, Jonathan; Wong-Campos, David; Monroe, Christopher

    2014-05-01

    We have demonstrated ultrafast spin-motion entanglement of a single atomic ion using a short train of intense laser pulses. This pulse train gives the ion a spin-dependent kick where each spin state receives a discrete momentum kick in opposite directions. Using a series of these spin-dependent kicks we can realize a two qubit gate. In contrast to gates using spectroscopically resolved motional sidebands, these gates may be performed faster than the trap oscillation period, making them potentially less sensitive to noise. Additionally this gate is temperature insensitive and does not require the ions to be cooled to the Lamb-Dicke limit. We show that multiple kicks can be strung together to create a ``Schrodinger cat'' like state, where the large separation between the two parts of the wavepacket allow us to accumulate the phase shift necessary for a gate in a shorter amount of time. We will present a realistic pulse scheme for a two ion gate, and our progress towards its realization. This work is supported by grants from the U.S. Army Research Office with funding from the DARPA OLE program, IARPA, and the MURI program; and the NSF Physics Frontier Center at JQI.

  14. Cryogenic resonator design for trapped ion experiments in Paul traps

    NASA Astrophysics Data System (ADS)

    Brandl, M. F.; Schindler, P.; Monz, T.; Blatt, R.

    2016-06-01

    Trapping ions in Paul traps require high radio frequency voltages, which are generated using resonators. When operating traps in a cryogenic environment, an in-vacuum resonator showing low loss is crucial to limit the thermal load to the cryostat. In this study, we present a guide for the design and production of compact, shielded cryogenic resonators. We produced and characterized three different types of resonators and furthermore demonstrate efficient impedance matching of these resonators at cryogenic temperatures.

  15. Three-Rod Linear Ion Traps

    NASA Technical Reports Server (NTRS)

    Janik, Gary R.; Prestage, John D.; Maleki, Lutfollah

    1993-01-01

    Three-parallel-rod electrode structures proposed for use in linear ion traps and possibly for electrostatic levitation of macroscopic particles. Provides wider viewing angle because they confine ions in regions outside rod-electrode structures.

  16. Trapped Ion Optical Clocks at NPL

    SciTech Connect

    Margolis, H. S.; Barwood, G. P.; Hosaka, K.; Klein, H. A.; Lea, S. N.; Walton, B. R.; Webster, S. A.; Gill, P.; Huang, G.; Stannard, A.

    2006-11-07

    Forbidden transitions in single laser-cooled trapped ions provide highly stable and accurate references for optical frequency standards. This paper describes recent progress on strontium and ytterbium ion optical frequency standards under development at NPL.

  17. Dynamical Decoupling Using Trapped Ions

    NASA Astrophysics Data System (ADS)

    Biercuk, Michael; Uys, Hermann; Vandevender, Aaron; Shiga, Nobuyasu; Itano, Wayne; Bollinger, John

    2009-05-01

    We present a detailed experimental study of the Uhrig Dynamical Decoupling (UDD) sequence in a variety of noise environments. Our qubit system consists of a crystalline array of ^9Be^+ ions confined in a Penning trap. We use an electron-spin-flip transition as our qubit manifold and drive qubit rotations using a quasi-optical 124 GHz microwave system. We study the effect of the UDD sequence in mitigating phase errors and compare against the well-known CPMG-style spin echo as a function of pulse number, rotation axis, noise spectrum, and noise strength. Our results show good agreement with theoretical predictions for qubit decoherence in the presence of classical phase noise, accounting for the effect of finite-duration π pulses. Finally, we demonstrate that the Uhrig sequence is more robust against systematic over/underrotation and detuning errors than is multipulse spin echo, despite the precise prescription for pulse-timing in UDD.

  18. Ion traps fabricated in a CMOS foundry

    SciTech Connect

    Mehta, K. K.; Ram, R. J.; Eltony, A. M.; Chuang, I. L.; Bruzewicz, C. D.; Sage, J. M. Chiaverini, J.

    2014-07-28

    We demonstrate trapping in a surface-electrode ion trap fabricated in a 90-nm CMOS (complementary metal-oxide-semiconductor) foundry process utilizing the top metal layer of the process for the trap electrodes. The process includes doped active regions and metal interconnect layers, allowing for co-fabrication of standard CMOS circuitry as well as devices for optical control and measurement. With one of the interconnect layers defining a ground plane between the trap electrode layer and the p-type doped silicon substrate, ion loading is robust and trapping is stable. We measure a motional heating rate comparable to those seen in surface-electrode traps of similar size. This demonstration of scalable quantum computing hardware utilizing a commercial CMOS process opens the door to integration and co-fabrication of electronics and photonics for large-scale quantum processing in trapped-ion arrays.

  19. Active stabilization of ion trap radiofrequency potentials

    NASA Astrophysics Data System (ADS)

    Johnson, K. G.; Wong-Campos, J. D.; Restelli, A.; Landsman, K. A.; Neyenhuis, B.; Mizrahi, J.; Monroe, C.

    2016-05-01

    We actively stabilize the harmonic oscillation frequency of a laser-cooled atomic ion confined in a radiofrequency (rf) Paul trap by sampling and rectifying the high voltage rf applied to the trap electrodes. We are able to stabilize the 1 MHz atomic oscillation frequency to be better than 10 Hz or 10 ppm. This represents a suppression of ambient noise on the rf circuit by 34 dB. This technique could impact the sensitivity of ion trap mass spectrometry and the fidelity of quantum operations in ion trap quantum information applications.

  20. Atomic ion clock with two ion traps, and method to transfer ions

    NASA Technical Reports Server (NTRS)

    Prestage, John D. (Inventor); Chung, Sang K. (Inventor)

    2011-01-01

    An atomic ion clock with a first ion trap and a second ion trap, where the second ion trap is of higher order than the first ion trap. In one embodiment, ions may be shuttled back and forth from one ion trap to the other by application of voltage ramps to the electrodes in the ion traps, where microwave interrogation takes place when the ions are in the second ion trap, and fluorescence is induced and measured when the ions are in the first ion trap. In one embodiment, the RF voltages applied to the second ion trap to contain the ions are at a higher frequency than that applied to the first ion trap. Other embodiments are described and claimed.

  1. Cryptography, quantum computation and trapped ions

    SciTech Connect

    Hughes, Richard J.

    1998-03-01

    The significance of quantum computation for cryptography is discussed. Following a brief survey of the requirements for quantum computational hardware, an overview of the ion trap quantum computation project at Los Alamos is presented. The physical limitations to quantum computation with trapped ions are analyzed and an assessment of the computational potential of the technology is made.

  2. Micro-fabricated stylus ion trap.

    PubMed

    Arrington, Christian L; McKay, Kyle S; Baca, Ehren D; Coleman, Jonathan J; Colombe, Yves; Finnegan, Patrick; Hite, Dustin A; Hollowell, Andrew E; Jördens, Robert; Jost, John D; Leibfried, Dietrich; Rowen, Adam M; Warring, Ulrich; Weides, Martin; Wilson, Andrew C; Wineland, David J; Pappas, David P

    2013-08-01

    An electroformed, three-dimensional stylus Paul trap was designed to confine a single atomic ion for use as a sensor to probe the electric-field noise of proximate surfaces. The trap was microfabricated with the UV-LIGA technique to reduce the distance of the ion from the surface of interest. We detail the fabrication process used to produce a 150 μm tall stylus trap with feature sizes of 40 μm. We confined single, laser-cooled, (25)Mg(+) ions with lifetimes greater than 2 h above the stylus trap in an ultra-high-vacuum environment. After cooling a motional mode of the ion at 4 MHz close to its ground state ( = 0.34 ± 0.07), the heating rate of the trap was measured with Raman sideband spectroscopy to be 387 ± 15 quanta/s at an ion height of 62 μm above the stylus electrodes. PMID:24007096

  3. Cooling of highly charged ions in a Penning trap

    SciTech Connect

    Gruber, L

    2000-03-31

    Highly charged ions are extracted from an electron beam ion trap and guided to Retrap, a cryogenic Penning trap, where they are merged with laser cooled Be{sup +} ions. The Be{sup +} ions act as a coolant for the hot highly charged ions and their temperature is dropped by about 8 orders of magnitude in a few seconds. Such cold highly charged ions form a strongly coupled nonneutral plasma exhibiting, under such conditions, the aggregation of clusters and crystals. Given the right mixture, these plasmas can be studied as analogues of high density plasmas like white dwarf interiors, and potentially can lead to the development of cold highly charged ion beams for applications in nanotechnology. Due to the virtually non existent Doppler broadening, spectroscopy on highly charged ions can be performed to an unprecedented precision. The density and the temperature of the Be{sup +} plasma were measured and highly charged ions were sympathetically cooled to similar temperatures. Molecular dynamics simulations confirmed the shape, temperature and density of the highly charged ions. Ordered structures were observed in the simulations.

  4. Spectroscopy with trapped highly charged ions

    SciTech Connect

    Beiersdorfer, P

    2008-01-23

    We give an overview of atomic spectroscopy performed on electron beam ion traps at various locations throughout the world. Spectroscopy at these facilities contributes to various areas of science and engineering, including but not limited to basic atomic physics, astrophysics, extreme ultraviolet lithography, and the development of density and temperature diagnostics of fusion plasmas. These contributions are accomplished by generating, for example, spectral surveys, making precise radiative lifetime measurements, accounting for radiative power emitted in a given wavelength band, illucidating isotopic effects, and testing collisional-radiative models. While spectroscopy with electron beam ion traps had originally focused on the x-ray emission from highly charged ions interacting with the electron beam, the operating modes of such devices have expanded to study radiation in almost all wavelength bands from the visible to the hard x-ray region; and at several facilities the ions can be studied even in the absence of an electron beam. Photon emission after charge exchange or laser excitation has been observed, and the work is no longer restricted to highly charged ions. Much of the experimental capabilities are unique to electron beam ion traps, and the work performed with these devices cannot be undertaken elsewhere. However, in other areas the work on electron beam ion traps rivals the spectroscopy performed with conventional ion traps or heavy-ion storage rings. The examples we present highlight many of the capabilities of the existing electron beam ion traps and their contributions to physics.

  5. Cold Atom Source Containing Multiple Magneto-Optical Traps

    NASA Technical Reports Server (NTRS)

    Ramirez-Serrano, Jaime; Kohel, James; Kellogg, James; Lim, Lawrence; Yu, Nan; Maleki, Lute

    2007-01-01

    An apparatus that serves as a source of a cold beam of atoms contains multiple two-dimensional (2D) magneto-optical traps (MOTs). (Cold beams of atoms are used in atomic clocks and in diverse scientific experiments and applications.) The multiple-2D-MOT design of this cold atom source stands in contrast to single-2D-MOT designs of prior cold atom sources of the same type. The advantages afforded by the present design are that this apparatus is smaller than prior designs.

  6. Improved trapping and transport of cold atoms for magnetic microscopy

    NASA Astrophysics Data System (ADS)

    Gadge, Amruta; James, T.; Li, X.; Lu, Bo; Garridogonzalez, N.; Finke, A.; Mellor, C.; Fromhold, M.; Koller, C.; Orucevic, F.; Kruger, Peter

    2016-05-01

    Using cold atoms, a very sensitive and high resolution magnetic and electric field sensor can be realised. Ultra-close trapping of atoms would improve the resolution of cold-atom based surface probes. The limitation on the trapping distance arises from strongly distance-dependent effects such as Casimir force, Johnson noise etc. We are constructing an experimental system to trap atoms at surface separations of less than a micron. We will demonstrate the possibility of using special surfaces such as silicon nitride membranes and graphene for sub-micron trapping. We have designed a 10-layer printed circuit board, which can magnetically trap the cold atom cloud and transport it precisely to a desired location. This gives us the ability to study multiple samples within the same vacuum environment. In order to achieve higher atom number in the initial trapping stages, we use a dual-color MOT technique for Rb-87 atoms. Using this technique we achieve a significant increase in atom number and decrease in temperature. In this talk, I will present the results of the dual color MOT. I will also report on results related to magnetic transport and sub-micron trapping of atoms.

  7. Nonlinear spectroscopy of trapped ions

    NASA Astrophysics Data System (ADS)

    Schlawin, Frank; Gessner, Manuel; Mukamel, Shaul; Buchleitner, Andreas

    2014-08-01

    Nonlinear spectroscopy employs a series of laser pulses to interrogate dynamics in large interacting many-body systems, and it has become a highly successful method for experiments in chemical physics. Current quantum optical experiments approach system sizes and levels of complexity that require the development of efficient techniques to assess spectral and dynamical features with scalable experimental overhead. However, established methods from optical spectroscopy of macroscopic ensembles cannot be applied straightforwardly to few-atom systems. Based on the ideas proposed in M. Gessner et al., (arXiv:1312.3365), we develop a diagrammatic approach to construct nonlinear measurement protocols for controlled quantum systems, and we discuss experimental implementations with trapped ion technology in detail. These methods, in combination with distinct features of ultracold-matter systems, allow us to monitor and analyze excitation dynamics in both the electronic and vibrational degrees of freedom. They are independent of system size, and they can therefore reliably probe systems in which, e.g., quantum state tomography becomes prohibitively expensive. We propose signals that can probe steady-state currents, detect the influence of anharmonicities on phonon transport, and identify signatures of chaotic dynamics near a quantum phase transition in an Ising-type spin chain.

  8. Simple analytic potentials for linear ion traps

    NASA Technical Reports Server (NTRS)

    Janik, G. R.; Prestage, J. D.; Maleki, L.

    1989-01-01

    A simple analytical model was developed for the electric and ponderomotive (trapping) potentials in linear ion traps. This model was used to calculate the required voltage drive to a mercury trap, and the result compares well with experiments. The model gives a detailed picture of the geometric shape of the trapping potenital and allows an accurate calculation of the well depth. The simplicity of the model allowed an investigation of related, more exotic trap designs which may have advantages in light-collection efficiency.

  9. Simple analytic potentials for linear ion traps

    NASA Technical Reports Server (NTRS)

    Janik, G. R.; Prestage, J. D.; Maleki, L.

    1990-01-01

    A simple analytical model was developed for the electric and ponderomotive (trapping) potentials in linear ion traps. This model was used to calculate the required voltage drive to a mercury trap, and the result compares well with experiments. The model gives a detailed picture of the geometric shape of the trapping potential and allows an accurate calculation of the well depth. The simplicity of the model allowed an investigation of related, more exotic trap designs which may have advantages in light-collection efficiency.

  10. Interchange mode excited by trapped energetic ions

    SciTech Connect

    Nishimura, Seiya

    2015-07-15

    The kinetic energy principle describing the interaction between ideal magnetohydrodynamic (MHD) modes with trapped energetic ions is revised. A model is proposed on the basis of the reduced ideal MHD equations for background plasmas and the bounce-averaged drift-kinetic equation for trapped energetic ions. The model is applicable to large-aspect-ratio toroidal devices. Specifically, the effect of trapped energetic ions on the interchange mode in helical systems is analyzed. Results show that the interchange mode is excited by trapped energetic ions, even if the equilibrium states are stable to the ideal interchange mode. The energetic-ion-induced branch of the interchange mode might be associated with the fishbone mode in helical systems.

  11. Ion-Atom Cold Collisions and Atomic Clocks

    NASA Technical Reports Server (NTRS)

    Prestage, John D.; Maleki, Lute; Tjoelker, Robert L.

    1997-01-01

    Collisions between ultracold neutral atoms have for some time been the subject of investigation, initially with hydrogen and more recently with laser cooled alkali atoms. Advances in laser cooling and trapping of neutral atoms in a Magneto-Optic Trap (MOT) have made cold atoms available as the starting point for many laser cooled atomic physics investigations. The most spectacularly successful of these, the observation of Bose-Einstein Condensation (BEC) in a dilute ultra-cold spin polarized atomic vapor, has accelerated the study of cold collisions. Experimental and theoretical studies of BEC and the long range interaction between cold alkali atoms is at the boundary of atomic and low temperature physics. Such studies have been difficult and would not have been possible without the development and advancement of laser cooling and trapping of neutral atoms. By contrast, ion-atom interactions at low temperature, also very difficult to study prior to modern day laser cooling, have remained largely unexplored. But now, many laboratories worldwide have almost routine access to cold neutral atoms. The combined technologies of ion trapping, together with laser cooling of neutrals has made these studies experimentally feasible and several very important, novel applications might come out of such investigations . This paper is an investigation of ion-atom interactions in the cold and ultra-cold temperature regime. Some of the collisional ion-atom interactions present at room temperature are very much reduced in the low temperature regime. Reaction rates for charge transfer between unlike atoms, A + B(+) approaches A(+) + B, are expected to fall rapidly with temperature, approximately as T(sup 5/2). Thus, cold mixtures of atoms and ions are expected to coexist for very long times, unlike room temperature mixtures of the same ion-atom combination. Thus, it seems feasible to cool ions via collisions with laser cooled atoms. Many of the conventional collisional interactions

  12. Experiments in Planar Multipole Ion Traps

    NASA Astrophysics Data System (ADS)

    Clark, Rob; Burke, Timothy; Green, Dylan

    2016-05-01

    We present the design and demonstration of multipole ion traps based on concentric rings. We have developed both surface-electrode and layered planar trap designs which enable one to null the quadratic term in the electric potential to a high degree. Experiments demonstrating frequency upconversion of an applied signal demonstrate the nonlinear dynamics present in the trap. Applications include quantum chaos, ultracold chemistry, and, potentially, mass spectrometry. We acknowledge support from the Research Corporation for Science Advancement and from The Citadel Foundation.

  13. Optical probing of cold trapped atoms

    NASA Technical Reports Server (NTRS)

    Fox, R. W.; Gilbert, S. L.; Hollberg, L.; Marquardt, J. H.; Robinson, H. G.

    1993-01-01

    Transitions between excited states of laser-cooled and laser-trapped rubidium and cesium atoms are probed by use of fiber and diode lasers. High-resolution Doppler-free spectra are detected by observation of the absorption and fluorescence of light from the intermediate level of two-step cascade systems. The optical double-resonance spectra show Autler-Townes splitting in the weak probe limit and more complicated spectra for a strongly coupled three-level system.

  14. A hybrid quantum system of ultracold atoms and trapped ions

    NASA Astrophysics Data System (ADS)

    Sias, Carlo; Ratschbacher, Lothar; Zipkes, Christoph; Koehl, Michael; AMOP Team

    2011-05-01

    In the last decades, trapped ions and ultracold atoms have emerged as exceptionally controllable experimental systems to investigate fundamental physics, ranging from quantum information science to simulations of condensed matter models. Even though they share some common grounds in experimental techniques, such as laser cooling, ion trapping and atom trapping have developed very much independently, and only little cross-pollination has been seen. In our experiment we study how cold atoms can be combined with single trapped ions to create a new hybrid quantum system with tailored properties. We have deterministically placed a single ion into an atomic Bose Einstein condensate and demonstrated independent control over the two components within the hybrid system. We have studied the fundamental interaction processes and observed sympathetic cooling of the single ion by the condensate. Additionally, we have characterized elastic and inelastic atom- ion collisions and measured the energy-dependent reaction rate constants. Our experiment paves the way for coupling atomic quantum many-body states to an independently controllable single-particle, giving access to a wealth of novel physics and to completely new detection and manipulation techniques.

  15. Trapping cold atoms using surface-grown carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Petrov, P. G.; Machluf, S.; Younis, S.; Macaluso, R.; David, T.; Hadad, B.; Japha, Y.; Keil, M.; Joselevich, E.; Folman, R.

    2009-04-01

    We present a feasibility study for loading cold atomic clouds into magnetic traps created by single-wall carbon nanotubes grown directly onto dielectric surfaces. We show that atoms may be captured for experimentally sustainable nanotube currents, generating trapped clouds whose densities and lifetimes are sufficient to enable detection by simple imaging methods. This opens the way for a different type of conductor to be used in atomchips, enabling atom trapping at submicron distances, with implications for both fundamental studies and for technological applications.

  16. Cavity QED in a molecular ion trap

    SciTech Connect

    Schuster, D. I.; Bishop, Lev S.; Chuang, I. L.; DeMille, D.; Schoelkopf, R. J.

    2011-01-15

    We propose a class of experiments using rotational states of dipolar molecular ions trapped near an on-chip superconducting microwave cavity. Molecular ions have several advantages over neutral molecules for such cavity quantum electrodynamics experiments. In particular, ions can be loaded easily into deep rf traps and are held independent of their internal state. An analysis of the detection efficiency for, and coherence properties of, the molecular ions is presented. We discuss approaches for manipulating quantum information and performing high-resolution rotational spectroscopy using this system.

  17. Trapping cold molecules and atoms: Simultaneous magnetic deceleration and trapping of cold molecular Oxygen with Lithium atoms

    NASA Astrophysics Data System (ADS)

    Akerman, Nitzan; Karpov, Michael; Segev, Yair; Bibelink, Natan; Narevicius, Julia; Narevicius, Edvardas

    2016-05-01

    Cooling molecules to the ultra-cold regime remains a major challenge in the growing field of cold molecules. The molecular internal degrees of freedom complicate the effort of direct application of laser cooling. An alternative and general path towards ultra-cold molecules relies on sympathetic cooling via collisions with laser-cooled atoms. Here, we demonstrate the first step towards application of sympathetic cooling by co-trapping of molecular Oxygen with Lithium atoms in a magnetic trap at a temperature of 300 mK. Our experiment begins with a pulsed supersonic beam which is a general source for cold high-flux atomic and molecular beams. Although the supersonic expansion efficiently cools the beam to temperatures below 1K, it also accelerates the beam to high mean velocities. We decelerate a beam of O2 in a moving magnetic trap decelerator from 375 m/s to a stop. We entrained the molecular beam with Li atoms by laser ablation prior to deceleration. The deceleration ends with loading the molecules and atoms into a static quadrupole trap, which is generated by two permanent magnets. We estimate 109 trapped molecules with background limited lifetime of 0.6 Sec. Our achievement enables application of laser cooling on the Li atoms in order to sympathetically cool the O2.

  18. A toroidal trap for cold {}^{87}{Rb} atoms using an rf-dressed quadrupole trap

    NASA Astrophysics Data System (ADS)

    Chakraborty, A.; Mishra, S. R.; Ram, S. P.; Tiwari, S. K.; Rawat, H. S.

    2016-04-01

    We demonstrate the trapping of cold {}87{Rb} atoms in a toroidal geometry using a radio frequency (rf) dressed quadrupole magnetic trap formed by superposing a strong rf-field on a quadrupole trap. This rf-dressed quadrupole trap has the minimum potential away from the quadrupole trap centre on a circular path which facilitates trapping in toroidal geometry. In these experiments, the laser cooled atoms were first trapped in a quadrupole trap, then cooled evaporatively using a weak rf-field, and finally trapped in an rf-dressed quadrupole trap. The radius of the toroid could be varied by varying the frequency of the dressing rf-field. It has also been demonstrated that a single rf source and an antenna can be used for the rf-evaporative cooling as well as for the rf-dressing of atoms. The atoms trapped in the toroidal trap may have applications in the realization of an atom gyroscope as well as in studying the quantum gases in low dimensions.

  19. Synthesis of Cold Antihydrogen in a Cusp Trap

    SciTech Connect

    Enomoto, Y.; Nagata, Y.; Kanai, Y.; Mohri, A.; Kuroda, N.; Kim, C. H.; Torii, H. A.; Fujii, K.; Ohtsuka, M.; Tanaka, K.; Matsuda, Y.; Michishio, K.; Nagashima, Y.; Higaki, H.; Corradini, M.; Leali, M.; Lodi-Rizzini, E.; Mascagna, V.; Venturelli, L.; Zurlo, N.

    2010-12-10

    We report here the first successful synthesis of cold antihydrogen atoms employing a cusp trap, which consists of a superconducting anti-Helmholtz coil and a stack of multiple ring electrodes. This success opens a new path to make a stringent test of the CPT symmetry via high precision microwave spectroscopy of ground-state hyperfine transitions of antihydrogen atoms.

  20. Structure of the alkali-metal-atom + strontium molecular ions: Towards photoassociation and formation of cold molecular ions

    SciTech Connect

    Aymar, M.; Dulieu, O.; Guerout, R.

    2011-08-14

    The potential energy curves, permanent and transition dipole moments, and the static dipolar polarizability, of molecular ions composed of one alkali-metal atom and a strontium ion are determined with a quantum chemistry approach. The molecular ions are treated as effective two-electron systems and are treated using effective core potentials including core polarization, large gaussian basis sets, and full configuration interaction. In the perspective of upcoming experiments aiming at merging cold atom and cold ion traps, possible paths for radiative charge exchange, photoassociation of a cold lithium or rubidium atom and a strontium ion are discussed, as well as the formation of stable molecular ions.

  1. Small Scale Cold Traps on Airless Planetary Bodies

    NASA Astrophysics Data System (ADS)

    Hayne, Paul O.; Aharonson, O.; Williams, J.; Siegler, M. A.; Greenhagen, B. T.; Bandfield, J.; Vasavada, A. R.; Paige, D. A.; Diviner Lunar Radiometer Science Team

    2013-10-01

    Lacking an atmosphere to transport heat, temperatures on airless bodies are primarily controlled by latitude and local time. However, local topography strongly affects temperatures at the surface and in the subsurface by changing the intensity and timing of insolation. In the case of low-obliquity bodies such as Mercury and the Earth’s moon, topography near the poles casts perennial shadows where volatiles such as water ice may be cold-trapped for billions of years. Prior studies have focused primarily on large contiguous cold traps > 1 km resolvable by instruments in lunar orbit. In this investigation, we used infrared measurements of the Moon, thermal models, and a statistical rough surface model to show that such cold traps may exist on a vast range of scales, from the largest impact craters, down to the skin depth of the diurnal temperature oscillation. The extremely insulating nature of planetary regolith leads to extreme temperature gradients and shallow diurnal skin depths. For example, the lunar 29-day diurnal temperature oscillation is damped to ~1% at a depth of 0.5 m. Therefore, at latitudes > 60° where perennial shadow exists, cold traps as small as a few tens of centimeters could exist. As two test cases, we calculated the fractional surface areas on the Moon (obliquity = 1.6°) and Ceres (3-5°) where temperatures remain < 110 K all year round, such that water ice is thermally stable at the surface for billions of years. We also calculated fractional areas where subsurface temperatures are < 145 K, such that subsurface ice deposits are stable on similar timescales. Finally, we will discuss the implications of these proposed small-scale cold traps for other airless bodies, including asteroids and giant planet satellites.

  2. Trapping and evolution dynamics of strongly magnetized cold gases

    NASA Astrophysics Data System (ADS)

    Choi, Jae-Hoon

    Cold Rydberg atoms and ultracold plasmas have been studied in the strong-magnetization regime. In this new territory, novel atomic and plasma states---such as guiding-center drift Rydberg attains and strongly magnetized, quasi-neutral, ultracold plasmas---have been created and investigated. The evolution dynamics studies of these exotic diamagnetic forms of matter, made possible by implementing a superconducting magnetic atom trap, revealed rich dynamical features in the systems: The Landau-quantized energy structure has led to entirely different evolutions of the highly excited atoms in laser-excited or drift Rydberg states than in magnetic-field-free cases; and the presence of the strong magnetic field has drastically altered the collisional behavior and expansion dynamics of the plasmas. Furthermore, atom cooling and trapping methodology has been extended in multiple directions. Firstly, laser cooling and magnetic trapping of ground-state atoms has been demonstrated in magnetic; fields exceeding 3 Tesla, representing a 20-fold increase in the field-strength of cold-atom traps. Secondly, the trapping of Rydberg atoms with a lifetime of 80 ms has been achieved. This trapping technique exploits the quasi-free nature of Rydberg electrons, which can be adopted in other forms of Rydberg-atom trapping. Lastly; the trapping of two-component, ultracold plasmas has been demonstrated in a nested Penning-trap configuration. The confinement of quasi-neutral ultracold plasmas allowed us to observe novel effects such as the correlation between the ionic oscillation and the electron energy distribution.

  3. A trapped mercury 199 ion frequency standard

    NASA Technical Reports Server (NTRS)

    Cutler, L. S.; Giffard, R. P.; Mcguire, M. D.

    1982-01-01

    Mercury 199 ions confined in an RF quadrupole trap and optically pumped by mercury 202 ion resonance light are investigated as the basis for a high performance frequency standard with commercial possibilities. Results achieved and estimates of the potential performance of such a standard are given.

  4. Entanglement of trapped-ion clock states

    SciTech Connect

    Haljan, P. C.; Lee, P. J.; Brickman, K-A.; Acton, M.; Deslauriers, L.; Monroe, C.

    2005-12-15

    A Moelmer-Soerensen entangling gate is realized for pairs of trapped {sup 111}Cd{sup +} ions using magnetic-field insensitive 'clock' states and an implementation offering reduced sensitivity to optical phase drifts. The gate is used to generate the complete set of four entangled states, which are reconstructed and evaluated with quantum-state tomography. An average target-state fidelity of 0.79 is achieved, limited by available laser power and technical noise. The tomographic reconstruction of entangled states demonstrates universal quantum control of two ion qubits, which through multiplexing can provide a route to scalable architectures for trapped-ion quantum computing.

  5. An electrostatic autoresonant ion trap mass spectrometer

    SciTech Connect

    Ermakov, A. V.; Hinch, B. J.

    2010-01-15

    A new method for ion extraction from an anharmonic electrostatic trap is introduced. Anharmonicity is a common feature of electrostatic traps which can be used for small scale spatial confinement of ions, and this feature is also necessary for autoresonant ion extraction. With the aid of ion trajectory simulations, novel autoresonant trap mass spectrometers (ART-MSs) have been designed based on these very simple principles. A mass resolution {approx}60 is demonstrated for the prototypes discussed here. We report also on the pressure dependencies, and the (mV) rf field strength dependencies of the ART-MS sensitivity. Importantly the new MS designs do not require heavy magnets, tight manufacturing tolerances, introduction of buffer gases, high power rf sources, nor complicated electronics. The designs described here are very inexpensive to implement relative to other instruments, and can be easily miniaturized. Possible applications are discussed.

  6. Fundamental studies of ion injection and trapping of electrosprayed ions on a quadrupole ion trap mass spectrometer

    NASA Astrophysics Data System (ADS)

    Quarmby, Scott Thomas

    The quadrupole ion trap is a highly versatile and sensitive analytical mass spectrometer. Because of the advantages offered by the ion trap, there has been intense interest in coupling it to ionization techniques such as electrospray which form ions externally to the ion trap. In this work, experiments and computer simulations were employed to study the injection of electrosprayed ions into the ion trap of a Finnigan MAT LCQ LC/MS n mass spectrometer. The kinetic energy distribution of the ion beam was characterized and found to be relatively wide, a result of the high pressures from the atmospheric pressure source. One of the most important experimental parameters which affects ion injection efficiency is the RF voltage applied to the ring electrode. A theoretical model was fit to experimental data allowing the optimum RF voltage for trapping a given m/z ion to be predicted. Computer simulations of ion motion were performed to study the effect of various instrumental parameters on trapping efficiency. A commercially available ion optics program, SIMION v6.0, was chosen because it allowed the actual ion trap electrode geometry including endcap holes to be simulated. In contrast to previous computer simulations, SIMION provided the ability to start ions outside the ion trap and to simulate more accurately the injection of externally formed ions. The endcap holes were found to allow the RF field to penetrate out of the ion trap and affect ions as they approached the ion trap. From these simulations, a model for the process by which injected ions are trapped was developed. Using these computer simulations, techniques of improving trapping efficiency were investigated. Most previous techniques perturb ions which are already in the ion trap and therefore cannot be used to accumulate ions; the ability to accumulate ions is a necessity with ionization sources such as electrospray which form ions continuously. One such novel technique for improving trapping efficiency

  7. Extended linear ion trap frequency standard apparatus

    NASA Technical Reports Server (NTRS)

    Prestage, John D. (Inventor)

    1995-01-01

    A linear ion trap for frequency standard applications is provided with a plurality of trapping rods equally spaced and applied quadruple rf voltages for radial confinement of atomic ions and biased level pins at each end for axial confinement of the ions. The trapping rods are divided into two linear ion trap regions by a gap in each rod in a common radial plane to provide dc discontinuity, thus dc isolating one region from the other. A first region for ion-loading and preparation fluorescence is biased with a dc voltage to transport ions into a second region for resonance frequency comparison with a local oscillator derived frequency while the second region is held at zero voltage. The dc bias voltage of the regions is reversed for transporting the ions back into the first region for fluorescence measurement. The dual mode cycle is repeated continuously for comparison and feedback control of the local oscillator derived frequency. Only the second region requires magnetic shielding for the resonance function which is sensitive to any ambient magnetic fields.

  8. Trapped-Ion Optical Frequency Standards

    NASA Astrophysics Data System (ADS)

    Schmidt, Piet O.; Leroux, Ian D.

    Optical frequency standards based on trapped atoms are the most accurate measurement devices we have available. They not only serve as superior time keepers but also lend themselves to a wide variety of applications ranging from tests of fundamental physics to the measurement of heights in relativistic geodesy. This chapter provides an introduction to the basics of optical frequency standards and clocks based on trapped ions and their applications.

  9. Interaction of field-aligned cold plasma flows with an equatorially-trapped hot plasma - Electrostatic shock formation

    NASA Technical Reports Server (NTRS)

    Singh, Nagendra

    1993-01-01

    Effects of equatorially trapped hot plasma on the highly supersonic cold-plasma flow occurring during early stage plasmaspheric refilling are studied by means of numerical simulations. It is shown that the equatorially trapped hot ions set up a potential barrier for the cold ion beams and facilitate formation of electrostatic shocks by reflecting them from the equatorial region. Simulations with and without the hot plasma show different flow properties; the formation of electrostatic shocks occur only in the former case. The simulation with the hot plasma also reveals that the magnetic trapping in conjunction with the evolution of the electrostatic potential barrier produces ion velocity distribution functions consisting of a cold core and a hot ring in the perpendicular velocity. Such a distribution function provides a source of free energy for equatorial waves. The corresponding electron population is warm and field-aligned.

  10. Sensitive detection of radiation trapping in cold-atom clouds

    SciTech Connect

    Beeler, Matthew; Stites, Ronald; Kim, Soo; Feeney, Laura; Bali, Samir

    2003-07-01

    In this paper, we calculate the effect of radiation trapping on the photon statistics of the light scattered from optical molasses. We propose that an intensity correlation function measurement may be sensitive to the presence of radiation trapping at an on-resonance optical depth as low as 0.1, more than an order of magnitude less than where effects of multiple scattering in cold-atom clouds have been previously observed [T. Walker, D. Sesko, and C. Wieman, Phys. Rev. Lett. 64, 408 (1990); D. Sesko, T. Walker, and C. Wieman, J. Opt. Soc. Am. B. 8, 946 (1991)].

  11. Motional-mode analysis of trapped ions

    NASA Astrophysics Data System (ADS)

    Kalis, Henning; Hakelberg, Frederick; Wittemer, Matthias; Mielenz, Manuel; Warring, Ulrich; Schaetz, Tobias

    2016-08-01

    We present two methods for characterization of motional-mode configurations that are generally applicable to the weak- and strong-binding limit of single or multiple trapped atomic ions. Our methods are essential to realize control of the individual as well as the common motional degrees of freedom. In particular, when implementing scalable radio-frequency trap architectures with decreasing ion-electrode distances, local curvatures of electric potentials need to be measured and adjusted precisely, e.g., to tune phonon tunneling and control effective spin-spin interaction. We demonstrate both methods using single 25Mg+ ions that are individually confined 40 μ m above a surface-electrode trap array and prepared close to the ground state of motion in three dimensions.

  12. Ion trapping study in eRHIC

    SciTech Connect

    Hao, Y.

    2011-03-28

    The ion trapping effect is an important beam dynamics issue in energy recovery linac (ERL). The ionized residue gas molecules can accumulate at the vicinity of the electron beam path and deteriorate the quality of the electron beam. In this paper, we present calculation results to address this issue in eRHIC and find best beam pattern to eliminate this effect. eRHIC is the future electron ion collider(EIC), which collides 5GeV to 30GeV electron beam from a new electron accelerator with the ion beam from existing RHIC ring. The electron accelerator adopts a multi-pass ERL, which contains 6 passes with 2 linacs per pass. The electron impacted ionization effect needs attention to ensure the quality of the electron beam. The high energy electrons ionize the residue gas in beam pipe. These ions may accumulate and are 'trapped' near the axis of the pipe where the electron beam passes, due to the interaction with the electron beam. The concentration of the ion may produce noticeable space charge field that affects the electron beam and neutralize the electron beam in the linacs. In the paper, we start with cross section of the ionization process and calculate the accumulation time, which are followed by the modeling to determine the criteria of the ion trapping. The ion trapping effect is determined by the longitudinal configuration of the electron bunches. The effect can be reduced or mitigate by some proper electron beam patterns. We will present these patterns with a linearized model. We present the linearized calculation on the ion motion in the cavity of multi-pass ERL and determine the stability of the ion motion from the results. We conclude that the ionized molecules won't accumulated in eRHIC linacs except both 40m ends. Electro-static clearing electrodes should be installed in those regions to remove the ions from accumulation.

  13. Hows and whys of ion trapping

    SciTech Connect

    Allison, J.; Stepnowski, R.M.

    1987-09-15

    Why trap ions. The localization of a single atomic particle in a vacuum is one of the most fundamental problems of physics and one of enduring interest. Working in the gas phase at low pressures, the chemist has the opportunity to study a variety of phenomena, if such species of interest can be contained for a period of time. Ion traps provide a unique chemical system available for a variety of experiments. The authors describe the bases of the technology, its strengths and limitations, and examples of its use.

  14. Electron beam ion source and electron beam ion trap (invited)

    SciTech Connect

    Becker, Reinard; Kester, Oliver

    2010-02-15

    The electron beam ion source (EBIS) and its trap variant [electron beam ion trap (EBIT)] celebrated their 40th and 20th anniversary, respectively, at the EBIS/T Symposium 2007 in Heidelberg. These technologically challenging sources of highly charged ions have seen a broad development in many countries over the last decades. In contrast to most other ion sources the recipe of improvement was not ''sorcery'' but a clear understanding of the physical laws and obeying the technological constraints. This review will report important achievements of the past as well as promising developments in the future.

  15. Trapped Atomic Ions and Quantum Information Processing

    SciTech Connect

    Wineland, D. J.; Leibfried, D.; Bergquist, J. C.; Blakestad, R. B.; Bollinger, J. J.; Britton, J.; Chiaverini, J.; Epstein, R. J.; Hume, D. B.; Itano, W. M.; Jost, J. D.; Koelemeij, J. C. J.; Langer, C.; Ozeri, R.; Reichle, R.; Rosenband, T.; Schaetz, T.; Schmidt, P. O.; Seidelin, S.; Shiga, N.

    2006-11-07

    The basic requirements for quantum computing and quantum simulation (single- and multi-qubit gates, long memory times, etc.) have been demonstrated in separate experiments on trapped ions. Construction of a large-scale information processor will require synthesis of these elements and implementation of high-fidelity operations on a very large number of qubits. This is still well in the future. NIST and other groups are addressing part of the scaling issue by trying to fabricate multi-zone arrays of traps that would allow highly-parallel and scalable processing. In the near term, some simple quantum processing protocols are being used to aid in quantum metrology, such as in atomic clocks. As the number of qubits increases, Schroedinger's cat paradox and the measurement problem in quantum mechanics become more apparent; with luck, trapped ion systems might be able to shed light on these fundamental issues.

  16. Ion Behavior in an Electrically Compensated Ion Cyclotron Resonance Trap

    PubMed Central

    Brustkern, Adam M.; Rempel, Don L.; Gross, Michael L.

    2010-01-01

    We recently described a new electrically compensated trap in FT ion cyclotron resonance mass spectrometry and developed a means of tuning traps of this general design. Here, we describe a continuation of that research by comparing the ion transient lifetimes and the resulting mass resolving powers and signal-to-noise (S/N) ratios that are achievable in the compensated vs. uncompensated modes of this trap. Transient lifetimes are ten times longer under the same conditions of pressure, providing improved mass resolving power and S/N ratios. The mass resolving power as a function of m/z is linear (log-log plot) and nearly equal to the theoretical maximum. Importantly, the ion cyclotron frequency as a function of ion number decreases linearly in accord with theory, unlike its behavior in the uncompensated mode. This linearity should lead to better control in mass calibration and increased mass accuracy than achievable in the uncompensated mode. PMID:21499521

  17. Trapped Ion Magnetic Resonance: Concepts and Designs

    NASA Astrophysics Data System (ADS)

    Pizarro, Pedro Jose

    A novel spectroscopy of trapped ions is proposed which will bring single-ion detection sensitivity to the observation of magnetic resonance spectra and resolve the apparent incompatibility in existing techniques between high information content and high sensitivity. Methods for studying both electron spin resonance (ESR) and nuclear magnetic resonance (NMR) are designed. They assume established techniques for trapping ions in high magnetic field and observing electrically the trapping frequencies with high resolution (<1 Hz) and sensitivity (single -ion). A magnetic bottle field gradient couples the spin and spatial motions together and leads to the small spin -dependent force on the ion exploited by Dehmelt to observe directly the perturbation of the ground-state electron's axial frequency by its spin magnetic moment. A series of fundamental innovations is described to extend magnetic resonance to molecular ions ( cong 100 amu) and nuclear magnetic moments. It is demonstrated how time-domain trapping frequency observations before and after magnetic resonance can be used to make cooling of the particle to its ground state unnecessary. Adiabatic cycling of the magnetic bottle off between detection periods is shown to be practical and to allow high-resolution magnetic resonance to be encoded pointwise as the presence or absence of trapping frequency shifts. Methods of inducing spin -dependent work on the ion orbits with magnetic field gradients and Larmor frequency irradiation are proposed which greatly amplify the attainable shifts in trapping frequency. The first proposal presented builds on Dehmelt's experiment to reveal ESR spectra. A more powerful technique for ESR is then designed where axially synchronized spin transitions perform spin-dependent work in the presence of a magnetic bottle, which also converts axial amplitude changes into cyclotron frequency shifts. The most general approach presented is a continuous Stern-Gerlach effect in which a magnetic field

  18. Ion trap simulation program, ITSIM: A powerful heuristic and predictive tool in ion trap mass spectrometry

    NASA Astrophysics Data System (ADS)

    Bui, Huy Anh

    The multi-particle simulation program, ITSIM version 4.0, takes advantage of the enhanced performance of the Windows 95 and NT operating systems in areas such as memory management, user friendliness, flexibility of graphics and speed, to investigate the motion of ions in the quadrupole ion trap. The objective of this program is to use computer simulations based on mathematical models to improve the performance of the ion trap mass spectrometer. The simulation program can provide assistance in understanding fundamental aspects of ion trap mass spectrometry, precede and help to direct the course of experiments, as well as having didactic value in elucidating and allowing visualization of ion behavior under different experimental conditions. The program uses the improved Euler method to calculate ion trajectories as numerical solutions to the Mathieu differential equation. This Windows version can simultaneously simulate the trajectories of ions with a virtually unlimited number of different mass-to-charge ratios and hence allows realistic mass spectra, ion kinetic energy distributions and other experimentally measurable properties to be simulated. The large number of simulated ions allows examination of (i) the offsetting effects of mutual ion repulsion and collisional cooling in an ion trap and (ii) the effects of higher order fields. Field inhomogeneities arising from exit holes, electrode misalignment, imperfect electrode surfaces or new trap geometries can be simulated with the program. The simulated data are used to obtain mass spectra from mass-selective instability scans as well as by Fourier transformation of image currents induced by coherently moving ion clouds. Complete instruments, from an ion source through the ion trap mass analyzer to a detector, can now be simulated. Applications of the simulation program are presented and discussed. Comparisons are made between the simulations and experimental data. Fourier transformed experiments and a novel six

  19. Linear ion trap based atomic frequency standard

    NASA Technical Reports Server (NTRS)

    Prestage, John D.; Dick, G. J.; Maleki, Lute

    1991-01-01

    In order to develop a trapped ion-based fieldable frequency standard with stability 1 x 10 to the -13th/sq rt tau for averaging times tau greater than 10,000 s, a hybrid RF/DC linear ion trap was developed which permits storage of large numbers of ions with reduced susceptibility to the second-order Doppler effect caused by the RF confining fields. The authors have confined Hg-199(+) ions in this trap and have measured very high Q transitions with good SNRs. In preliminary measurements they obtained stabilities of 1.6 x 10 to the -13th/sq rt tau (tau between 50 and 800 s) with a 160-mHz wide atomic resonance linewidth and a signal-to-noise ratio of 40 for each measurement cycle. Atomic resonance lines as narrow as 30 mHz on the 40.5-GHz clock transition have been measured with no appreciable reduction in the ion signal. A stability of 7 x 10 to the -14th/sq rt tau is made possible by the signal-to-noise and line Q of this measured transition. Analysis of fundamental sources of frequency instability indicates that a long-term stability of 2 x 10 to the -16th is feasible for this device with existing technology for tau = 10 to the 6th s or more.

  20. Development of a Kingdon ion trap system for trapping externally injected highly charged ions.

    PubMed

    Numadate, Naoki; Okada, Kunihiro; Nakamura, Nobuyuki; Tanuma, Hajime

    2014-10-01

    We have developed a Kingdon ion trap system for the purpose of the laboratory observation of the x-ray forbidden transitions of highly charged ions (HCIs). Externally injected Ar(q+) (q = 5-7) with kinetic energies of 6q keV were successfully trapped in the ion trap. The energy distribution of trapped ions is discussed in detail on the basis of numerical simulations. The combination of the Kingdon ion trap and the time-of-flight mass spectrometer enabled us to measure precise trapping lifetimes of HCIs. As a performance test of the instrument, we measured trapping lifetimes of Ar(q+) (q = 5-7) under a constant number density of H2 and determined the charge-transfer cross sections of Ar(q+)(q = 5, 6)-H2 collision systems at binary collision energies of a few eV. It was confirmed that the present cross section data are consistent with previous data and the values estimated by some scaling formula. PMID:25362383

  1. Development of a Kingdon ion trap system for trapping externally injected highly charged ions

    SciTech Connect

    Numadate, Naoki; Okada, Kunihiro; Nakamura, Nobuyuki; Tanuma, Hajime

    2014-10-01

    We have developed a Kingdon ion trap system for the purpose of the laboratory observation of the x-ray forbidden transitions of highly charged ions (HCIs). Externally injected Ar{sup q+} (q = 5–7) with kinetic energies of 6q keV were successfully trapped in the ion trap. The energy distribution of trapped ions is discussed in detail on the basis of numerical simulations. The combination of the Kingdon ion trap and the time-of-flight mass spectrometer enabled us to measure precise trapping lifetimes of HCIs. As a performance test of the instrument, we measured trapping lifetimes of Ar{sup q+} (q = 5–7) under a constant number density of H₂ and determined the charge-transfer cross sections of Ar{sup q+}(q = 5, 6)-H₂ collision systems at binary collision energies of a few eV. It was confirmed that the present cross section data are consistent with previous data and the values estimated by some scaling formula.

  2. Miniaturized Linear Wire Ion Trap Mass Analyzer.

    PubMed

    Wu, Qinghao; Li, Ailin; Tian, Yuan; Zare, Richard N; Austin, Daniel E

    2016-08-01

    We report a linear ion trap (LIT) in which the electric field is formed by fine wires held under tension and accurately positioned using holes drilled in two end plates made of plastic. The coordinates of the hole positions were optimized in simulation. The stability diagram and mass spectra using boundary ejection were compared between simulation and experiment and good agreement was found. The mass spectra from experiments show peak widths (fwhm) in units of mass-to-charge of around 0.38 Th using a scan rate of 3830 Th/s. The limits of detection are 137 ppbv and 401 ppbv for benzene and toluene, respectively. Different sizes of the wire ion trap can be easily fabricated by drilling holes in scaled positions. Other distinguishing features, such as high ion and photon transmission, low capacitance, high tolerance to mechanical and assembly error, and low weight, are discussed. PMID:27373557

  3. The trapped mercury ion frequency standard

    NASA Technical Reports Server (NTRS)

    Mcguire, M. D.

    1977-01-01

    Singly ionized mercury atoms have a structure similar to neutral alkali atoms. They can be maintained as ions for very long times in an RF quadrupole ion trap. Thus, their ground state hyperfine structure can be used to make a frequency standard using optical pumping techniques similar to the well-known rubidium standard. The mass 199 isotope of mercury has an ionic hyperfine structure of 40.5 GHz. In a trap system a linewidth of 10 Hz has been measured. An expression is presented for the short-term stability of a proposed mercury standard as set by the achieved signal to noise ratio. There is prospect of further improvement. Long-term stability is affected by second order doppler effect, and by pressure, light, and Stark shifts. However, these appear either sufficiently small or sufficiently controlable that the proposed mercury ion standard would be competitive with existing standards.

  4. Proposed LLNL electron beam ion trap

    SciTech Connect

    Marrs, R.E.; Egan, P.O.; Proctor, I.; Levine, M.A.; Hansen, L.; Kajiyama, Y.; Wolgast, R.

    1985-07-02

    The interaction of energetic electrons with highly charged ions is of great importance to several research fields such as astrophysics, laser fusion and magnetic fusion. In spite of this importance there are almost no measurements of electron interaction cross sections for ions more than a few times ionized. To address this problem an electron beam ion trap (EBIT) is being developed at LLNL. The device is essentially an EBIS except that it is not intended as a source of extracted ions. Instead the (variable energy) electron beam interacting with the confined ions will be used to obtain measurements of ionization cross sections, dielectronic recombination cross sections, radiative recombination cross sections, energy levels and oscillator strengths. Charge-exchange recombinaion cross sections with neutral gasses could also be measured. The goal is to produce and study elements in many different charge states up to He-like xenon and Ne-like uranium. 5 refs., 2 figs.

  5. The JPL trapped mercury ion frequency standard

    NASA Technical Reports Server (NTRS)

    Prestage, J. D.; Dick, G. J.; Maleki, L.

    1988-01-01

    In order to provide frequency standards for the Deep Space Network (DSN) which are more stable than present-day hydrogen masers, a research task was established under the Advanced Systems Program of the TDA to develop a Hg-199(+) trapped ion frequency standard. The first closed-loop operation of this kind is described. Mercury-199 ions are confined in an RF trap and are state-selected through the use of optical pumping with 194 nm UV light from a Hg-202 discharge lamp. Absorption of microwave radiation at the hyperfine frequency (40.5 GHz) is signaled by atomic fluorescence of the UV light. The frequency of a 40.5 GHz oscillator is locked to a 1.6 Hz wide atomic absorption line of the trapped ions. The measured Allan variance of this locked oscillator is currently gamma sub y (pi) = 4.4 x 10 to the minus 12th/square root of pi for 20 is less than pi is less than 320 seconds, which is better stability than the best commercial cesium standards by almost a factor of 2. This initial result was achieved without magnetic shielding and without regulation of ion number.

  6. Fundamentals of Trapped Ion Mobility Spectrometry

    NASA Astrophysics Data System (ADS)

    Michelmann, Karsten; Silveira, Joshua A.; Ridgeway, Mark E.; Park, Melvin A.

    2015-01-01

    Trapped ion mobility spectrometry (TIMS) is a relatively new gas-phase separation method that has been coupled to quadrupole orthogonal acceleration time-of-flight mass spectrometry. The TIMS analyzer is a segmented rf ion guide wherein ions are mobility-analyzed using an electric field that holds ions stationary against a moving gas, unlike conventional drift tube ion mobility spectrometry where the gas is stationary. Ions are initially trapped, and subsequently eluted from the TIMS analyzer over time according to their mobility ( K). Though TIMS has achieved a high level of performance ( R > 250) in a small device (<5 cm) using modest operating potentials (<300 V), a proper theory has yet to be produced. Here, we develop a quantitative theory for TIMS via mathematical derivation and simulations. A one-dimensional analytical model, used to predict the transit time and theoretical resolving power, is described. Theoretical trends are in agreement with experimental measurements performed as a function of K, pressure, and the axial electric field scan rate. The linear dependence of the transit time with 1/ K provides a fundamental basis for determination of reduced mobility or collision cross section values by calibration. The quantitative description of TIMS provides an operational understanding of the analyzer, outlines the current performance capabilities, and provides insight into future avenues for improvement.

  7. Quantum information processing with trapped ion chains

    NASA Astrophysics Data System (ADS)

    Manning, Timothy Andrew

    Trapped atomic ion systems are currently the most advanced platform for quantum information processing. Their long coherence times, pristine state initialization and detection, and precisely controllable and versatile interactions make them excellent quantum systems for experiments in quantum computation and quantum simulation. One of the more promising schemes for quantum computing consists of performing single and multi-qubit quantum gates on qubits in a linear ion crystal. Some of the key challenges of scaling such a system are the individual addressing of arbitrary subsets of ions and controlling the growing complexity of motional mode interactions as the number of qubits increases or when the gates are performed faster. Traditional entangling quantum gates between ion qubits use laser pulses to couple the qubit states to the collective motion of the crystal, thereby generating a spin-spin interaction that can produce entanglement between selected qubits. The intrinsic limitations on the performance of gates using this method can be alleviated by applying optimally shaped pulses instead of pulses with constant amplitude. This thesis explains the theory behind this pulse shaping scheme and how it is implemented on a chain of Yb ions held in a linear radiofrequency 'Paul' trap. Several experiments demonstrate the technique in chains of two, three, and five ions using various types of pulse shapes. A tightly focused individual addressing beam allows us to apply the entangling gates to a target pair of ions, and technical issues related to such tight focusing are discussed. Other advantages to the pulse shaping scheme include a robustness against detuning errors and the possibility of suppressing undesirable coupling due to optical spillover on neighboring ions. Combined with ion shuttling, we harness these features to perform sequential gates to different qubit pairs in order to create genuine tripartite entangled states and demonstrate the programmable quantum

  8. Trapped Ion Quantum Computation by Adiabatic Passage

    SciTech Connect

    Feng Xuni; Wu Chunfeng; Lai, C. H.; Oh, C. H.

    2008-11-07

    We propose a new universal quantum computation scheme for trapped ions in thermal motion via the technique of adiabatic passage, which incorporates the advantages of both the adiabatic passage and the model of trapped ions in thermal motion. Our scheme is immune from the decoherence due to spontaneous emission from excited states as the system in our scheme evolves along a dark state. In our scheme the vibrational degrees of freedom are not required to be cooled to their ground states because they are only virtually excited. It is shown that the fidelity of the resultant gate operation is still high even when the magnitude of the effective Rabi frequency moderately deviates from the desired value.

  9. Single-trapped-ion vibronic Raman laser

    NASA Astrophysics Data System (ADS)

    di Fidio, C.; Vogel, W.; de Matos Filho, R. L.; Davidovich, L.

    2002-01-01

    We propose a model for a single-trapped-ion vibronic Raman laser and study its dynamics by using quantum-trajectory methods. In our treatment, it is essential that both the cavity field of the high-finesse optical cavity and the center-of-mass vibrational motion of the trapped ion be quantized. A transition from a super-Poissonian light source to a Poissonian lasing regime is obtained by increasing the Raman coupling constant. Furthermore, we demonstrate that a nonclassical regime can be realized, where the photon statistics becomes sub-Poissonian and the photons leak out of the cavity in an antibunched manner. This is achieved by exploiting nonlinear Stark shifts inherent in the model, which depend on both the number of cavity photons and the number of vibrational quanta.

  10. Quantum Rabi Model with Trapped Ions

    PubMed Central

    Pedernales, J. S.; Lizuain, I.; Felicetti, S.; Romero, G.; Lamata, L.; Solano, E.

    2015-01-01

    We propose the quantum simulation of the quantum Rabi model in all parameter regimes by means of detuned bichromatic sideband excitations of a single trapped ion. We show that current setups can reproduce, in particular, the ultrastrong and deep strong coupling regimes of such a paradigmatic light-matter interaction. Furthermore, associated with these extreme dipolar regimes, we study the controlled generation and detection of their entangled ground states by means of adiabatic methods. Ion traps have arguably performed the first quantum simulation of the Jaynes-Cummings model, a restricted regime of the quantum Rabi model where the rotating-wave approximation holds. We show that one can go beyond and experimentally investigate the quantum simulation of coupling regimes of the quantum Rabi model that are difficult to achieve with natural dipolar interactions. PMID:26482660

  11. Quantum Rabi Model with Trapped Ions.

    PubMed

    Pedernales, J S; Lizuain, I; Felicetti, S; Romero, G; Lamata, L; Solano, E

    2015-01-01

    We propose the quantum simulation of the quantum Rabi model in all parameter regimes by means of detuned bichromatic sideband excitations of a single trapped ion. We show that current setups can reproduce, in particular, the ultrastrong and deep strong coupling regimes of such a paradigmatic light-matter interaction. Furthermore, associated with these extreme dipolar regimes, we study the controlled generation and detection of their entangled ground states by means of adiabatic methods. Ion traps have arguably performed the first quantum simulation of the Jaynes-Cummings model, a restricted regime of the quantum Rabi model where the rotating-wave approximation holds. We show that one can go beyond and experimentally investigate the quantum simulation of coupling regimes of the quantum Rabi model that are difficult to achieve with natural dipolar interactions. PMID:26482660

  12. Quantum error correction with trapped ions

    NASA Astrophysics Data System (ADS)

    Schindler, Philipp

    Quantum computers promise exponential speed-up compared to their classical counterparts for certain problems. Unfortunately, the states required for quantum computation are fragile and lose their quantum properties with growing system size. In a milestone work, it has been shown that quantum error correction can overcome this problem and enable arbitrary long and arbitrary high quality quantum algorithms. However, current experiments are not able to fulfill the requirements to employ useful quantum error correction procedures. In this talk, I will first review past proof-of-principle experiments in trapped ion quantum information processors. Building on that, I will sketch a way towards a medium-sized trapped ion system that will be capable of running an error correction procedure that outperforms it constituents.

  13. Ultrafast Interferometry and Gates with Trapped Ions

    NASA Astrophysics Data System (ADS)

    Johnson, Kale; Wong-Campos, David; Neyenhuis, Brian; Mizrahi, Jonathan; Monroe, Christopher

    2016-05-01

    We sense the motion of a trapped atomic ion using a sequence of state-dependent ultrafast momentum kicks. We use this atom interferometer to characterize a nearly-pure quantum state with n = 1 phonon and accurately measure thermal states ranging from near the zero-point energy to n ~104 , with the possibility of extending at least 100 times higher in energy. The complete energy range of this method spans from the ground state to far outside of the Lamb-Dicke regime, where atomic motion is greater than the optical wavelength. Apart from thermometry, these interferometric techniques are useful for quantum information purposes, and we discuss the outlook for ultrafast entangling gates between multiple trapped ions. This work is supported by the NSF Physics Frontier Center at JQI.

  14. Quantum Information Processing with Trapped Ions

    SciTech Connect

    Barrett, M.D.; Schaetz, T.; Chiaverini, J.; Leibfried, D.; Britton, J.; Itano, W.M.; Jost, J.D.; Langer, C.; Ozeri, R.; Wineland, D.J.; Knill, E.

    2005-05-05

    We summarize two experiments on the creation and manipulation of multi-particle entangled states of trapped atomic ions - quantum dense coding and quantum teleportation. The techniques used in these experiments constitute an important step toward performing large-scale quantum information processing. The techniques also have application in other areas of physics, providing improvement in quantum-limited measurement and fundamental tests of quantum mechanical principles, for example.

  15. An improved linear ion trap physics package

    NASA Technical Reports Server (NTRS)

    Prestage, J. D.

    1993-01-01

    This article describes an improvement in the architecture of the physics package used in the Linear Ion Trap (LIT)-based frequency standard recently developed at JPL. This new design is based on the observation that ions can be moved along the axis of an LIT by applied dc voltages. The state selection and interrogation region can be separated from the more critical microwave resonance region where the multiplied local oscillator signal is compared with the stable atomic transition. This separation relaxes many of the design constraints of the present units. Improvements include increased frequency stability and a substantial reduction in size, mass, and cost of the final frequency standard.

  16. Note: Ion source design for ion trap systems

    NASA Astrophysics Data System (ADS)

    Noriega, J. R.; Quevedo, M.; Gnade, B.; Vasselli, J.

    2013-06-01

    A small plasma (glow discharge) based ion source and circuit are described in this work. The ion source works by producing a high voltage pulsed discharge between two electrodes in a pressure range of 50-100 mTorr. A third mesh electrode is used for ion extraction. The electrodes are small stainless steel screws mounted in a MACOR ionization chamber in a linear arrangement. The electrode arrangement is driven by a circuit, design for low power operation. This design is a proof of concept intended for applications on small cylindrical ion traps.

  17. ION TRAPPING AND CATHODE BOMBARDMENT BY TRAPPED IONS IN DC PHOTOGUNS.

    SciTech Connect

    POZDEYEV,E.

    2007-06-25

    DC photoguns are used to produce high-quality, high-intensity electron beams for accelerator driven applications. Ion bombardment is believed to be the major cause of degradation of the photocathode efficiency. Additionally to ions produced in the accelerating cathode-anode gap, the electron beam can ionize the residual gas in the transport line. These ions are trapped transversely within the beam and can drift back to the accelerating gap and contribute to the bombardment rate of the cathode. This paper proposes a method to reduce the flow of ions produced in the beam transport line and drifting back to the cathode-anode gap by introducing a positive potential barrier that repels the trapped ions. The reduced ion bombardment rate and increased life time of photocathodes will reduce the downtime required to service photoinjectors and associated costs.

  18. Three-Dimensional Array for 40Ca+ Ion Trapping

    NASA Astrophysics Data System (ADS)

    Wan, Jin-Yin; Liu, Liang

    2009-04-01

    We present a three-dimensional scalable linear ion trap scheme for ion trapping and discuss its applications for the optical frequency standard and scalable quantum information processing with its parallel strings of trapped 40Ca+ ions. The geometry here contains nine equal-distance parallel rods driven by rf, which form trapping potentials for radial confinement and two end ring electrodes biased at a few volts for axial confinement. Its feasibility is calculated by using the finite element analysis method.

  19. Progress Toward a Cold Ion Interferometer

    NASA Astrophysics Data System (ADS)

    Archibald, James; Christopher, Erickson; Jackson, Jarom; Durfee, Dallin

    2012-06-01

    We describe progress on a cold ion matter-wave interferometer. The ions are generated by laser-cooling strontium and then photo-ionizing the atoms with a two-photon transition to an auto- ionizing state in the continuum. Each ion's quantum wave will be split and recombined using stimulated Raman transitions between the hyperfine ground states of Sr^87+. The interferometer phase will be determined by measuring the fraction of ions exiting in each hyperfine state. We will discuss the theory of operation, experimental methods, and potential applications of the device.

  20. Spectroscopy of ions using fast beams and ion traps

    SciTech Connect

    Pinnington, E H; Trabert, E

    2004-10-01

    A knowledge of the spectra of ionized atoms is of importance in many fields. They can be studied in a wide variety of light sources. In recent years techniques coming under the broad heatings of fast beams and ion traps have been used extensively for such investigations. This article considers the advantages that various techniques have for particular applications.

  1. Ultrafast Manipulation of Trapped Ion Qubits

    NASA Astrophysics Data System (ADS)

    Campbell, Wes; Quraishi, Qudsia; Mizrahi, Jonathan; Monroe, Chris

    2009-05-01

    Ultrashort light pulses are an attractive tool for trapped ion quantum information processing. High pulse intensity permits far-detuned (>10 nm) operation, where decoherence from differential AC Stark shifts and spontaneous emission is suppressed. Short pulse duration allows interaction times shorter than a trap oscillation, circumventing the need for cooling to the Lamb-Dicke limit. We describe an experiment with trapped ^171Yb^+ using a vanadate laser (˜10 ps pulses at 355 nm). Since the single pulse bandwidth exceeds the S1/2 hyperfine splitting, coherent Raman transitions between qubit states should be possible. This is in contrast to our previous work [1] with near-resonant pulses that coherently transfer population to the P-state. It should also be possible to use a series of multiple pulses to impart spin-dependent forces. By controlling the pulse timing and phase we could then entangle multiple ions in a temperature insensitive manner [2,3]. [1] Madsen et al., PRL 97, 040505 (2006). [2] Garc'ia-Ripoll et al., PRL 91, 157901 (2003). [3] Duan, PRL 93, 100502 (2004).

  2. Prospects for quantum computation with trapped ions

    SciTech Connect

    Hughes, R.J.; James, D.F.V.

    1997-12-31

    Over the past decade information theory has been generalized to allow binary data to be represented by two-state quantum mechanical systems. (A single two-level system has come to be known as a qubit in this context.) The additional freedom introduced into information physics with quantum systems has opened up a variety of capabilities that go well beyond those of conventional information. For example, quantum cryptography allows two parties to generate a secret key even in the presence of eavesdropping. But perhaps the most remarkable capabilities have been predicted in the field of quantum computation. Here, a brief survey of the requirements for quantum computational hardware, and an overview of the in trap quantum computation project at Los Alamos are presented. The physical limitations to quantum computation with trapped ions are discussed.

  3. Electron beam ion sources and traps (invited)

    NASA Astrophysics Data System (ADS)

    Becker, Reinard

    2000-02-01

    The electron beam method of stepwise ionization to highest charge states has found applications in electron beam ion sources (EBISs) for accelerators and atomic physics collision experiments as well as in electron beam ion traps (EBITs) for x-ray and mass spectroscopy. A dense and almost monoenergetic electron beam provides a unique tool for ionization, because radiative recombination by slow electrons is negligible and charge exchange is almost avoided in ultrahigh vacua. These are essential differences to electron cyclotron resonance ion sources with inevitable low energy electrons and comparatively high gas pressure. The distinction between EBIS and EBIT as genuine devices has become meaningless, because EBISs may work as traps and almost all EBITs are feeding beamlines for external experiments. More interesting is to note the diversification of these devices, which demonstrates that a matured technology is finding dedicated answers for different applications. At present we may distinguish six major lines of development and application: high current EBISs for upcoming hadron colliders, super EBITs in the energy range above 300 keV for quantum electrondynamics tests, inexpensive and small EBISTs for atomic physics studies, a highly efficient EBIS with oscillating electrons, MEDEBIS for tumor therapy with C6+, and charge breeding in facilities for exotic radioactive beams.

  4. Ball-grid array architecture for microfabricated ion traps

    SciTech Connect

    Guise, Nicholas D. Fallek, Spencer D.; Stevens, Kelly E.; Brown, K. R.; Volin, Curtis; Harter, Alexa W.; Amini, Jason M.; Higashi, Robert E.; Lu, Son Thai; Chanhvongsak, Helen M.; Nguyen, Thi A.; Marcus, Matthew S.; Ohnstein, Thomas R.; Youngner, Daniel W.

    2015-05-07

    State-of-the-art microfabricated ion traps for quantum information research are approaching nearly one hundred control electrodes. We report here on the development and testing of a new architecture for microfabricated ion traps, built around ball-grid array (BGA) connections, that is suitable for increasingly complex trap designs. In the BGA trap, through-substrate vias bring electrical signals from the back side of the trap die to the surface trap structure on the top side. Gold-ball bump bonds connect the back side of the trap die to an interposer for signal routing from the carrier. Trench capacitors fabricated into the trap die replace area-intensive surface or edge capacitors. Wirebonds in the BGA architecture are moved to the interposer. These last two features allow the trap die to be reduced to only the area required to produce trapping fields. The smaller trap dimensions allow tight focusing of an addressing laser beam for fast single-qubit rotations. Performance of the BGA trap as characterized with {sup 40}Ca{sup +} ions is comparable to previous surface-electrode traps in terms of ion heating rate, mode frequency stability, and storage lifetime. We demonstrate two-qubit entanglement operations with {sup 171}Yb{sup +} ions in a second BGA trap.

  5. Adjustable microchip ring trap for cold atoms and molecules

    SciTech Connect

    Baker, Paul M.; Stickney, James A.; Squires, Matthew B.; Scoville, James A.; Carlson, Evan J.; Buchwald, Walter R.; Miller, Steven M.

    2009-12-15

    We describe the design and function of a circular magnetic waveguide produced from wires on a microchip for atom interferometry using de Broglie waves. The guide is a two-dimensional magnetic minimum for trapping weak-field seeking states of atoms or molecules with a magnetic dipole moment. The design consists of seven circular wires sharing a common radius. We describe the design, the time-dependent currents of the wires and show that it is possible to form a circular waveguide with adjustable height and gradient while minimizing perturbation resulting from leads or wire crossings. This maximal area geometry is suited for rotation sensing with atom interferometry via the Sagnac effect using either cold atoms, molecules and Bose-condensed systems.

  6. Lunar Polar Cold Traps: Spatial Distribution and Temperatures

    NASA Astrophysics Data System (ADS)

    Paige, David A.; Siegler, M.; Lawrence, D. J.

    2006-09-01

    We have developed a ray-tracing and radiosity model that can accurately calculate lunar surface and subsurface temperatures for arbitrary topography. Using available digital elevation models for the lunar north and south polar regions derived from Clementine laser altimeter and image data, as well as ground-based radar data, we have calculated lunar surface and subsurface temperatures at 2 km resolution that include full effects of indirect solar and infrared radiation due to topography. We compare our thermal model results with maps of epithermal neutron flux measured by Lunar Prospector. When we use the ray tracing and thermal model to account for the effects of temperature and topography on the neutron measurements, our results show that the majority of the moon's polar cold traps are not filled with water ice.

  7. Ion dynamics in a trapped ion mobility spectrometer†

    PubMed Central

    Hernandez, Diana Rosa; DeBord, John Daniel; Ridgeway, Mark E.; Kaplan, Desmond A.; Park, Melvin A.; Fernandez-Lima, Francisco

    2014-01-01

    In the present paper, theoretical simulations and experimental observations are used to describe the ion dynamics in a trapped ion mobility spectrometer. In particular, the ion motion, ion transmission and mobility separation are discussed as a function of the bath gas velocity, radial confinement, analysis time and speed. Mobility analysis and calibration procedure are reported for the case of sphere-like molecules for positive and negative ion modes. Results showed that a maximal mobility resolution can be achieved by optimizing the gas velocity, radial confinement (RF amplitude) and ramp speed (voltage range and ramp time). The mobility resolution scales with the electric field and gas velocity and R = 100–250 can be routinely obtained at room temperature. PMID:24571000

  8. Progress Towards Quantum Simulation Using Micro-fabricated Ion Traps

    NASA Astrophysics Data System (ADS)

    Wright, K.; Ji, G.; Rickerd, C.; Collins, K.; Monroe, C.

    2015-05-01

    We report on current experimental progress towards using a surface electrode trap for quantum simulation. We use a micro-fabricated trap developed collaboratively between the Georgia Tech Research Institute (GTRI) and Honeywell International known as the Ball Grid Array (BGA) trap. This trap features 96 electrodes for fine control of the DC potential as well as a small footprint allowing for tight focusing of interaction lasers. We discuss the experimental system which utilizes the BGA trap, loading of Yb171 ions in this trap, and deterministic loading of chains of five or more ions. We hope to take advantage of the features of this new trap architecture in order to perform a small scale Boson Sampling experiment. This work is performed in collaboration with the GTRI Ion Trap Group and supported by ARO with funding from the IARPA MQCO program, and the AFOSR STTR on Atom Trap Chips.

  9. Design Optimization for Anharmonic Linear Surface-Electrode Ion Trap

    NASA Astrophysics Data System (ADS)

    Liu, Wei; Chen, Shu-Ming; Chen, Ping-Xing; Wu, Wei

    2014-11-01

    An accurate and rapid method is proposed to optimize anharmonic linear surface-electrode ion trap design. Based on the method, we analyze the impact of the architectural parameters, including the width, number, and applied voltage of prerequisite active electrodes, on the number and spacing of trapped ions. Sets of optimal anharmonic trap design are given. Then the optimal designs are verified by using an ant colony optimization algorithm. The results show that the maximum ion position errors and maximum ion spacing errors are less than 1 μm up to 80. The mean of the maximum errors is nearly linear with respect to the number of trapped ions.

  10. Ion beam analysis of defect trapping

    NASA Astrophysics Data System (ADS)

    Swanson, M. L.; Howe, L. M.

    1983-12-01

    Channeling measurements using medium energy ions (e.g. 1 MeV He +) have been used to determine the positions of solute atoms which are displaced from lattice sites by the trapping of vacancies and self-interstitial atoms. In this way, some simple defect trapping configurations have been identified in fcc metals. One of these is the mixed dumbbell (created when a self-interstitial is trapped by a small solute atom), consisting of a host atom and solute atom stradding a normal lattice site. Another is the tetravacancy-solute atom complex, consisting of four nearest neighbour vacancies surrounding a solute atom displaced into the tetrahedral interstitial site. In addition, from detailed analyses of displacements into different crystallographic channels as a function of irradiation fluence and annealing temperature, the evolution of a variety of defect complexes containing self-interstitials or vacancies has been studied in Al, Cu, Ni, Fe, and Mg crystals. Information from channeling analyses will be compared with data obtained from measurements of electrical resistivity, Mössbauer effect, perturbed angular correlation, extended X-ray absorption fine structure, muon precession, positron annihilation and internal friction. The advantages of the different methods will be discussed.

  11. Toward spin squeezing with trapped ions

    NASA Astrophysics Data System (ADS)

    Uys, Hermann; Biercuk, Michael; Britton, Joe; Bollinger, John J.

    2012-09-01

    Building robust instruments capable ofmaking interferometric measurements with precision beyond the standard quantum limit remains an important goal in many metrology laboratories. We describe here the basic concepts underlying spin squeezing experiments that allow one to surpass this limit. In principle it is possible to reach the so-called Heisenberg limit, which constitutes an improvement in precision by a factorv √N , where N is the number of particles on which the measurement is carried out. In particular, we focus on recent progress toward implementing spin squeezing with a cloud of beryllium ions in a Penning ion trap, via the geometric phase gate used more commonly for performing two-qubit entangling operations in quantum computing experiments.

  12. New ion trap for atomic frequency standard applications

    NASA Technical Reports Server (NTRS)

    Prestage, J. D.; Dick, G. J.; Maleki, L.

    1989-01-01

    A novel linear ion trap that permits storage of a large number of ions with reduced susceptibility to the second-order Doppler effect caused by the radio frequency (RF) confining fields has been designed and built. This new trap should store about 20 times the number of ions a conventional RF trap stores with no corresponding increase in second-order Doppler shift from the confining field. In addition, the sensitivity of this shift to trapping parameters, i.e., RF voltage, RF frequency, and trap size, is greatly reduced.

  13. Integrated Diffractive Optics for Surface Ion Traps

    NASA Astrophysics Data System (ADS)

    Streed, Erik; Ghadimi, Moji; Blums, Valdis; Norton, Benjamin; Connor, Paul; Amini, Jason; Volin, Curtis; Lobino, Mirko; Kielpinski, David

    2016-05-01

    Photonic interconnects are a bottleneck to achieving large-scale trapped ion quantum computing. We have modified a Georgia Tech Research Institute microwave chip trap by using e-beam lithography to write reflective diffractive collimating optics (80 μm x 127 μm, f=58.6 μm, λ=369.5nm) on the center electrode. The optics have an NA of 0.55 x 0.73, capturing 13.2% of the solid angle. To evaluate the optics 174Yb+ was loaded by isotope selective photo-ionization from a thermal oven and then shuttled to imaging sites. Near diffraction limited sub-wavelength ion images were obtained with an observed spot sized FWHM of 338 nm x 268 nm vs. a diffraction limit of 336 nm x 257 nm. The total photon collection efficiency was measured to be 5.2+/-1.2%. Coupling into a single mode fiber of up to 2.0+/-0.6% was observed, limited by mismatch in the coupling optics. Image mode quality indicates coupling up to 4% may be possible. Funding from Australian Research Council and IARPA.

  14. Computer simulations of ions in radio-frequency traps

    NASA Technical Reports Server (NTRS)

    Williams, A.; Prestage, J. D.; Maleki, L.; Djomehri, J.; Harabetian, E.

    1990-01-01

    The motion of ions in a trapped-ion frequency standard affects the stability of the standard. In order to study the motion and structures of large ion clouds in a radio-frequency (RF) trap, a computer simulation of the system that incorporates the effect of thermal excitation of the ions was developed. Results are presented from the simulation for cloud sizes up to 512 ions, emphasizing cloud structures in the low-temperature regime.

  15. Ultra-stable Hg(+) trapped ion frequency standard

    NASA Technical Reports Server (NTRS)

    Prestage, John D.; Dick, G. John; Maleki, Lute

    1990-01-01

    A fieldable trapped ion frequency standard based on Hg-199(+) ions confined in a hybrid rf/dc linear ion trap is developed. This trap permits storage of large numbers of ions with reduced susceptibility to the second-order Doppler effect caused by the rf confining fields. In preliminary measurements a stability of 2 to 3 x 10(exp -15) was obtained for 10000 second averaging times. These measurements were carried out with a 120 mHz wide atomic resonance line for the 40.5 GHz clock transition with a second order Doppler shift from the rf trapping field of 6 x 10(exp -13).

  16. Trap door and underside of cap stone of pyramid ion ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Trap door and underside of cap stone of pyramid ion - Washington Monument, High ground West of Fifteenth Street, Northwest, between Independence & Constitution Avenues, Washington, District of Columbia, DC

  17. Cold Ion Escape from the Martian Ionosphere

    NASA Astrophysics Data System (ADS)

    Fränz, Markus; Dubinin, Eduard; Andrews, David; Nilsson, Hans; Fedorov, Andrei

    2014-05-01

    It has always been challenging to observe the flux of ions with energies of less than 10eV escaping from the planetary ionospheres. We here report on new measurements of the ionospheric ion flows at Mars by the ASPERA-3 experiment on board Mars Express. The ion sensor IMA of this experiment has in principle a low-energy cut-off at 10eV but in negative spacecraft charging cold ions are lifted into the range of measurement but the field of view is restricted to about 4x360 deg. In a recent paper Nilsson et al. (Earth Planets Space, 64, 135, 2012) tried to use the method of long-time averaged distribution functions to overcome these constraints. In this paper we first use the same method to show that we get results consistent with this when using ASPERA-3 observations only. But then we can show that these results are inconsistent with observations of the local plasma density by the MARSIS radar instrument on board Mars Express. We demonstrate that the method of averaged distribution function can deliver the mean flow speed of the plasma but the low-energy cut-off does usually not allow to reconstruct the density. We then combine measurements of the cold ion flow speed with the plasma density observations of MARSIS to derive the cold ion flux. In an analysis of the combined nightside datasets we show that the main escape channel is along the shadow boundary on the tailside of Mars. At a distance of about 0.5 Martian radii the flux settles at a constant value which indicates that about half of the transterminator ionospheric flow escapes from the planet. Possible mechanism to generate this flux can be the ionospheric pressure gradient between dayside and nightside or momentum transfer from the solar wind via the induced magnetic field since the flow velocity is in the Alfvénic regime.

  18. Cold ion escape from the Martian ionosphere

    NASA Astrophysics Data System (ADS)

    Fränz, M.; Dubinin, E.; Andrews, D.; Barabash, S.; Nilsson, H.; Fedorov, A.

    2015-12-01

    We here report on new measurements of the escape flux of oxygen ions from Mars by combining the observations of the ASPERA-3 and MARSIS experiments on board the European Mars Express spacecraft. We show that in previous estimates of the total heavy ion escape flow the contribution of the cold ionospheric outflow with energies below 10 eV has been underestimated. Both case studies and the derived flow pattern indicate that the cold plasma observed by MARSIS and the superthermal plasma observed by ASPERA-3 move with the same bulk speed in most regions of the Martian tail. We determine maps of the tailside heavy ion flux distribution derived from mean ion velocity distributions sampled over 7 years. If we assume that the superthermal bulk speed derived from these long time averages of the ion distribution function represent the total plasma bulk speed we derive the total tailside plasma flux. Assuming cylindrical symmetry we determine the mean total escape rate for the years 2007-2014 at 2.8 ± 0.4 ×1025 atoms / s which is in good agreement with model estimates. A possible mechanism to generate this flux can be the ionospheric pressure gradient between dayside and nightside.

  19. Nonlinear theory of collisionless trapped ion modes

    SciTech Connect

    Hahm, T.S.; Tang, W.M.

    1996-03-01

    A simplified two field nonlinear model for collisionless trapped-ion-mode turbulence has been derived from nonlinear bounce-averaged drift kinetic equations. The renormalized thermal diffusivity obtained from this analysis exhibits a Bohm-like scaling. A new nonlinearity associated with the neoclassical polarization density is found to introduce an isotope-dependent modification to this Bohm-like diffusivity. The asymptotic balance between the equilibrium variation and the finite banana width induced reduction of the fluctuation potential leads to the result that the radial correlation length decreases with increasing plasma current. Other important conclusions from the present analysis include the predictions that (i) the relative density fluctuation level {delta}n/n{sub 0} is lower than the conventional mixing length estimate, {Delta}r/L{sub n} (ii) the ion temperature fluctuation level {delta}T{sub i}/T{sub i} significantly exceeds the density fluctuation level {delta}n/n{sub 0}; and (iii) the parallel ion velocity fluctuation level {delta}v{sub i}{sub {parallel}}/v{sub Ti} is expected to be negligible.

  20. Test of Lorentz symmetry with trapped ions

    NASA Astrophysics Data System (ADS)

    Pruttivarasin, Thaned

    2016-05-01

    The outcome of an experiment should not depend on the orientation of the apparatus in space. This important cornerstone of physics is deeply engrained into the Standard Model of Physics by requiring that all fields must be Lorentz invariant. However, it is well-known that the Standard Model is incomplete. Some theories conjecture that at the Planck scale Lorentz symmetry might be broken and measurable at experimentally accessible energy scales. Therefore, a search for violation of Lorentz symmetry directly probes physics beyond the Standard model. We present a novel experiment utilizing trapped calcium ions as a direct probe of Lorentz-violation in the electron-photon sector. We monitor the energy between atomic states with different orientations of the electronic wave-functions as they rotate together with the motion of the Earth. This is analogous to the famous Michelson-Morley experiment. To remove magnetic field noise, we perform the experiment with the ions prepared in the decoherence-free states. Our result improves on the most stringent bounds on Lorentz symmetry for electrons by 100 times. The experimental scheme is readily applicable to many ion species, hence opening up paths toward much improved test of Lorentz symmetry in the future. (Ph. D. Advisor: Hartmut Haeffner, University of California, Berkeley).

  1. An Atomic Abacus: Trapped ion quantum computing experiments at NIST

    NASA Astrophysics Data System (ADS)

    Demarco, Brian

    2003-03-01

    Trapped atomic ions are an ideal system for exploring quantum information science because deterministic state preparation and efficient state detection are possible and coherent manipulation of atomic systems is relatively advanced. In our experiment, a few singly charged Be ions are confined by static and radio-frequency electric fields in a micro-machined linear Paul trap. The internal and motional states of the ions are coherently manipulated using applied laser light. Our current work focuses on demonstrating the necessary ingredients to produce a scalable quantum computing scheme and on simplifying and improving quantum logic gates. I will speak about a new set of experiments that was made possible by recent improvements in trap technology. A novel trap with multiple trapping regions was used to demonstrate the first steps towards a fully scalable quantum computing scheme. Single ions were ``shuttled" between trapping regions without disturbing the ion's motional and internal state, and two ions were separated from a single to two different trapping zones. Improvements in the trap manufacturing process has led to a reduction of nearly two orders of magnitude in the ion's motional heating rate, making possible two new improved logic gates. The first gate utilizes the wave-packet nature of the ions to tune the laser-atom interaction and achieve a controlled-NOT gate between a single ion's spin and motional states. The second, a two-ion phase gate, uses phase-space dynamics to produce a state-sensitive geometric phase. I will end with a quick look at experiments using a Mg ion to sympathetically cool a simultaneously trapped Be ion and a glimpse of the next generation of ions traps currently under construction.

  2. Ejection of Coulomb Crystals from a Linear Paul Ion Trap for Ion-Molecule Reaction Studies.

    PubMed

    Meyer, K A E; Pollum, L L; Petralia, L S; Tauschinsky, A; Rennick, C J; Softley, T P; Heazlewood, B R

    2015-12-17

    Coulomb crystals are being increasingly employed as a highly localized source of cold ions for the study of ion-molecule chemical reactions. To extend the scope of reactions that can be studied in Coulomb crystals-from simple reactions involving laser-cooled atomic ions, to more complex systems where molecular reactants give rise to multiple product channels-sensitive product detection methodologies are required. The use of a digital ion trap (DIT) and a new damped cosine trap (DCT) are described, which facilitate the ejection of Coulomb-crystallized ions onto an external detector for the recording of time-of-flight (TOF) mass spectra. This enables the examination of reaction dynamics and kinetics between Coulomb-crystallized ions and neutral molecules: ionic products are typically cotrapped, thus ejecting the crystal onto an external detector reveals the masses, identities, and quantities of all ionic species at a selected point in the reaction. Two reaction systems are examined: the reaction of Ca(+) with deuterated isotopologues of water, and the charge exchange between cotrapped Xe(+) with deuterated isotopologues of ammonia. These reactions are examples of two distinct types of experiment, the first involving direct reaction of the laser-cooled ions, and the second involving reaction of sympathetically-cooled heavy ions to form a mixture of light product ions. Extensive simulations are conducted to interpret experimental results and calculate optimal operating parameters, facilitating a comparison between the DIT and DCT approaches. The simulations also demonstrate a correlation between crystal shape and image shape on the detector, suggesting a possible means for determining crystal geometry for nonfluorescing ions. PMID:26406306

  3. Doppler Sideband Spectra for Ions in a Linear Trap

    NASA Technical Reports Server (NTRS)

    Prestage, J. D.; Tjoelker, R. L.; Dick, G. J.; Maleki, L.

    1993-01-01

    We describe a spectroscopic measurement of the temperature and linear density of HG+ ions held in a linear ion trap (LIT). The inferred temperature and number result from analysis of sidebands on the 40.5 GHz resonance line.

  4. Progress Towards Quantum Simulation Using Micro-fabricated Ion Traps

    NASA Astrophysics Data System (ADS)

    Wright, K.; Cao, C.; Ji, G.; Brennan, T.; Monroe, C.

    2014-05-01

    We report our current experimental progress towards using surface electrode traps for quantum simulation. Current progress is being made using a micro-fabricated Satellite trap from GTRI. This trap features two long storage arms which can be used to hold ions in reserve to mitigate the need to load ions via a heated oven in the event of ion loss. This should allow trapping of long ion chains with a substantial decrease in the time needed to recover an ion chain of a given length. The trap has 96 electrodes for fine control of the DC potential needed to create large anharmonic trapping wells. It also features two crossing linear regions for the ordering of mixed ion chains by selective shuttling between the arms of intersecting linear regions of the trap. This should allow us to trap multiple species and explore the advantages of having sympathetic coolant ions. Interspersing these ions through a chain of ions undergoing coherent operations potentially could increase the chain lifetime as well as mitigate certain heating effects. We hope to use these features as the next step in increasing the size of current quantum simulations being done at UMD, which are aimed at exploring quantum phenomena in spin systems. In collaboration with the GTRI QIS Group and supported by grants from the U.S. ARO with funding from the DARPA OLE program, IARPA, and the MURI program; and the NSF Physics Frontier Center at JQI.

  5. Trapped ion simulation of molecular spectrum

    NASA Astrophysics Data System (ADS)

    Shen, Yangchao; Lu, Yao; Zhang, Kuan; Zhang, Shuaining; Huh, Joonsuk; Kim, Kihwan

    2016-05-01

    Boson sampling had been suggested as a classically intractable and quantum mechanically manageable problem via computational complexity theory arguments. Recently, Huh and co-workers proposed theoretically a modified version of boson sampling, which is designed to simulate a molecular problem, as a practical application. Here, we report the experimental implementation of the theoretical proposal with a trapped ion system. As a first demonstration, we perform the quantum simulation of molecular vibronic profile of SO2, which incorporates squeezing, rotation and coherent displacements operations, and the collective projection measurement on phonon modes. This work was supported by the National Basic Research Program of China 11CBA00300, 2011CBA00301, National Natural Science Foundation of China 11374178, 11574002. Basic Science Research Program of Korea NRF-2015R1A6A3A04059773.

  6. JPL Ultrastable Trapped Ion Atomic Frequency Standards.

    PubMed

    Burt, Eric A; Yi, Lin; Tucker, Blake; Hamell, Robert; Tjoelker, Robert L

    2016-07-01

    Recently, room temperature trapped ion atomic clock development at the Jet Propulsion Laboratory (JPL) has focused on three directions: 1) ultrastable atomic clocks, usually for terrestrial applications emphasizing ultimate stability performance and autonomous timekeeping; 2) new atomic clock technology for space flight applications that require strict adherence to size, weight, and power requirements; and 3) miniature clocks. In this paper, we concentrate on the first direction and present a design and the initial results from a new ultrastable clock referred to as L10 that achieves a short-term stability of 4.5 ×10(-14)/τ(1/2) and an initial measurement of no significant drift with an uncertainty of 2.4 ×10(-16) /day over a two-week period. PMID:27249827

  7. Experimental Uhrig dynamical decoupling using trapped ions

    NASA Astrophysics Data System (ADS)

    Biercuk, Michael J.; Uys, Hermann; Vandevender, Aaron P.; Shiga, Nobuyasu; Itano, Wayne M.; Bollinger, John J.

    2009-06-01

    We present a detailed experimental study of the Uhrig dynamical decoupling (UDD) sequence in a variety of noise environments. Our qubit system consists of a crystalline array of B9e+ ions confined in a Penning trap. We use an electron-spin-flip transition as our qubit manifold and drive qubit rotations using a 124 GHz microwave system. We study the effect of the UDD sequence in mitigating phase errors and compare against the well known Carr-Purcell-Meiboom-Gill-style multipulse spin echo as a function of pulse number, rotation axis, noise spectrum, and noise strength. Our results agree well with theoretical predictions for qubit decoherence in the presence of classical phase noise, accounting for the effect of finite-duration π pulses. Finally, we demonstrate that the Uhrig sequence is more robust against systematic over- or under-rotation and detuning errors than is multipulse spin echo, despite the precise prescription for pulse timing in UDD.

  8. An ion trap built with photonic crystal fibre technology

    SciTech Connect

    Lindenfelser, F. Keitch, B.; Kienzler, D.; Home, J. P.; Bykov, D.; Uebel, P.; Russell, P. St. J.

    2015-03-15

    We demonstrate a surface-electrode ion trap fabricated using techniques transferred from the manufacture of photonic-crystal fibres. This provides a relatively straightforward route for realizing traps with an electrode structure on the 100 micron scale with high optical access. We demonstrate the basic functionality of the trap by cooling a single ion to the quantum ground state, allowing us to measure a heating rate from the ground state of 787 ± 24 quanta/s. Variation of the fabrication procedure used here may provide access to traps in this geometry with trap scales between 100 μm and 10 μm.

  9. Progress Report on the Improved Linear Ion Trap Physics Package

    NASA Technical Reports Server (NTRS)

    Prestage, John D.

    1995-01-01

    This article describes the first operational results from the extended linear ion trap frequency standard now being developed at JPL. This new design separates the state selection/interrogation region from the more critical microwave resonance region where the multiplied local oscillator (LO) signal is compared to the stable atomic transition. Hg+ ions have been trapped, shuttled back and forth between the resonance and state selection traps. In addition, microwave transitions between the Hg+ clock levels have been driven in the resonance trap and detected in the state selection trap.

  10. An ion trap built with photonic crystal fibre technology.

    PubMed

    Lindenfelser, F; Keitch, B; Kienzler, D; Bykov, D; Uebel, P; Schmidt, M A; Russell, P St J; Home, J P

    2015-03-01

    We demonstrate a surface-electrode ion trap fabricated using techniques transferred from the manufacture of photonic-crystal fibres. This provides a relatively straightforward route for realizing traps with an electrode structure on the 100 micron scale with high optical access. We demonstrate the basic functionality of the trap by cooling a single ion to the quantum ground state, allowing us to measure a heating rate from the ground state of 787 ± 24 quanta/s. Variation of the fabrication procedure used here may provide access to traps in this geometry with trap scales between 100 μm and 10 μm. PMID:25832211

  11. Four-Sector Cylindrical Radio-Frequency Ion Trap

    NASA Technical Reports Server (NTRS)

    Melbourne, Ruthann K.; Prestage, John D.; Maleki, Lutfollah

    1992-01-01

    Proposed linear radio-frequency ion trap consists of closed metal cylinder partitioned into four equal cylindrical-sector electrodes and two circular end electrodes. Features include relatively large ion-storage capacity and shielding against external fields. Used in frequency-standard laboratories to confine 199Hg+ ions electrodynamically in isolation from external environment. Similar to device described in "Linear Ion Trap for Atomic Clock" (NPO-17758).

  12. How far can ion trap miniaturization go? Parameter scaling and space-charge limits for very small cylindrical ion traps.

    PubMed

    Tian, Yuan; Higgs, Jessica; Li, Ailin; Barney, Brandon; Austin, Daniel E

    2014-03-01

    A broad effort is underway to make radiofrequency (RF) ion trap mass spectrometers small enough for portable chemical analysis. A variety of trap geometries and fabrication approaches are under development from several research groups. A common issue is the reduced trapping capacity in smaller traps, with the associated reduction in sensitivity. This article explores the key variables that scale with trap size including RF voltage, frequency, electrical capacitance, power and pseudopotential well depth. High-field electric breakdown constrains the maximum RF voltages used in smaller ion traps. Simulations show the effects of space charge and the limits of trapping capacity as a function of trap dimensions for cylindrical ion traps down to the micrometer level. RF amplitudes that scale as the 1/3, 1/2 and 2/3 power of trap radius, r0, were studied. At a fixed level of performance, the number of analyzable ions scales as r0(n), with n ranging from 1.55 to 1.75 depending on the choice of voltage scaling. The implications for miniaturized ion trap mass spectrometry are discussed. PMID:24619549

  13. Proton Transfer Reaction Ion Trap Mass Spectrometer

    SciTech Connect

    Prazeller, Peter; Palmer, Peter T.; Boscaini, Elena; Jobson, B Tom T.; Alexander, M. Lizabeth

    2003-06-11

    Proton transfer reaction mass spectrometry is a relatively new field that has attracted a great deal of interest in the last few years. This technique uses H₃Oþ as a chemical ionization (CI) reagent to measure volatile organic compounds (VOCs) in the parts per billion by volume (ppbv) to parts per trillion by volume (pptv) range. Mass spectra acquired with a proton transfer reaction mass spectrometer (PTR-MS) are simple because proton transfer chemical ionization is ‘soft’ and results in little or no fragmentation. Unfortunately, peak identification can still be difficult due to isobaric interferences. A possible solution to this problem is to couple the PTR drift tube to an ion trap mass spectrometer (ITMS). The use of an ITMS is appealing because of its ability to perform MS/MS and possibly distinguish between isomers and other isobars. Additionally, the ITMS duty cycle is much higher than that of a linear quadrupole so faster data acquisition rates are possible that will allow for detection of multiple compounds. Here we present the first results from a proton transfer reaction ion trap mass spectrometer (PTR-ITMS). The aim of this study was to investigate ion injection and storage efficiency of a simple prototype instrument in order to estimate possible detection limits of a second-generation instrument. Using this prototype a detection limit of 100 ppbv was demonstrated. Modifications are suggested that will enable further reduction in detection limits to the low-ppbv to high-pptv range. Furthermore, the applicability of MS/MS in differentiating between isobaric species was determined. MS/MS spectra of the isobaric compounds methyl vinyl ketone (MVK) and methacrolein (MACR) are presented and show fragments of different mass making differentiation possible, even when a mixture of both species is present in the same sample. However, MS/MS spectra of acetone and propanal produce fragments with the same molecular masses but with different intensity ratios

  14. Proton Transfer Reaction Ion Trap Mass Spectrometer

    SciTech Connect

    Prazeller, Peter; Palmer, Peter T.; Boscaini, Elena; Jobson, B Tom; Alexander, M. Lizabeth

    2003-07-07

    Proton Transfer Reaction Mass Spectrometry (PTR-MS) is a relatively new field that has attracted a great deal of interest in the last several years. This technique uses H3O+ as a chemical ionization (CI) agent for measuring volatile organic compounds (VOCs) in the parts per billion by volume (ppbv) - parts per trillion by volume (pptv) range. PTR-MS mass spectra are simple because the ionization method of proton transfer is “soft”, resulting in little or no fragmentation. Unfortunately, the simplicity of the mass spectra can cause problems in peak identification due to isobaric interferences. A possible solution to this problem is to couple the PTR drift tube to an ion trap mass spectrometer (ITMS). ITMS is appealing because of the ability to perform MS/MS and possibly distinguish between isomers and other isobars. Additionally, the ITMS duty cycle is much higher than that of a linear quadrupole so faster data acquisition rates can be realized for detection of multiple compounds. We present here the first results from a Proton Transfer Reaction Ion Trap Mass Spectrometer (PTR-ITMS). The aim of this study was to investigate ion injection and storage efficiency of a simple prototype interface in order to estimate possible detection limits of a second generation instrument. Using this prototype a detection limit of 100 ppbv was demonstrated for the PTR-ITMS. Modifications are suggested that will enable further reduction in detection limits to the low ppbv to pptv range. Furthermore the applicability of MS/MS to differentiate between isobaric species was determined. MS/MS spectra of the isobaric compounds methyl vinyl ketone (MVK) and methacrolein (MACR) are presented and show fragments of different mass making a differentiation possible even when a mixture of both species is present in the same sample. MS/MS spectra of acetone and propanal produce fragments with the same molecular weight but different ratios, allowing quantitative distinction only if one species

  15. Efficient photoionization loading of trapped ions with ultrafast pulses

    SciTech Connect

    Deslauriers, L.; Acton, M.; Blinov, B. B.; Brickman, K.-A.; Haljan, P. C.; Hensinger, W. K.; Hucul, D.; Katnik, S.; Kohn, R. N. Jr.; Lee, P. J.; Madsen, M. J.; Maunz, P.; Olmschenk, S.; Moehring, D. L.; Stick, D.; Sterk, J.; Yeo, M.; Younge, K. C.; Monroe, C.

    2006-12-15

    Atomic cadmium ions are loaded into radiofrequency ion traps by photoionization of atoms in a cadmium vapor with ultrafast laser pulses. The photoionization is driven through an intermediate atomic resonance with a frequency-quadrupled mode-locked Ti:sapphire laser that produces pulses of either 100-fs or 1-ps duration at a central wavelength of 229 nm. The large bandwidth of the pulses photoionizes all velocity classes of the Cd vapor, resulting in a high loading efficiency compared to previous ion trap loading techniques. Measured loading rates are compared with a simple theoretical model, and we conclude that this technique can potentially ionize every atom traversing the laser beam within the trapping volume. This may allow the operation of ion traps with lower levels of background pressures and less trap electrode surface contamination. The technique and laser system reported here should be applicable to loading most laser-cooled ion species.

  16. Efficient photoionization loading of trapped ions with ultrafast pulses

    NASA Astrophysics Data System (ADS)

    Deslauriers, L.; Acton, M.; Blinov, B. B.; Brickman, K.-A.; Haljan, P. C.; Hensinger, W. K.; Hucul, D.; Katnik, S.; Kohn, R. N., Jr.; Lee, P. J.; Madsen, M. J.; Maunz, P.; Olmschenk, S.; Moehring, D. L.; Stick, D.; Sterk, J.; Yeo, M.; Younge, K. C.; Monroe, C.

    2006-12-01

    Atomic cadmium ions are loaded into radiofrequency ion traps by photoionization of atoms in a cadmium vapor with ultrafast laser pulses. The photoionization is driven through an intermediate atomic resonance with a frequency-quadrupled mode-locked Ti:sapphire laser that produces pulses of either 100-fs or 1-ps duration at a central wavelength of 229nm . The large bandwidth of the pulses photoionizes all velocity classes of the Cd vapor, resulting in a high loading efficiency compared to previous ion trap loading techniques. Measured loading rates are compared with a simple theoretical model, and we conclude that this technique can potentially ionize every atom traversing the laser beam within the trapping volume. This may allow the operation of ion traps with lower levels of background pressures and less trap electrode surface contamination. The technique and laser system reported here should be applicable to loading most laser-cooled ion species.

  17. Blue-sky bifurcation of ion energies and the limits of neutral-gas sympathetic cooling of trapped ions

    PubMed Central

    Schowalter, Steven J.; Dunning, Alexander J.; Chen, Kuang; Puri, Prateek; Schneider, Christian; Hudson, Eric R.

    2016-01-01

    Sympathetic cooling of trapped ions through collisions with neutral buffer gases is critical to a variety of modern scientific fields, including fundamental chemistry, mass spectrometry, nuclear and particle physics, and atomic and molecular physics. Despite its widespread use over four decades, there remain open questions regarding its fundamental limitations. To probe these limits, here we examine the steady-state evolution of up to 10 barium ions immersed in a gas of three-million laser-cooled calcium atoms. We observe and explain the emergence of nonequilibrium behaviour as evidenced by bifurcations in the ion steady-state temperature, parameterized by ion number. We show that this behaviour leads to the limitations in creating and maintaining translationally cold samples of trapped ions using neutral-gas sympathetic cooling. These results may provide a route to studying non-equilibrium thermodynamics at the atomic level. PMID:27511602

  18. Blue-sky bifurcation of ion energies and the limits of neutral-gas sympathetic cooling of trapped ions.

    PubMed

    Schowalter, Steven J; Dunning, Alexander J; Chen, Kuang; Puri, Prateek; Schneider, Christian; Hudson, Eric R

    2016-01-01

    Sympathetic cooling of trapped ions through collisions with neutral buffer gases is critical to a variety of modern scientific fields, including fundamental chemistry, mass spectrometry, nuclear and particle physics, and atomic and molecular physics. Despite its widespread use over four decades, there remain open questions regarding its fundamental limitations. To probe these limits, here we examine the steady-state evolution of up to 10 barium ions immersed in a gas of three-million laser-cooled calcium atoms. We observe and explain the emergence of nonequilibrium behaviour as evidenced by bifurcations in the ion steady-state temperature, parameterized by ion number. We show that this behaviour leads to the limitations in creating and maintaining translationally cold samples of trapped ions using neutral-gas sympathetic cooling. These results may provide a route to studying non-equilibrium thermodynamics at the atomic level. PMID:27511602

  19. METHOD AND APPARATUS FOR TRAPPING IONS IN A MAGNETIC FIELD

    DOEpatents

    Luce, J.S.

    1962-04-17

    A method and apparatus are described for trapping ions within an evacuated container and within a magnetic field utilizing dissociation and/or ionization of molecular ions to form atomic ions and energetic neutral particles. The atomic ions are magnetically trapped as a result of a change of charge-to- mass ratio. The molecular ions are injected into the container and into the path of an energetic carbon arc discharge which dissociates and/or ionizes a portion of the molecular ions into atomic ions and energetic neutrals. The resulting atomic ions are trapped by the magnetic field to form a circulating beam of atomic ions, and the energetic neutrals pass out of the system and may be utilized in a particle accelerator. (AEC)

  20. Space-charge effects in Penning ion traps

    NASA Astrophysics Data System (ADS)

    Porobić, T.; Beck, M.; Breitenfeldt, M.; Couratin, C.; Finlay, P.; Knecht, A.; Fabian, X.; Friedag, P.; Fléchard, X.; Liénard, E.; Ban, G.; Zákoucký, D.; Soti, G.; Van Gorp, S.; Weinheimer, Ch.; Wursten, E.; Severijns, N.

    2015-06-01

    The influence of space-charge on ion cyclotron resonances and magnetron eigenfrequency in a gas-filled Penning ion trap has been investigated. Off-line measurements with K39+ using the cooling trap of the WITCH retardation spectrometer-based setup at ISOLDE/CERN were performed. Experimental ion cyclotron resonances were compared with ab initio Coulomb simulations and found to be in agreement. As an important systematic effect of the WITCH experiment, the magnetron eigenfrequency of the ion cloud was studied under increasing space-charge conditions. Finally, the helium buffer gas pressure in the Penning trap was determined by comparing experimental cooling rates with simulations.

  1. Ion-beam cleaning for cold welds

    NASA Technical Reports Server (NTRS)

    Slater, B. L.

    1980-01-01

    1000 eV beam bombarding metal surfaces to be joined removes oxides and contaminants at rate of several atomic layers per second for current density of 1 mA/squ. cm. Clean surfaces can then be joined by squeezing them together. With ion-beam cleaning, mating force for strong bond is low enough to cause only 1% deformation. Conventional cold-welding requires about 70% deformation for bonding. Technique was tested successfully on aluminum to aluminum welds, copper to copper, copper to aluminum, copper to nickel, and silver to iron. Base metals failed before welds in tear test.

  2. Cold Ion Escape from the Martian Ionosphere

    NASA Astrophysics Data System (ADS)

    Fränz, M.; Dubinin, E.; Andrews, D.; Nilsson, H.; Barabash, S.; Fedorov, A.

    2015-10-01

    We here report on new measurements of the escape flux of oxygen ions from Mars by combining the observations of the ASPERA-3 and MARSIS experiments on board the European Mars Express spacecraft. We show that in previous estimates of the total heavy ion escape flow the contribution of the coldionospheric outflow with energies below 10 eV has been underestimated. Both case studies and the derived flow pattern indicate that the cold plasma observed by MARSIS and the superthermal plasma observed by ASPERA-3 move with the same bulk speed in most regions of the Martian tail. We determine maps of the tailside heavy ion flux distribution derived from mean ion velocity distributions sampled over 7 years. If we assume that the superthermal bulk speed derived from these long time averages of the ion distribution function represent the total plasma bulk speed we derive the total tailside plasma flux. Assuming cylindrical symmetry we determine the mean total escape rate for the years 2007 to 2014 at 2.9±0.2×10 25 atoms/s which is in good agreement with model estimates. In this talk we will also try to compare these results with more recent observations by the MAVEN spacecraft. Possible mechanism to generate this flux can be the ionospheric pressure gradient between dayside and nightside or momentum transfer from the solar wind via the induced magnetic field since the flow velocity is in the Alfvénic regime.

  3. Electron source for a mini ion trap mass spectrometer

    DOEpatents

    Dietrich, Daniel D.; Keville, Robert F.

    1995-01-01

    An ion trap which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10.sup.9 and commercial mass spectrometers requiring 10.sup.4 ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products.

  4. Electron source for a mini ion trap mass spectrometer

    DOEpatents

    Dietrich, D.D.; Keville, R.F.

    1995-12-19

    An ion trap is described which operates in the regime between research ion traps which can detect ions with a mass resolution of better than 1:10{sup 9} and commercial mass spectrometers requiring 10{sup 4} ions with resolutions of a few hundred. The power consumption is kept to a minimum by the use of permanent magnets and a novel electron gun design. By Fourier analyzing the ion cyclotron resonance signals induced in the trap electrodes, a complete mass spectra in a single combined structure can be detected. An attribute of the ion trap mass spectrometer is that overall system size is drastically reduced due to combining a unique electron source and mass analyzer/detector in a single device. This enables portable low power mass spectrometers for the detection of environmental pollutants or illicit substances, as well as sensors for on board diagnostics to monitor engine performance or for active feedback in any process involving exhausting waste products. 10 figs.

  5. Compact toroidal ion-trap design and optimization

    SciTech Connect

    Madsen, M. J.; Gorman, C. H.

    2010-10-15

    We present the design of a type of compact toroidal, or 'halo', ion trap. Such traps may be useful for mass spectrometry, studying small Coulomb cluster rings, quantum-information applications, or other quantum simulations where a ring topology is of interest. We present results from a Monte Carlo optimization of the trap design parameters using finite-element analysis simulations that minimize higher-order anharmonic terms in the trapping pseudopotential, while maintaining complete control over ion placement at the pseudopotential node in three dimensions using static bias fields. These simulations are based on a practical electrode design using readily available parts, yet can be easily scaled to any size trap with similar electrode spacings. We also derive the conditions for a crystal structure transition for two ions in the compact halo trap, the first nontrivial transition for Coulomb crystals in this geometry.

  6. A Scalable Microfabricated Ion Trap for Quantum Information Processing

    NASA Astrophysics Data System (ADS)

    Maunz, Peter; Haltli, Raymond; Hollowell, Andrew; Lobser, Daniel; Mizrahi, Jonathan; Rembetski, John; Resnick, Paul; Sterk, Jonathan D.; Stick, Daniel L.; Blain, Matthew G.

    2016-05-01

    Trapped Ion Quantum Information Processing (QIP) relies on complex microfabricated trap structures to enable scaling of the number of quantum bits. Building on previous demonstrations of surface-electrode ion traps, we have designed and characterized the Sandia high-optical-access (HOA-2) microfabricated ion trap. This trap features high optical access, high trap frequencies, low heating rates, and negligible charging of dielectric trap components. We have observed trap lifetimes of more than 100h, measured trap heating rates for ytterbium of less than 40quanta/s, and demonstrated shuttling of ions from a slotted to an above surface region and through a Y-junction. Furthermore, we summarize demonstrations of high-fidelity single and two-qubit gates realized in this trap. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under Contract DE-AC04-94AL85000. This work was supported by the Intelligence Advanced Research Projects Activity (IARPA).

  7. Ion collision crosssection measurements in quadrupole ion traps using a time-frequency analysis method.

    PubMed

    He, Muyi; Guo, Dan; Chen, Yu; Xiong, Xingchuang; Fang, Xiang; Xu, Wei

    2014-12-01

    In this study, a method for measuring ion collision crosssections (CCSs) was proposed through time-frequency analysis of ion trajectories in quadrupole ion traps. A linear ion trap with added high-order electric fields was designed and simulated. With the presence of high-order electric fields and ion-neutral collisions, ion secular motion frequency within the quadrupole ion trap will be a function of ion motion amplitude, thus a function of time and ion CCS. A direct relationship was then established between ion CCS and ion motion frequency with respect to time, which could be obtained through time-frequency analysis of ion trajectories (or ion motion induced image currents). To confirm the proposed theory, realistic ion trajectory simulations were performed, where the CCSs of bradykinin, angiotensin I and II, and ubiquitin ions were calculated from simulated ion trajectories. As an example, differentiation of isomeric ubiquitin ions was also demonstrated in the simulations. PMID:25319271

  8. Design and operation of the electron beam ion trap

    SciTech Connect

    Vogel, D.

    1990-05-30

    This report describes the basic features and operating principles of the Electron Beam Ion Trap. The differences between EBIT and other sources of highly charged ions are outlined. Its features and operating parameters are discussed. The report also explains why certain design choices were necessary and the constraints involved in building an electron beam ion trap. EBIT's evaporation cooling system is described in detail. 13 refs., 8 figs.

  9. Toward scalable ion traps for quantum information processing

    NASA Astrophysics Data System (ADS)

    Amini, J. M.; Uys, H.; Wesenberg, J. H.; Seidelin, S.; Britton, J.; Bollinger, J. J.; Leibfried, D.; Ospelkaus, C.; VanDevender, A. P.; Wineland, D. J.

    2010-03-01

    In this paper, we report the design, fabrication and preliminary testing of a 150 zone ion trap array built in a 'surface-electrode' geometry microfabricated on a single substrate. We demonstrate the transport of atomic ions between the legs of a 'Y'-type junction and measure the in-situ heating rates for the ions. The trap design demonstrates the use of a basic component design library that can be quickly assembled to form structures optimized for a particular experiment.

  10. Ion Sponge: A 3-Dimentional Array of Quadrupole Ion Traps for Trapping and Mass-Selectively Processing Ions in Gas Phase

    PubMed Central

    2015-01-01

    In this study, the concept of ion sponge has been explored for developing 3D arrays of large numbers of ion traps but with simple configurations. An ion sponge device with 484 trapping units in a volume of 10 × 10 × 3.2 cm has been constructed by simply stacking 9 meshes together. A single rf was used for trapping ions and mass-selective ion processing. The ion sponge provides a large trapping capacity and is highly transparent for transfer of ions, neutrals, and photons for gas phase ion processing. Multiple layers of quadrupole ion traps, with 121 trapping units in each layer, can operate as a single device for MS or MS/MS analysis, or as a series of mass-selective trapping devices with interlayer ion transfers facilitated by AC and DC voltages. Automatic sorting of ions to different trapping layers based on their mass-to-charge (m/z) ratios was achieved with traps of different sizes. Tandem-in-space MS/MS has also been demonstrated with precursor ions and fragment ions trapped in separate locations. PMID:24758328

  11. Cold ion heating at the dayside magnetopause during magnetic reconnection

    NASA Astrophysics Data System (ADS)

    Toledo-Redondo, S.; André, M.; Vaivads, A.; Khotyaintsev, Yu. V.; Lavraud, B.; Graham, D. B.; Divin, A.; Aunai, N.

    2016-01-01

    Cold ions of ionospheric origin are known to be present in the magnetospheric side of the Earth's magnetopause. They can be very abundant, with densities up to 100 cm-3. These cold ions can mass load the magnetosphere, changing global parameters of magnetic reconnection, like the Alfvén speed or the reconnection rate. In addition they introduce a new length scale related to their gyroradius and kinetic effects which must be accounted for. We report in situ observations of cold ion heating in the separatrix owing to time and space fluctuations of the electric field. When this occurs, the cold ions are preheated before crossing the Hall electric field barrier. However, when this mechanism is not present cold ions can be observed well inside the reconnection exhaust. Our observations suggest that the perpendicular cold ion heating is stronger close to the X line owing to waves and electric field gradients linked to the reconnection process.

  12. Single Motional Quantum Exchange between Independently Trapped Ions

    NASA Astrophysics Data System (ADS)

    Brown, K. R.; Ospelkaus, C.; Colombe, Y.; Wilson, A. C.; Leibfried, D.; Wineland, D. J.

    2011-05-01

    The Coulomb coupling of ions in separate potential wells is a key feature of proposals to implement quantum simulation and could enable logic operations to be performed in a multi-zone quantum information processor without the requirement of bringing the ion qubits into the same trapping potential. It might also extend the capabilities of quantum logic spectroscopy to ions that cannot be trapped in the same potential well as the measurement ion, such as oppositely charged ions or even antimatter particles. We report recent results demonstrating tunable coupling of two 9Be+ ions held in trapping potentials separated by 40 μm. The ions are trapped 40 μm above the surface of a microfabricated planar trap with independently tunable axial frequencies of ~4 MHz. The trap is cooled to 4.2 K with a helium bath cryostat to suppress anomalous heating and to extend the lifetime of ions from minutes to days. By preparing approximate motional number states with n=0 and n=1 in the respective wells, and tuning the confining wells into resonance, a single quantum of motion is exchanged between the ions in ~200 μs. Work supported by IARPA, DARPA, ONR, and the NIST Quantum Information Program.

  13. A system for trapping barium ions in a microfabricated surface trap

    SciTech Connect

    Graham, R. D. Sakrejda, T.; Wright, J.; Zhou, Z.; Blinov, B. B.; Chen, S.-P.

    2014-05-15

    We have developed a vacuum chamber and control system for rapid testing of microfabricated surface ion traps. Our system is modular in design and is based on an in-vacuum printed circuit board with integrated filters. We have used this system to successfully trap and cool barium ions and have achieved ion ‘dark' lifetimes of 31.6 s ± 3.4 s with controlled shuttling of ions. We provide a detailed description of the ion trap system including the in-vacuum materials used, control electronics and neutral atom source. We discuss the challenges presented in achieving a system which can work reliably over two years of operations in which the trap under test was changed at least 10 times.

  14. Charged-Particle Bean Transport for Ion Trapping Experiments.

    NASA Astrophysics Data System (ADS)

    Raichle, Brian W.; Wingfield, Love M.

    2001-11-01

    Electrostatic Einsel lenses are being developed for beam transport for use in two distinct metastable atomic lifetime experiments using two separate rf-ion traps. Each system has been modeled using Simion software, and the lenses have been designed from commercially available eV-parts. The first application is part of an electron gun source. Electrons are produced by a conventional dispenser cathode and are transported 25 cm to the trap. The design goal is to create a beam divergence to fully illuminate the active trap volume, and to provide tunable electron energies from 50 to 500 eV. The second application is to transport ions 1 m from a laser ablation ion source to an rf ion trap. Laser ablation involves essentially boiling ions from a solid target with intense laser pulses. Here, the design goal is to maximize flux by maximizing the solid angle of acceptance to the trap, minimize radial velocity, and minimize the spread in axial velocity. Development of a laser ablation ion source external to the trap volume will allow a very low base pressure in the trap region, which will make possible the study of species with lifetimes approaching 1 s. In addition, laser ablation will produce intermediately-charged ions from non-conductive solid targets.

  15. Rydberg excitation of trapped strontium ions (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Hennrich, Markus; Higgins, Gerard; Pokorny, Fabian; Kress, Florian; Maier, Christine; Haag, Johannes; Colombe, Yves

    2016-04-01

    Trapped Rydberg ions are a novel approach for quantum information processing [1,2]. This idea joins the advanced quantum control of trapped ions with the strong dipolar interaction between Rydberg atoms. For trapped ions this method promises to speed up entangling interactions [3] and to enable such operations in larger ion crystals [4]. We report on the first experimental realization of trapped strontium Rydberg ions. A single ion was confined in a linear Paul trap and excited to Rydberg states (25S to 37S) using a two-photon excitation with 243nm and 308nm laser light. The transitions we observed are narrow and the excitation can be performed repeatedly which indicates that the Rydberg ions are stable in the ion trap. Similar results have been recently reported on a single photon Rydberg excitation of trapped calcium ions [5]. The tunability of the 304-309nm laser should enable us to excite our strontium ions to even higher Rydberg levels. Such highly excited levels are required to achieve a strong interaction between neighboring Rydberg ions in the trap as will be required for quantum gates using the Rydberg interaction. References [1] M. Müller, L. Liang, I. Lesanovsky, P. Zoller, New J. Phys. 10, 093009 (2008). [2] F. Schmidt-Kaler, et al., New J. Phys. 13, 075014 (2011). [3] W. Li, I. Lesanovsky, Appl. Phys. B 114, 37-44 (2014). [4] W. Li, A.W. Glaetzle, R. Nath, I. Lesanovsky, Phys. Rev. A 87, 052304 (2013). [5] T. Feldker, et al., arXiv:1506.05958

  16. Ion trap array mass analyzer: structure and performance.

    PubMed

    Li, Xiaoxu; Jiang, Gongyu; Luo, Chan; Xu, Fuxing; Wang, Yuanyuan; Ding, Li; Ding, Chuan-Fan

    2009-06-15

    An ion trap array (ITA) mass analyzer--a novel ion trap mass analyzer with multiple ion trapping and analyzing channels--was designed and constructed. Its property and performance were investigated and reported in this paper. The ITA was built with several planar electrodes including two parallel printed circuit board (PCB) plates. Each PCB plate was fabricated to several identical rectangular electric strips based on normal PCB fabrication technology and was placed symmetrically to those on the opposite plate. There is no electrode between any two adjacent strips. Every strip was supplied with an rf voltage while the polarity of the voltage applied to the adjacent two strips was opposite. So the electric potential at the central plane between two adjacent strips is zero. Multiple identical electric field regions that contain the dominant quadrupole plus some other high-order fields were produced between the two PCB plates. The multiple identical electric field regions will have the property of ion trapping, ion storage, and mass analysis functions. So an ITA could work as multiple ion trap mass analyzers. It could perform multiple sample ion storage, mass-selected ion isolation, ion ejection, and mass analysis simultaneously. The ITA was operated at both "digital ion trap mode" and "conventional rf mode" experimentally. A preliminary mass spectrum has been carried out in one of the ion trap channels, and it shows a mass resolution of over 1000. Additional functions such as mass-selected ion isolation and mass-selected ion ejection have also been tested. Furthermore, the ITA has a small size and very low cost. An ITA with four channels is less than 30 cm(3) in total volume, and it shows a great promise for the miniaturization of the whole mass spectrometer instrument and high-throughput mass analysis. PMID:19441854

  17. Optimal surface-electrode trap lattices for quantum simulation with trapped ions.

    PubMed

    Schmied, Roman; Wesenberg, Janus H; Leibfried, Dietrich

    2009-06-12

    Trapped ions offer long internal state (spin) coherence times and strong interparticle interactions mediated by the Coulomb force. This makes them interesting candidates for quantum simulation of coupled lattices. To this end, it is desirable to be able to trap ions in arbitrary conformations with precisely controlled local potentials. We provide a general method for optimizing periodic planar radio-frequency electrodes for generating ion trapping potentials with specified trap locations and curvatures above the electrode plane. A linear-programming algorithm guarantees globally optimal electrode shapes that require only a single radio-frequency voltage source for operation. The optimization method produces final electrode shapes that are smooth and exhibit low fragmentation. Such characteristics are desirable for practical fabrication of surface-electrode trap lattices. PMID:19658931

  18. Development of a low-temperature photoelectron spectroscopy instrument using an electrospray ion source and a cryogenically controlled ion trap

    SciTech Connect

    Wang Xuebin; Wang Laisheng

    2008-07-15

    The ability to control ion temperatures is critical for gas phase spectroscopy and has been a challenge in chemical physics. A low-temperature photoelectron spectroscopy instrument has been developed for the investigation of complex anions in the gas phase, including multiply charged anions, solvated species, and biological molecules. The new apparatus consists of an electrospray ionization source, a three dimensional (3D) Paul trap for ion accumulation and cooling, a time-of-flight mass spectrometer, and a magnetic-bottle photoelectron analyzer. A key feature of the new instrument is the capability to cool and tune ion temperatures from 10 to 350 K in the 3D Paul trap, which is attached to the cold head of a closed cycle helium refrigerator. Ion cooling is accomplished in the Paul trap via collisions with a background gas and has been demonstrated by observation of complete elimination of vibrational hot bands in photoelectron spectra of various anions ranging from small molecules to complex species. Further evidence of ion cooling is shown by the observation of H{sub 2}-physisorbed anions at low temperatures. Cold anions result in better resolved photoelectron spectra due to the elimination of vibrational hot bands and yield more accurate energetic and spectroscopic information. Temperature-dependent studies are made possible for weakly bonded molecular and solvated clusters, allowing thermodynamic information to be obtained.

  19. Development of a Low-Temperature Photoelectron Spectroscopy Instrument Using an Electrospray Ion Source and a Cryogenically Controlled Ion Trap

    SciTech Connect

    Wang, Xue B.; Wang, Lai S.

    2008-07-01

    The ability to control ion temperatures is critical for gas phase spectroscopy and has been a challenge in chemical physics. A low-temperature photoelectron spectroscopy instrument has been developed for the investigation of complex anions in the gas phase, including multiply charged anions, solvated species, and biological molecules. The new apparatus consists of an electrospray ionization source, a 3D Paul trap for ion accumulation and cooling, a time-of-flight mass spectrometer, and a magnetic-bottle photoelectron analyzer. A key feature of the new instrument is the capability to cool and tune ion temperatures from 10 to 350 K in the 3D Paul trap, which is attached to the cold head of a closed-cycle helium refrigerator. Ion cooling is accomplished in the Paul trap via collisions with a background gas and has been demonstrated by observation of complete elimination of vibrational hot bands in photoelectron spectra of various anions ranging from small molecules to complex species. Further evidence of ion cooling is shown by the observation of H2 physisorbed anions at low temperatures. Cold anions result in better resolved photoelectron spectra due to the elimination of vibrational hot bands and yield more accurate energetic and spectroscopic information. Temperature-dependent studies are made possible for weakly-bonded molecular and solvated clusters, allowing thermodynamic information to be obtained.

  20. Development of a low-temperature photoelectron spectroscopy instrument using an electrospray ion source and a cryogenically controlled ion trap.

    PubMed

    Wang, Xue-Bin; Wang, Lai-Sheng

    2008-07-01

    The ability to control ion temperatures is critical for gas phase spectroscopy and has been a challenge in chemical physics. A low-temperature photoelectron spectroscopy instrument has been developed for the investigation of complex anions in the gas phase, including multiply charged anions, solvated species, and biological molecules. The new apparatus consists of an electrospray ionization source, a three dimensional (3D) Paul trap for ion accumulation and cooling, a time-of-flight mass spectrometer, and a magnetic-bottle photoelectron analyzer. A key feature of the new instrument is the capability to cool and tune ion temperatures from 10 to 350 K in the 3D Paul trap, which is attached to the cold head of a closed cycle helium refrigerator. Ion cooling is accomplished in the Paul trap via collisions with a background gas and has been demonstrated by observation of complete elimination of vibrational hot bands in photoelectron spectra of various anions ranging from small molecules to complex species. Further evidence of ion cooling is shown by the observation of H2-physisorbed anions at low temperatures. Cold anions result in better resolved photoelectron spectra due to the elimination of vibrational hot bands and yield more accurate energetic and spectroscopic information. Temperature-dependent studies are made possible for weakly bonded molecular and solvated clusters, allowing thermodynamic information to be obtained. PMID:18681692

  1. Simplified motional heating rate measurements of trapped ions

    SciTech Connect

    Epstein, R. J.; Seidelin, S.; Leibfried, D.; Wesenberg, J. H.; Bollinger, J. J.; Amini, J. M.; Blakestad, R. B.; Britton, J.; Home, J. P.; Itano, W. M.; Jost, J. D.; Knill, E.; Langer, C.; Ozeri, R.; Shiga, N.; Wineland, D. J.

    2007-09-15

    We have measured motional heating rates of trapped atomic ions, a factor that can influence multi-ion quantum logic gate fidelities. Two simplified techniques were developed for this purpose: one relies on Raman sideband detection implemented with a single laser source, while the second is even simpler and is based on time-resolved fluorescence detection during Doppler recooling. We applied these methods to determine heating rates in a microfrabricated surface-electrode trap made of gold on fused quartz, which traps ions 40 {mu}m above its surface. Heating rates obtained from the two techniques were found to be in reasonable agreement. In addition, the trap gives rise to a heating rate of 300{+-}30 s{sup -1} for a motional frequency of 5.25 MHz, substantially below the trend observed in other traps.

  2. Multilayer Interconnects for Microfabricated Surface Electrode Ion Traps

    NASA Astrophysics Data System (ADS)

    Amini, Jason; Seidelin, Signe; Wesenberg, Janus; Britton, Joe; Blakestad, Brad; Brown, Kenton; Epstein, Ryan; Home, Jonathan; Jost, John; Langer, Chris; Leibfried, Dietrich; Ozeri, Roee; Wineland, David

    2007-06-01

    Microfabricated surface electrode traps for ions are a promising technology for building scalable trapping geometries for quantum information processing. We have expanded upon our single layer gold-on-fused-silica surface electrode trap [1] to include a second patterned conducting layer under the trapping electrodes and have demonstrated the fabrication of this architecture using standard microfabrication techniques. The multilayer approach allows for a significant increase in multi-zone trapping complexity and permits improved trapping structures that are otherwise unattainable in single layer designs without vertical interconnects through the wafer. Using improved calculational methods [2], we are in the process of optimizing the planar designs to create modular elements that can be joined into larger multi-zone trapping structures. Work supported by DTO and NIST. 1. S. Seidelin et al., Phys. Rev. Lett. 96, 253003 (2006). Also, see the abstract by S. Seidelin. 2. See the abstract by J. H. Wesenberg.

  3. Method and apparatus for regenerating cold traps within liquid-metal systems

    DOEpatents

    McKee, Jr., John M.

    1976-01-01

    Oxide and hydride impurities of a liquid metal such as sodium are removed from a cold trap by heating to a temperature at which the metal hydroxide is stable in a molten state. The partial pressure of hydrogen within the system is measured to determine if excess hydride or oxide is present. Excess hydride is removed by venting hydrogen gas while excess oxide can be converted to molten hydroxide through the addition of hydrogen. The resulting, molten hydroxide is drained from the trap which is then returned to service at cold trap temperatures within the liquid-metal system.

  4. Trapped Ion Quantum Gate Design in Presence of Micromotion

    NASA Astrophysics Data System (ADS)

    Shen, Chao; Duan, Luming

    2014-05-01

    Linearly trapped atomic ions in a linear Paul trap has been the leading architecture of a scalable ion-based quantum computer. Although planar crystals can also be held in a Paul trap, the presense of non-negligible ion micromotion away from the trap axis makes quantum manipulations difficult. Here we propose for the first time a general framework for the design of high fidelity quantum gates with micromotion taken into account. This opens new possibilities for scalable quantum information processing with ion crystals of a general geometry. This work was supported by the NBRPC (973 Program) 2011CBA00300 (2011CBA00302), the IARPA MUSIQC program, the ARO and the AFOSR MURI programs, and the DARPA OLE program.

  5. Scaling and Suppression of Heating in an Adjustable Ion Trap

    NASA Astrophysics Data System (ADS)

    Olmschenk, Steven; Deslauriers, Louis; Stick, Dan; Hensinger, Winfried; Sterk, Jon; Monroe, Christopher

    2006-05-01

    One of the major hurdles in the realization of large entangled states among trapped ions is anomalous heating of trapped ion motion [1]. We implement a novel rf ion trap featuring moveable electrodes that has enabled a controlled investigation of this motional decoherence. First, we characterize heating as a function of electrode proximity, related to the geometry of noisy potentials on the electrode surface. Second, we cool the electrodes via contact with a liquid nitrogen reservoir and observe that the decoherence rate is suppressed by an order of magnitude. The insight gained through these experiments may have relevance to scaling the ion trap quantum information processor. 1. Q. A. Turchette, et. al., Phys. Rev. A 61, 063418 (2000).

  6. Reducing Space Charge Effects in a Linear Ion Trap by Rhombic Ion Excitation and Ejection.

    PubMed

    Zhang, Xiaohua; Wang, Yuzhuo; Hu, Lili; Guo, Dan; Fang, Xiang; Zhou, Mingfei; Xu, Wei

    2016-07-01

    Space charge effects play important roles in ion trap operations, which typically limit the ion trapping capacity, dynamic range, mass accuracy, and resolving power of a quadrupole ion trap. In this study, a rhombic ion excitation and ejection method was proposed to minimize space charge effects in a linear ion trap. Instead of applying a single dipolar AC excitation signal, two dipolar AC excitation signals with the same frequency and amplitude but 90° phase difference were applied in the x- and y-directions of the linear ion trap, respectively. As a result, mass selective excited ions would circle around the ion cloud located at the center of the ion trap, rather than go through the ion cloud. In this work, excited ions were then axially ejected and detected, but this rhombic ion excitation method could also be applied to linear ion traps with ion radial ejection capabilities. Experiments show that space charge induced mass resolution degradation and mass shift could be alleviated with this method. For the experimental conditions in this work, space charge induced mass shift could be decreased by ~50%, and the mass resolving power could be improved by ~2 times at the same time. Graphical Abstract ᅟ. PMID:27080008

  7. Reducing Space Charge Effects in a Linear Ion Trap by Rhombic Ion Excitation and Ejection

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaohua; Wang, Yuzhuo; Hu, Lili; Guo, Dan; Fang, Xiang; Zhou, Mingfei; Xu, Wei

    2016-07-01

    Space charge effects play important roles in ion trap operations, which typically limit the ion trapping capacity, dynamic range, mass accuracy, and resolving power of a quadrupole ion trap. In this study, a rhombic ion excitation and ejection method was proposed to minimize space charge effects in a linear ion trap. Instead of applying a single dipolar AC excitation signal, two dipolar AC excitation signals with the same frequency and amplitude but 90° phase difference were applied in the x- and y-directions of the linear ion trap, respectively. As a result, mass selective excited ions would circle around the ion cloud located at the center of the ion trap, rather than go through the ion cloud. In this work, excited ions were then axially ejected and detected, but this rhombic ion excitation method could also be applied to linear ion traps with ion radial ejection capabilities. Experiments show that space charge induced mass resolution degradation and mass shift could be alleviated with this method. For the experimental conditions in this work, space charge induced mass shift could be decreased by ~50%, and the mass resolving power could be improved by ~2 times at the same time.

  8. Implementation schemes for unsharp measurements with trapped ions

    NASA Astrophysics Data System (ADS)

    Choudhary, Sujit K.; Konrad, T.; Uys, H.

    2013-01-01

    Unsharp positive operator-valued measurements allow a variety of measurement applications which minimally disrupt the state of the quantum system. Experimental schemes are proposed for implementing unsharp measurements on the qubit levels of a trapped ion. The schemes rely on introducing weak entanglement between the state of a target ion and that of an auxiliary ion, using standard ion-trap quantum logic operations, and then realizing an unsharp measurement through projective measurement on the auxiliary atom. We analyze common sources of error and their effect on different applications of unsharp measurements.

  9. Recent developments and proposed schemes for trapped ion frequency standards. [trapped mercury ions for microwave and optical frequency standards

    NASA Technical Reports Server (NTRS)

    Maleki, L.

    1982-01-01

    Ion traps are exciting candidates as future precision frequency sources. Recent developments demonstrate that mercury ion frequency standards are capable of a stability performance comparable to commercial cesium standards. There is, however, considerable room for improvement with regard to the signal to noise problem. The 40 GHz microwave frequency implies that a careful design should be implemented to ensure the elimination of the unwanted side bands in the microwave pump signal. A long life, high performance light source to be used in a trapped mercury ion microwave standard must be developed and the long term performance of a trapped mercury ion microwave standard must be investigated. While newly proposed two photon pumping schemes in conjuction with mercury ions promise exciting developments for both microwave and optical frequency standards, other ions that may be potential candidates should be evaluated for their usefulness.

  10. Experimental demonstration of a surface-electrode multipole ion trap

    NASA Astrophysics Data System (ADS)

    Maurice, Mark; Allen, Curtis; Green, Dylan; Farr, Andrew; Burke, Timothy; Hilleke, Russell; Clark, Robert

    2015-08-01

    We report on the design and experimental characterization of a surface-electrode multipole ion trap. Individual microscopic sugar particles are confined in the trap. The trajectories of driven particle motion are compared with a theoretical model, both to verify qualitative predictions of the model and to measure the charge-to-mass ratio of the confined particle. The generation of harmonics of the driving frequency is observed as a key signature of the nonlinear nature of the trap. We remark on possible applications of our traps, including to mass spectrometry.

  11. Deep optical trap for cold alkaline-Earth atoms.

    PubMed

    Cruz, Luciano S; Sereno, Milena; Cruz, Flavio C

    2008-03-01

    We describe a setup for a deep optical dipole trap or lattice designed for holding atoms at temperatures of a few mK, such as alkaline-Earth atoms which have undergone only regular Doppler cooling. We use an external optical cavity to amplify 3.2 W from a commercial single-frequency laser at 532 nm to 523 W. Powers of a few kW, attainable with low-loss optics or higher input powers, allow larger trap volumes for improved atom transfer from magneto-optical traps. We analyze possibilities for cooling inside the deep trap, the induced Stark shifts for calcium, and a cancellation scheme for the intercombination clock transition using an auxiliary laser. PMID:18542375

  12. Temperature and heating rate of ion crystals in Penning traps

    SciTech Connect

    Jensen, Marie J.; Hasegawa, Taro; Bollinger, John J.

    2004-09-01

    We have determined the temperature and heating rate of laser-cooled ions in a Penning trap using Doppler laser spectroscopy. Between 10{sup 4} and 10{sup 6} {sup 9}Be{sup +} ions are trapped in a Penning trap and Doppler laser cooled to temperatures of a few millikelvin, where they form ion crystals. This system is an example of a strongly coupled one-component plasma. The ion temperature was measured as a function of time after turning off the laser-cooling. In the solid phase, we measured a heating rate of {approx}65 mK/s. Information about possible heating mechanisms was obtained directly from temperature measurements, and also from measurements of the rate of radial expansion of the ion plasma. We determined that the observed heating is due to collisions with the {approx}4x10{sup -9} Pa residual gas of our vacuum system.

  13. Is the Penning Ion Trap Suitable for Quantum Computation?

    NASA Astrophysics Data System (ADS)

    Bollinger, J. J.; Kriesel, J. M.; Itano, W. M.; Mitchell, T. B.

    2001-10-01

    There is a great deal of interest in finding a physical system which can perform computations through quantum unitary operations and be scaled to large numbers of qubits. rf ion traps have been used in pioneering experiments on a few qubits. The Penning ion trap has some potential advantages compared to the rf trap. In rf traps, heating and decoherence rates of ion motional states have been observed to scale inversely with the size of the electrodes. Penning traps can have large electrodes while still retaining the large (5-10 MHz) motional frequencies required for quantum logic operations. This is because large static fields are more easily generated than large amplitude rf fields. Addressing of individual ions in the Penning trap is complicated by the plasma rotation, but should be possible with crystallized, planar plasmas controlled by a combination of rotating fields (a ``hard disk" geometry). We will discuss the pros and cons as well as some initial experiments to investigate the suitability of the Penning trap for quantum computation.

  14. Optical cavity integrated surface ion trap for enhanced light collection

    NASA Astrophysics Data System (ADS)

    Benito, Francisco M.

    Ion trap systems allow the faithful storage and manipulation of qubits encoded in the energy levels of the ions, and can be interfaced with photonic qubits that can be transmitted to connect remote quantum systems. Single photons transmitted from two remote sites, each entangled with one quantum memory, can be used to entangle distant quantum memories by interfering on a beam splitter. Efficient remote entanglement generation relies upon efficient light collection from single ions into a single mode fiber. This can be realized by integrating an ion trap with an optical cavity and employing the Purcell effect for enhancing the light collection. Remote entanglement can be used as a resource for a quantum repeater for provably secure long-distance communication or as a method for communicating within a distributed quantum information processor. We present the integration of a 1 mm optical cavity with a micro-fabricated surface ion trap. The plano-concave cavity is oriented normal to the chip surface where the planar mirror is attached underneath the trap chip. The cavity is locked using a 780 nm laser which is stabilized to Rubidium and shifted to match the 369 nm Doppler transition in Ytterbium. The linear ion trap allows ions to be shuttled in and out of the cavity mode. The Purcell enhancement of spontaneous emission into the cavity mode would then allow efficient collection of the emitted photons, enabling faster remote entanglement generation.

  15. Laser ablation loading of a surface-electrode ion trap

    SciTech Connect

    Leibrandt, David R.; Clark, Robert J.; Labaziewicz, Jaroslaw; Antohi, Paul; Bakr, Waseem; Brown, Kenneth R.; Chuang, Isaac L.

    2007-11-15

    We demonstrate loading of {sup 88}Sr{sup +} ions by laser ablation into a mm-scale surface-electrode ion trap. The laser used for ablation is a pulsed, frequency-tripled Nd:YAG with pulse energies of 1-10 mJ and durations of 4 ns. An additional laser is not required to photoionize the ablated material. The efficiency and lifetime of several candidate materials for the laser ablation target are characterized by measuring the trapped ion fluorescence signal for a number of consecutive loads. Additionally, laser ablation is used to load traps with a trap depth (40 meV) below where electron impact ionization loading is typically successful (> or approx. 500 meV)

  16. Towards Non-Equilibrium Dynamics with Trapped Ions

    NASA Astrophysics Data System (ADS)

    Silbert, Ariel; Jubin, Sierra; Doret, Charlie

    2016-05-01

    Atomic systems are superbly suited to the study of non-equilibrium dynamics. These systems' exquisite isolation from environmental perturbations leads to long relaxation times that enable exploration of far-from-equilibrium phenomena. One example of particular relevance to experiments in trapped ion quantum information processing, metrology, and precision spectroscopy is the approach to thermal equilibrium of sympathetically cooled linear ion chains. Suitable manipulation of experimental parameters permits exploration of the quantum-to-classical crossover between ballistic transport and diffusive, Fourier's Law conduction, a topic of interest not only to the trapped ion community but also for the development of microelectronic devices and other nanoscale structures. We present progress towards trapping chains of multiple co-trapped calcium isotopes geared towards measuring thermal equilibration and discuss plans for future experiments in non-equilibrium statistical mechanics. This work is supported by Cottrell College Science Award from the Research Corporation for Science Advancement and by Williams College.

  17. Photoelectron-photofragment coincidence spectroscopy in a cryogenically cooled linear electrostatic ion beam trap

    SciTech Connect

    Johnson, Christopher J.; Shen, Ben B.; Poad, Berwyck L. J.; Continetti, Robert E.

    2011-10-15

    A cryogenically cooled linear electrostatic ion beam trap for use in photoelectron-photofragment coincidence (PPC) spectroscopy is described. Using this instrument, anions created in cold, low-duty-cycle sources can be stored for many seconds in a {approx}20 K environment to cool radiatively, removing energetic uncertainties due to vibrationally excited precursor anions. This apparatus maintains a well-collimated beam necessary for high-resolution fragment imaging and the high experimental duty cycle needed for coincidence experiments. Ion oscillation is bunched and phase-locked to a modelocked laser, ensuring temporal overlap between ion bunches and laser pulses and that ions are intersected by the laser only when travelling in one direction. An electron detector is housed in the field-free center of the trap, allowing PPC experiments to be carried out on ions while they are stored and permitting efficient detection of 3-dimensional electron and neutral recoil trajectories. The effects of trapping parameters on the center-of-mass trajectories in the laser-ion interaction region are explored to optimize neutral particle resolution, and the impact of bunching on ion oscillation is established. Finally, an initial demonstration of radiative cooling is presented.

  18. Mountain cold-trapping increases transfer of persistent organic pollutants from atmosphere to cows' milk.

    PubMed

    Shunthirasingham, Chubashini; Wania, Frank; MacLeod, Matthew; Lei, Ying Duan; Quinn, Cristina L; Zhang, Xianming; Scheringer, Martin; Wegmann, Fabio; Hungerbühler, Konrad; Ivemeyer, Silvia; Heil, Fritz; Klocke, Peter; Pacepavicius, Grazina; Alaee, Mehran

    2013-08-20

    Concentrations of long-lived organic contaminants in snow, soil, lake water, and vegetation have been observed to increase with altitude along mountain slopes. Such enrichment, called "mountain cold-trapping", is attributed to a transition from the atmospheric gas phase to particles, rain droplets, snowflakes, and Earth's surface at the lower temperatures prevailing at higher elevations. Milk sampled repeatedly from cows that had grazed at three different altitudes in Switzerland during one summer was analyzed for a range of persistent organic pollutants. Mountain cold-trapping significantly increased air-to-milk transfer factors of most analytes. As a result, the milk of cows grazing at higher altitudes was more contaminated with substances that have regionally uniform air concentrations (hexachlorobenzene, α-hexachlorocyclohexane, endosulfan sulfate). For substances that have sources, and therefore higher air concentrations, at lower altitudes (polychlorinated biphenyls, γ-hexachlorocyclohexane), alpine milk has lower concentrations, but not as low as would be expected without mountain cold-trapping. Differences in the elevational gradients in soil concentrations and air-to-milk transfer factors highlight that cold-trapping of POPs in pastures is mostly due to increased gas-phase deposition as a result of lower temperatures causing higher uptake capacity of plant foliage, whereas cold-trapping in soils more strongly depends on wet and dry particle deposition. Climatic influences on air-to-milk transfer of POPs needs to be accounted for when using contamination of milk lipids to infer contamination of the atmosphere. PMID:23885857

  19. Magnetic levitation for effective loading of cold cesium atoms in a crossed dipole trap

    NASA Astrophysics Data System (ADS)

    Li, Yuqing; Feng, Guosheng; Xu, Rundong; Wang, Xiaofeng; Wu, Jizhou; Chen, Gang; Dai, Xingcan; Ma, Jie; Xiao, Liantuan; Jia, Suotang

    2015-05-01

    We report a detailed study of effective magnetically levitated loading of cold atoms in a crossed dipole trap: an appropriate magnetic field gradient precisely compensates for the destructive gravitational force of the atoms and an additional bias field simultaneously eliminates the antitrapping potential induced by the magnetic field gradient. The magnetic levitation is required for a large-volume crossed dipole trap to form a shallow but very effective loading potential, making it a promising method for loading and trapping more cold atoms. For cold cesium atoms in the F =3 , m F =3 state prepared by three-dimensional degenerated Raman sideband cooling, a large number of atoms ˜3.2 ×106 have been loaded into a large-volume crossed dipole trap with the help of the magnetic levitation technique. The dependence of the number of atoms loaded and trapped in the dipole trap on the magnetic field gradient and bias field, respectively, is in good agreement with the theoretical analysis. The optimum magnetic field gradient of 31.13 G/cm matches the theoretical value of 31.3 G/cm well. This method can be used to obtain more cold atoms or a large number of Bose-Einstein condensation atoms for many atomic species in high-field seeking states.

  20. Toward Quantum Simulation with 9Be+ Ions in a Penning Trap

    NASA Astrophysics Data System (ADS)

    Sawyer, Brian; Britton, Joe; Uys, Hermann; Biercuk, Michael; Bollinger, John

    2011-05-01

    Experimental progress in the fields of atomic and molecular physics has allowed exquisite control over ensembles of cold and ultracold ions, neutral atoms, and polar molecules. A number of theoretical proposals have been put forward concerning direct simulation of quantum Hamiltonians in these systems. We report progress toward simulation of the transverse Ising model in a two-dimensional Coulomb crystal of ~100 9Be+ ions confined within a Penning trap. Coupling between ions is controlled via optical dipole forces, thereby facilitating a wide range of interparticle interactions including infinite-range and nearest-neighbor coupling. Furthermore, the triangular lattice structure readily obtained within the planar Coulomb crystal allows for simulation of spin frustration in an antiferromagnetic system. Given our large ensembles of trapped 9Be+, it may be possible to perform quantum simulations that are currently intractable with classical computers. We acknowledge funding support from the DARPA OLE program.

  1. Heavy ion plasma confinement in an RF quadrupole trap

    NASA Technical Reports Server (NTRS)

    Schermann, J.; Major, F. G.

    1971-01-01

    The confinement of an electron free plasma in a pure quadrupole RF electric trap was considered. The ultimate goal was to produce a large density of mercury ions, in order to realize a trapped ion frequency standard using the hyperfine resonance of 199 Hg(+) at 40.7 GHz. An attempt was made to obtain an iodine plasma consisting of equal numbers of positive and negative ions of atomic iodine, the positive iodine ions, being susceptible to charge-exchange with mercury atoms, will produce the desired mercury ions. The experiment showed that the photoproduction of ions pairs in iodine using the necessary UV radiation occurs with a small cross-section, making it difficult to demonstrate the feasibility of space charge neutralization in a quadrupole trap. For this reason it was considered expedient to choose thallium iodide, which has a more favorable absorption spectrum (in the region of 2000 to 2100 A). The results indicate that, although the ionic recombination is a serious limiting factor, a considerable improvement can be obtained in practice for the density of trapped ions, with a considerable advantage in lifetimes for spectroscopic purposes. The ion pair formation by photoionization is briefly reviewed.

  2. Trapped-ion antennae for the transmission of quantum information.

    PubMed

    Harlander, M; Lechner, R; Brownnutt, M; Blatt, R; Hänsel, W

    2011-03-10

    More than 100 years ago, Hertz succeeded in transmitting signals over a few metres to a receiving antenna using an electromagnetic oscillator, thus proving the electromagnetic theory developed by Maxwell. Since this seminal work, technology has developed, and various oscillators are now available at the quantum mechanical level. For quantized electromagnetic oscillations, atoms in cavities can be used to couple electric fields. However, a quantum mechanical link between two mechanical oscillators (such as cantilevers or the vibrational modes of trapped atoms or ions) has been rarely demonstrated and has been achieved only indirectly. Examples include the mechanical transport of atoms carrying quantum information or the use of spontaneously emitted photons. Here we achieve direct coupling between the motional dipoles of separately trapped ions over a distance of 54 micrometres, using the dipole-dipole interaction as a quantum mechanical transmission line. This interaction is small between single trapped ions, but the coupling is amplified by using additional trapped ions as antennae. With three ions in each well, the interaction is increased by a factor of seven compared to the single-ion case. This enhancement facilitates bridging of larger distances and relaxes the constraints on the miniaturization of trap electrodes. The system provides a building block for quantum computers and opportunities for coupling different types of quantum systems. PMID:21346764

  3. A Linear RFQ Ion Trap for the Enriched Xenon Observatory

    SciTech Connect

    Flatt, B.; Green, M.; Wodin, J.; DeVoe, R.; Fierlinger, P.; Gratta, G.; LePort, F.; Montero Diez, M.; Neilson, R.; O'Sullivan, K.; Pocar, A.; Baussan, E.; Breidenbach, M.; Conley, R.; Fairbank Jr., W.; Farine, J.; Hall, K.; Hallman, D.; Hargrove, C.; Hauger, M.; Hodgson, J.; /Stanford U., Phys. Dept. /Neuchatel U. /SLAC /Colorado State U. /Laurentian U. /Carleton U. /Alabama U.

    2008-01-14

    The design, construction, and performance of a linear radio-frequency ion trap (RFQ) intended for use in the Enriched Xenon Observatory (EXO) are described. EXO aims to detect the neutrinoless double-beta decay of {sup 136}Xe to {sup 136}Ba. To suppress possible backgrounds EXO will complement the measurement of decay energy and, to some extent, topology of candidate events in a Xe filled detector with the identification of the daughter nucleus ({sup 136}Ba). The ion trap described here is capable of accepting, cooling, and confining individual Ba ions extracted from the site of the candidate double-beta decay event. A single trapped ion can then be identified, with a large signal-to-noise ratio, via laser spectroscopy.

  4. A model of optical trapping cold atoms using a metallic nano wire with surface plasmon effect

    NASA Astrophysics Data System (ADS)

    Thi Phuong Lan, Nguyen; Thi Nga, Do; Viet, Nguyen Ai

    2016-06-01

    In this work, we construct a new model of optical trapping cold atoms with a metallic nano wire by using surface plasmon effect generated by strong field of laser beams. Using the skin effect, we send a strong oscillated electromagnetic filed through the surface of a metallic nano wire. The local field generated by evanescent effect creates an effective attractive potential near the surface of metallic nano wires. The consideration of some possible boundary and frequency conditions might lead to non-trivial bound state solution for a cold atom. We discus also the case of the laser reflection optical trap with shell-core design, and compare our model with another recent schemes of cold atom optical traps using optical fibers and carbon nanotubes.

  5. Tritium removal from NaK-cold traps; First results on hydride precipitation kinetics

    SciTech Connect

    Reimann, J.; Kirchner, R.; Pfeff, M.; Rackel, D. )

    1992-03-01

    This paper discusses tritium removal from a self-cooled Pb-17Li blanket of a fusion reactor, permeation into an intermediate NaK loop and precipitation of the tritide in a cold trap. First experiments on the kinetics of hydride precipitation showed that low supersaturation concentrations are obtained at low concentration ranges, these values are obtained after a very short cold trap loading period. Both results meet essential requirements for fusion blanket cold traps. Theoretical work has shown that two-dimensional calculations (including buoyancy effects) of the temperature, velocity and concentration distributions result in precipitation distributions which differ significantly form these obtained with 1d-models currently used to develop mass transfer relationships.

  6. Parallel Transport Quantum Logic Gates with Trapped Ions.

    PubMed

    de Clercq, Ludwig E; Lo, Hsiang-Yu; Marinelli, Matteo; Nadlinger, David; Oswald, Robin; Negnevitsky, Vlad; Kienzler, Daniel; Keitch, Ben; Home, Jonathan P

    2016-02-26

    We demonstrate single-qubit operations by transporting a beryllium ion with a controlled velocity through a stationary laser beam. We use these to perform coherent sequences of quantum operations, and to perform parallel quantum logic gates on two ions in different processing zones of a multiplexed ion trap chip using a single recycled laser beam. For the latter, we demonstrate individually addressed single-qubit gates by local control of the speed of each ion. The fidelities we observe are consistent with operations performed using standard methods involving static ions and pulsed laser fields. This work therefore provides a path to scalable ion trap quantum computing with reduced requirements on the optical control complexity. PMID:26967401

  7. Parallel Transport Quantum Logic Gates with Trapped Ions

    NASA Astrophysics Data System (ADS)

    de Clercq, Ludwig E.; Lo, Hsiang-Yu; Marinelli, Matteo; Nadlinger, David; Oswald, Robin; Negnevitsky, Vlad; Kienzler, Daniel; Keitch, Ben; Home, Jonathan P.

    2016-02-01

    We demonstrate single-qubit operations by transporting a beryllium ion with a controlled velocity through a stationary laser beam. We use these to perform coherent sequences of quantum operations, and to perform parallel quantum logic gates on two ions in different processing zones of a multiplexed ion trap chip using a single recycled laser beam. For the latter, we demonstrate individually addressed single-qubit gates by local control of the speed of each ion. The fidelities we observe are consistent with operations performed using standard methods involving static ions and pulsed laser fields. This work therefore provides a path to scalable ion trap quantum computing with reduced requirements on the optical control complexity.

  8. Global gyrokinetic simulations of trapped-electron mode and trapped-ion mode microturbulence

    NASA Astrophysics Data System (ADS)

    Drouot, T.; Gravier, E.; Reveille, T.; Sarrat, M.; Collard, M.; Bertrand, P.; Cartier-Michaud, T.; Ghendrih, P.; Sarazin, Y.; Garbet, X.

    2015-08-01

    This paper presents a reduced kinetic model, which describes simultaneously trapped-ion (TIM) and trapped-electron (TEM) driven modes. Interestingly, the model enables the study of a full f problem for ion and electron trapped particles at very low numerical cost. The linear growth rate obtained with the full f nonlinear code Trapped Element REduction in Semi Lagrangian Approach is successfully compared with analytical predictions. Moreover, nonlinear results show some basic properties of collisionless TEM and TIM turbulence in tokamaks. A competition between streamer-like structures and zonal flows is observed for TEM and TIM turbulence. Zonal flows are shown to play an important role in suppressing the nonlinear transport and strongly depend on the temperature ratio Te/Ti .

  9. Nonlinear propagation of dust-ion-acoustic solitary waves in an unmagnetized dusty plasma with trapped particle distribution

    NASA Astrophysics Data System (ADS)

    Rahman, O.

    2015-12-01

    The nonlinear propagation of dust-ion-acoustic (DIA) solitary waves (SWs) in an unmagnetized four-component dusty plasma containing electrons and negative ions obeying vortex-like (trapped) velocity distribution, cold mobile positive ions and arbitrarily charged stationary dust has been theoretically investigated. The properties of small but finite amplitude DIASWs are studied by employing the reductive perturbation technique. It has been found that owing to the departure from the Maxwellian electron and Maxwellian negative ion distribution to a vortex-like one, the dynamics of such DIASWs is governed by a modified Korteweg-de Vries (mKdV) equation which admits SW solution under certain conditions. The basic properties (speed, amplitude, width, etc.) of such DIASWs are found to be significantly modified by the presence of trapped electron and trapped negative ions. The implications of our results to space and laboratory dusty electronegative plasmas (DENPs) are briefly discussed.

  10. Collisional activation with random noise in ion trap mass spectrometry

    SciTech Connect

    McLuckey, S.A.; Goeringer, D.E.; Glish, G.L.

    1992-07-01

    Random noise applied to the end caps of a quadrupole ion trap is shown to be an effective means for the collisional activation of trapped ions independent of mass/charge ratio and number of ions. This technique is compared and contrasted with conventional single-frequency collisional activation for the molecular ion of N,N-dimethylaniline, protonated cocaine, the molecular anion of 2,4,6-trinitrotoluene, and doubly protonated neuromedin U-8. Collisional activation with noise tends to produce more extensive fragmentation than the conventional approach due to the fact that product ions are also kinetically excited in the noise experiment. The efficiency of the noise experiment in producing detectable product ions relative to the conventional approach ranges from being equivalent to being a factor of 3 less efficient. Furthermore, discrimination against low mass/charge product ions is apparent in the data from multiply charged biomolecules. Nevertheless, collisional activation with random noise provides a very simple means for overcoming problems associated with the dependence of single-frequency collisional activation on mass/charge ratio and the number of ions in the ion trap. 45 refs., 7 figs.

  11. Resonant interaction of trapped cold atoms with a magnetic cantilever tip

    NASA Astrophysics Data System (ADS)

    Montoya, Cris; Valencia, Jose; Geraci, Andrew A.; Eardley, Matthew; Moreland, John; Hollberg, Leo; Kitching, John

    2015-06-01

    Magnetic resonance in an ensemble of laser-cooled trapped Rb atoms is excited using a microcantilever with a magnetic tip. The cantilever is mounted on a multilayer chip designed to capture, cool, and magnetically transport cold atoms. The coupling is observed by measuring the loss from a magnetic trap as the oscillating cantilever induces Zeeman-state transitions in the atoms. Interfacing cold atoms with mechanical devices could enable probing and manipulating atomic spins with nanometer spatial resolution and single-spin sensitivity, leading to new capabilities in quantum computation, quantum simulation, and precision sensing.

  12. The magnetic trapping mode of an electron beam ion trap: New opportunities for highly charged ion research

    SciTech Connect

    Beiersdorfer, P.; Schweikhard, L.; Lopez-Urrutia, J.C.; Widmann, K.

    1996-11-01

    Using x-ray spectroscopic techniques, we have investigated the properties of an electron beam ion trap (EBIT) after the electron beam is switched off. In the absence of the electron beam, bare, and hydrogenlike Kr{sup 35+} and Kr{sup 36+} ions remain trapped due to externally applied magnetic and electric fields for at least 5 s; xenon ions with an open {ital L} shell, i.e., Xe{sup 45+}{endash}Xe{sup 52+}, remain trapped at least as long as 20 s. The ion storage time in this {open_quote}{open_quote}magnetic trapping mode{close_quote}{close_quote} depends on the pressure of background atoms as well as on the value of the externally applied trapping potential, and even longer ion storage times appear possible. The magnetic trapping mode enables a variety of new opportunities for atomic physics research involving highly charged ions, which include the study of charge transfer reactions, Doppler-shift-free measurements of the Lamb shift, measurements of radiative lifetimes of long-lived metastable levels, or ion-ion collision studies, by x-ray or laser spectroscopy, and mass spectrometry. Because the trap is filled {ital in} {ital situ} during the electron trapping phase, transfer losses associated with filling the trap from an external source are avoided. We present spectra of the {ital K}-shell emission from heliumlike and hydrogenlike Kr{sup 34+} and Kr{sup 35+} as well as Xe{sup 52+} and Xe{sup 53+} that are produced by charge transfer reactions in collisions between ions and neutral atoms. Marked differences with {ital K}-shell spectra produced by electron-impact excitation are evident. We use the measurements to infer the Lamb shift contribution to the energy of the 1{ital s}{sub 1/2}{endash}2{ital p}{sub 3/2} transition in hydrogenlike Xe{sup 53+} and determine it to be 31276(12) eV. The measurement technique can be applied to any ion produced in an EBIT so that Doppler-shift-free Lamb shift measurements of hydrogenlike U{sup 91+} are within reach.

  13. T-junction ion trap array for two-dimensional ion shuttling, storage, and manipulation

    SciTech Connect

    Hensinger, W.K.; Olmschenk, S.; Stick, D.; Hucul, D.; Yeo, M.; Acton, M.; Deslauriers, L.; Monroe, C.; Rabchuk, J.

    2006-01-16

    We demonstrate a two-dimensional 11-zone ion trap array, where individual laser-cooled atomic ions are stored, separated, shuttled, and swapped. The trap geometry consists of two linear rf-ion trap sections that are joined at a 90 deg. angle to form a T-shaped structure. We shuttle a single ion around the corners of the T-junction and swap the positions of two crystallized ions using voltage sequences designed to accommodate the nontrivial electrical potential near the junction. Full two-dimensional control of multiple ions demonstrated in this system may be crucial for the realization of scalable ion trap quantum computation and the implementation of quantum networks.

  14. Ion Trapping, Storage, and Ejection in Structures for Lossless Ion Manipulations.

    PubMed

    Zhang, Xinyu; Garimella, Sandilya V B; Prost, Spencer A; Webb, Ian K; Chen, Tsung-Chi; Tang, Keqi; Tolmachev, Aleksey V; Norheim, Randolph V; Baker, Erin S; Anderson, Gordon A; Ibrahim, Yehia M; Smith, Richard D

    2015-06-16

    A new Structures for Lossless Ion Manipulations (SLIM) module, having electrode arrays patterned on a pair of parallel printed circuit boards (PCB), was constructed and utilized to investigate capabilities for ion trapping at a pressure of 4 Torr. Positive ions were confined by application of RF voltages to a series of inner rung electrodes with alternating phase on adjacent electrodes, in conjunction with positive DC potentials on surrounding guard electrodes on each PCB. An axial DC field was also introduced by stepwise varying the DC potentials applied to the inner rung electrodes to control the ion transport and accumulation inside the ion trapping region. We show that ions can be trapped and accumulated with up to 100% efficiency, stored for at least 5 h with no significant losses, and then could be rapidly ejected from the SLIM trap. The present results provide a foundation for the development of much more complex SLIM devices that facilitate extended ion manipulations. PMID:25971536

  15. Electrostatic particle trap for ion beam sputter deposition

    DOEpatents

    Vernon, Stephen P.; Burkhart, Scott C.

    2002-01-01

    A method and apparatus for the interception and trapping of or reflection of charged particulate matter generated in ion beam sputter deposition. The apparatus involves an electrostatic particle trap which generates electrostatic fields in the vicinity of the substrate on which target material is being deposited. The electrostatic particle trap consists of an array of electrode surfaces, each maintained at an electrostatic potential, and with their surfaces parallel or perpendicular to the surface of the substrate. The method involves interception and trapping of or reflection of charged particles achieved by generating electrostatic fields in the vicinity of the substrate, and configuring the fields to force the charged particulate material away from the substrate. The electrostatic charged particle trap enables prevention of charged particles from being deposited on the substrate thereby enabling the deposition of extremely low defect density films, such as required for reflective masks of an extreme ultraviolet lithography (EUVL) system.

  16. Investigation of nonextensivity trapped electrons effect on the solitary ion-acoustic wave using fractional Schamel equation

    NASA Astrophysics Data System (ADS)

    Nazari-Golshan, A.

    2016-08-01

    Ion-acoustic (IA) solitary wave propagation is investigated by solving the fractional Schamel equation (FSE) in a homogenous system of unmagnetized plasma. This plasma consists of the nonextensive trapped electrons and cold fluid ions. The effects of the nonextensive q-parameter, electron trapping, and fractional parameter have been studied. The FSE is derived by using the semi-inverse and Agrawal's methods. The analytical results show that an increase in the amount of electron trapping and nonextensive q-parameter increases the soliton ion-acoustic amplitude in agreement with the previously obtained results. However, it is vice-versa for the fractional parameter. This feature leads to the fact that the fractional parameter may be used to increase the IA soliton amplitude instead of increasing electron trapping and nonextensive parameters.

  17. Characteristics of Ion Activation and Collision Induced Dissociation Using Digital Ion Trap Technology.

    PubMed

    Xu, Fuxing; Dang, Qiankun; Dai, Xinhua; Fang, Xiang; Wang, Yuanyuan; Ding, Li; Ding, Chuan-Fan

    2016-08-01

    Collision induced dissociation (CID) is one of the most established techniques for tandem mass spectrometry analysis. The CID of mass selected ion could be realized by ion resonance excitation with a digital rectangular waveform. The method is simple, and highly efficient CID result could be obtained by optimizing the experimental parameters, such as digital waveform voltage, frequency, and q value. In this work, the relationship between ion trapping waveform voltage and frequency at preselected q value, the relationship between waveform frequency and the q value at certain ion trapping voltage for optimum CID efficiency were investigated. Experiment results showed that the max CID efficiency of precursor reserpine ions can be obtained at different trapping waveform voltage and frequency when q and β are different. Based on systematic experimental analysis, the optimum experimental conditions for high CID efficiency can be calculated at any selected β or q. By using digital ion trap technology, the CID process and efficient fragmentation of parent ions can be realized by simply changing the trapping waveform amplitude, frequency, and the β values in the digital ion trap mass spectrometry. The technology and method are simple. It has potential use in ion trap mass spectrometry. Graphical Abstract ᅟ. PMID:27150507

  18. Characteristics of Ion Activation and Collision Induced Dissociation Using Digital Ion Trap Technology

    NASA Astrophysics Data System (ADS)

    Xu, Fuxing; Dang, Qiankun; Dai, Xinhua; Fang, Xiang; Wang, Yuanyuan; Ding, Li; Ding, Chuan-Fan

    2016-08-01

    Collision induced dissociation (CID) is one of the most established techniques for tandem mass spectrometry analysis. The CID of mass selected ion could be realized by ion resonance excitation with a digital rectangular waveform. The method is simple, and highly efficient CID result could be obtained by optimizing the experimental parameters, such as digital waveform voltage, frequency, and q value. In this work, the relationship between ion trapping waveform voltage and frequency at preselected q value, the relationship between waveform frequency and the q value at certain ion trapping voltage for optimum CID efficiency were investigated. Experiment results showed that the max CID efficiency of precursor reserpine ions can be obtained at different trapping waveform voltage and frequency when q and β are different. Based on systematic experimental analysis, the optimum experimental conditions for high CID efficiency can be calculated at any selected β or q. By using digital ion trap technology, the CID process and efficient fragmentation of parent ions can be realized by simply changing the trapping waveform amplitude, frequency, and the β values in the digital ion trap mass spectrometry. The technology and method are simple. It has potential use in ion trap mass spectrometry.

  19. Characteristics of Ion Activation and Collision Induced Dissociation Using Digital Ion Trap Technology

    NASA Astrophysics Data System (ADS)

    Xu, Fuxing; Dang, Qiankun; Dai, Xinhua; Fang, Xiang; Wang, Yuanyuan; Ding, Li; Ding, Chuan-Fan

    2016-05-01

    Collision induced dissociation (CID) is one of the most established techniques for tandem mass spectrometry analysis. The CID of mass selected ion could be realized by ion resonance excitation with a digital rectangular waveform. The method is simple, and highly efficient CID result could be obtained by optimizing the experimental parameters, such as digital waveform voltage, frequency, and q value. In this work, the relationship between ion trapping waveform voltage and frequency at preselected q value, the relationship between waveform frequency and the q value at certain ion trapping voltage for optimum CID efficiency were investigated. Experiment results showed that the max CID efficiency of precursor reserpine ions can be obtained at different trapping waveform voltage and frequency when q and β are different. Based on systematic experimental analysis, the optimum experimental conditions for high CID efficiency can be calculated at any selected β or q. By using digital ion trap technology, the CID process and efficient fragmentation of parent ions can be realized by simply changing the trapping waveform amplitude, frequency, and the β values in the digital ion trap mass spectrometry. The technology and method are simple. It has potential use in ion trap mass spectrometry.

  20. Scheme for teleportation of unknown states of trapped ion

    NASA Astrophysics Data System (ADS)

    Chen, Mei-Feng; Ma, Song-She

    2008-02-01

    A scheme is presented for teleporting an unknown state in a trapped ion system. The scheme only requires a single laser beam. It allows the trap to be in any state with a few phonons, e.g. a thermal motion. Furthermore, it works in the regime, where the Rabi frequency of the laser is on the order of the trap frequency. Thus, the teleportation speed is greatly increased, which is important for decreasing the decoherence effect. This idea can also be used to teleport an unknown ionic entangled state.

  1. Towards Laser Cooling Trapped Ions with Telecom Light

    NASA Astrophysics Data System (ADS)

    Dungan, Kristina; Becker, Patrick; Donoghue, Liz; Liu, Jackie; Olmschenk, Steven

    2015-05-01

    Quantum information has many potential applications in communication, atomic clocks, and the precision measurement of fundamental constants. Trapped ions are excellent candidates for applications in quantum information because of their isolation from external perturbations, and the precise control afforded by laser cooling and manipulation of the quantum state. For many applications in quantum communication, it would be advantageous to interface ions with telecom light. We present progress towards laser cooling and trapping of doubly-ionized lanthanum, which should require only infrared, telecom-compatible light. Additionally, we present progress on optimization of a second-harmonic generation cavity for laser cooling and trapping barium ions, for future sympathetic cooling experiments. This research is supported by the Army Research Office, Research Corporation for Science Advancement, and Denison University.

  2. Single Ion Trapping for the Enriched Xenon Observatory

    SciTech Connect

    Waldman, Samuel J.; /Stanford U., Phys. Dept. /SLAC

    2006-03-28

    In the last decade, a variety of neutrino oscillation experiments have established that there is a mass difference between neutrino flavors, without determining the absolute neutrino mass scale. The Enriched Xenon Observatory for neutrinoless double beta decay (EXO) will search for the rare decays of xenon to determine the absolute value of the neutrino mass. The experiment uses a novel technique to minimize backgrounds, identifying the decay daughter product in real time using single ion spectroscopy. Here, we describe single ion trapping and spectroscopy compatible with the EXO detector. We extend the technique of single ion trapping in ultrahigh vacuum to trapping in xenon gas. With this technique, EXO will achieve a neutrino mass sensitivity of {approx_equal} .010 eV.

  3. Laser desorption in an ion trap mass spectrometer

    SciTech Connect

    Eiden, G.C.; Cisper, M.E.; Alexander, M.L.; Hemberger, P.H.; Nogar, N.S.

    1993-02-01

    Laser desorption in a ion-trap mass spectrometer shows significant promise for both qualitative and trace analysis. Several aspects of this methodology are discussed in this work. We previously demonstrated the generation of both negative and positive ions by laser desorption directly within a quadrupole ion trap. In the present work, we explore various combinations of d.c., r.f., and time-varying fields in order to optimize laser generated signals. In addition, we report on the application of this method to analyze samples containing compounds such as amines, metal complexes, carbon clusters, and polynuclear aromatic hydrocarbons. In some cases the ability to rapidly switch between positive and negative ion modes provides sufficient specificity to distinguish different compounds of a mixture with a single stage of mass spectrometry. In other experiments, we combined intensity variation studies with tandem mass spectrometry experiments and positive and negative ion detection to further enhance specificity.

  4. Laser ablation loading of a radiofrequency ion trap

    NASA Astrophysics Data System (ADS)

    Zimmermann, K.; Okhapkin, M. V.; Herrera-Sancho, O. A.; Peik, E.

    2012-06-01

    The production of ions via laser ablation for the loading of radiofrequency (RF) ion traps is investigated using a nitrogen laser with a maximum pulse energy of 0.17 mJ and a peak intensity of about 250 MW/cm2. A time-of-flight mass spectrometer is used to measure the ion yield and the distribution of the charge states. Singly charged ions of elements that are presently considered for the use in optical clocks or quantum logic applications could be produced from metallic samples at a rate of the order of magnitude 105 ions per pulse. A linear Paul trap was loaded with Th+ ions produced by laser ablation. An overall ion production and trapping efficiency of 10-7 to 10-6 was attained. For ions injected individually, a dependence of the capture probability on the phase of the RF field has been predicted. In the experiment this was not observed, presumably because of collective effects within the ablation plume.

  5. Towards ultra-cold Bose-Fermi mixtures in a micro-magnetic trap

    NASA Astrophysics Data System (ADS)

    Aubin, S.

    2005-05-01

    We present progress on producing quantum degenerate fermionic potassium (^40K) and bosonic rubidium (^87Rb) gases in a micro-magnetic chip trap. The two atomic species are cooled and trapped simultaneously in a vapor loaded magneto-optical trap (MOT). The cold two-species atomic cloud is transported in a quadrupole magnetic trap to the surface of a chip, where it is loaded into a micro-magnetic trap. In optimizing the loading process, we developed an optical probe with high signal-to-noise for mapping out the minima of the micro-magnetic field by creating a 1D MOT at the surface of the chip. We have seen evidence of RF evaporation and are working towards quantum degeneracy. This approach to degeneracy requires only a single chamber, because the rapid evaporative cooling due to the tight confinement of the chip trap relaxes the stringent vacuum requirements of a traditional magnetic trap. In describing our experimental approach, we address the experimental challenges related to microtrapping fermions and future studies of cold Fermi gases. Work supported by NSERC, CFI, PRO, and OIT.

  6. Next Generation JPL Ultra-Stable Trapped Ion Atomic Clocks

    NASA Technical Reports Server (NTRS)

    Burt, Eric; Tucker, Blake; Larsen, Kameron; Hamell, Robert; Tjoelker, Robert

    2013-01-01

    Over the past decade, trapped ion atomic clock development at the Jet Propulsion Laboratory (JPL) has focused on two directions: 1) new atomic clock technology for space flight applications that require strict adherence to size, weight, and power requirements, and 2) ultra-stable atomic clocks, usually for terrestrial applications emphasizing ultimate performance. In this paper we present a new ultra-stable trapped ion clock designed, built, and tested in the second category. The first new standard, L10, will be delivered to the Naval Research Laboratory for use in characterizing DoD space clocks.

  7. Ion Trapping, Storage, and Ejection in Structures for Lossless Ion Manipulations

    SciTech Connect

    Zhang, Xinyu; Garimella, Venkata BS; Prost, Spencer A.; Webb, Ian K.; Chen, Tsung-Chi; Tang, Keqi; Tolmachev, Aleksey V.; Norheim, Randolph V.; Baker, Erin Shammel; Anderson, Gordon A.; Ibrahim, Yehia M.; Smith, Richard D.

    2015-06-16

    A structure for lossless ion manipulation (SLIM) module was constructed with electrode arrays patterned on a pair of parallel printed circuit boards (PCB) separated by 5 mm and utilized to investigate capabilities for ion trapping at 4 Torr. Positive ions were confined by application of RF having alternating phases on a series of inner rung electrodes and by positive DC potentials on surrounding guard electrodes on each PCB. An axial DC field was also introduced by stepwise varying the DC potential of the inner rung electrodes so as to control the ion transport and accumulation inside the ion trap. We show that ions could be trapped and accumulated with 100% efficiency, stored for at least 5 hours with no losses, and could be rapidly ejected from the SLIM trap.

  8. Laser-based studies with an ion-trap mass spectrometer: Ion tomography and analytical applications

    NASA Astrophysics Data System (ADS)

    Alexander, M. L.; Cisper, M. E.; Hemberger, P. H.; Nogar, N. S.; Williams, J. D.; Syka, J. E. P.

    The iron trap mass spectrometer (ITMS) is an ion storage device which consists of two hyperbolic endcaps and a hyperbolic ring electrode. This forms a trapping cavity having a volume of several cm(sup 3). An RF potential applied to the ring electrode produces a time-varying potential which can be used to trap and/or manipulate ions under controlled conditions. This device has been used in ion trapping studies for a number of years. More recently, a commercial version has been produced and sold which allows for mass-selective ejection of trapped ions, with subsequent detection by an electron multiplier. In this mode, it operates as a compact, high efficiency, high resolution mass spectrometer. The instrument has found applications in GC/MS, in tandem mass spectroscopy and in portable mass spectral analysis. In this manuscript, we present a survey of recent results incorporating laser desorption, ionization, or photodissociation with ITMS. In one instance, we describe the use of laser photodissociation to map the spatial distribution of trapped ions in the ITMS. In this tomographic study, we have parameterized the effects of trapping potential, buffer gas pressure, supplementary RF-potential, and laser intensity. In separate studies, laser desorption was used to generate gas phase ions in the ITMS from a solid probe, by irradiation of both neat and matrix-dissolved samples. The latter experiment produced both high molecular weight ions and significant numbers of negative ions.

  9. Incomplete optical shielding in cold sodium atom traps

    SciTech Connect

    Yurovsky, Vladimir; Ben-Reuven, Abraham

    1997-01-05

    A simple two-channel model, based on the semiclassical Landau-Zener (LZ) approximation, with averaging over angle-dependent exponents, is proposed as a fast means for accounting for the incomplete optical shielding of collisions, as observed in recent experiments conducted by Weiner and co-workers on ultracold sodium-atom traps, and its dependence on the laser polarization. The model yields a reasonably good agreement with the recent quantum close-coupling calculations of Julienne and co-workers. The remaining discrepancy between both theories and the data is qualitatively attributed to a partial overlap of the collision ranges at which loss processes and optical shielding occur.

  10. The uses of electron beam ion traps in the study of highly charged ions

    SciTech Connect

    Knapp, D.

    1994-11-02

    The Electron Beam Ion Trap (EBIT) is a relatively new tool for the study of highly charged ions. Its development has led to a variety of new experimental opportunities; measurements have been performed with EBITs using techniques impossible with conventional ion sources or storage rings. In this paper, I will highlight the various experimental techniques we have developed and the results we have obtained using the EBIT and higher-energy Super-EBIT built at the Lawrence Livermore National Laboratory. The EBIT employs a high-current-density electron beam to trap, ionize, and excite a population of ions. The ions can be studied in situ or extracted from the trap for external experiments. The trapped ions form an ionization-state equilibrium determined by the relative ionization and recombination rates. Ions of several different elements may simultaneously be present in the trap. The ions are nearly at rest, and, for most systems, all in their ground-state configurations. The electron-ion interaction energy has a narrow distribution and can be varied over a wide range. We have used the EBIT devices for the measurement of electron-ion interactions, ion structure, ion-surface interactions, and the behavior of low-density plasmas.

  11. Verification of high efficient broad beam cold cathode ion source.

    PubMed

    Abdel Reheem, A M; Ahmed, M M; Abdelhamid, M M; Ashour, A H

    2016-08-01

    An improved form of cold cathode ion source has been designed and constructed. It consists of stainless steel hollow cylinder anode and stainless steel cathode disc, which are separated by a Teflon flange. The electrical discharge and output characteristics have been measured at different pressures using argon, nitrogen, and oxygen gases. The ion exit aperture shape and optimum distance between ion collector plate and cathode disc are studied. The stable discharge current and maximum output ion beam current have been obtained using grid exit aperture. It was found that the optimum distance between ion collector plate and ion exit aperture is equal to 6.25 cm. The cold cathode ion source is used to deposit aluminum coating layer on AZ31 magnesium alloy using argon ion beam current which equals 600 μA. Scanning electron microscope and X-ray diffraction techniques used for characterizing samples before and after aluminum deposition. PMID:27587108

  12. Verification of high efficient broad beam cold cathode ion source

    NASA Astrophysics Data System (ADS)

    Abdel Reheem, A. M.; Ahmed, M. M.; Abdelhamid, M. M.; Ashour, A. H.

    2016-08-01

    An improved form of cold cathode ion source has been designed and constructed. It consists of stainless steel hollow cylinder anode and stainless steel cathode disc, which are separated by a Teflon flange. The electrical discharge and output characteristics have been measured at different pressures using argon, nitrogen, and oxygen gases. The ion exit aperture shape and optimum distance between ion collector plate and cathode disc are studied. The stable discharge current and maximum output ion beam current have been obtained using grid exit aperture. It was found that the optimum distance between ion collector plate and ion exit aperture is equal to 6.25 cm. The cold cathode ion source is used to deposit aluminum coating layer on AZ31 magnesium alloy using argon ion beam current which equals 600 μA. Scanning electron microscope and X-ray diffraction techniques used for characterizing samples before and after aluminum deposition.

  13. "Fast Excitation" CID in Quadrupole Ion Trap Mass Spectrometer

    SciTech Connect

    Murrell, J.; Despeyroux, D.; Lammert, Stephen {Steve} A; Stephenson Jr, James {Jim} L; Goeringer, Doug

    2003-01-01

    Collision-induced dissociation (CID) in a quadrupole ion trap mass spectrometer is usually performed by applying a small amplitude excitation voltage at the same secular frequency as the ion of interest. Here we disclose studies examining the use of large amplitude voltage excitations (applied for short periods of time) to cause fragmentation of the ions of interest. This process has been examined using leucine enkephalin as the model compound and the motion of the ions within the ion trap simulated using ITSIM. The resulting fragmentation information obtained is identical with that observed by conventional resonance excitation CID. ''Fast excitation'' CID deposits (as determined by the intensity ratio of the a{sub 4}/b{sub 4} ion of leucine enkephalin) approximately the same amount of internal energy into an ion as conventional resonance excitation CID where the excitation signal is applied for much longer periods of time. The major difference between the two excitation techniques is the higher rate of excitation (gain in kinetic energy) between successive collisions with helium atoms with ''fast excitation'' CID as opposed to the conventional resonance excitation CID. With conventional resonance excitation CID ions fragment while the excitation voltage is still being applied whereas for ''fast excitation'' CID a higher proportion of the ions fragment in the ion cooling time following the excitation pulse. The fragmentation of the (M + 17H){sup 17+} of horse heart myoglobin is also shown to illustrate the application of ''fast excitation'' CID to proteins.

  14. Selection of Environmentally Friendly Solvents for the Extravehicular Mobility Unit Secondary Oxygen Pack Cold Trap Testing

    NASA Technical Reports Server (NTRS)

    Steele, John; Chullen, Cinda; Morenz, Jesse; Stephenson, Curtis

    2010-01-01

    Freon-113(TradeMark) has been used as a chemistry lab sampling solvent at NASA/JSC for EMU (extravehicular Mobility Unit) SOP (Secondary Oxygen Pack) oxygen testing Cold Traps utilized at the USA (United Space Alliance) Houston facility. Similar testing has occurred at the HSWL (Hamilton Sundstrand Windsor Locks) facility. A NASA Executive Order bans the procurement of all ODS (ozone depleting substances), including Freon-113 by the end of 2009. In order to comply with NASA direction, HSWL began evaluating viable solvents to replace Freon-113 . The study and testing effort to find Freon-113 replacements used for Cold Trap sampling is the subject of this paper. Test results have shown HFE-7100 (a 3M fluorinated ether) to be an adequate replacement for Freon-113 as a solvent to remove and measure the non-volatile residue collected in a Cold Trap during oxygen testing. Furthermore, S-316 (a Horiba Instruments Inc. high molecular weight, non-ODS chlorofluorocarbon) was found to be an adequate replacement for Freon-113 as a solvent to reconstitute non-volatile residue removed from a Cold Trap during oxygen testing for subsequent HC (hydrocarbon) analysis via FTIR (Fourier Transform Infrared Spectroscopy).

  15. Development and Analysis of Cold Trap for Use in Fission Surface Power-Primary Test Circuit

    NASA Technical Reports Server (NTRS)

    Wolfe, T. M.; Dervan, C. A.; Pearson, J. B.; Godfroy, T. J.

    2012-01-01

    The design and analysis of a cold trap proposed for use in the purification of circulated eutectic sodium potassium (NaK-78) loops is presented. The cold trap is designed to be incorporated into the Fission Surface Power-Primary Test Circuit (FSP-PTC), which incorporates a pumped NaK loop to simulate in-space nuclear reactor-based technology using non-nuclear test methodology as developed by the Early Flight Fission-Test Facility. The FSP-PTC provides a test circuit for the development of fission surface power technology. This system operates at temperatures that would be similar to those found in a reactor (500-800 K). By dropping the operating temperature of a specified percentage of NaK flow through a bypass containing a forced circulation cold trap, the NaK purity level can be increased by precipitating oxides from the NaK and capturing them within the cold trap. This would prevent recirculation of these oxides back through the system, which may help prevent corrosion.

  16. Mobility-Selected Ion Trapping and Enrichment Using Structures for Lossless Ion Manipulations

    DOE PAGESBeta

    Chen, Tsung-Chi; Ibrahim, Yehia M.; Webb, Ian K.; Garimella, Sandilya V. B.; Zhang, Xing; Hamid, Ahmed M.; Deng, Liulin; Karnesky, William E.; Prost, Spencer A.; Sandoval, Jeremy A.; et al

    2016-01-11

    The integration of ion mobility spectrometry (IMS) with mass spectrometry (MS) and the ability to trap ions in IMS-MS measurements is of great importance for performing reactions, accumulating ions, and increasing analytical measurement sensitivity. The development of Structures for Lossless Ion Manipulations (SLIM) offers the potential for ion manipulations in a more reliable and cost-effective manner, while opening opportunities for much more complex sequences of manipulations. Here, we demonstrate an ion separation and trapping module and a method based upon SLIM that consists of a linear mobility ion drift region, a switch/tee and a trapping region that allows the isolationmore » and accumulation of mobility-separated species. The operation and optimization of the SLIM switch/tee and trap are described and demonstrated for the enrichment of the low abundance ions. Lastly, we observed a linear increase in ion intensity with the number of trapping/accumulation events using the SLIM trap, illustrating its potential for enhancing the sensitivity of low abundance or targeted species.« less

  17. A System for Trapping Barium Ions in a Microfabricated Surface Trap

    NASA Astrophysics Data System (ADS)

    Zhou, Zichao; Wright, John; Graham, Richard; Sakrejda, Tomasz; Chen, Bing; Blinov, Boris; Musiqc Team

    2013-05-01

    We have developed a vacuum chamber and control system for rapid testing and development of microfabricated surface traps. Barium ions have been successfully cooled and trapped in this system. The dark lifetime of a single 138Ba + in this trap is up to 30s. And we can shuttle of ions at rate of 8 cm/s between different potential zones. Our system uses a modular design and is based on an in-vacuum PCB with integrated filters. Control of up to 96 DC electrodes is achieved with an update rate of 20 kHz using a custom FPGA based control system. Collection of fluorescence light over a numerical aperture of 0.28 has been achieved. This work is supported by IAPRA.

  18. Photoionizing Trapped Highly Charged Ions with Synchrotron Radiation

    SciTech Connect

    Crespo, J R; Simon, M; Beilmann, C; Rudolph, J; Steinbruegge, R; Eberle, S; Schwarz, M; Baumann, T; Schmitt, B; Brunner, F; Ginzel, R; Klawitter, R; Kubicek, K; Epp, S; Mokler, P; Maeckel, V; Ullrich, J; Brown, G V; Graf, A; Leutenegger, M; Beiersdorfer, P; Behar, E; Follath, R; Reichardt, G; Schwarzkopf, O

    2011-09-12

    Photoabsorption by highly charged ions plays an essential role in astrophysical plasmas. Diagnostics of photoionized plasmas surrounding binary systems rely heavily on precise identification of absorption lines and on the knowledge of their cross sections and widths. Novel experiments using an electron beam ion trap, FLASH EBIT, in combination with monochromatic synchrotron radiation allow us to investigate ions in charge states hitherto out of reach. Trapped ions can be prepared in any charge state at target densities sufficient to measure absorption cross sections below 0.1 Mb. The results benchmark state-of-the-art predictions of the transitions wavelengths, widths, and absolute cross sections. Recent high resolution results on Fe{sup 14+}, Fe{sup 15+}, and Ar{sup 12+} at photon energies up to 1 keV are presented.

  19. Diviner Lunar Radiometer observations of cold traps in the Moon's south polar region.

    PubMed

    Paige, David A; Siegler, Matthew A; Zhang, Jo Ann; Hayne, Paul O; Foote, Emily J; Bennett, Kristen A; Vasavada, Ashwin R; Greenhagen, Benjamin T; Schofield, John T; McCleese, Daniel J; Foote, Marc C; DeJong, Eric; Bills, Bruce G; Hartford, Wayne; Murray, Bruce C; Allen, Carlton C; Snook, Kelly; Soderblom, Laurence A; Calcutt, Simon; Taylor, Fredric W; Bowles, Neil E; Bandfield, Joshua L; Elphic, Richard; Ghent, Rebecca; Glotch, Timothy D; Wyatt, Michael B; Lucey, Paul G

    2010-10-22

    Diviner Lunar Radiometer Experiment surface-temperature maps reveal the existence of widespread surface and near-surface cryogenic regions that extend beyond the boundaries of persistent shadow. The Lunar Crater Observation and Sensing Satellite (LCROSS) struck one of the coldest of these regions, where subsurface temperatures are estimated to be 38 kelvin. Large areas of the lunar polar regions are currently cold enough to cold-trap water ice as well as a range of both more volatile and less volatile species. The diverse mixture of water and high-volatility compounds detected in the LCROSS ejecta plume is strong evidence for the impact delivery and cold-trapping of volatiles derived from primitive outer solar system bodies. PMID:20966246

  20. Diviner lunar radiometer observations of cold traps in the moon's south polar region

    USGS Publications Warehouse

    Paige, D.A.; Siegler, M.A.; Zhang, J.A.; Hayne, P.O.; Foote, E.J.; Bennett, K.A.; Vasavada, A.R.; Greenhagen, B.T.; Schofield, J.T.; McCleese, D.J.; Foote, M.C.; DeJong, E.; Bills, B.G.; Hartford, W.; Murray, B.C.; Allen, C.C.; Snook, K.; Soderblom, L.A.; Calcutt, S.; Taylor, F.W.; Bowles, N.E.; Bandfield, J.L.; Elphic, R.; Ghent, R.; Glotch, T.D.; Wyatt, M.B.; Lucey, P.G.

    2010-01-01

    Diviner Lunar Radiometer Experiment surface-temperature maps reveal the existence of widespread surface and near-surface cryogenic regions that extend beyond the boundaries of persistent shadow. The Lunar Crater Observation and Sensing Satellite (LCROSS) struck one of the coldest of these regions, where subsurface temperatures are estimated to be 38 kelvin. Large areas of the lunar polar regions are currently cold enough to cold-trap water ice as well as a range of both more volatile and less volatile species. The diverse mixture of water and high-volatility compounds detected in the LCROSS ejecta plume is strong evidence for the impact delivery and cold-trapping of volatiles derived from primitive outer solar system bodies.

  1. Characterization of protonated phospholipids as fragile ions in quadrupole ion trap mass spectrometry

    PubMed Central

    Garrett, Timothy J.; Merves, Matthew; Yost, Richard A.

    2011-01-01

    Some ions exhibit “ion fragility” in quadrupole ion trap mass spectrometry (QIT-MS) during mass analysis with resonance ejection. In many cases, different ions generated from the same compound exhibit different degrees of ion fragility, with some ions (e.g., the [M+H]+ ion) stable and other ions (e.g., the [M+Na]+ ion) fragile. The ion fragility for quadrupole ion trap (QIT) mass spectrometry (MS) for protonated and sodiated ions of three phospholipids, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine, PC (16:0/16:0), 1,2-dipalmitoyl-sn-glycero-3-phophoethanolamine, PE (16:0/16:0), and N-palmitoyl-D-erythro-sphingosylphosphorylcholine, SM (d18:1/16:0), was determined using three previously developed experiments: 1) the peak width using a slow scan speed, 2) the width of the isolation window for efficient isolation, and 3) the energy required for collision-induced dissociation. In addition, ion fragility studies were designed and performed to explore a correlation between ion fragility in QIT mass analysis and ion fragility during transport between the ion source and the ion trap. These experiments were: 1) evaluating the amount of thermal-induced dissociation as a function of heated capillary temperature, and 2) determining the extent of fragmentation occurring with increasing tube lens voltage. All phospholipid species studied exhibited greater ion fragility as protonated species in ion trap mass analysis than as sodiated species. In addition, the protonated species of both SM (d18:0/16:0) and PC (16:0/16:0) exhibited greater tendencies to fragment at higher heated capillary temperatures and high tube lens voltages, whereas the PE (16:0/16:0) ions did not appear to exhibit fragility during ion transport. PMID:22247650

  2. Field-free junctions for surface electrode ion traps

    NASA Astrophysics Data System (ADS)

    Jordens, Robert; Schmied, R.; Blain, M. G.; Leibfried, D.; Wineland, D.

    2015-05-01

    Intersections between transport guides in a network of RF ion traps are a key ingredient to many implementations of scalable quantum information processing with trapped ions. Several junction architectures demonstrated so far are limited by varying radial secular frequencies, a reduced trap depth, or a non-vanishing RF field along the transport channel. We report on the design and progress in implementing a configurable microfabricated surface electrode Y-junction that employs switchable RF electrodes. An essentially RF-field-free pseudopotential guide between any two legs of the junction can be established by applying RF potential to a suitable pair of electrodes. The transport channel's height above the electrodes, its depth and radial curvature are constant to within 15%. Supported by IARPA, Sandia, NSA, ONR, and the NIST Quantum Information Program.

  3. Dual-Ion-Trap Frequency Standards With Overlapping Cycles

    NASA Technical Reports Server (NTRS)

    Dick, G. John; Prestage, John D.

    1992-01-01

    Proposed scheme for enhancing performances of atomic frequency-standard apparatuses calls for two or more ion traps per apparatus interrogated in alternation by radio-frequency pulses. Provides nearly constant feedback gain, thereby providing nearly constant corrections for fluctuations in frequency of local oscillator. Degradation of performance by fluctuations in local oscillators reduced.

  4. Bidirectional Quantum Secure Direct Communication in Trapped Ion Systems

    NASA Astrophysics Data System (ADS)

    Cui, Yeqin; Gao, Jianguo

    2016-03-01

    We propose a feasible scheme for implementing quantum secure direct communication in trapped ion systems. According to the results measured by the sender, the receiver can obtain different secret messages in a deterministic way. Our scheme is insensitive to both the initial vibrational state and heating. The probability of the success in our scheme is 1.0.

  5. Quantum Communication in the Ion-Trapped System

    NASA Astrophysics Data System (ADS)

    Xu, Xiong

    2016-03-01

    A theoretical scheme of quantum communication is proposed in the context of ion-trapped systems. According to the results, the receiver can obtain different secret messages in a deterministic way. Our scheme is insensitive to both the initial vibrational state and heating. The probability of the success in our scheme is 1.0.

  6. Quantum Simulation of Quantum Field Theories in Trapped Ions

    SciTech Connect

    Casanova, J.; Lamata, L.; Egusquiza, I. L.; Gerritsma, R.; Roos, C. F.; Garcia-Ripoll, J. J.; Solano, E.

    2011-12-23

    We propose the quantum simulation of fermion and antifermion field modes interacting via a bosonic field mode, and present a possible implementation with two trapped ions. This quantum platform allows for the scalable add up of bosonic and fermionic modes, and represents an avenue towards quantum simulations of quantum field theories in perturbative and nonperturbative regimes.

  7. Criteria for ultrastable operation of the trapped ion frequency standard

    NASA Technical Reports Server (NTRS)

    Tjoelker, R. L.; Prestage, J. D.; Maleki, L.

    1992-01-01

    The leading systematic perturbations to the Jet Propulsion Laboratory's (JPL's) mercury trapped ion frequency standard are characterized under present operating conditions. Sensitivity of the standard to environmental variations is measured, and the required regulation of key components to obtain a stability of 10(exp -16) is identified.

  8. Electron Cooling of Ions and Antiprotons in Traps

    SciTech Connect

    Zwicknagel, Guenter

    2006-03-20

    For a theoretical description of electron cooling of ions or antiprotons in traps we have investigated the energy loss and cooling force in a strongly magnetized electron plasma employing both perturbation approaches and more complete numerical simulations. Some characteristic features for cooling under conditions prevailing in Penning traps are presented. One particular feature is, that the energy loss in strongly magnetized electrons, which tend to move along the field lines like beads on a wire, strongly depends on the sign of the interaction. The energy loss can be significantly larger for antiprotons than for protons. Special attention is paid to the cooling of highly charged ions, here bare Uranium, in HITRAP. The time evolution of the energy distribution of the trapped ions is studied within a simplified model which takes into account the related heating of the electrons. The feedback of this heating on the energy loss results in an intricate dependency of the cooling times on the density of the electrons and the ratio of the number of ions to the number of electrons in the trap. From this analysis we find that cooling times less than about a second are feasible for electron cooling of bare Uranium in HITRAP.

  9. Differentially pumped dual linear quadrupole ion trap mass spectrometer

    SciTech Connect

    Owen, Benjamin C.; Kenttamaa, Hilkka I.

    2015-10-20

    The present disclosure provides a new tandem mass spectrometer and methods of using the same for analyzing charged particles. The differentially pumped dual linear quadrupole ion trap mass spectrometer of the present disclose includes a combination of two linear quadrupole (LQIT) mass spectrometers with differentially pumped vacuum chambers.

  10. Quantum energy teleportation with trapped ions

    SciTech Connect

    Hotta, Masahiro

    2009-10-15

    We analyze a protocol of quantum energy teleportation that transports energy from the left edge of a linear ion crystal to the right edge by local operations and classical communication at a speed considerably greater than the speed of a phonon in the crystal. A probe qubit is strongly coupled with phonon fluctuation in the ground state for a short time and it is projectively measured in order to obtain information about this phonon fluctuation. During the measurement process, phonons are excited by the time-dependent measurement interaction and the energy of the excited phonons must be infused from outside the system. The obtained information is transferred to the right edge of the crystal through a classical channel. Even though the phonons excited at the left edge do not arrive at the right edge at the same time as when the information arrives at the right edge, we are able to soon extract energy from the ions at the right edge by using the transferred information. Because the intermediate ions of the crystal are not excited during the execution of the protocol, energy is transmitted in the energy-transfer channel without heat generation.

  11. Fluorescence imaging for visualization of the ion cloud in a quadrupole ion trap mass spectrometer.

    PubMed

    Talbot, Francis O; Sciuto, Stephen V; Jockusch, Rebecca A

    2013-12-01

    Laser-induced fluorescence is used to visualize populations of gaseous ions stored in a quadrupole ion trap (QIT) mass spectrometer. Presented images include the first fluorescence image of molecular ions collected under conditions typically used in mass spectrometry experiments. Under these "normal" mass spectrometry conditions, the radial (r) and axial (z) full-width at half maxima (FWHM) of the detected ion cloud are 615 and 214 μm, respectively, corresponding to ~6% of r0 and ~3% of z0 for the QIT used. The effects on the shape and size of the ion cloud caused by varying the pressure of helium bath gas, the number of trapped ions, and the Mathieu parameter q z are visualized and discussed. When a "tickle voltage" is applied to the exit end-cap electrode, as is done in collisionally activated dissociation, a significant elongation in the axial, but not the radial, dimension of the ion cloud is apparent. Finally, using spectroscopically distinguishable fluorophores of two different m/z values, images are presented that illustrate stratification of the ion cloud; ions of lower m/z (higher qz) are located in the center of the trapping region, effectively excluding higher m/z (lower qz) ions, which form a surrounding layer. Fluorescence images such as those presented here provide a useful reference for better understanding the collective behavior of ions in radio frequency (rf) trapping devices and how phenomena such as collisions and space-charge affect ion distribution. PMID:24092629

  12. Fluorescence Imaging for Visualization of the Ion Cloud in a Quadrupole Ion Trap Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Talbot, Francis O.; Sciuto, Stephen V.; Jockusch, Rebecca A.

    2013-12-01

    Laser-induced fluorescence is used to visualize populations of gaseous ions stored in a quadrupole ion trap (QIT) mass spectrometer. Presented images include the first fluorescence image of molecular ions collected under conditions typically used in mass spectrometry experiments. Under these "normal" mass spectrometry conditions, the radial ( r) and axial ( z) full-width at half maxima (FWHM) of the detected ion cloud are 615 and 214 μm, respectively, corresponding to ~6 % of r 0 and ~3 % of z 0 for the QIT used. The effects on the shape and size of the ion cloud caused by varying the pressure of helium bath gas, the number of trapped ions, and the Mathieu parameter q z are visualized and discussed. When a "tickle voltage" is applied to the exit end-cap electrode, as is done in collisionally activated dissociation, a significant elongation in the axial, but not the radial, dimension of the ion cloud is apparent. Finally, using spectroscopically distinguishable fluorophores of two different m/ z values, images are presented that illustrate stratification of the ion cloud; ions of lower m/ z (higher q z ) are located in the center of the trapping region, effectively excluding higher m/ z (lower q z ) ions, which form a surrounding layer. Fluorescence images such as those presented here provide a useful reference for better understanding the collective behavior of ions in radio frequency (rf) trapping devices and how phenomena such as collisions and space-charge affect ion distribution.

  13. A new ion mobility-linear ion trap instrument for complex mixture analysis.

    PubMed

    Donohoe, Gregory C; Maleki, Hossein; Arndt, James R; Khakinejad, Mahdiar; Yi, Jinghai; McBride, Carroll; Nurkiewicz, Timothy R; Valentine, Stephen J

    2014-08-19

    A new instrument that couples a low-pressure drift tube with a linear ion trap mass spectrometer is demonstrated for complex mixture analysis. The combination of the low-pressure separation with the ion trapping capabilities provides several benefits for complex mixture analysis. These include high sensitivity, unique ion fragmentation capabilities, and high reproducibility. Even though the gas-phase separation and the mass measurement steps are each conducted in an ion filtering mode, detection limits for mobility-selected peptide ions are in the tens of attomole range. In addition to ion separation, the low-pressure drift tube can be used as an ion fragmentation cell yielding mobility-resolved fragment ions that can be subsequently analyzed by multistage tandem mass spectrometry (MS(n)) methods in the ion trap. Because of the ion trap configuration, these methods can be comprised of any number (limited by ion signal) of collision-induced dissociation (CID) and electron transfer dissociation (ETD) processes. The high reproducibility of the gas-phase separation allows for comparison of two-dimensional ion mobility spectrometry (IMS)-MS data sets in a pixel-by-pixel fashion without the need for data set alignment. These advantages are presented in model analyses representing mixtures encountered in proteomics and metabolomics experiments. PMID:25068446

  14. EXPERIMENTAL STUDY OF ION INJECTION INTO AN EXTENDED TRAP OF THE BNL EBIS.

    SciTech Connect

    PIKIN,A.; ALESSI,J.; BEEBE,E.; KPONOU,A.; PRELEC,K.

    2001-09-02

    Experiments on the BNL EBIS Test Stand (EBTS) with the ion trap extending beyond the edges of the superconducting solenoid had the main goal to study ion trap operation with a trap length exceeding that of the normal EBTS trap. Preliminary results indicate that the ion trap with length 107 cm is stable and controllable in the same fashion as our normal 70 cm trap with a multiampere electron beam. EBTS operation with ion trap 145 cm long and with electron current up to 3 A in earlier experiments also was stable and yielded more ions than from the basic ''short'' trap. These results increased our confidence in operation of the proposed RHIC in a stable mode and in the correctness of linear scaling of ion intensity with the length of the ion trap.

  15. Coulomb crystal mass spectrometry in a digital ion trap

    NASA Astrophysics Data System (ADS)

    Deb, Nabanita; Pollum, Laura L.; Smith, Alexander D.; Keller, Matthias; Rennick, Christopher J.; Heazlewood, Brianna R.; Softley, Timothy P.

    2015-03-01

    We present a mass spectrometric technique for identifying the masses and relative abundances of Coulomb-crystallized ions held in a linear Paul trap. A digital radio-frequency wave form is employed to generate the trapping potential, as this can be cleanly switched off, and static dipolar fields are subsequently applied to the trap electrodes for ion ejection. Close to 100% detection efficiency is demonstrated for Ca+ and CaF+ ions from bicomponent Ca+-CaF+ Coulomb crystals prepared by the reaction of Ca+ with CH3F . A quantitative linear relationship is observed between ion number and the corresponding integrated time-of-flight (TOF) peak, independent of the ionic species. The technique is applicable to a diverse range of multicomponent Coulomb crystals—demonstrated here for Ca+-NH 3+ -NH 4+ and Ca+-CaOH +-CaOD + crystals—and will facilitate the measurement of ion-molecule reaction rates and branching ratios in complicated reaction systems.

  16. Klein tunneling and Dirac potentials in trapped ions

    SciTech Connect

    Casanova, J.; Garcia-Ripoll, J. J.; Gerritsma, R.; Roos, C. F.; Solano, E.

    2010-08-15

    We propose the quantum simulation of the Dirac equation with potentials, allowing the study of relativistic scattering and Klein tunneling. This quantum relativistic effect permits a positive-energy Dirac particle to propagate through a repulsive potential via the population transfer to negative-energy components. We show how to engineer scalar, pseudoscalar, and other potentials in the 1+1 Dirac equation by manipulating two trapped ions. The Dirac spinor is represented by the internal states of one ion, while its position and momentum are described by those of a collective motional mode. The second ion is used to build the desired potentials with high spatial resolution.

  17. A high-performance Hg(+) trapped ion frequency standard

    NASA Technical Reports Server (NTRS)

    Prestage, J. D.; Tjoelker, R. L.; Dick, G. J.; Maleki, L.

    1992-01-01

    A high-performance frequency standard based on (199)Hg(+) ions confined in a hybrid radio frequency (RF)/dc linear ion trap is demonstrated. This trap permits storage of large numbers of ions with reduced susceptibility to the second-order Doppler effect caused by the RF confining fields. A 160-mHz-wide atomic resonance line for the 40.5-GHz clock transition is used to steer the output of a 5-mHz crystal oscillator to obtain a stability of 2 x 10(exp -15) for 24,000-second averaging times. Measurements with a 37-mHz line width for the Hg(+) clock transition demonstrate that the inherent stability for this frequency standard is better than 1 x 10(exp -15) at 10,000-second averaging times.

  18. Ultra-stable Hg(+) trapped ion frequency standard

    NASA Technical Reports Server (NTRS)

    Prestage, J. D.; Tjoelker, R. L.; Dick, G. J.; Maleki, L.

    1992-01-01

    We report the development of a fieldable frequency standard based on Hg-199(+) ions confined in a hybrid r.f./dc linear ion trap. This trap permits storage of large numbers of ions with reduced susceptibility to the second-order Doppler effect caused by the r.f. confining fields. A 160 mHz wide atomic resonance line for the 40.5 GHz clock transition is used to steer the output of a 5 MHz crystal oscillator to obtain a stability of 2 x 10 exp -15 for 24,000 s averaging times. For longer averaging intervals, measurements are limited by instabilities in available hydrogen maser frequency standards. Measurements with 37 mHz linewidth for the Hg(+) clock transition demonstrate that the inherent stability for this frequency standard is at least as good as 1 x 10 exp -15.

  19. Scalable digital hardware for a trapped ion quantum computer

    NASA Astrophysics Data System (ADS)

    Mount, Emily; Gaultney, Daniel; Vrijsen, Geert; Adams, Michael; Baek, So-Young; Hudek, Kai; Isabella, Louis; Crain, Stephen; van Rynbach, Andre; Maunz, Peter; Kim, Jungsang

    2015-09-01

    Many of the challenges of scaling quantum computer hardware lie at the interface between the qubits and the classical control signals used to manipulate them. Modular ion trap quantum computer architectures address scalability by constructing individual quantum processors interconnected via a network of quantum communication channels. Successful operation of such quantum hardware requires a fully programmable classical control system capable of frequency stabilizing the continuous wave lasers necessary for loading, cooling, initialization, and detection of the ion qubits, stabilizing the optical frequency combs used to drive logic gate operations on the ion qubits, providing a large number of analog voltage sources to drive the trap electrodes, and a scheme for maintaining phase coherence among all the controllers that manipulate the qubits. In this work, we describe scalable solutions to these hardware development challenges.

  20. β-delayed neutron spectroscopy using trapped radioactive ions.

    PubMed

    Yee, R M; Scielzo, N D; Bertone, P F; Buchinger, F; Caldwell, S; Clark, J A; Deibel, C M; Fallis, J; Greene, J P; Gulick, S; Lascar, D; Levand, A F; Li, G; Norman, E B; Pedretti, M; Savard, G; Segel, R E; Sharma, K S; Sternberg, M G; Van Schelt, J; Zabransky, B J

    2013-03-01

    A novel technique for β-delayed neutron spectroscopy has been demonstrated using trapped ions. The neutron-energy spectrum is reconstructed by measuring the time of flight of the nuclear recoil following neutron emission, thereby avoiding all the challenges associated with neutron detection, such as backgrounds from scattered neutrons and γ rays and complicated detector-response functions. (137)I(+) ions delivered from a (252)Cf source were confined in a linear Paul trap surrounded by radiation detectors, and the β-delayed neutron-energy spectrum and branching ratio were determined by detecting the β(-) and recoil ions in coincidence. Systematic effects were explored by determining the branching ratio three ways. Improvements to achieve higher detection efficiency, better energy resolution, and a lower neutron-energy threshold are proposed. PMID:23496704

  1. Single trapped ion as a time-dependent harmonic oscillator

    SciTech Connect

    Menicucci, Nicolas C.; Milburn, G. J.

    2007-11-15

    We show how a single trapped ion may be used to test a variety of important physical models realized as time-dependent harmonic oscillators. The ion itself functions as its own motional detector through laser-induced electronic transitions. Alsing et al., [Phys. Rev. Lett. 94, 220401 (2005)] proposed that an exponentially decaying trap frequency could be used to simulate (thermal) Gibbons-Hawking radiation in an expanding universe, but the Hamiltonian used was incorrect. We apply our general solution to this experimental proposal, correcting the result for a single ion and showing that while the actual spectrum is different from the Gibbons-Hawking case, it nevertheless shares an important experimental signature with this result.

  2. Investigation of cold collision in a two isotope magneto-optical trap for Krypton atoms

    NASA Astrophysics Data System (ADS)

    Singh, S.; Tiwari, V. B.; Kale, Y. B.; Mishra, S. R.; Rawat, H. S.

    2015-09-01

    We report simultaneous cooling and trapping of metastable 84Kr (84Kr*) and metastable 86Kr (86Kr*) atoms by overlapping the cooling laser beams for these different isotopes in the same region of a magneto-optical trap (MOT). Approximately 2 × 105 atoms of each isotope were trapped in this two isotope-MOT (TIMOT). We have investigated the heteronuclear collision trap loss rates for each isotope due to the presence of cold atoms of other isotope using the TIMOT loading curves. The two body heteronuclear loss rate coefficient {β }{84Kr*-{}86Kr*} (i.e. for the loss of 84Kr* due to presence of 86Kr*) and the reciprocal loss rate coefficient {β }{86Kr*-{}84Kr*} (i.e. for the loss of 86Kr* due to presence of 84Kr*) are measured to be (8.7 ± 0.8) × 10-10 cm3 s-1 and (8.8 ± 0.8) × 10-10 cm3 s-1 respectively for laser beam intensity values of 21 mW cm-2 (for cooling of 84Kr*) and 64 mW cm-2 (for cooling of 86Kr*). The dependence of heteronuclear cold collision loss rate on cooling laser beams intensity has also been studied and compared with homonuclear cold collision loss rate.

  3. Ion Trap Array-Based Systems And Methods For Chemical Analysis

    DOEpatents

    Whitten, William B [Oak Ridge, TN; Ramsey, J Michael [Knoxville, TN

    2005-08-23

    An ion trap-based system for chemical analysis includes an ion trap array. The ion trap array includes a plurality of ion traps arranged in a 2-dimensional array for initially confining ions. Each of the ion traps comprise a central electrode having an aperture, a first and second insulator each having an aperture sandwiching the central electrode, and first and second end cap electrodes each having an aperture sandwiching the first and second insulator. A structure for simultaneously directing a plurality of different species of ions out from the ion traps is provided. A spectrometer including a detector receives and identifies the ions. The trap array can be used with spectrometers including time-of-flight mass spectrometers and ion mobility spectrometers.

  4. Novel method for unambiguous ion identification in mixed ion beams extracted from an electron beam ion trap

    SciTech Connect

    Meissl, W.; Simon, M. C.; Crespo Lopez-Urrutia, J. R.; Tawara, H.; Ullrich, J.; Winter, HP.; Aumayr, F.

    2006-09-15

    A novel technique to identify small fluxes of mixed highly charged ion beams extracted from an electron beam ion trap is presented and practically demonstrated. The method exploits projectile charge state dependent potential emission of electrons as induced by ion impact on a metal surface to separate ions with identical or very similar mass-to-charge ratio.

  5. Improving Ion Mobility Measurement Sensitivity by Utilizing Helium in an Ion Funnel-Trap

    SciTech Connect

    Ibrahim, Yehia M.; Garimella, Venkata BS; Tolmachev, Aleksey V.; Baker, Erin Shammel; Smith, Richard D.

    2014-05-01

    Ion mobility instruments that utilize nitrogen as buffer gas are often preceded by an ion trap and accumulation region that also uses nitrogen, and for different inert gases no significant effects upon performance are expected for IMS of larger ions. However, we have observed significantly improved performance for an ion funnel trap upon adding helium; the signal intensities for higher m/z species were improved by more than an order of magnitude compared to using pure nitrogen. The effect of helium upon IMS resolving power was also studied by introducing a He/N2 gas mixture into the drift cell, and in some cases a slight improvement was observed compared to pure N2. The improvement in signal can be largely attributed to faster and more efficient ion ejection into the drift tube from the ion funnel trap.

  6. Frequency-scanning MALDI linear ion trap mass spectrometer for large biomolecular ion detection.

    PubMed

    Lu, I-Chung; Lin, Jung Lee; Lai, Szu-Hsueh; Chen, Chung-Hsuan

    2011-11-01

    This study presents the first report on the development of a matrix-assisted laser desorption ionization (MALDI) linear ion trap mass spectrometer for large biomolecular ion detection by frequency scan. We designed, installed, and tested this radio frequency (RF) scan linear ion trap mass spectrometer and its associated electronics to dramatically extend the mass region to be detected. The RF circuit can be adjusted from 300 to 10 kHz with a set of operation amplifiers. To trap the ions produced by MALDI, a high pressure of helium buffer gas was employed to quench extra kinetic energy of the heavy ions produced by MALDI. The successful detection of the singly charged secretory immunoglobulin A ions indicates that the detectable mass-to-charge ratio (m/z) of this system can reach ~385 000 or beyond. PMID:21932813

  7. Shortcuts to adiabaticity for an ion in a rotating radially-tight trap

    NASA Astrophysics Data System (ADS)

    Palmero, M.; Wang, Shuo; Guéry-Odelin-Shin Li, D., Jr.; Muga, J. G.

    2016-04-01

    We engineer the fast rotation of an effectively one-dimensional ion trap for a predetermined rotation angle and time, avoiding the final excitation of the trapped ion. Different schemes are proposed with different speed limits that depend on the control capabilities. We also make use of trap rotations to create squeezed states without manipulating the trap frequencies.

  8. MEMS-based arrays of micro ion traps for quantum simulation scaling.

    SciTech Connect

    Berkeland, Dana J.; Blain, Matthew Glenn; Jokiel, Bernhard, Jr.

    2006-11-01

    In this late-start Tier I Seniors Council sponsored LDRD, we have designed, simulated, microfabricated, packaged, and tested ion traps to extend the current quantum simulation capabilities of macro-ion traps to tens of ions in one and two dimensions in monolithically microfabricated micrometer-scaled MEMS-based ion traps. Such traps are being microfabricated and packaged at Sandia's MESA facility in a unique tungsten MEMS process that has already made arrays of millions of micron-sized cylindrical ion traps for mass spectroscopy applications. We define and discuss the motivation for quantum simulation using the trapping of ions, show the results of efforts in designing, simulating, and microfabricating W based MEMS ion traps at Sandia's MESA facility, and describe is some detail our development of a custom based ion trap chip packaging technology that enables the implementation of these devices in quantum physics experiments.

  9. Synthetic gauge fields for vibrational excitations of trapped ions.

    PubMed

    Bermudez, Alejandro; Schaetz, Tobias; Porras, Diego

    2011-10-01

    The vibrations of a collection of ions in a microtrap array can be described in terms of tunneling phonons. We show that the vibrational couplings may be tailored by using a gradient of the trap frequencies together with a periodic driving of the trapping potentials. These ingredients allow us to induce effective gauge fields on the vibrational excitations, such that phonons mimic the behavior of charged particles in a magnetic field. In particular, microtrap arrays are well suited to realize a quantum simulator of the famous Aharonov-Bohm effect and observe the paradigmatic edge states typical from quantum-Hall samples and topological insulators. PMID:22107274

  10. Double well potentials and quantum phase transitions in ion traps.

    PubMed

    Retzker, A; Thompson, R C; Segal, D M; Plenio, M B

    2008-12-31

    We demonstrate that the radial degree of freedom of strings of trapped ions in the quantum regime may be prepared and controlled accurately through the variation of the external trapping potential while at the same time its properties are measurable with high spatial and temporal resolution. This provides a new testbed giving access to static and dynamical properties of the physics of quantum-many-body systems and quantum phase transitions that are hard to simulate on classical computers. Furthermore, it allows for the creation of double well potentials with experimentally accessible tunneling rates, with applications in testing the foundations of quantum physics and precision sensing. PMID:19437628

  11. Excitation and photo-ionization of ultra-cold potassium atoms in the AC-driven magneto optical trap (AC-MOT)

    NASA Astrophysics Data System (ADS)

    Agomuo, John; Murray, Andrew; Harvey, Matthew

    2014-03-01

    The operation of a new cold atom trap (the AC-MOT) and its application in photoionization experiments is described. Ionization of cold K atoms in the AC-MOT is discussed, the ionization proceeding in a stepwise fashion using a combination of infra-red radiation with that from a blue diode laser. A significant limitation of magneto optical trapping (MOT) techniques has been the requirement to eliminate the magnetic fields prior to the interaction occurring. To address this, the AC-MOT was invented in Manchester. This is a pulsed trap, so that the magnetic fields are completely eliminated prior to the electron interaction. Low energy electrons can then be extracted from laser photoionization. In this work, the potassium is cooled to ~0.25mK. Photoionization proceeds by a stepwise route, atoms excited by the trapping laser at ~766nm being ionized by radiation at ~448nm. Both fluorescence from the atoms and the ion yield are used to determine details of the interaction. These techniques are being studied since it then is possible to create cold electron bunches of high coherence. A detailed description of the AC-MOT, its operation and application will be presented. A new cold electron source being built in Manchester will also be discussed. I wish to acknowledge the financial support from Tertiary Education Trust Fund Nigeria and Nigerian Defence Academy Kaduna.

  12. Generation of a Cold Atom Beam from a Pyramidal Magneto-Optical Trap

    NASA Technical Reports Server (NTRS)

    Kohel, J.; Thompson, R. J.; Seidel, D. J.; Klipstein, W. M.; Maleki, L.; Bliss, J.; Libbrecht, K. G.

    2000-01-01

    Techniques to generate cold atom beams are of great interest in a variety of applications, from atomic frequency standards and atom optics to experimental studies of Bose-Einstein condensation. Cold atom beams have been produced by slowing thermal atomic beams using the Zeeman-slowing technique or chirped lasers, or using laser-cooling techniques to extract a slow atomic beam from the background gas in a low-pressure vapor cell. These laser-cooling techniques include "atomic funnels" or two-dimensional magneto-optical traps, as well as a variation of the conventional vapor cell magneto-optical trap called the "low-velocity intense source" (LVIS). Variations of the LVIS have been realized with unique trap geometries such as conical or pyramidal mirror traps. The present work implements a simple and robust design based on the pyramidal trap geometry and allows use of a single large diameter (

  13. Magnetostatic traps for charged and neutral particles

    NASA Astrophysics Data System (ADS)

    Gomer, V.; Harms, O.; Haubrich, D.; Schadwinkel, H.; Strauch, F.; Ueberholz, B.; Aus der Wiesche, S.; Meschede, D.

    1997-08-01

    We have constructed magnetostatic traps from permanent magnets for trapping charged and neutral atoms. Two storage experiments are presented: a compact Penning trap for light ions and magnetic trapping of single neutral atoms. The dynamics of cold neutral atoms and their loss mechanisms in a quadrupole magnetostatic trap are discussed.

  14. Microsecond pulsed hydrogen/deuterium exchange of electrosprayed ubiquitin ions stored in a linear ion trap.

    PubMed

    Rajabi, Khadijeh

    2015-02-01

    A pulse of D2O vapour on the order of microseconds is allowed to react with the +6 to +9 charge states of ubiquitin confined in a linear ion trap (LIT). Two envelopes of peaks are detected for the ions of ubiquitin, corresponding to the ions that exchange more quickly and more slowly. The deuterium uptake of the protonated sites on ubiquitin ions accounts for the ion population with the fast exchange. The hydrogen/deuterium exchange (HDX) kinetics of ubiquitin ions trapped in the LIT for 200 ms showed comparable structural transitions to those trapped for 300 ms. When ions are trapped for longer, i.e. up to 2000 ms, mainly the slow exchanging ion population is detected. In all experiments the +7 ions exchange the most, suggesting a short distance between the surface protonated sites and nearby charged sites, and concomitantly high accessibility of surface protonated sites towards D2O. The +6 ions are more compact than the +7 ions but have one fewer protonated site, therefore fewer surface availabilities for D2O attack. The data suggest that the +6 ions keep most of their solution-phase contacts intact while the hydrophobic core is slightly interrupted in the +7 ions, possibly due to the exposure of charged His68 that is normally buried in the hydrophobic pocket. The +8 and +9 ions have more protonated sites but are less compact than the +7 ions because of Coulombic repulsion, resulting in a larger distance between the protonated sites and the basic sites. The data indicate that the HDX mechanism of ions with the slower exchange corresponding to the second envelope of peaks is primarily governed via a relay mechanism. The results suggest that the pulsed HDX MS method is sampling a population of ubiquitin ions with a similar backbone fold to the solution. PMID:25553956

  15. Reply to 'Comment on 'Quantum time-of-flight distribution for cold trapped atoms''

    SciTech Connect

    Ali, Md. Manirul; Home, Dipankar; Pan, Alok K.; Majumdar, A. S.

    2008-02-15

    In their comment Gomes et al. [Phys. Rev. A 77, 026101 (2008)] have questioned the possibility of empirically testable differences existing between the semiclassical time of flight distribution for cold trapped atoms and a quantum distribution discussed by us recently [Ali et al., Phys. Rev. A 75, 042110 (2007).]. We argue that their criticism is based on a semiclassical treatment having restricted applicability for a particular trapping potential. Their claim does not preclude, in general, the possibility of differences between the semiclassical calculations and fully quantum results for the arrival time distribution of freely falling atoms.

  16. Addressing single trapped ions for Rydberg quantum logic

    NASA Astrophysics Data System (ADS)

    Bachor, P.; Feldker, T.; Walz, J.; Schmidt-Kaler, F.

    2016-08-01

    We demonstrate the excitation of ions to the Rydberg state 22F by vacuum ultraviolet radiation at a wavelength of 123 nm combined with the coherent manipulation of the optical qubit transition in {}40{{Ca}}+. With a tightly focused beam at 729 nm wavelength we coherently excite a single ion from a linear string into the metastable 3{D}5/2 state before a VUV pulse excites it to the Rydberg state. In combination with ion shuttling in the trap, we extend this approach to the addressed excitation of multiple ions. The coherent initialization as well as the addressed Rydberg excitation are key prerequisites for more complex applications of Rydberg ions in quantum simulation or quantum information processing.

  17. Cryogenic Linear Ion Trap for Large-Scale Quantum Simulations

    NASA Astrophysics Data System (ADS)

    Pagano, Guido; Hess, Paul; Kaplan, Harvey; Birckelbaw, Eric; Hernanez, Micah; Lee, Aaron; Smith, Jake; Zhang, Jiehang; Monroe, Christopher

    2016-05-01

    Ions confined in RF Paul traps are a useful tool for quantum simulation of long-range spin-spin interaction models. As the system size increases, classical simulation methods become incapable of modeling the exponentially growing Hilbert space, necessitating quantum simulation for precise predictions. Current experiments are limited to less than 30 qubits due to collisions with background gas that regularly destroys the ion crystal. We present progress toward the construction of a cryogenic ion trap apparatus, which uses differential cryopumping to reduce vacuum pressure to a level where collisions do not occur. This should allow robust trapping of about 100 ions/qubits in a single chain with long lifetimes. Such a long chain will provide a platform to investigate simultaneously cooling of various vibrational modes and will enable quantum simulations that outperform their classical counterpart. Our apparatus will provide a powerful test-bed to investigate a large variety of Hamiltonians, including spin 1 and spin 1/2 systems with Ising or XY interactions. This work is supported by the ARO Atomic Physics Program, the AFOSR MURI on Quantum Measurement and Verification, the IC Fellowship Program and the NSF Physics Frontier Center at JQI.

  18. Cryogenic Linear Ion Trap for Large-Scale Quantum Simulations

    NASA Astrophysics Data System (ADS)

    Kaplan, H. B.; Hess, P. W.; Pagano, G.; Birckelbaw, E. J.; Hernandez, M.; Lee, A. C.; Smith, J.; Zhang, J.; Monroe, C.

    2016-05-01

    Ions confined in RF Paul traps are a useful tool for quantum simulation of long-range spin-spin interaction models. As the system size increases, classical simulation methods become incapable of modeling the exponentially growing Hilbert space, necessitating quantum simulation for precise predictions. Current experiments are limited to less than 30 qubits due to collisions with background gas that regularly destroys the ion crystal. We present progress toward the construction of a cryogenic ion trap apparatus, which uses differential cryopumping to reduce vacuum pressure to a level where collisions do not occur. This should allow robust trapping of about 100 ions/qubits in a single chain with long lifetimes. Such a long chain will provide a platform to investigate simultaneously cooling of various vibrational modes and will enable quantum simulations that outperform their classical counterpart. Our apparatus will provide a powerful test-bed to investigate a large variety of Hamiltonians, including spin 1 and spin 1/2 systems with Ising or XY interactions. This work is supported by the ARO Atomic Physics Program, the AFOSR MURI on Quantum Measurement and Verification, and the NSF Physics Frontier Center at JQI.

  19. Ultrasensitive detection of force and displacement using trapped ions.

    PubMed

    Biercuk, Michael J; Uys, Hermann; Britton, Joe W; VanDevender, Aaron P; Bollinger, John J

    2010-09-01

    The ability to detect extremely small forces and nanoscale displacements is vital for disciplines such as precision spin-resonance imaging, microscopy, and tests of fundamental physical phenomena. Current force-detection sensitivity limits have surpassed 1 aN Hz(-1/2) (refs 6,7) through coupling of nanomechanical resonators to a variety of physical readout systems. Here, we demonstrate that crystals of trapped atomic ions behave as nanoscale mechanical oscillators and may form the core of exquisitely sensitive force and displacement detectors. We report the detection of forces with a sensitivity of 390 +/- 150 yN Hz(-1/2), which is more than three orders of magnitude better than existing reports using nanofabricated devices(7), and discriminate ion displacements of approximately 18 nm. Our technique is based on the excitation of tunable normal motional modes in an ion trap and detection through phase-coherent Doppler velocimetry, and should ultimately allow force detection with a sensitivity better than 1 yN Hz(-1/2) (ref. 16). Trapped-ion-based sensors could enable scientists to explore new regimes in materials science where augmented force, field and displacement sensitivity may be traded against reduced spatial resolution. PMID:20729835

  20. Ultrasensitive detection of force and displacement using trapped ions

    NASA Astrophysics Data System (ADS)

    Biercuk, Michael J.; Uys, Hermann; Britton, Joe W.; Vandevender, Aaron P.; Bollinger, John J.

    2010-09-01

    The ability to detect extremely small forces and nanoscale displacements is vital for disciplines such as precision spin-resonance imaging, microscopy, and tests of fundamental physical phenomena. Current force-detection sensitivity limits have surpassed 1 aN Hz-1/2 (refs 6,7) through coupling of nanomechanical resonators to a variety of physical readout systems. Here, we demonstrate that crystals of trapped atomic ions behave as nanoscale mechanical oscillators and may form the core of exquisitely sensitive force and displacement detectors. We report the detection of forces with a sensitivity of 390 +/- 150 yN Hz-1/2, which is more than three orders of magnitude better than existing reports using nanofabricated devices7, and discriminate ion displacements of ~18 nm. Our technique is based on the excitation of tunable normal motional modes in an ion trap and detection through phase-coherent Doppler velocimetry, and should ultimately allow force detection with a sensitivity better than 1 yN Hz-1/2 (ref. 16). Trapped-ion-based sensors could enable scientists to explore new regimes in materials science where augmented force, field and displacement sensitivity may be traded against reduced spatial resolution.

  1. Miniaturized Sources and Traps for Spectroscopy of Multicharged Ions

    NASA Astrophysics Data System (ADS)

    Tan, Joseph; Guise, Nicholas

    2013-05-01

    Penning traps made extremely compact (<150 cc) with rare-earth (NdFeB) magnets have been used recently to isolate highly charged ions (HCI) for spectroscopy. For example, radiative lifetimes of metastable states are measured by observing the visible fluorescence emitted by isolated Ar XIV (441 nm, 2p 2P3/2 --> 2p 2P1/2) and Kr XVIII (637 nm, 3d 2D3/2 --> 3d 2D1/2) . These measurements use HCIs extracted from an electron beam ion trap (EBIT) at NIST. For planned experiments, a new apparatus is being developed which will incorporate a ``mini-EBIT'' source using similar permanent-magnet structures. It combines a mini-EBIT and a compact Penning trap to facilitate production of multicharged ions including bare nuclei with nuclear charge in the range Z =1 to Z =10, in a cryogen-free setup with multiple ports for laser and atomic beam access to the isolated HCI. One goal is to produce one-electron ions in Rydberg states with transitions accessible to an optical frequency comb. Such engineered atomic systems are sought to enable tests of theory that could illuminate the proton radius puzzle. J.N. Tan, S.M. Brewer, and N.D. Guise, Rev. Sci. Instrum. 83, 023103 (2012).

  2. Copper ion-exchanged channel waveguides optimization for optical trapping.

    PubMed

    Reshak, A H; Khor, K N; Shahimin, M M; Murad, S A Z

    2013-08-01

    Optical trapping of particles has become a powerful non-mechanical and non-destructive technique for precise particle positioning. The manipulation of particles in the evanescent field of a channel waveguide potentially allows for sorting and trapping of several particles and cells simultaneously. Channel waveguide designs can be further optimized to increase evanescent field prior to the fabrication process. This is crucial in order to make sure that the surface intensity is sufficient for optical trapping. Simulation configurations are explained in detail with specific simulation flow. Discussion on parameters optimization; physical geometry, optical polarization and wavelength is included in this paper. The effect of physical, optical parameters and beam spot size on evanescent field has been thoroughly discussed. These studies will continue toward the development of a novel copper ion-exchanged waveguide as a method of particle sorting, with biological cell propulsion studies presently underway. PMID:23726859

  3. Projection of diffraction patterns for use in cold-neutral-atom trapping

    SciTech Connect

    Gillen-Christandl, Katharina; Gillen, Glen D.

    2010-12-15

    Scalar diffraction theory is combined with beam-propagation techniques to investigate the projection of near-field diffraction patterns to spatial locations away from the aperture for use in optically trapping cold neutral alkali-metal atoms. Calculations show that intensity distributions with localized bright and dark spots usually found within a millimeter of the diffracting aperture can be projected to a region free from optical components such as a cloud of cold atoms within a vacuum chamber. Calculations also predict that the critical properties of the optical dipole atom traps are not only maintained for the projected intensity patterns but also can be manipulated and improved by adjustment of the optical components outside the vacuum chamber.

  4. Dipole Field Effects on Ion Ejections from a Paul Ion Trap

    NASA Technical Reports Server (NTRS)

    MacAskill, J. A.; Chutjian, A.

    2011-01-01

    Attempts at improving the quality of mass spectra obtained from a Paul trap mass spectrometer prompted an investigation of the effects of additional fields to supplement the primary rf quadrupole trapping field. Reported here are the results of the first in a series of tests that focuses on the application of a single dipole field to augment the trapping and subsequent ejections of ions stored within a Paul trap. Measurements are presented for a fixed quadrupole frequency with varying dipole frequencies. The presence of the dipole field during the quadrupole trapping phase causes ion ejections of single m/z species at discrete dipole frequencies. During the mass analysis phase, the varying dipole frequency produces a complex set of resonant structures that impact ejection time (mass range), as well as mass spectral peak intensity and width

  5. Method of cold welding using ion beam technology

    NASA Technical Reports Server (NTRS)

    Sater, B. L. (Inventor)

    1981-01-01

    A method for cold welding metal joints is described. In order to remove the contamination layer on the surface of the metal, an ion beam generator is used in a vacuum environment. A gas, such as xenon or argon, is ionized and accelerated toward the metal surface. The beam of gas effectively sputters away the surface oxides and contamination layer so that clean underlying metal is exposed in the area to be welded. The use of this method allows cold welding with minimal deformation. Both similar and dissimilar metals can be cold welded with this method.

  6. Quantum-enhanced deliberation of learning agents using trapped ions

    NASA Astrophysics Data System (ADS)

    Dunjko, V.; Friis, N.; Briegel, H. J.

    2015-02-01

    A scheme that successfully employs quantum mechanics in the design of autonomous learning agents has recently been reported in the context of the projective simulation (PS) model for artificial intelligence. In that approach, the key feature of a PS agent, a specific type of memory which is explored via random walks, was shown to be amenable to quantization, allowing for a speed-up. In this work we propose an implementation of such classical and quantum agents in systems of trapped ions. We employ a generic construction by which the classical agents are ‘upgraded’ to their quantum counterparts by a nested process of adding coherent control, and we outline how this construction can be realized in ion traps. Our results provide a flexible modular architecture for the design of PS agents. Furthermore, we present numerical simulations of simple PS agents which analyze the robustness of our proposal under certain noise models.

  7. Electromagnetic two-dimensional analysis of trapped-ion eigenmodes

    SciTech Connect

    Kim, D.; Rewoldt, G.

    1984-11-01

    A two-dimensional electromagnetic analysis of the trapped-ion instability for the tokamak case with ..beta.. not equal to 0 has been made, based on previous work in the electrostatic limit. The quasineutrality condition and the component of Ampere's law along the equilibrium magnetic field are solved for the perturbed electrostatic potential and the component of the perturbed vector potential along the equilibrium magnetic field. The general integro-differential equations are converted into a matrix eigenvalue-eigenfunction problem by expanding in cubic B-spline finite elements in the minor radius and in Fourier harmonics in the poloidal angle. A model MHD equilibrium with circular, concentric magnetic surfaces and large aspect ratio is used which is consistent with our assemption that B << 1. The effect on the trapped-ion mode of including these electromagnetic extensions to the calculation is considered, and the temperature (and ..beta..) scaling of the mode frequency is shown and discussed.

  8. A New Trapped Ion Clock Based on Hg-201(+)

    NASA Technical Reports Server (NTRS)

    Taghavi-Larigani, S.; Burt, E. A.; Lea, S. N.; Prestage, J. D.; Tjoelker, R. L.

    2009-01-01

    There are two stable odd isotopes of mercury with singly ionized hyperfine structure suitable for a microwave clock: Hg-199(+) and Hg-201(+). Virtually all trapped mercury ion clocks to date have used the 199 isotope. We have begun to investigate the viability of a trapped ion clock based on Hg-201(+). We have measured the unperturbed frequency of the (S-2)(sub 1/2) F = 1, m(sub F) = 0 to (S-2)(sub 1/2) F = 2, m(sub F) = 0 clock transition to be 29.9543658211(2) GHz. In this paper we describe initial measurements with Hg-201(+) and new applications to clocks and fundamental physics.

  9. Entanglement and Quantum Information Processing with Trapped Ions*

    NASA Astrophysics Data System (ADS)

    Chiaverini, John

    2004-05-01

    Atomic ions confined in radio frequency traps, cooled and addressed with laser pulses, constitute a scalable system for bringing about and exploring quantum entanglement and information processing. Along with relatively high entangling-gate and single-qubit-rotation fidelities, long coherence times enable the execution of some basic quantum algorithms and communication protocols. At NIST we use a multi-zone trap in which entanglement can be distributed over the zones through the spatial separation and combination of several entangled ion qubits, each of which can be separately measured. Current experiments include superdense coding, quantum teleportation, entanglement-enhanced quantum state detection, and entangled state spectroscopy. These experiments and those from other groups will be summarized. *This work was supported by ARDA/NSA and NIST, and done in collaboration with T. Schaetz, M. Barrett, D. Leibfried, J. Britton, W. Itano, J. Jost, C. Langer, R. Ozeri, T. Rosenband, and D. J. Wineland.

  10. On the measurement the neutron lifetime using ultra-cold neutrons in a vacuum quadrupole trap

    SciTech Connect

    Bowman, J. D.; Penttila, S. I.

    2004-01-01

    We present a conceptual design for an experiment to measure the neutron lifetime ({approx}882 s) with an accuracy of 10{sup -4}. The lifetime will be measured by observing the decay rate of a sample of UCNs confined in vacuum in a magnetic trap. The UCN collaboration at LANL has developed a prototype ultra-cold neutron UCN source that is expected to produce a bottled UCN density of more than 100 UCN/cm{sup 3}. The availability of such an intense source makes it possible to approach the measurement of the neutron lifetime in a new way. We argue below that it is possible to measure the neutron lifetime to 10{sup -4} in a vacuum magnetic trap. The measurement involves no new technology beyond the expected UCN density. If even higher densities are available, the experiment can be made better and/or less expensive. We present the design and methodology for the measurement. The slow loss of neutrons that have stable orbits, but are not energetically trapped would produce a systematic error in the measurement. We discuss a new approach, chaotic cleaning, to the elimination of quasi-neutrons from the trap by breaking the rotational symmetry of the quadrupole trap. The neutron orbits take on a chaotic character and mode mixing causes the neutrons on the quasi-bound orbits to leave the trap.

  11. Coherent manipulation of cold cesium atoms in a nanofiber-based two-color dipole trap

    NASA Astrophysics Data System (ADS)

    Sayrin, Clement

    2013-05-01

    We have recently demonstrated a new experimental platform for trapping and optically interfacing laser-cooled cesium atoms. The scheme uses a two-color evanescent field surrounding an optical nanofiber to localize the atoms in a one-dimensional optical lattice 200 nm above the nanofiber surface. In order to use this fiber-coupled ensemble of trapped atoms for applications in the context of quantum communication and quantum information processing, non-classical states of the atomic spins have to be prepared and should live long enough to allow one to apply successive quantum operations. However, the close proximity of the trapped atoms to the nanofiber surface and the strong polarization gradients of nanofiber-guided light fields are potentially important sources of decoherence. In this talk, I will present our latest experimental results on characterizing the coherence properties of atomic spins in our nanofiber-based trap. Using a microwave field to drive the cesium clock transition, we determine inhomogeneous and homogeneous dephasing times by Ramsey and spin echo techniques, respectively, and identify the sources of the measured decoherence. Our results constitute the first measurement of the coherence properties of atoms trapped in the vicinity of a nanofiber and represent a fundamental step towards establishing nanofiber-based traps for cold atoms as a building block in quantum networks.

  12. Simulating quantum Brownian motion with single trapped ions

    SciTech Connect

    Maniscalco, S.; Piilo, J.; Intravaia, F.; Petruccione, F.; Messina, A.

    2004-05-01

    We study the open system dynamics of a harmonic oscillator coupled with an artificially engineered reservoir. We single out the reservoir and system variables governing the passage between Lindblad-type and non-Lindblad-type dynamics of the reduced system's oscillator. We demonstrate the existence of conditions under which virtual exchanges of energy between system and reservoir take place. We propose to use a single trapped ion coupled to engineered reservoirs in order to simulate quantum Brownian motion.

  13. Spectroscopy of Argon Excited in an Electron Beam Ion Trap

    SciTech Connect

    Trabert, E

    2005-04-18

    Argon is one of the gases best investigated and most widely used in plasma discharge devices for a multitude of applications that range from wavelength reference standards to controlled fusion experiments. Reviewing atomic physics and spectroscopic problems in various ionization stages of Ar, the past use and future options of employing an electron beam ion trap (EBIT) for better and more complete Ar data in the x-ray, EUV and visible spectral ranges are discussed.

  14. Measurement of femtosecond atomic lifetimes using ion traps

    NASA Astrophysics Data System (ADS)

    Träbert, Elmar

    2014-01-01

    Two types of experiment are described that both employ an electron beam ion trap for the production of highly charged ion species with the aim of then measuring atomic level lifetimes in the femtosecond range. In one experiment (done by Beiersdorfer et al. some time ago), the lifetime measurement depends on the associated line broadening. In a recent string of experiments at Linac Coherent Light Source Stanford, the HI-LIGHT collaboration employed pump-probe excitation using the FEL as a short-pulse X-ray laser.

  15. Quantum simulation of the dynamical Casimir effect with trapped ions

    NASA Astrophysics Data System (ADS)

    Trautmann, N.; Hauke, P.

    2016-04-01

    Quantum vacuum fluctuations are a direct manifestation of Heisenberg’s uncertainty principle. The dynamical Casimir effect (DCE) allows for the observation of these vacuum fluctuations by turning them into real, observable photons. However, the observation of this effect in a cavity QED experiment would require the rapid variation of the length of a cavity with relativistic velocities, a daunting challenge. Here, we propose a quantum simulation of the DCE using an ion chain confined in a segmented ion trap. We derive a discrete model that enables us to map the dynamics of the multimode radiation field inside a variable-length cavity to radial phonons of the ion crystal. We perform a numerical study comparing the ion-chain quantum simulation under realistic experimental parameters to an ideal Fabry–Perot cavity, demonstrating the viability of the mapping. The proposed quantum simulator, therefore, allows for probing the photon (respectively phonon) production caused by the DCE on the single photon level.

  16. Development of a quadrupole ion trap mass spectrometer

    NASA Astrophysics Data System (ADS)

    Hebert, Joseph Ellis

    Because of its potential to be made portable the quadrupole ion trap (QPIT) is a prime candidate for specialized applications such as atmospheric studies, other field measurements, or measurements anywhere a laboratory instrument would be prohibitively inconvenient. To utilize the QPIT in such ways it is necessary to design and construct custom built instruments. A QPIT mass spectrometer was constructed as the foundation for such future development. Two ionization schemes were employed. Direct electron bombardment was used for in situ ion production, and UV photoionization was used to produce ions external to the trap. Calibration measurements determined that the system performed as theory dictated. It was also demonstrated that the system was capable of sampling the atmosphere and detecting the presence of an atmospheric contaminant. Finally, DC bias foils were invented as a novel approach to mass isolation in the trap. The use of DC bias foils was demonstrated to be an exceptionally easy and inexpensive method of controlling the contents of the QPIT.

  17. A new trapped ion atomic clock based on 201Hg+.

    PubMed

    Burt, Eric A; Taghavi-Larigani, Shervin; Tjoelker, Robert L

    2010-03-01

    High-resolution spectroscopy has been performed on the ground-state hyperfine transitions in trapped (201)Hg+ ions as part of a program to investigate the viability of (201)Hg+ for clock applications. Part of the spectroscopy work was directed at magnetic-field-sensitive hyperfine lines with delta m(F) = 0, which allow accurate Doppler-free measurement of the magnetic field experienced by the trapped ions. Although it is possible to measure Doppler-free magnetic-field-sensitive transitions in the commonly used clock isotope, (199)Hg+, it is more difficult. In this paper, we discuss how this (199)Hg+ feature may be exploited to produce a more stable clock or one requiring less magnetic shielding in environments with magnetic field fluctuations far in excess of what is normally found in the laboratory. We have also determined that in discharge-lamp-based trapped mercury ion clocks, the optical pumping time for (201)Hg+ is about 3 times shorter than that of (199)Hg+ This can be used to reduce dead time in the interrogation cycle for these types of clocks, thereby reducing the impact of local oscillator noise aliasing effects. PMID:20211781

  18. Atmospheric H2O2 measurement: comparison of cold trap method with impinger bubbling method

    NASA Technical Reports Server (NTRS)

    Sakugawa, H.; Kaplan, I. R.

    1987-01-01

    Collection of atmospheric H2O2 was performed by a cold trap method using dry ice-acetone as the refrigerant. The air was drawn by a pump into a glass gas trap immersed in the dry ice-acetone slush in a dewar flask at a flow rate of 2.5 l min-1 for approximately 2 h. Collection efficiency was > 99% and negligible interferences by O3, SO2 or organic matter with the collected H2O2 in the trap were observed. This method was compared with the air impinger bubbling method which has been previously described (Kok et al., 1978a, b, Envir. Sci. Technol. 12, 1072-1080). The measured total peroxide (H2O2 + organic peroxide) values in a series of aim samples collected by the impinger bubbling method (0.06-3.7 ppb) were always higher than those obtained by the cold trap method (0.02-1.2 ppb). Laboratory experiments suggest that the difference in values between the two methods probably results from the aqueous phase generation of H2O2 and organic peroxide in the impinger solution by a reaction of atmospheric O3 with olefinic and aromatic compounds. If these O3-organic compound reactions which occur in the impinger also occur in aqueous droplets in the atmosphere, the process could be very important for aqueous phase generation of H2O2 in clouds and rainwater.

  19. Atmospheric H 2O 2 measurement: Comparison of cold trap method with impinger bubbling method

    NASA Astrophysics Data System (ADS)

    Sakugawa, Hiroshi; Kaplan, Isaac R.

    Collection of atmospheric H 2O 2 was performed by a cold trap method using dry ice-acetone as the refrigerant. The air was drawn by a pump into a glass gas trap immersed in the dry ice-acetone slush in a dewar flask at a flow rate of 2.5ℓ -1 for ~ 2 h. Collection efficiency was > 99% and negligible interferences by O 3, SO 2 or organic matter with the collected H 2O 2 in the trap were observed. This method was compared with the air impinger bubbling method which has been previously described (Kok et al., 1978a, b, Envir, Sci. Technol.12, 1072-1080). The measured total peroxide (H 2O 2 + organic peroxide) values in a series of air samples collected by the impinger bubbling method (0.06-3.7 ppb) were always higher than those obtained by the cold trap method (0.02-1.2 ppb). Laboratory experiments suggest that the difference in values between the two methods probably results from the aqueous phase generation of H 2O 2 and organic peroxide in the impinger solution by a reaction of atmospheric O 3 with olefinic and aromatic compounds. If these O 3-organic compound reactions which occur in the impinger also occur in aqueous droplets in the atmosphere, the process could be very important for aqueous phase generation of H 2O 2 in clouds and rainwater.

  20. Atmospheric H2O2 measurement: comparison of cold trap method with impinger bubbling method.

    PubMed

    Sakugawa, H; Kaplan, I R

    1987-01-01

    Collection of atmospheric H2O2 was performed by a cold trap method using dry ice-acetone as the refrigerant. The air was drawn by a pump into a glass gas trap immersed in the dry ice-acetone slush in a dewar flask at a flow rate of 2.5 l min-1 for approximately 2 h. Collection efficiency was > 99% and negligible interferences by O3, SO2 or organic matter with the collected H2O2 in the trap were observed. This method was compared with the air impinger bubbling method which has been previously described (Kok et al., 1978a, b, Envir. Sci. Technol. 12, 1072-1080). The measured total peroxide (H2O2 + organic peroxide) values in a series of aim samples collected by the impinger bubbling method (0.06-3.7 ppb) were always higher than those obtained by the cold trap method (0.02-1.2 ppb). Laboratory experiments suggest that the difference in values between the two methods probably results from the aqueous phase generation of H2O2 and organic peroxide in the impinger solution by a reaction of atmospheric O3 with olefinic and aromatic compounds. If these O3-organic compound reactions which occur in the impinger also occur in aqueous droplets in the atmosphere, the process could be very important for aqueous phase generation of H2O2 in clouds and rainwater. PMID:11542111

  1. MODEL SIMULATIONS OF CONTINUOUS ION INTERJECTION INTO EBIS TRAP WITH SLANTED ELECTROSTATIC MIRROR.

    SciTech Connect

    PIKIN,A.; KPONOU, A.; ALESSI, J.G.; BEEBE, E.N.; PRELEC, K.; RAPARIA, D.

    2007-08-26

    The efficiency of trapping ions in an EBIS is of primary importance for many applications requiring operations with externally produced ions: RIA breeders, ion sources, traps. At the present time, the most popular method of ion injection is pulsed injection, when short bunches of ions get trapped in a longitudinal trap while traversing the trap region. Continuous trapping is a challenge for EBIS devices because mechanisms which reduce the longitudinal ion energy per charge in a trap (cooling with residual gas, energy exchange with other ions, ionization) are not very effective, and accumulation of ions is slow. A possible approach to increase trapping efficiency is to slant the mirror at the end of the trap which is opposite to the injection end. A slanted mirror will convert longitudinal motion of ions into transverse motion, and, by reducing their longitudinal velocity, prevent these ions from escaping the trap on their way out. The trade off for the increased trapping efficiency this way is an increase in the initial transverse energy of the accumulated ions. The slanted mirror can be realized if the ends of two adjacent electrodes- drift tubes - which act as an electrostatic mirror, are machined to produce a slanted gap, rather than an upright one. Applying different voltages to these electrodes will produce a slanted mirror. The results are presented of 2D and 3D computer simulations of ion injection into a simplified model of EBIS with slanted mirror.

  2. Cold ions in the hot plasma sheet of Earth's magnetotail.

    PubMed

    Seki, Kanako; Hirahara, Masafumi; Hoshino, Masahiro; Terasawa, Toshio; Elphic, Richard C; Saito, Yoshifumi; Mukai, Toshifumi; Hayakawa, Hajime; Kojima, Hirotsugu; Matsumoto, Hiroshi

    2003-04-10

    Most visible matter in the Universe exists as plasma. How this plasma is heated, and especially how the initial non-equilibrium plasma distributions relax to thermal equilibrium (as predicted by Maxwell-Boltzman statistics), is a fundamental question in studies of astrophysical and laboratory plasmas. Astrophysical plasmas are often so tenuous that binary collisions can be ignored, and it is not clear how thermal equilibrium develops for these 'collisionless' plasmas. One example of a collisionless plasma is the Earth's plasma sheet, where thermalized hot plasma with ion temperatures of about 5 x 10(7) K has been observed. Here we report direct observations of a plasma distribution function during a solar eclipse, revealing cold ions in the Earth's plasma sheet in coexistence with thermalized hot ions. This cold component cannot be detected by plasma sensors on satellites that are positively charged in sunlight, but our observations in the Earth's shadow show that the density of the cold ions is comparable to that of hot ions. This high density is difficult to explain within existing theories, as it requires a mechanism that permits half of the source plasma to remain cold upon entry into the hot turbulent plasma sheet. PMID:12686993

  3. Computer simulation of the gap-tripole ion trap with linear injection, 3D ion accumulation, and versatile packet ejection.

    PubMed

    Salazar, Gary A; Masujima, Tsutomu

    2008-09-01

    The behavior of a completely new ion trap is shown with SIMION 7.0 simulations. The simulated trap, which was a mix of a linear and a 3D trap, was made by axially setting two ion guides with a gap between them. Each guide consisted of three rods with three symmetrically delayed radio frequency (rf) voltages (tripole). The "injected" ions were linearly contained by pulsed potentials on the entrance and exit plates. Then the three-dimensional (3D) rf field in the gap, which was created by the tripole special rod arrangement, could trap the ions when the translational energy was dampened by collisions with low-pressure nitrogen. Because the injected ions were trapped in the small gap, the trapping cycle could be repeated many times before ion ejection, so a high concentrated ion cloud could be obtained. This trapping and accumulation methodology is not possible in most conventional multipole linear traps with even number of poles. Compared with quadrupole linear trap at the same rf amplitude, tripole lost more ions due to strong charge repulsion in the ion cloud. However, tripole could catch up the ions at higher voltage. Radial and axial mass-independent ejection of the ions localized in the tripole gap was very simple, compared with conventional linear ion traps that need extra and complicated electrodes for effective axial ejection. PMID:18635376

  4. In situ plasma removal of surface contaminants from ion trap electrodes

    SciTech Connect

    Haltli, Raymond A.

    2015-05-01

    In this thesis, the construction and implementation of an in situ plasma discharge designed to remove surface contaminants from electrodes in an ion trapping experimental system is presented with results. In recent years, many advances have been made in using ion traps for quantum information processing. All of the criteria defined by DiVincenzo for using ion traps for implementing a quantum computer have been individually demonstrated, and in particular surface traps provide a scalable platform for ions. In order to be used for quantum algorithms, trapped ions need to be cooled to their motional (quantum mechanical) ground state. One of the hurdles in integrating surface ion traps for a quantum computer is minimizing electric field noise, which causes the ion to heat out of its motional ground state and which increases with smaller ion-to-electrode distances realized with surface traps. Surface contamination of trap electrodes is speculated to be the primary source of electric field noise. The main goal achieved by this work was to implement an in situ surface cleaning solution for surface electrode ion traps, which would not modify the ion trap electrode surface metal. Care was taken in applying the RF power in order to localize a plasma near the trap electrodes. A method for characterizing the energy of the plasma ions arriving at the ion trap surface is presented and results for plasma ion energies are shown. Finally, a method for quantifying the effectiveness of plasma cleaning of trap electrodes, using the surface analysis technique of X-ray photoelectron spectroscopy for measuring the amount and kind of surface contaminants, is described. A significant advantage of the trap electrode surface cleaning method presented here is the minimal changes necessary for implementation on a working ion trap experimental system.

  5. Exploring Cold Trapped Volatiles from Stationary Landers and Mobile Rovers: ESA Activities for Resource Prospecting at the Poles

    NASA Astrophysics Data System (ADS)

    Carpenter, J. D.; Fisackerly, R.; Aziz, S.; Houdou, B.

    2015-10-01

    An overview of ESA activities in the area of measuring cold trapped volatiles in-situ, including the PROSPECT package for the Russian Luna-27 mission and the development of mobile platform capabilities that could be applied to future missions.

  6. Cold Trap Dismantling and Sodium Removal at a Fast Breeder Reactor - 12327

    SciTech Connect

    Graf, A.; Petrick, H.; Stutz, U.; Hosking, P.

    2012-07-01

    The first German prototype Fast Breeder Nuclear Reactor (KNK) is currently being dismantled after being the only operating Fast Breeder-type reactor in Germany. As this reactor type used sodium as a coolant in its primary and secondary circuit, seven cold traps containing various amounts of partially activated sodium needed to be disposed of as part of the dismantling. The resulting combined difficulties of radioactive contamination and high chemical reactivity were handled by treating the cold traps differently depending on their size and the amount of sodium contained inside. Six small cold traps were processed onsite by cutting them up into small parts using a band saw under a protective atmosphere. The sodium was then converted to sodium hydroxide by using water. The remaining large cold trap could not be handled in the same way due to its dimensions (2.9 m x 1.1 m) and the declared amount of sodium inside (1,700 kg). It was therefore manually dismantled inside a large box filled with a protective atmosphere, while the resulting pieces were packaged for later burning in a special facility. The experiences gained by KNK during this process may be advantageous for future dismantling projects in similar sodium-cooled reactors worldwide. The dismantling of a prototype fast breeder reactor provides the challenge not only to dismantle radioactive materials but also to handle sodium-contaminated or sodium-containing components. The treatment of sodium requires additional equipment and installations to ensure a safe handling. Since it is not permitted to bring sodium into a repository, all sodium has to be neutralized either through a controlled reaction with water or by incinerating. The resulting components can be disposed of as normal radioactive waste with no further conditions. The handling of sodium needs skilled and experienced workers to minimize the inherent risks. And the example of the disposal of the large KNK cold trap shows the interaction with others and

  7. Integrated System Technologies for Modular Trapped Ion Quantum Information Processing

    NASA Astrophysics Data System (ADS)

    Crain, Stephen G.

    Although trapped ion technology is well-suited for quantum information science, scalability of the system remains one of the main challenges. One of the challenges associated with scaling the ion trap quantum computer is the ability to individually manipulate the increasing number of qubits. Using micro-mirrors fabricated with micro-electromechanical systems (MEMS) technology, laser beams are focused on individual ions in a linear chain and steer the focal point in two dimensions. Multiple single qubit gates are demonstrated on trapped 171Yb+ qubits and the gate performance is characterized using quantum state tomography. The system features negligible crosstalk to neighboring ions (< 3e-4), and switching speeds comparable to typical single qubit gate times (< 2 mus). In a separate experiment, photons scattered from the 171Yb+ ion are coupled into an optical fiber with 63% efficiency using a high numerical aperture lens (0.6 NA). The coupled photons are directed to superconducting nanowire single photon detectors (SNSPD), which provide a higher detector efficiency (69%) compared to traditional photomultiplier tubes (35%). The total system photon collection efficiency is increased from 2.2% to 3.4%, which allows for fast state detection of the qubit. For a detection beam intensity of 11 mW/cm 2, the average detection time is 23.7 mus with 99.885(7)% detection fidelity. The technologies demonstrated in this thesis can be integrated to form a single quantum register with all of the necessary resources to perform local gates as well as high fidelity readout and provide a photon link to other systems.

  8. Demonstration of Long Vacuum Integrity Lifetime of a Trapped-Ion Clock Package

    NASA Astrophysics Data System (ADS)

    Bandi, T.; Prestage, J.; Chung, S.; Le, T.; Yu, N.

    2016-02-01

    A compact Hg ion trap package that has been vacuum-sealed since 2005 has been demonstrated to be successfully operational. This work shows the reliability of such units in view of next-generation ground and spaceborne trapped-ion clocks. The excellent vacuum property of the trap package allowed us to study charge transfer relaxation effects between neutral Hg and trapped Hg ions.

  9. Eliminating degradation and uncovering ion-trapping dynamics in electrochromic WO3 thin films

    NASA Astrophysics Data System (ADS)

    Wen, Rui-Tao; Granqvist, Claes G.; Niklasson, Gunnar A.

    2015-10-01

    There is keen interest in the use of amorphous WO3 thin films as cathodic electrodes in transmittance-modulating electrochromic devices. However, these films suffer from ion-trapping-induced degradation of optical modulation and reversibility on extended Li+-ion exchange. Here, we demonstrate that ion-trapping-induced degradation, which is commonly believed to be irreversible, can be successfully eliminated by constant-current-driven de-trapping; that is, WO3 films can be rejuvenated and regain their initial highly reversible electrochromic performance. Pronounced ion trapping occurs when x exceeds ~0.65 in LixWO3 during ion insertion. We find two main kinds of Li+-ion-trapping site (intermediate and deep) in WO3, where the intermediate ones are most prevalent. Li+ ions can be completely removed from intermediate traps but are irreversibly bound in deep traps. Our results provide a general framework for developing and designing superior electrochromic materials and devices.

  10. Eliminating degradation and uncovering ion-trapping dynamics in electrochromic WO3 thin films

    PubMed Central

    Wen, Rui-Tao; Granqvist, Claes G.; Niklasson, Gunnar A.

    2015-01-01

    Amorphous WO3 thin films are of keen interest as cathodic electrodes in transmittance-modulating electrochromic devices. However, these films suffer from ion-trapping-induced degradation of optical modulation and reversibility upon extended Li+-ion exchange. Here, we demonstrate that ion-trapping-induced degradation, which is commonly believed to be irreversible, can be successfully eliminated by constant-current-driven de-trapping, i.e., WO3 films can be rejuvenated and regain their initial highly reversible electrochromic performance. Pronounced ion-trapping occurs when x exceeds ~0.65 in LixWO3 during ion insertion. We find two main kinds of Li+-ion trapping sites (intermediate and deep) in WO3, where the intermediate ones are most prevalent. Li+-ions can be completely removed from intermediate traps but are irreversibly bound in deep traps. Our results provide a general framework for developing and designing superior electrochromic materials and devices. PMID:26259104

  11. Theoretical Study of Dual-Direction Dipolar Excitation of Ions in Linear Ion Traps

    NASA Astrophysics Data System (ADS)

    Dang, Qiankun; Xu, Fuxing; Wang, Liang; Huang, Xiaohua; Dai, Xinhua; Fang, Xiang; Wang, Rizhi; Ding, Chuan-Fan

    2016-04-01

    The ion enhanced activation and collision-induced dissociation (CID) by simultaneous dipolar excitation of ions in the two radial directions of linear ion trap (LIT) have been recently developed and tested by experiment. In this work, its detailed properties were further studied by theoretical simulation. The effects of some experimental parameters such as the buffer gas pressure, the dipolar excitation signal phases, power amplitudes, and frequencies on the ion trajectory and energy were carefully investigated. The results show that the ion activation energy can be significantly increased by dual-direction excitation using two identical dipolar excitation signals because of the addition of an excitation dimension and the fact that the ion motion radius related to ion kinetic energy can be greater than the field radius. The effects of higher-order field components, such as dodecapole field on the performance of this method are also revealed. They mainly cause ion motion frequency shift as ion motion amplitude increases. Because of the frequency shift, there are different optimized excitation frequencies in different LITs. At the optimized frequency, ion average energy is improved significantly with relatively few ions lost. The results show that this method can be used in different kinds of LITs such as LIT with 4-fold symmetric stretch, linear quadrupole ion trap, and standard hyperbolic LIT, which can significantly increase the ion activation energy and CID efficiency, compared with the conventional method.

  12. Theoretical Study of Dual-Direction Dipolar Excitation of Ions in Linear Ion Traps.

    PubMed

    Dang, Qiankun; Xu, Fuxing; Wang, Liang; Huang, Xiaohua; Dai, Xinhua; Fang, Xiang; Wang, Rizhi; Ding, Chuan-Fan

    2016-04-01

    The ion enhanced activation and collision-induced dissociation (CID) by simultaneous dipolar excitation of ions in the two radial directions of linear ion trap (LIT) have been recently developed and tested by experiment. In this work, its detailed properties were further studied by theoretical simulation. The effects of some experimental parameters such as the buffer gas pressure, the dipolar excitation signal phases, power amplitudes, and frequencies on the ion trajectory and energy were carefully investigated. The results show that the ion activation energy can be significantly increased by dual-direction excitation using two identical dipolar excitation signals because of the addition of an excitation dimension and the fact that the ion motion radius related to ion kinetic energy can be greater than the field radius. The effects of higher-order field components, such as dodecapole field on the performance of this method are also revealed. They mainly cause ion motion frequency shift as ion motion amplitude increases. Because of the frequency shift, there are different optimized excitation frequencies in different LITs. At the optimized frequency, ion average energy is improved significantly with relatively few ions lost. The results show that this method can be used in different kinds of LITs such as LIT with 4-fold symmetric stretch, linear quadrupole ion trap, and standard hyperbolic LIT, which can significantly increase the ion activation energy and CID efficiency, compared with the conventional method. Graphical Abstract ᅟ. PMID:26810433

  13. Monitoring Trace Contaminants in Air Via Ion Trap Mass Spectrometry

    NASA Technical Reports Server (NTRS)

    Palmer, Peter T.; Karr, Dane; Pearson, Richard; Valero, Gustavo; Wong, Carla

    1995-01-01

    Recent passage of the Clean Air Act with its stricter regulation of toxic gas emissions, and the ever-growing number of applications which require faster turnaround times between sampling and analysis are two major factors which are helping to drive the development of new instrument technologies for in-situ, on-line, real-time monitoring. The ion trap, with its small size, excellent sensitivity, and tandem mass spectrometry capability is a rapidly evolving technology which is well-suited for these applications. In this paper, we describe the use of a commercial ion trap instrument for monitoring trace levels of chlorofluorocarbons (CFCs) and volatile organic compounds (VOCs) in air. A number of sample introduction devices including a direct transfer line interface, short column GC, and a cryotrapping interface are employed to achieve increasing levels of sensitivity. MS, MS/MS, and MS/MS/MS methods are compared to illustrate trade-offs between sensitivity and selectivity. Filtered Noise Field (FNF) technology is found to be an excellent means for achieving lower detection limits through selective storage of the ion(s) of interest during ionization. Figures of merit including typical sample sizes, detection limits, and response times are provided. The results indicate the potential of these techniques for atmospheric assessments, the High Speed Research Program, and advanced life support monitoring applications for NASA.

  14. Upgrade of the electron beam ion trap in Shanghai

    NASA Astrophysics Data System (ADS)

    Lu, D.; Yang, Y.; Xiao, J.; Shen, Y.; Fu, Y.; Wei, B.; Yao, K.; Hutton, R.; Zou, Y.

    2014-09-01

    Over the last few years the Shanghai electron beam ion trap (EBIT) has been successfully redesigned and rebuilt. The original machine, developed under collaboration with the Shanghai Institute of Applied Physics, first produced an electron beam in 2005. It could be tuned with electron energies between 1 and 130 keV and beam current up to 160 mA. After several years of operation, it was found that several modifications for improvements were necessary to reach the goals of better electron optics, higher photon detection, and ion injection efficiencies, and more economical running costs. The upgraded Shanghai-EBIT is made almost entirely from Ti instead of stainless steel and achieves a vacuum of less than 10-10 Torr, which helps to minimize the loss of highly changed ions through charge exchange. Meanwhile, a more compact structure and efficient cryogenic system, and excellent optical alignment have been of satisfactory. The magnetic field in the central trap region can reach up till 4.8 T with a uniformity of 2.77 × 10-4. So far the upgraded Shanghai-EBIT has been operated up to an electron energy of 151 keV and a beam current of up to 218 mA, although promotion to even higher energy is still in progress. Radiation from ions as highly charged as Xe53+, 54+ has been produced and the characterization of current density is estimated from the measured electron beam width.

  15. Laser desorption lamp ionization source for ion trap mass spectrometry.

    PubMed

    Wu, Qinghao; Zare, Richard N

    2015-01-01

    A two-step laser desorption lamp ionization source coupled to an ion trap mass spectrometer (LDLI-ITMS) has been constructed and characterized. The pulsed infrared (IR) output of an Nd:YAG laser (1064 nm) is directed to a target inside a chamber evacuated to ~15 Pa causing desorption of molecules from the target's surface. The desorbed molecules are ionized by a vacuum ultraviolet (VUV) lamp (filled with xenon, major wavelength at 148 nm). The resulting ions are stored and detected in a three-dimensional quadrupole ion trap modified from a Finnigan Mat LCQ mass spectrometer operated at a pressure of ≥ 0.004 Pa. The limit of detection for desorbed coronene molecules is 1.5 pmol, which is about two orders of magnitude more sensitive than laser desorption laser ionization mass spectrometry using a fluorine excimer laser (157 nm) as the ionization source. The mass spectrum of four standard aromatic compounds (pyrene, coronene, rubrene and 1,4,8,11,15,18,22,25-octabutoxy-29H,31H-phthalocyanine (OPC)) shows that parent ions dominate. By increasing the infrared laser power, this instrument is capable of detecting inorganic compounds. PMID:25601688

  16. Upgrade of the electron beam ion trap in Shanghai

    SciTech Connect

    Lu, D.; Yang, Y.; Xiao, J.; Shen, Y.; Fu, Y.; Wei, B.; Yao, K.; Hutton, R.; Zou, Y.

    2014-09-15

    Over the last few years the Shanghai electron beam ion trap (EBIT) has been successfully redesigned and rebuilt. The original machine, developed under collaboration with the Shanghai Institute of Applied Physics, first produced an electron beam in 2005. It could be tuned with electron energies between 1 and 130 keV and beam current up to 160 mA. After several years of operation, it was found that several modifications for improvements were necessary to reach the goals of better electron optics, higher photon detection, and ion injection efficiencies, and more economical running costs. The upgraded Shanghai-EBIT is made almost entirely from Ti instead of stainless steel and achieves a vacuum of less than 10{sup −10} Torr, which helps to minimize the loss of highly changed ions through charge exchange. Meanwhile, a more compact structure and efficient cryogenic system, and excellent optical alignment have been of satisfactory. The magnetic field in the central trap region can reach up till 4.8 T with a uniformity of 2.77 × 10{sup −4}. So far the upgraded Shanghai-EBIT has been operated up to an electron energy of 151 keV and a beam current of up to 218 mA, although promotion to even higher energy is still in progress. Radiation from ions as highly charged as Xe{sup 53+,} {sup 54+} has been produced and the characterization of current density is estimated from the measured electron beam width.

  17. Cold Ion Escape from the Martian Ionosphere

    NASA Astrophysics Data System (ADS)

    Fraenz, M.; Dubinin, E.; Wei, Y.; Woch, J. G.; Morgan, D. D.; Barabash, S. V.; Lundin, R. N.; Fedorov, A.

    2012-12-01

    It has always been challenging to observe the flux of ions with energies of less than 10eV escaping from the planetary ionospheres. We here report on new measurements of the ionospheric ion flows at Mars by the ASPERA-3 experiment on board Mars Express. We first use support from the MARSIS radar experiment for some orbits with fortunate observation geometry. Here we have observed a transterminator flow of O+ and O2+ ions with a super-sonic velocity of around 5km/s and fluxes of 0.8x10^9/cm^2s. If we assume a symmetric flux around the terminator this corresponds to an ion flow of 3.1x10^25/s half of which is expected to escape from Mars (Fraenz et al, 2010). This escape flux is significantly higher than previously observed on the tailside of Mars, we discuss possible reasons for the difference. Since 2008 the MARSIS radar does nightside local plasma density measurement which often coincide with ASPERA-3 measurements. In a new analysis of the combined nightside datasets (Fig. 1) we show that the main escape channel is along the shadow boundary on the tailside of Mars. At a distance of about 0.5 R_M the flux settles at a constant value (Fig. 2) which indicates that about half of the transterminator ionospheric flow escapes from the planet. Possible mechanism to generate this flux can be the ionospheric pressure gradient between dayside and nightside or momentum transfer from the solar wind via the induced magnetic field since the flow velocity is in the Alfvenic regime.; Median oxygen ion flux reconstructed by combining ion velocity observations of the Mars Express ASPERA-3 IMA sensor and local plasma density observations by the MARSIS radar. Each bin value is the median from observations on about 3000 orbits between May 2007 and July 2011. Horizontal axis is MSO X-axis (Sun towards the left), vertical axis is vertical distance from MSO X-axis. ; Ring median flux of cylindrical ring regions of all bins shown in previous figure. The different colors show median fluxes

  18. Pharmacological Blockade of TRPM8 Ion Channels Alters Cold and Cold Pain Responses in Mice

    PubMed Central

    McCoy, Daniel D.; McKemy, David D.

    2011-01-01

    TRPM8 (Transient Receptor Potential Melastatin-8) is a cold- and menthol-gated ion channel necessary for the detection of cold temperatures in the mammalian peripheral nervous system. Functioning TRPM8 channels are required for behavioral responses to innocuous cool, noxious cold, injury-evoked cold hypersensitivity, cooling-mediated analgesia, and thermoregulation. Because of these various roles, the ability to pharmacologically manipulate TRPM8 function to alter the excitability of cold-sensing neurons may have broad impact clinically. Here we examined a novel compound, PBMC (1-phenylethyl-4-(benzyloxy)-3-methoxybenzyl(2-aminoethyl)carbamate) which robustly and selectively inhibited TRPM8 channels in vitro with sub-nanomolar affinity, as determined by calcium microfluorimetry and electrophysiology. The actions of PBMC were selective for TRPM8, with no functional effects observed for the sensory ion channels TRPV1 and TRPA1. PBMC altered TRPM8 gating by shifting the voltage-dependence of menthol-evoked currents towards positive membrane potentials. When administered systemically to mice, PBMC treatment produced a dose-dependent hypothermia in wildtype animals while TRPM8-knockout mice remained unaffected. This hypothermic response was reduced at lower doses, whereas responses to evaporative cooling were still significantly attenuated. Lastly, systemic PBMC also diminished cold hypersensitivity in inflammatory and nerve-injury pain models, but was ineffective against oxaliplatin-induced neuropathic cold hypersensitivity, despite our findings that TRPM8 is required for the cold-related symptoms of this pathology. Thus PBMC is an attractive compound that serves as a template for the formulation of highly specific and potent TRPM8 antagonists that will have utility both in vitro and in vivo. PMID:21984952

  19. Shortcuts to Adiabaticity in Transport of a Single Trapped Ion

    NASA Astrophysics Data System (ADS)

    An, Shuoming; Lv, Dingshun; Campo, Adolfo Del; Kim, Kihwan

    2015-05-01

    We report an experimental study on shortcuts to adiabaticity in the transport of a single 171Yb+ ion trapped in a harmonic potential. In these driving schemes, the application of a force induces a nonadiabatic dynamics in which excitations are tailored so as to preserve the ion motional state in the ground state upon completion of the process. We experimentally apply the laser induced force and realize three different protocols: (1) a transitionless driving with a counterdiabatic term out of phase with the displacement force, (2) a classical protocol assisted by counterdiabatic fields in phase with the main force, (3) and an engineered transport protocol based on the Fourier transform of the trap acceleration. We experimentally compare and discuss the robustness of these protocols under given experimental limitations such as trap frequency drifts. This work was supported by the National Basic Research Program of China under Grants No. 2011CBA00300 (No. 2011CBA00301), the National Natural Science Foundation of China 11374178, and the University of Massachusetts Boston (No. P20150000029279).

  20. Ion traps, quantum computing, and the measurement problem^

    NASA Astrophysics Data System (ADS)

    Wineland, D. J.

    2006-05-01

    The basic requirements for quantum computing and quantum simulation (single- and multi-qubit gates, long memory times, etc.) have been demonstrated in separate experiments on trapped ions. Construction of a useful information processor will require synthesis of these elements and implementation of high- fidelity operations on a very large number of qubits. NIST and other groups are addressing this scaling issue by trying to fabricate multi-zone arrays of traps that would allow highly- parallel processing. As the number of qubits increases, the measurement problem in quantum mechanics becomes more glaring; with luck, trapped ion systems might be able to shed light on this fundamental issue. Recent NIST work in collaboration with D. Leibfried, J. C. Bergquist, R. B. Blakestad, J. J. Bollinger, J. Britton, J. Chiaverini, R. E. Drullinger, R. Epstein, D. Hume, W. M. Itano, J. D. Jost, J. Koelemeij, E. Knill, C. Langer, R. Ozeri, R. Reichle, T. Rosenband, P. O. Schmidt, S. Seidelin, N. Shiga, and J. Wesenberg, and supported by DTO, ONR, and NIST.

  1. Investigation of ion capture in an electron beam ion trap charge-breeder for rare isotopes

    NASA Astrophysics Data System (ADS)

    Kittimanapun, Kritsada

    Charge breeding of rare isotope ions has become an important ingredient for providing reaccelerated rare isotope beams for science. At the National Superconducting Cyclotron Laboratory (NSCL), a reaccelerator, ReA, has been built that employs an advanced Electron Beam Ion Trap (EBIT) as a charge breeder. ReA will provide rare-isotope beams with energies of a few hundred keV/u up to tens of MeV/u to enable the study of properties of rare isotopes via low energy Coulomb excitation and transfer reactions, and to investigate nuclear reactions important for nuclear astrophysics. ReA consists of an EBIT charge breeder, a charge-over-mass selector, a room temperature radio-frequency quadrupole accelerator, and a superconducting radio-frequency linear accelerator. The EBIT charge breeder features a high-current electron gun, a long trap structure, and a hybrid superconducting magnet to reach both high acceptance for injected low-charge ions as well as high-electron beam current densities for fast charge breeding. In this work, continuous ion injection and capture in the EBIT have been investigated with a dedicated Monte-Carlo simulation code and in experimental studies. The Monte-Carlo code NEBIT considers the electron-impact ionization cross sections, space charge due to the electron beam current, ion dynamics, electric field from electrodes, and magnetic field from the superconducting magnet. Experiments were performed to study the capture efficiency as a function of injected ion beam current, electron beam current, trap size, and trap potential depth. The charge state evolution of trapped ions was studied, providing information about the effective current density of the electron beam inside the EBIT. An attempt was made to measure the effective space-charge potential of the electron beam by studying the dynamics of a beam injected and reflected inside the trap.

  2. Ion-trapping and end-capping in ionic polymerizations

    SciTech Connect

    Penczek, S.

    1993-12-31

    Ion-trapping, developed in this laboratory, involves both vinyl and ring-opening polymerizations, anionic and cationic. Originally it was elaborated for cationic ring-opening polymerization and involved reaction of phosphines (mostly triphenylphosphine) with onium ions, like oxonium ions in the polymerization of cyclic ethers. The same method has more recently been used for the cationic polymerization of vinyl ethers, allowing not only to determine the total concentration of the growing species by {sup 31}P-NMR but also to study the stereochemistry of the chain end by the same method. In the anionic ring-opening polymerization diphenylchlorophosphate was applied. It reacts quantitatively with alcoholate, thiolate, and carboxylate anions. More recently diphenylchlorophosphine was successfully used to determine the concentration and structure of the chain ends in the anionic polymerization of styrene, butadiene, isoprene as well as their mixtures.

  3. Quantum Simulation of the Klein Paradox with Trapped Ions

    SciTech Connect

    Gerritsma, R.; Lanyon, B. P.; Kirchmair, G.; Zaehringer, F.; Hempel, C.; Blatt, R.; Roos, C. F.; Casanova, J.; Garcia-Ripoll, J. J.; Solano, E.

    2011-02-11

    We report on quantum simulations of relativistic scattering dynamics using trapped ions. The simulated state of a scattering particle is encoded in both the electronic and vibrational state of an ion, representing the discrete and continuous components of relativistic wave functions. Multiple laser fields and an auxiliary ion simulate the dynamics generated by the Dirac equation in the presence of a scattering potential. Measurement and reconstruction of the particle wave packet enables a frame-by-frame visualization of the scattering processes. By precisely engineering a range of external potentials we are able to simulate text book relativistic scattering experiments and study Klein tunneling in an analogue quantum simulator. We describe extensions to solve problems that are beyond current classical computing capabilities.

  4. Quantum simulation of the Klein paradox with trapped ions.

    PubMed

    Gerritsma, R; Lanyon, B P; Kirchmair, G; Zähringer, F; Hempel, C; Casanova, J; García-Ripoll, J J; Solano, E; Blatt, R; Roos, C F

    2011-02-11

    We report on quantum simulations of relativistic scattering dynamics using trapped ions. The simulated state of a scattering particle is encoded in both the electronic and vibrational state of an ion, representing the discrete and continuous components of relativistic wave functions. Multiple laser fields and an auxiliary ion simulate the dynamics generated by the Dirac equation in the presence of a scattering potential. Measurement and reconstruction of the particle wave packet enables a frame-by-frame visualization of the scattering processes. By precisely engineering a range of external potentials we are able to simulate text book relativistic scattering experiments and study Klein tunneling in an analogue quantum simulator. We describe extensions to solve problems that are beyond current classical computing capabilities. PMID:21405450

  5. Measuring parity nonconservation with a single trapped atomic ion or with trapped neutral atoms

    SciTech Connect

    Fortson, E.N.

    1993-05-01

    We have begun a measurement of atomic party nonconservation (PNC) by a new approach that utilizes the remarkable sensitivity of a single trapped atomic ion. A Ba{sup +} ion in the 6{sup 2}S{sub 1/2} ground state, trapped in an RF electric potential well and cooled to an orbit much smaller than optical wavelengths, is illuminated with intense laser light tuned to the 6S-5D electric quadrupole transition at 2.05 {mu}m. PNC interference causes a light shift of the Larmor precession frequency of order 0.3 Hz, creating a detectable rotation of the electron spin in the ground state. The accuracy may be sufficient to provide a valuable test of electroweak theory either with a single barium isotope or with a string of isotopes to cancel the uncertainties in PNC due to atomic structure. The current status of the barium ion experiment will be discussed, together with the prospects for applying the PNC light shift technique also to neutral atoms with long lived excited states, such as cooled, optically confined neutral barium.

  6. Optimization of phonon dynamics protocols in ion traps

    NASA Astrophysics Data System (ADS)

    Dutta, T.; Mukherjee, M.; Sengupta, K.

    2016-03-01

    We develop a theory to address the non equilibrium dynamics of phonons in a one-dimensional finite size trapped ion system for non linear ramp and periodic protocols. Our analysis, which is based on our earlier proposal of dynamics-induced cooling and entanglement generation between phonons in these systems when subjected to a linear ramp protocol [1], identifies the optimal protocol within the above-mentioned classes, which minimizes both the cooling and entanglement generation time. We also introduce single-/two-site addressing to achieve cooling/entanglement, which is expected to lead to simpler implementation of these protocols. Finally, we discuss the effect of noise due to the fluctuation of the intensity of the laser used to generate the trap on entanglement generation. We also discuss realistic experimental setups that may serve as test beds for our theory.

  7. CuH-ZSM-5 as hydrocarbon trap under cold start conditions.

    PubMed

    Navlani-García, M; Puértolas, B; Lozano-Castelló, D; Cazorla-Amorós, D; Navarro, M V; García, T

    2013-06-01

    Cold start tests are carried out to evaluate the performance of copper-exchanged zeolites as hydrocarbon traps under simulated gasoline car exhaust gases, paying special attention to the role of copper in the performance of these zeolites. It is concluded that the partial substitution of the protons in the parent H-ZSM-5 zeolite is highly beneficial for hydrocarbon trapping due to the formation of selective adsorption sites with specific affinity for the different exhaust components. However, it is also observed that uncontrolled exchanging process conditions could lead to the presence of CuO nanoparticles in the zeolite surface, which seem to block the pore structure of the zeolite, decreasing the hydrocarbon trap efficiency. Among all the zeolites studied, the results point out that a CuH-ZSM-5 with a partial substitution of extra-framework protons by copper cations and without any detectable surface CuO nanoparticles is the zeolite that showed the best performance under simulated cold start conditions due to both the high stability and the hydrocarbon retaining capacity of this sample during the consecutive cycles. PMID:23634959

  8. Infrared spectra of small molecular ions trapped in solid neon

    SciTech Connect

    Jacox, Marilyn E.

    2015-01-22

    The infrared spectrum of a molecular ion provides a unique signature for that species, gives information on its structure, and is amenable to remote sensing. It also serves as a comparison standard for refining ab initio calculations. Experiments in this laboratory trap molecular ions in dilute solid solution in neon at 4.2 K in sufficient concentration for observation of their infrared spectra between 450 and 4000 cm{sup !1}. Discharge-excited neon atoms produce cations by photoionization and/or Penning ionization of the parent molecule. The resulting electrons are captured by other molecules, yielding anions which provide for overall charge neutrality of the deposit. Recent observations of ions produced from C{sub 2}H{sub 4} and BF{sub 3} will be discussed. Because of their relatively large possibility of having low-lying excited electronic states, small, symmetric molecular cations are especially vulnerable to breakdown of the Born-Oppenheimer approximation. Some phenomena which can result from this breakdown will be discussed. Ion-molecule reaction rates are sufficiently high that in some systems absorptions of dimer cations and anions are also observed. When H{sub 2} is introduced into the system, the initially-formed ion may react with it. Among the species resulting from such ion-molecule reactions that have recently been studied are O{sub 4}{sup +}, NH{sub 4}{sup +}, HOCO{sup +}, and HCO{sub 2}{sup !}.

  9. Arbitrary waveform generator for quantum information processing with trapped ions

    NASA Astrophysics Data System (ADS)

    Bowler, R.; Warring, U.; Britton, J. W.; Sawyer, B. C.; Amini, J.

    2013-03-01

    Atomic ions confined in multi-electrode traps have been proposed as a basis for scalable quantum information processing. This scheme involves transporting ions between spatially distinct locations by use of time-varying electric potentials combined with laser or microwave pulses for quantum logic in specific locations. We report the development of a fast multi-channel arbitrary waveform generator for applying the time-varying electric potentials used for transport and for shaping quantum logic pulses. The generator is based on a field-programmable gate array controlled ensemble of 16-bit digital-to-analog converters with an update frequency of 50 MHz and an output range of ±10 V. The update rate of the waveform generator is much faster than relevant motional frequencies of the confined ions in our experiments, allowing diabatic control of the ion motion. Numerous pre-loaded sets of time-varying voltages can be selected with 40 ns latency conditioned on real-time signals. Here we describe the device and demonstrate some of its uses in ion-based quantum information experiments, including speed-up of ion transport and the shaping of laser and microwave pulses.

  10. Infrared spectra of small molecular ions trapped in solid neon

    NASA Astrophysics Data System (ADS)

    Jacox, Marilyn E.

    2015-01-01

    The infrared spectrum of a molecular ion provides a unique signature for that species, gives information on its structure, and is amenable to remote sensing. It also serves as a comparison standard for refining ab initio calculations. Experiments in this laboratory trap molecular ions in dilute solid solution in neon at 4.2 K in sufficient concentration for observation of their infrared spectra between 450 and 4000 cm!1. Discharge-excited neon atoms produce cations by photoionization and/or Penning ionization of the parent molecule. The resulting electrons are captured by other molecules, yielding anions which provide for overall charge neutrality of the deposit. Recent observations of ions produced from C2H4 and BF3 will be discussed. Because of their relatively large possibility of having low-lying excited electronic states, small, symmetric molecular cations are especially vulnerable to breakdown of the Born-Oppenheimer approximation. Some phenomena which can result from this breakdown will be discussed. Ion-molecule reaction rates are sufficiently high that in some systems absorptions of dimer cations and anions are also observed. When H2 is introduced into the system, the initially-formed ion may react with it. Among the species resulting from such ion-molecule reactions that have recently been studied are O4+, NH4+, HOCO+, and HCO2!.

  11. Micromotion based single-qubit addressing with trapped-ions

    NASA Astrophysics Data System (ADS)

    Akerman, Nitzan; Navon, Nir; Kotler, Shlomi; Glickman, Yinnon; Almog, Ido; Ozeri, Roee

    2013-05-01

    Individual-particle addressing is a necessary capability in many quantum information experiments. For example, characterization of multi-qubit operations with quantum process tomography (QPT). We propose and demonstrate a scheme that exploits the inhomogeneous excess micromotion in ion trap to address single-qubits in a chain of several ion-qubits, separated by only few microns. The scheme uses a laser field which is resonant with the micromotion sideband of a narrow optical quadrupole transition and acts as a dressing field with a spatially-dependent coupling along the chain. As a consequence, the level spacing of each ion, in the dressed state picture, becomes position dependent and individual ions can be spectrally separated. We have demonstrated Individual Rabi flops with 85% fidelity in a three-ion chain. For the case of only two ions, the coupling can be tailored to vanish on one of the two. This allows preparing any two-qubit product state as well as completing state tomography without direct spatially-selective imaging. We demonstrate full QPT for two-qubit Sørensen-Mølmer entangling interaction (Bell-state preparation fidelity of 98%) which has not been process-analyzed yet. Our tomography resulted process fidelity of 92%. N. Navon et al. arXiv:1210.7336 (1012).

  12. Design of blade-shaped-electrode linear ion traps with reduced anharmonic contributions

    SciTech Connect

    Deng, K.; Che, H.; Ge, Y. P.; Xu, Z. T.; Yuan, W. H.; Zhang, J.; Lu, Z. H.; Lan, Y.

    2015-09-21

    RF quadrupole linear Paul traps are versatile tools in quantum physics experiments. Linear Paul traps with blade-shaped electrodes have the advantages of larger solid angles for fluorescence collection. But with these kinds of traps, the existence of higher-order anharmonic terms of the trap potentials can cause large heating rate for the trapped ions. In this paper, we theoretically investigate the dependence of higher-order terms of trap potentials on the geometry of blade-shaped traps, and offer an optimized design. A modified blade electrodes trap is proposed to further reduce higher-order anharmonic terms while still retaining large fluorescence collection angle.

  13. Engineering 2D Ising Interactions in a Large (N>100) Ensemble of Trapped Ions

    NASA Astrophysics Data System (ADS)

    Sawyer, Brian; Britton, Joseph; Keith, Adam; Wang, Joseph; Freericks, James; Uys, Hermann; Biercuk, Michael; Bollinger, John

    2012-06-01

    Experimental progress in atomic, molecular, and optical physics has enabled exquisite control over ensembles of cold trapped ions. We have recently engineered long-range Ising interactions in a two-dimensional, 1-mK Coulomb crystal of hundreds of ^9Be^+ ions confined within a Penning trap. Interactions between the ^9Be^+ valence spins are mediated via spin-dependent optical dipole forces (ODFs) coupling to transverse motional modes of the planar crystal. A continuous range of inverse power-law spin-spin interactions from infinite (1/r^0) to dipolar (1/r^3) are accessible by varying the ODF drive frequency relative to the transverse modes. The ions naturally form a triangular lattice structure within the planar array, allowing for simulation of spin frustration using our generated antiferromagnetic couplings. We report progress toward simulating the ferromagnetic/antiferromagnetic transverse quantum Ising Hamiltonians in this large ensemble. We also report spectroscopy, thermometry, and sensitive displacement detection (˜100 pm) via entanglement of valence spin and drumhead oscillations.

  14. Cold atomic beam ion source for focused ion beam applications

    SciTech Connect

    Knuffman, B.; Steele, A. V.; McClelland, J. J.

    2013-07-28

    We report measurements and modeling of an ion source that is based on ionization of a laser-cooled atomic beam. We show a high brightness and a low energy spread, suitable for use in next-generation, high-resolution focused ion beam systems. Our measurements of total ion current as a function of ionization conditions support an analytical model that also predicts the cross-sectional current density and spatial distribution of ions created in the source. The model predicts a peak brightness of 2 × 10{sup 7} A m{sup −2} sr{sup −1} eV{sup −1} and an energy spread less than 0.34 eV. The model is also combined with Monte-Carlo simulations of the inter-ion Coulomb forces to show that the source can be operated at several picoamperes with a brightness above 1 × 10{sup 7} A m{sup −2} sr{sup −1} eV{sup −1}. We estimate that when combined with a conventional ion focusing column, an ion source with these properties could focus a 1 pA beam into a spot smaller than 1 nm. A total current greater than 5 nA was measured in a lower-brightness configuration of the ion source, demonstrating the possibility of a high current mode of operation.

  15. Ion trap mass spectrometric detection of laser desorbed ions from derivatized fused silica fibers

    SciTech Connect

    Garrett, A.W.; Earl, W.L.; Cisper, M.E.; Nogar, N.S.; Hemberger, P.H.

    1994-12-31

    Solid-phase microextraction of analytes from complex matrices using fused silica fibers has many advantages over traditional chemical sample preparation technique. Microextraction requires small sample sizes little sample preparation (providing rapid sample turnaround time), and greatly reduces the amount of chemical waste generated in sample preparation. These advantages make fused silica fibers attractive for direct sampling and detection experiments using laser desorption ion trap mass spectrometry (LITMS). The drawback is the very small area ({approximately}1 mm{sup 2}) exposed to laser irradiation, which limits the amount of material desorbed into the ion trap.

  16. Coulomb crystals in a cryogenic Paul trap for sympathetic cooling of molecular ions and highly charged ions

    NASA Astrophysics Data System (ADS)

    Windberger, A.; Schwarz, M.; Versolato, O. O.; Baumann, T.; Bekker, H.; Schmöger, L.; Hansen, A. K.; Gingell, A. D.; Klosowski, L.; Kristensen, S.; Schmidt, P. O.; Ullrich, J.; Drewsen, M.; Crespo López-Urrutia, J. R.

    2013-03-01

    Electron beam ion traps used for spectroscopy of highly charged ions (HCI) produce a deep trapping potential leading to high temperatures of the stored ions, and thus limiting the achievable spectral resolution. A novel device at the Max-Planck-Institut für Kernphysik, the Cryogenic linear Paul Trap Experiment (CryPTEx), attached to an electron beam ion trap, provides a new experimental platform to overcome these limitations. The trap assembly operates at a temperature of 4 K and offers optical access for quantum manipulation and imaging of the trapped ions. Since forbidden optical transitions in HCI do not support direct laser cooling, sympathetic cooling with Coulomb crystals of singly charged ions such as Be+ or Mg+ will be applied in order to reach the natural linewidth of optical forbidden transitions in HCI of interest. With the added advantage of long ion trapping times resulting from residual gas pressures of H2 at 4 K below 10-15 mbar, CryPTEx has been commissioned in collaboration with the Ion Trap Group in Århus using rovibrationally cooled MgH+ ions. Strong suppression of the black body radiation at the trap center, ion storage times of about 28 hours, and largely enhanced population of the rovibrational ground state were achieved.

  17. Selective interactions in trapped ions: State reconstruction and quantum logic

    NASA Astrophysics Data System (ADS)

    Solano, E.

    2005-01-01

    We propose the implementation of selective interactions of atom-motion subspaces in trapped ions. These interactions yield resonant exchange of population inside a selected subspace, leaving the others in a highly dispersive regime. Selectivity allows us to generate motional Fock (and other nonclassical) states with high purity out of a wide class of initial states, and becomes an unconventional cooling mechanism when the ground state is chosen. Individual population of number states can be distinctively measured, as well as the motional Wigner function. Furthermore, a protocol for implementing quantum logic through a suitable control of selective subspaces is presented.

  18. Cotrapping different species in ion traps using multiple radio frequencies

    NASA Astrophysics Data System (ADS)

    Trypogeorgos, Dimitris; Foot, Christopher J.

    2016-08-01

    We consider the stability of systems subjected to periodic parametric driving in the context of ions confined by oscillating electric fields. The behavior of these systems can be understood in terms of a pseudopotential approximation and resonances arising from parametric excitation. We investigate the key properties of a way of operating a linear Paul trap with two radio frequencies that simultaneously confines two species with extremely different charge-to-mass ratios. The theoretical calculations have been verified by molecular dynamics simulations and normal modes analysis.

  19. Trilinear hamiltonian with trapped ions and its applications

    NASA Astrophysics Data System (ADS)

    Ding, Shiqian; Maslennikov, Gleb; Hablutzel, Roland; Matsukevich, Dzmitry

    2016-05-01

    The model of three harmonic oscillators coupled by the trilinear Hamiltonian of the form a† bc + ab†c† can describe wide range of physical processes. We experimentally realize such interaction between three modes of motion in the system of 3 trapped Yb ions. We discuss several application of this coupling, including implementation of the quantum absorption refrigerator, simulation of the interaction between light and atoms described by a Tavis-Cummings model, simulation of the non-degenerate parametric down conversion process in the fully quantum regime and studies of a simple model of Hawking radiation.

  20. Selective control of the symmetric Dicke subspace in trapped ions

    SciTech Connect

    Lopez, C. E.; Retamal, J. C.; Solano, E.

    2007-09-15

    We propose a method of manipulating selectively the symmetric Dicke subspace in the internal degrees of freedom of N trapped ions. We show that the direct access to ionic-motional subspaces, based on a suitable tuning of motion-dependent ac Stark shifts, induces a two-level dynamics involving previously selected ionic Dicke states. In this manner, it is possible to produce, sequentially and unitarily, ionic Dicke states with increasing excitation number. Moreover, we propose a probabilistic technique to produce directly any ionic Dicke state assuming suitable initial conditions.

  1. Microfabricated Surface-Electrode Ion Trap for Scalable Quantum Information Processing

    SciTech Connect

    Seidelin, S.; Chiaverini, J.; Reichle, R.; Bollinger, J.J.; Leibfried, D.; Britton, J.; Wesenberg, J.H.; Blakestad, R.B.; Epstein, R.J.; Hume, D.B.; Itano, W.M.; Jost, J.D.; Langer, C.; Ozeri, R.; Shiga, N.; Wineland, D.J.

    2006-06-30

    Individual laser-cooled {sup 24}Mg{sup +} ions are confined in a linear Paul trap with a novel geometry where gold electrodes are located in a single plane and the ions are trapped 40 {mu}m above this plane. The relatively simple trap design and fabrication procedure are important for large-scale quantum information processing (QIP) using ions. Measured ion motional frequencies are compared to simulations. Measurements of ion recooling after cooling is temporarily suspended yield a heating rate of approximately 5 motional quanta per millisecond for a trap frequency of 2.83 MHz, sufficiently low to be useful for QIP.

  2. Trap losses induced by near-resonant Rydberg dressing of cold atomic gases

    NASA Astrophysics Data System (ADS)

    Aman, J. A.; DeSalvo, B. J.; Dunning, F. B.; Killian, T. C.; Yoshida, S.; Burgdörfer, J.

    2016-04-01

    The near-resonant dressing of cold strontium gases and Bose-Einstein condensates contained in an optical dipole trap (ODT) with the 5 s 30 s S31 Rydberg state is investigated as a function of the effective two-photon Rabi frequency, detuning, and dressing time. The measurements demonstrate that a rapid decrease in the ground-state atom population in the ODT occurs even for weak dressing and when well detuned from resonance. This decrease is attributed to Rydberg atom excitation, which can lead to direct escape from the trap and to population of very long-lived 5 s 5 p 0, 2 3P metastable states. The effects of interactions between Rydberg atoms, including those populated by blackbody radiation, are analyzed. The work has important implications when considering the use of Rydberg dressing to control the interactions between dressed ground-state atoms.

  3. Generation of a Cold Atom Beam from a Pyramidal Magneto-Optical Trap

    NASA Technical Reports Server (NTRS)

    Bliss, J. L.; Libbrecht, K. G.; Maleki, Klipstein L.

    2000-01-01

    We have built an atomic beam source utilizing a simple and robust design based on the pyramidal trap geometry of Kim et al. Our design allows use of a single large diameter (\\le20 cm) laser beam to obtain large capture rates of atoms from a background vapor. A small (about 1mm diameter) hole in the retro-optic at the apex of the pyramid provides an extraction column for the atoms. We have operated the apparatus both as a magneto-optical trap (using an auxiliary plug laser beam), and as a cold atomic beam source. The characterization of this large pyramidal beam source will be reported, including an investigation of scaling to very large (10--20cm) high power (about 1W) laser beams which should allow significant improvements in atomic beam flux.

  4. Augmenting Ion Trap Mass Spectrometers Using a Frequency Modulated Drift Tube Ion Mobility Spectrometer.

    PubMed

    Morrison, Kelsey A; Siems, William F; Clowers, Brian H

    2016-03-15

    Historically, high pressure ion mobility drift tubes have suffered from low ion duty cycles and this problem is magnified when such instrumentation is coupled with ion trap mass spectrometers. To significantly alleviate these issues, we outline the result from coupling an atmospheric pressure, dual-gate drift tube ion mobility spectrometer (IMS) to a linear ion trap mass spectrometer (LIT-MS) via modulation of the ion beam with a linear frequency chirp. The time-domain ion current, once Fourier transformed, reveals a standard ion mobility drift spectrum that corresponds to the standard mode of mobility analysis. By multiplexing the ion beam, it is possible to successfully obtain drift time spectra for an assortment of simple peptide and protein mixtures using an LIT-MS while showing improved signal intensity versus the more common signal averaging technique. Explored here are the effects of maximum injection time, solution concentration, total experiment time, and frequency swept on signal-to-noise ratios (SNRs) and resolving power. Increased inject time, concentration, and experiment time all generally led to an improvement in SNR, while a greater frequency swept increases the resolving power at the expense of SNR. Overall, chirp multiplexing of a dual-gate IMS system coupled to an LIT-MS improves ion transmission, lowers analyte detection limits, and improves spectral quality. PMID:26854901

  5. Measuring and manipulating the temperature of cold molecules trapped on a chip

    NASA Astrophysics Data System (ADS)

    Marx, S.; Adu Smith, D.; Insero, G.; Meek, S. A.; Sartakov, B. G.; Meijer, G.; Santambrogio, G.

    2015-12-01

    Following Marx et al. [Phys. Rev. Lett. 111, 243007 (2013), 10.1103/PhysRevLett.111.243007], we discuss the measurement and manipulation of the temperature of cold CO molecules in a microchip environment. In particular, we present a model to explain the observed and calculated velocity distributions. We also show that a translational temperature can be extracted directly from the measurements. Finally, we discuss the conditions needed for an effective adiabatic cooling of the molecular ensemble trapped on the microchip.

  6. Linear ion trap for second-order Doppler shift reduction in frequency standard applications

    NASA Technical Reports Server (NTRS)

    Prestage, John D.; Janik, Gary R.; Dick, G. John; Maleki, Lute

    1990-01-01

    The authors have designed and are presently testing a novel linear ion trap that permits storage of a large number of ions with reduced susceptibility to the second-order Doppler effect caused by the RF confining fields. This new trap should store about 20 times the number of ions as a conventional RF trap with no corresponding increase in second-order Doppler shift from the confining field. In addition, the sensitivity of this shift to trapping parameters, i.e., RF voltage, RF frequency, and trap size, is greatly reduced. The authors have succeeded in trapping mercury ions and xenon ions in the presence of helium buffer gas. Trap times as long as 2000 s have been measured.

  7. Digital quantum simulation of Dirac equation with a trapped ion

    NASA Astrophysics Data System (ADS)

    Shen, Yangchao; Zhang, Xiang; Zhang, Junhua; Casanova, Jorge; Lamata, Lucas; Solano, Enrique; Yung, Man-Hong; Zhang, Jingning; Kim, Kihwan; Department Of Physical Chemistry Collaboration

    2014-05-01

    Recently there has been growing interest in simulating relativistic effects in controllable physical system. We digitally simulate the Dirac equation in 3 +1 dimensions with a single trapped ion. We map four internal levels of 171Yb+ ion to the Dirac bispinor. The time evolution of the Dirac equation is implemented by trotter expansion. In the 3 +1 dimension, we can observe a helicoidal motion of a free Dirac particle which reduces to Zitterbewegung in 1 +1 dimension. This work was supported in part by the National Basic Research Program of China Grant 2011CBA00300, 2011CBA00301, the National Natural Science Foundation of China Grant 61033001, 61061130540. KK acknowledge the support from the recruitment program of global youth experts.

  8. Felion: a Cryogenic Ion Trap Apparatus for Spectroscopic Studies with Felix

    NASA Astrophysics Data System (ADS)

    Brunken, S.; Kluge, L.; Fanghanel, S.; Potapov, A.; Asvany, O.; Schlemmer, S.; Oomens, J.; Redlich, B.; Stoffels, A.

    2013-06-01

    The combination of ion trapping techniques with sensitive action spectroscopy schemes has been developed in recent years as a powerful tool to obtain spectra of gas-phase molecular ions from the UV to the (F)IR spectral regions. Here we report on the status of a specifically designed, dedicated cryogenic 22-pole ion trap apparatus (FELion), developed and built in Cologne, Germany, and intended to be installed permanently at the "Free-Electron Lasers for Infrared eXperiments" (FELIX) facility in Nijmegen, the Netherlands. This instrument will allow to record gas-phase IR and FIR spectra of mass-selected, internally cold molecular ions at temperatures in the range 4-300 K. By the use of diverse ionization methods, e.g. electron impact and electrospray ionization, a multitude of molecular ions can be generated and stored in the trap, including astrophysically relevant species ranging in size from the three-atomic H_3^+ up to large polycyclic aromatic hydrocarbon (PAH) ions, but also biomolecular ions like amino acids, peptides, or nucleobases. In combination with the powerful (F)IR radiation of the free electron lasers FELIX-1 and -2 (60-2500 cm^{-1}) and FLARE (6-100 cm^{-1}) at the FELIX facility, a variety of action spectroscopy schemes can be employed to study the ro-vibrational spectra of the stored ions, such as IR multiphoton dissociation, (F)IR/UV double resonance spectroscopy, or the method of laser induced reactions (LIR). In this talk we will give a detailed account of the experimental setup and present the first results obtained with the new apparatus. e.g., S. Schlemmer, E. Lescop, J. von Richthofen, D. Gerlich, and M. A. Smith, J. Chem. Phys. 117, 2068 (2002) J. Oomens, B. G. Sartakov, G. Meijer, and G. van Helden, Int. J. Mass Spectrom. 254, 1 (2006) T. R. Rizzo, J. A. Stearns, and O. V. Boyarkin, International Reviews in Physical Chemistry 28, 481 (2009) FLARE: Free-electron Laser for Advanced spectroscopy and high-Resolution Experiments

  9. Linear Ion Trap for the Mars Organic Molecule Analyzer

    NASA Astrophysics Data System (ADS)

    Brinckerhoff, William; Arevalo, Ricardo; Danell, Ryan; van Amerom, Friso; Pinnick, Veronica; Li, Xiang; Hovmand, Lars; Getty, Stephanie; Mahaffy, Paul; Goesmann, Fred; Steininger, Harald

    2014-05-01

    The 2018 ExoMars rover mission includes the Mars Organic Molecule Analyzer (MOMA) investigation. MOMA will examine the chemical composition of samples acquired from depths of up to two meters below the martian surface, where organics may be protected from radiative and oxidative degradation. When combined with the complement of instruments in the rover's Pasteur Payload, MOMA has the potential to reveal the presence of a wide range of organics preserved in a variety of mineralogical environments, and to begin to understand the structural character and potential origin of those compounds. MOMA includes a linear, or 2D, ion trap mass spectrometer (ITMS) that is designed to analyze molecular composition of (i) gas evolved from pyrolyzed powder samples and separated on a gas chromatograph and (ii) ions directly desorbed from solid samples at Mars ambient pressure using a pulsed laser and a fast-valve capillary ion inlet system. This "dual source" approach gives MOMA unprecedented breadth of detection over a wide range of molecular weights and volatilities. Analysis of nonvolatile, higher-molecular weight organics such as carboxylic acids and peptides even in the presence of significant perchlorate concentrations is enabled by the extremely short (~1 ns) pulses of the desorption laser. Use of the ion trap's tandem mass spectrometry mode permits selective focus on key species for isolation and controlled fragmentation, providing structural analysis capabilities. The flight-like engineering test unit (ETU) of the ITMS, now under construction, will be used to verify breadboard performance with high fidelity, while simultaneously supporting the development of analytical scripts and spectral libraries using synthetic and natural Mars analog samples guided by current results from MSL. ETU campaign data will strongly advise the specifics of the calibration applied to the MOMA flight model as well as the science operational procedures during the mission.

  10. Test measurement on ion-molecule reactions in a ringelectrode ion trap

    NASA Astrophysics Data System (ADS)

    Savic, I.; Lukic, S. R.; Guth, I.; Gerlich, D.

    2006-05-01

    Very recently a new experimental setup has been developed allowing studies of astrophysically relevant collisions between neutral atoms and small pure carbon molecules from one side and ions from the other side and first results are obtained (Savić et al., 2005). The ions are stored in a radio- frequency (rf) ring-electrode trap and during reaction time exposed to the effusive carbon beam. In this paper, one of the final tests of the experimental setup is presented.

  11. Sympathetic cooling of 171 Yb+ qubit ions on a scalable ion trap chip using Yb isotopes

    NASA Astrophysics Data System (ADS)

    Kwon, Yeong-Dae; Ahn, Jun Sik; Hong, Seokjun; Lee, Minjae; Cheon, Hongjin; Cho, Dongil ``Dan''; Kim, Taehyun

    2016-05-01

    To achieve ion trap based large-scale quantum computing devices, motional states of qubit ions must be regulated against heating from ion transportation or noise on the chip surface while leaving internal states of the ions intact. Sympathetic cooling is a natural solution for this problem, but trapping two different species of ions generally requires two sets of optical devices including separate lasers for each ion type, increasing the complexity and the cost of the setup. We tested Doppler-cooled 174 Yb+ ions to sympathetically cool 171 Yb+ qubit ions. Since these two isotopes have energy levels close to each other, the optical setup can be vastly simplified. We also verified that the tail of non-ideally focused cooling beam and the scattered light from the surface create excited state population in the 171 Yb+ qubit ions, as expected. This leads to occasional spontaneous emission events, which currently limits the coherence time of our qubit to a few seconds. We will also discuss our plans for optimizing the experiment, which may increase the coherence time by one or two orders of magnitude. This work was partially supported by ICT R&D program of MSIP/IITP. [10043464, Development of quantum repeater technology for the application to communication systems].

  12. Surface ion trap structures with excellent optical access for quantum information processing

    NASA Astrophysics Data System (ADS)

    Maunz, P.; Blain, M.; Benito, F.; Chou, C.; Clark, C.; Descour, M.; Ellis, R.; Haltli, R.; Heller, E.; Kemme, S.; Sterk, J.; Tabakov, B.; Tigges, C.; Stick, D.

    2013-05-01

    Microfabricated surface electrode ion traps are necessary for the advancement of trapped ion quantum information processing as it offers a scalable way for realizing complex trap structures capable of storing and controlling many ions. The most promising way of performing two-qubit quantum gates in a chain of trapped ions is to focus laser beams on individual ions of the chain to drive gates. However, in surface ion traps the close proximity of the ions to the surface and the size of the chips usually cannot accommodate the tightly focused laser beams necessary to address individual ions parallel to the chip surface. Here we present a surface electrode ion trap monolithically fabricated in standard silicon technology that implements a linear quadrupole trap on a bowtie shaped chip with a narrow section that is only 1.2 mm wide. Laser beams parallel to the surface can be focused down to a waist of 4 μm with enough separation from the trap chip to prevent light scattering. The trap structure incorporates two Y-junctions for reordering ions and is optimized for quantum information processing. This work was supported by the Intelligence Advanced Research Projects Activity (IARPA). Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the US Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  13. Development and Evaluation of a Variable-Temperature Quadrupole Ion Trap Mass Spectrometer

    NASA Astrophysics Data System (ADS)

    Derkits, David; Wiseman, Alex; Snead, Russell F.; Dows, Martina; Harge, Jasmine; Lamp, Jared A.; Gronert, Scott

    2016-02-01

    A new, variable-temperature mass spectrometer system is described. By applying polyimide heating tape to the end-cap electrodes of a Bruker (Bremen, Germany) Esquire ion trap, it is possible to vary the effective temperature of the system between 40 and 100°C. The modification does not impact the operation of the ion trap and the heater can be used for extended periods without degradation of the system. The accuracy of the ion trap temperatures was assessed by examining two gas-phase equilibrium processes with known thermochemistry. In each case, the variable-temperature ion trap provided data that were in good accord with literature data, indicating the effective temperature in the ion trap environment was being successfully modulated by the changes in the set-point temperatures on the end-cap electrodes. The new design offers a convenient and effective way to convert commercial ion trap mass spectrometers into variable-temperature instruments.

  14. Development and Evaluation of a Variable-Temperature Quadrupole Ion Trap Mass Spectrometer.

    PubMed

    Derkits, David; Wiseman, Alex; Snead, Russell F; Dows, Martina; Harge, Jasmine; Lamp, Jared A; Gronert, Scott

    2016-02-01

    A new, variable-temperature mass spectrometer system is described. By applying polyimide heating tape to the end-cap electrodes of a Bruker (Bremen, Germany) Esquire ion trap, it is possible to vary the effective temperature of the system between 40 and 100°C. The modification does not impact the operation of the ion trap and the heater can be used for extended periods without degradation of the system. The accuracy of the ion trap temperatures was assessed by examining two gas-phase equilibrium processes with known thermochemistry. In each case, the variable-temperature ion trap provided data that were in good accord with literature data, indicating the effective temperature in the ion trap environment was being successfully modulated by the changes in the set-point temperatures on the end-cap electrodes. The new design offers a convenient and effective way to convert commercial ion trap mass spectrometers into variable-temperature instruments. PMID:26483183

  15. A bent electrostatic ion beam trap for simultaneous measurements of fragmentation and ionization of cluster ions.

    PubMed

    Aviv, O; Toker, Y; Errit, M; Bhushan, K G; Pedersen, H B; Rappaport, M L; Heber, O; Schwalm, D; Zajfman, D

    2008-08-01

    We describe a bent electrostatic ion beam trap in which cluster ions of several keV kinetic energy can be stored on a V-shaped trajectory by means of an electrostatic deflector placed between two electrostatic mirrors. While maintaining all the advantages of its linear counterpart [Zajfman et al., Phys. Rev. A 55, R1577 (1997); Dahan et al., Rev. Sci. Instrum. 69, 76 (1998)], such as long storage times, straight segments, and a field-free region for merged or crossed beam experiments, the bent trap allows for simultaneous measurement of charged and neutral fragments and determination of the average kinetic energy released in the fragmentation. These unique properties of the bent trap are illustrated by first results concerning the competition between delayed fragmentation and ionization of Al(n) (-) clusters after irradiation by a short laser pulse. PMID:19044339

  16. The tripole linear ion trap with highly efficient orthogonal ion ejection designed by computer simulations.

    PubMed

    Salazar, Gary A; Masujima, Tsutomu

    2008-05-01

    An ion guide, consisting of three rods carrying three alternating current (AC) voltages symmetrically delayed, called a tripole, was used as a linear ion trap (LIT) and studied by computer simulations. Radial containment of ions was also demonstrated with the pseudopotential which was calculated by approximating the tripole electric potential to the multipoles expansion. This work found a new analyte concentrator, which performs effective ion ejection, and is suitable for use with time-of-flight mass spectrometry. The efficiency of the overall process from the trapping until the ejection was higher than 90%, although some degree of ion spatial and kinetic energy spread which can be corrected with a reflectron was obtained. The reason for the ejection of this tripole linear ion trap (tLIT) lies in the high space available between the rods. The ejection is optimized with the application of focusing voltages, especially suitable for a tripole symmetry (one electrode has a pulse offset voltage and the other two have a fraction of that pulse). The beam is finally well parallelized with a rectangular Einzel lens. PMID:18384193

  17. Inhomogeneous BCS-BEC crossover for trapped cold atoms in optical lattices

    NASA Astrophysics Data System (ADS)

    Amaricci, A.; Privitera, A.; Capone, M.

    2014-05-01

    The BCS-BEC (Bose-Einstein condensation) crossover in a lattice is a powerful paradigm that describes how a superconductor deviates from the Bardeen-Cooper-Schrieffer physics as the attractive interaction increases. Optical lattices loaded with binary mixtures of cold atoms allow one to access this phenomenon experimentally in a clean and controlled way. We show that, however, the possibility to study this phenomenon in actual cold-atoms experiments is limited by the effect of the trapping potential. Real-space dynamical mean-field theory calculations show indeed that interactions and the confining potential conspire to pack the fermions in the center of the trap, which approaches a band insulator when the attraction becomes sizeable. Interestingly, the energy gap is spatially more homogeneous than the superfluid condensate order parameter. We show how this physics reflects in several observables, and we propose an alternative strategy to disentangle the effect of the harmonic potential and measure the intrinsic properties resulting from the interaction strength.

  18. Multi-element logic gates for trapped-ion qubits

    NASA Astrophysics Data System (ADS)

    Tan, T. R.; Gaebler, J. P.; Lin, Y.; Wan, Y.; Bowler, R.; Leibfried, D.; Wineland, D. J.

    2015-12-01

    Precision control over hybrid physical systems at the quantum level is important for the realization of many quantum-based technologies. In the field of quantum information processing (QIP) and quantum networking, various proposals discuss the possibility of hybrid architectures where specific tasks are delegated to the most suitable subsystem. For example, in quantum networks, it may be advantageous to transfer information from a subsystem that has good memory properties to another subsystem that is more efficient at transporting information between nodes in the network. For trapped ions, a hybrid system formed of different species introduces extra degrees of freedom that can be exploited to expand and refine the control of the system. Ions of different elements have previously been used in QIP experiments for sympathetic cooling, creation of entanglement through dissipation, and quantum non-demolition measurement of one species with another. Here we demonstrate an entangling quantum gate between ions of different elements which can serve as an important building block of QIP, quantum networking, precision spectroscopy, metrology, and quantum simulation. A geometric phase gate between a 9Be+ ion and a 25Mg+ ion is realized through an effective spin-spin interaction generated by state-dependent forces induced with laser beams. Combined with single-qubit gates and same-species entangling gates, this mixed-element entangling gate provides a complete set of gates over such a hybrid system for universal QIP. Using a sequence of such gates, we demonstrate a CNOT (controlled-NOT) gate and a SWAP gate. We further demonstrate the robustness of these gates against thermal excitation and show improved detection in quantum logic spectroscopy. We also observe a strong violation of a CHSH (Clauser-Horne-Shimony-Holt)-type Bell inequality on entangled states composed of different ion species.

  19. Multi-element logic gates for trapped-ion qubits.

    PubMed

    Tan, T R; Gaebler, J P; Lin, Y; Wan, Y; Bowler, R; Leibfried, D; Wineland, D J

    2015-12-17

    Precision control over hybrid physical systems at the quantum level is important for the realization of many quantum-based technologies. In the field of quantum information processing (QIP) and quantum networking, various proposals discuss the possibility of hybrid architectures where specific tasks are delegated to the most suitable subsystem. For example, in quantum networks, it may be advantageous to transfer information from a subsystem that has good memory properties to another subsystem that is more efficient at transporting information between nodes in the network. For trapped ions, a hybrid system formed of different species introduces extra degrees of freedom that can be exploited to expand and refine the control of the system. Ions of different elements have previously been used in QIP experiments for sympathetic cooling, creation of entanglement through dissipation, and quantum non-demolition measurement of one species with another. Here we demonstrate an entangling quantum gate between ions of different elements which can serve as an important building block of QIP, quantum networking, precision spectroscopy, metrology, and quantum simulation. A geometric phase gate between a (9)Be(+) ion and a (25)Mg(+) ion is realized through an effective spin-spin interaction generated by state-dependent forces induced with laser beams. Combined with single-qubit gates and same-species entangling gates, this mixed-element entangling gate provides a complete set of gates over such a hybrid system for universal QIP. Using a sequence of such gates, we demonstrate a CNOT (controlled-NOT) gate and a SWAP gate. We further demonstrate the robustness of these gates against thermal excitation and show improved detection in quantum logic spectroscopy. We also observe a strong violation of a CHSH (Clauser-Horne-Shimony-Holt)-type Bell inequality on entangled states composed of different ion species. PMID:26672553

  20. Fully ElectroStatic Ion Traps for β-decay Studies

    NASA Astrophysics Data System (ADS)

    Ron, Guy

    2010-11-01

    Using principles analogous to those of conventional optics it is possible to construct fully electrostatic ion traps which act as a resonant cavity for ion beams. Such traps exhibit an unexpected phenomenon of self-bunching which allows for long lifetimes of trapped ion bunches. Such a trap was originally conceived and developed at the Weimann Institute of Science. Based on this design we are constructing such a trap for use with the LBL IRIS beamline. I will present the principles and design of such a trap. I will further discuss the experimental possibilities afforded, with emphasis on mass spectroscopy and possible measurements of β decay correlations of trapped radioactive ions. Such measurements allow the study of possible standard model extensions affecting the structure of the weak interaction.

  1. Cycle Time Reduction in Trapped Mercury Ion Atomic Frequency Standards

    NASA Technical Reports Server (NTRS)

    Burt, Eric A.; Tjoelker, Robert L.; Taghavi, Shervin

    2011-01-01

    The use of the mercury ion isotope (201)Hg(+) was examined for an atomic clock. Taking advantage of the faster optical pumping time in (201)Hg(+) reduces both the state preparation and the state readout times, thereby decreasing the overall cycle time of the clock and reducing the impact of medium-term LO noise on the performance of the frequency standard. The spectral overlap between the plasma discharge lamp used for (201)Hg(+) state preparation and readout is much larger than that of the lamp used for the more conventional (199)Hg(+). There has been little study of (201)Hg(+) for clock applications (in fact, all trapped ion clock work in mercury has been with (199)Hg(+); however, recently the optical pumping time in (201)Hg(+) has been measured and found to be 0.45 second, or about three times faster than in (199)Hg(+) due largely to the better spectral overlap. This can be used to reduce the overall clock cycle time by over 2 seconds, or up to a factor of 2 improvement. The use of the (201)Hg(+) for an atomic clock is totally new. Most attempts to reduce the impact of LO noise have focused on reducing the interrogation time. In the trapped ion frequency standards built so far at JPL, the optical pumping time is already at its minimum so that no enhancement can be had by shortening it. However, by using (201)Hg(+), this is no longer the case. Furthermore, integrity monitoring, the mechanism that determines whether the clock is functioning normally, cannot happen faster than the clock cycle time. Therefore, a shorter cycle time will enable quicker detection of failure modes and recovery from them.

  2. Integrated fiber-mirror ion trap for strong ion-cavity coupling

    SciTech Connect

    Brandstätter, B. Schüppert, K.; Casabone, B.; Friebe, K.; Stute, A.; Northup, T. E.; McClung, A.; Schmidt, P. O.; Deutsch, C.; Reichel, J.

    2013-12-15

    We present and characterize fiber mirrors and a miniaturized ion-trap design developed to integrate a fiber-based Fabry-Perot cavity (FFPC) with a linear Paul trap for use in cavity-QED experiments with trapped ions. Our fiber-mirror fabrication process not only enables the construction of FFPCs with small mode volumes, but also allows us to minimize the influence of the dielectric fiber mirrors on the trapped-ion pseudopotential. We discuss the effect of clipping losses for long FFPCs and the effect of angular and lateral displacements on the coupling efficiencies between cavity and fiber. Optical profilometry allows us to determine the radii of curvature and ellipticities of the fiber mirrors. From finesse measurements, we infer a single-atom cooperativity of up to 12 for FFPCs longer than 200 μm in length; comparison to cavities constructed with reference substrate mirrors produced in the same coating run indicates that our FFPCs have similar scattering losses. We characterize the birefringence of our fiber mirrors, finding that careful fiber-mirror selection enables us to construct FFPCs with degenerate polarization modes. As FFPCs are novel devices, we describe procedures developed for handling, aligning, and cleaning them. We discuss experiments to anneal fiber mirrors and explore the influence of the atmosphere under which annealing occurs on coating losses, finding that annealing under vacuum increases the losses for our reference substrate mirrors. X-ray photoelectron spectroscopy measurements indicate that these losses may be attributable to oxygen depletion in the mirror coating. Special design considerations enable us to introduce a FFPC into a trapped ion setup. Our unique linear Paul trap design provides clearance for such a cavity and is miniaturized to shield trapped ions from the dielectric fiber mirrors. We numerically calculate the trap potential in the absence of fibers. In the experiment additional electrodes can be used to compensate

  3. Electron Flood Charge Compensation Device for Ion Trap Secondary Ion Mass Spectrometry

    SciTech Connect

    Appelhans, Anthony David; Ward, Michael Blair; Olson, John Eric

    2002-11-01

    During secondary ion mass spectrometry (SIMS) analyses of organophosphorous compounds adsorbed onto soils, the measured anion signals were lower than expected and it was hypothesized that the low signals could be due to sample charging. An electron flood gun was designed, constructed and used to investigate sample charging of these and other sample types. The flood gun was integrated into one end cap of an ion trap secondary ion mass spectrometer and the design maintained the geometry of the self-stabilizing extraction optics used in this instrument. The SIMION ion optics program was used to design the flood gun, and experimental results agreed with the predicted performance. Results showed the low anion signals from the soils were not due to sample charging. Other insulating and conducting samples were tested using both a ReO4- and a Cs+ primary ion beam. The proximity of the sample and electron source to the ion trap aperture resulted in generation of background ions in the ion trap via electron impact (EI) ionization during the period the electron gun was flooding the sample region. When using the electron gun with the ReO4- primary beam, the required electron current was low enough that the EI background was negligible; however, the high electron flood current required with the Cs+ beam produced background EI ions that degraded the quality of the mass spectra. The consequences of the EI produced cations will have to be evaluated on a sample-by-sample basis when using electron flood. It was shown that the electron flood gun could be intentionally operated to produce EI spectra in this instrument. This offers the opportunity to measure, nearly simultaneously, species evaporating from a sample, via EI, and species bound to the surface, via SIMS.

  4. Buffer gas loading and Doppler cooling of strontium ions in a planar Paul trap

    NASA Astrophysics Data System (ADS)

    Clark, Robert; Brown, Kenneth; Labaziewicz, Jaroslaw; Richerme, Philip; Chuang, Isaac

    2006-05-01

    Traditional geometries for ion traps involve three dimensional structures which may be difficult to assemble in complex geometries demanded by applications such as large-scale quantum computation. Planar Paul traps provide an alternative approach [Chiaverini et. al., Quant. Inf. Comput. 5, 419 (2005)], in which the RF and DC electrodes are placed in a single plane, providing simpler fabrication and greater optical access to the trapped ions. We have designed and constructed a planar Paul trap using copper electrodes on a Rogers 4350 substrate. Strontium ions were loaded into this structure at UHV, and also at high vacuum using helium buffer gas cooling. The temperature of the ion cloud as a function of buffer gas pressure is compared to predictions from a model which includes ion-helium collisions and RF heating. The measured trap parameters, including secular frequencies, trap depth, and RF heating rates, agree well with a pseudopotential model based on finite-element electrostatic calculations.

  5. Operation of a planar-electrode ion-trap array with adjustable RF electrodes

    NASA Astrophysics Data System (ADS)

    Kumph, M.; Holz, P.; Langer, K.; Meraner, M.; Niedermayr, M.; Brownnutt, M.; Blatt, R.

    2016-02-01

    One path to realizing systems of trapped atomic ions suitable for large-scale quantum computing and simulation is to create a two-dimensional (2D) array of ion traps. Interactions between nearest-neighbouring ions could then be turned on and off by tuning the ions’ relative positions and frequencies. We demonstrate and characterize the operation of a planar-electrode ion-trap array. By driving the trap with a network of phase-locked radio-frequency resonators which provide independently variable voltage amplitudes we vary the position and motional frequency of a Ca+ ion in two-dimensions within the trap array. Work on fabricating a miniaturised form of this 2D trap array is also described, which could ultimately provide a viable architecture for large-scale quantum simulations.

  6. Rapid, Site-Selective Loading of a Scalable Array of Trapped Ions

    NASA Astrophysics Data System (ADS)

    Bruzewicz, Colin; McConnell, Robert; Chiaverini, John; Sage, Jeremy

    2016-05-01

    Rapid trap reloading is a requirement for any scalable quantum information processor based on trapped-ion qubits. Even cryogenic systems with trap lifetimes in excess of 10 hours will require loading rates of approximately 100 s-1 to maintain arrays of millions of ions. Further, the reloading process should not introduce unacceptable levels of decoherence into other ions within the array. Here, we demonstrate rapid, site-selective, random-access loading of a 2x2 array of trapped ions that satisfies the major criteria for scalable quantum processing. This scheme uses a continuous flux of pre-cooled strontium atoms and a pair of orthogonal photo-ionization lasers to load surface-electrode point Paul traps at average rates greater than 400 s-1. Additionally, we have conducted a series of Ramsey experiments to measure the effects of loading on the coherence of nearby trapped ions.

  7. Physical properties of a trapped two-level ion decaying by thermal and squeezed vacuum reservoirs

    NASA Astrophysics Data System (ADS)

    Yazdanpanah, N.; Tavassoly, M. K.

    2016-01-01

    In this paper, we first study the interaction between a trapped two-level ion with a field reservoir in a general form. Then, we use thermal and squeezed vacuum reservoirs to continue our investigation. We try to find the equation of motion for the whole system density operator by applying the Weisskopf theory. Next, we evaluate the explicit form of the density matrix elements analytically. In the obtained density matrix elements, we arrive at some physical parameters of the trapped ion system as well as the applied field reservoirs by which one can control the transition probabilities between the trapped ionic states. We also introduce some hermitian operators for the trapped ion system and calculate the expectation values of their time evolution by considering the mentioned two reservoirs. In the continuation, we design a system for measuring the hermitian trapped ion's operators theoretically. Finally, we find a way to transport the information of the trapped ion system by our proposed quantum processor.

  8. Adsorption of ions onto nanosolids dispersed in liquid crystals: Towards understanding the ion trapping effect in nanocolloids

    NASA Astrophysics Data System (ADS)

    Garbovskiy, Yuriy

    2016-05-01

    The ion capturing effect in liquid crystal nanocolloids was quantified by means of the ion trapping coefficient. The dependence of the ion trapping coefficient on the concentration of nano-dopants and their ionic purity was calculated for a variety of nanosolids dispersed in liquid crystals: carbon nanotubes, graphene nano-flakes, diamond nanoparticles, anatase nanoparticles, and ferroelectric nanoparticles. The proposed method perfectly fits existing experimental data and can be useful in the design of highly efficient ion capturing nanomaterials.

  9. Fundamentals of Trapped Ion Mobility Spectrometry Part II: Fluid Dynamics

    NASA Astrophysics Data System (ADS)

    Silveira, Joshua A.; Michelmann, Karsten; Ridgeway, Mark E.; Park, Melvin A.

    2016-04-01

    Trapped ion mobility spectrometry (TIMS) is a new high resolution (R up to ~300) separation technique that utilizes an electric field to hold ions stationary against a moving gas. Recently, an analytical model for TIMS was derived and, in part, experimentally verified. A central, but not yet fully explored, component of the model involves the fluid dynamics at work. The present study characterizes the fluid dynamics in TIMS using simulations and ion mobility experiments. Results indicate that subsonic laminar flow develops in the analyzer, with pressure-dependent gas velocities between ~120 and 170 m/s measured at the position of ion elution. One of the key philosophical questions addressed is: how can mobility be measured in a dynamic system wherein the gas is expanding and its velocity is changing? We noted previously that the analytically useful work is primarily done on ions as they traverse the electric field gradient plateau in the analyzer. In the present work, we show that the position-dependent change in gas velocity on the plateau is balanced by a change in pressure and temperature, ultimately resulting in near position-independent drag force. That the drag force, and related variables, are nearly constant allows for the use of relatively simple equations to describe TIMS behavior. Nonetheless, we derive a more comprehensive model, which accounts for the spatial dependence of the flow variables. Experimental resolving power trends were found to be in close agreement with the theoretical dependence of the drag force, thus validating another principal component of TIMS theory.

  10. Fundamentals of Trapped Ion Mobility Spectrometry Part II: Fluid Dynamics.

    PubMed

    Silveira, Joshua A; Michelmann, Karsten; Ridgeway, Mark E; Park, Melvin A

    2016-04-01

    Trapped ion mobility spectrometry (TIMS) is a new high resolution (R up to ~300) separation technique that utilizes an electric field to hold ions stationary against a moving gas. Recently, an analytical model for TIMS was derived and, in part, experimentally verified. A central, but not yet fully explored, component of the model involves the fluid dynamics at work. The present study characterizes the fluid dynamics in TIMS using simulations and ion mobility experiments. Results indicate that subsonic laminar flow develops in the analyzer, with pressure-dependent gas velocities between ~120 and 170 m/s measured at the position of ion elution. One of the key philosophical questions addressed is: how can mobility be measured in a dynamic system wherein the gas is expanding and its velocity is changing? We noted previously that the analytically useful work is primarily done on ions as they traverse the electric field gradient plateau in the analyzer. In the present work, we show that the position-dependent change in gas velocity on the plateau is balanced by a change in pressure and temperature, ultimately resulting in near position-independent drag force. That the drag force, and related variables, are nearly constant allows for the use of relatively simple equations to describe TIMS behavior. Nonetheless, we derive a more comprehensive model, which accounts for the spatial dependence of the flow variables. Experimental resolving power trends were found to be in close agreement with the theoretical dependence of the drag force, thus validating another principal component of TIMS theory. Graphical Abstract ᅟ. PMID:26864793

  11. High-precision force sensing using a single trapped ion

    PubMed Central

    Ivanov, Peter A.; Vitanov, Nikolay V.; Singer, Kilian

    2016-01-01

    We introduce quantum sensing schemes for measuring very weak forces with a single trapped ion. They use the spin-motional coupling induced by the laser-ion interaction to transfer the relevant force information to the spin-degree of freedom. Therefore, the force estimation is carried out simply by observing the Ramsey-type oscillations of the ion spin states. Three quantum probes are considered, which are represented by systems obeying the Jaynes-Cummings, quantum Rabi (in 1D) and Jahn-Teller (in 2D) models. By using dynamical decoupling schemes in the Jaynes-Cummings and Jahn-Teller models, our force sensing protocols can be made robust to the spin dephasing caused by the thermal and magnetic field fluctuations. In the quantum-Rabi probe, the residual spin-phonon coupling vanishes, which makes this sensing protocol naturally robust to thermally-induced spin dephasing. We show that the proposed techniques can be used to sense the axial and transverse components of the force with a sensitivity beyond the range, i.e. in the (xennonewton, 10−27). The Jahn-Teller protocol, in particular, can be used to implement a two-channel vector spectrum analyzer for measuring ultra-low voltages. PMID:27306426

  12. High-precision force sensing using a single trapped ion.

    PubMed

    Ivanov, Peter A; Vitanov, Nikolay V; Singer, Kilian

    2016-01-01

    We introduce quantum sensing schemes for measuring very weak forces with a single trapped ion. They use the spin-motional coupling induced by the laser-ion interaction to transfer the relevant force information to the spin-degree of freedom. Therefore, the force estimation is carried out simply by observing the Ramsey-type oscillations of the ion spin states. Three quantum probes are considered, which are represented by systems obeying the Jaynes-Cummings, quantum Rabi (in 1D) and Jahn-Teller (in 2D) models. By using dynamical decoupling schemes in the Jaynes-Cummings and Jahn-Teller models, our force sensing protocols can be made robust to the spin dephasing caused by the thermal and magnetic field fluctuations. In the quantum-Rabi probe, the residual spin-phonon coupling vanishes, which makes this sensing protocol naturally robust to thermally-induced spin dephasing. We show that the proposed techniques can be used to sense the axial and transverse components of the force with a sensitivity beyond the range, i.e. in the (xennonewton, 10(-27)). The Jahn-Teller protocol, in particular, can be used to implement a two-channel vector spectrum analyzer for measuring ultra-low voltages. PMID:27306426

  13. High-precision force sensing using a single trapped ion

    NASA Astrophysics Data System (ADS)

    Ivanov, Peter A.; Vitanov, Nikolay V.; Singer, Kilian

    2016-06-01

    We introduce quantum sensing schemes for measuring very weak forces with a single trapped ion. They use the spin-motional coupling induced by the laser-ion interaction to transfer the relevant force information to the spin-degree of freedom. Therefore, the force estimation is carried out simply by observing the Ramsey-type oscillations of the ion spin states. Three quantum probes are considered, which are represented by systems obeying the Jaynes-Cummings, quantum Rabi (in 1D) and Jahn-Teller (in 2D) models. By using dynamical decoupling schemes in the Jaynes-Cummings and Jahn-Teller models, our force sensing protocols can be made robust to the spin dephasing caused by the thermal and magnetic field fluctuations. In the quantum-Rabi probe, the residual spin-phonon coupling vanishes, which makes this sensing protocol naturally robust to thermally-induced spin dephasing. We show that the proposed techniques can be used to sense the axial and transverse components of the force with a sensitivity beyond the range, i.e. in the (xennonewton, 10‑27). The Jahn-Teller protocol, in particular, can be used to implement a two-channel vector spectrum analyzer for measuring ultra-low voltages.

  14. Systematic Comparison of a Two-dimensional Ion Trap and a Three-dimensional Ion Trap Mass Spectrometer in Proteomics*S

    PubMed Central

    Mayya, Viveka; Rezaul, Karim; Cong, Yu-Sheng; Han, David

    2006-01-01

    The utility and advantages of the recently introduced two-dimensional quadrupole ion trap mass spectrometer in proteomics over the traditional three-dimensional ion trap mass spectrometer have not been systematically characterized. Here we rigorously compared the performance of these two platforms by using over 100,000 tandem mass spectra acquired with identical complex peptide mixtures and acquisition parameters. Specifically we compared four factors that are critical for a successful proteomic study: 1) the number of proteins identified, 2) sequence coverage or the number of peptides identified for every protein, 3) the data base matching SEQUEST Xcorr and Sp score, and 4) the quality of the fragment ion series of peptides. We found a 4–6-fold increase in the number of peptides and proteins identified on the two-dimensional ion trap mass spectrometer as a direct result of improvement in all the other parameters examined. Interestingly more than 70% of the doubly and triply charged peptides, but not the singly charged peptides, showed better quality of fragmentation spectra on the two-dimensional ion trap. These results highlight specific advantages of the two-dimensional ion trap over the conventional three-dimensional ion traps for protein identification in proteomic experiments. PMID:15608339

  15. Cold ion demagnetization near the X-line of magnetic reconnection

    NASA Astrophysics Data System (ADS)

    Toledo-Redondo, Sergio; André, Mats; Khotyaintsev, Yuri V.; Vaivads, Andris; Walsh, Andrew; Li, Wenya; Graham, Daniel B.; Lavraud, Benoit; Masson, Arnaud; Aunai, Nicolas; Divin, Andrey; Dargent, Jeremy; Fuselier, Stephen; Gershman, Daniel J.; Dorelli, John; Giles, Barbara; Avanov, Levon; Pollock, Craig; Saito, Yoshifumi; Moore, Thomas E.; Coffey, Victoria; Chandler, Michael O.; Lindqvist, Per-Arne; Torbert, Roy; Russell, Christopher T.

    2016-07-01

    Although the effects of magnetic reconnection in magnetospheres can be observed at planetary scales, reconnection is initiated at electron scales in a plasma. Surrounding the electron diffusion region, there is an Ion-Decoupling Region (IDR) of the size of the ion length scales (inertial length and gyroradius). Reconnection at the Earth's magnetopause often includes cold magnetospheric (few tens of eV), hot magnetospheric (10 keV), and magnetosheath (1 keV) ions, with different gyroradius length scales. We report observations of a subregion inside the IDR of the size of the cold ion population gyroradius (˜15 km) where the cold ions are demagnetized and accelerated parallel to the Hall electric field. Outside the subregion, cold ions follow the E × B motion together with electrons, while hot ions are demagnetized. We observe a sharp cold ion density gradient separating the two regions, which we identify as the cold and hot IDRs.

  16. Limiting temperature of sympathetically cooled ions in a radio-frequency trap

    SciTech Connect

    Hasegawa, Taro; Shimizu, Tadao

    2003-01-01

    The limiting temperature achieved by sympathetic cooling in an rf trap is calculated with a theoretical model in which no fitting parameters are used. The calculated result agrees well with observation. The dependence of the temperature on trapping parameters and ion mass is also analyzed. The results can be used for designing an rf trap system.

  17. Plug-and-Play Planar Ion Traps for Scalable Quantum Computation and Simulation

    NASA Astrophysics Data System (ADS)

    Amini, Jason; Denison, Douglas; Doret, S. Charles; Faircloth, Daniel; Hayden, Harley; Killian, Tyler; Landgren, David; Martin, Kevin; Merrill, True; Ozakin, Arkadas; Pai, C. S.; Shaikh, Fayaz; Shappert, Chris; Volin, Curtis; Wright, Ken; Harter, Alexa; Slusher, Richart

    2011-05-01

    At the heart of most ion-based quantum information processing and simulation efforts is an RF-Paul trap to confine the ion qubits. Cutting edge experiments are transitioning from a few qubits to a few tens of qubits with many more qubits envisioned for the future. The underlying ion traps need to both grow with the experiments and provide additional features that can simplify and extend these experiments. The Georgia Tech Research Institute (GTRI) is developing modeling and fabrication processes for these new generations of ion traps using silicon VLSI technology in surface- electrode geometries. Verified by detailed in-house trap characterization, GTRI has fabricated traps that approach the plug- and-play ideal and demonstrate reliable ion loading and transport, long dark lifetimes, and stable ion chains. Additional features are in development including junctions, integrated GHz range current guides for global qubit rotations, and micromirrors for light collection.

  18. Phase-modulated spin-motional decoupling with trapped ions

    NASA Astrophysics Data System (ADS)

    Edmunds, Claire; Milne, Alistair; Mavadia, Sandeep; Green, Todd; Biercuk, Michael

    We present a technique to minimize residual spin-motional entanglement after a phonon-mediated entangling gate in trapped 171Yb+ ion qubits. Phonon-mediated gates, such as the Mølmer-Sørensen gate, engineer spin-spin entanglement by coupling the qubits to their collective modes of motion. Consequently, a major experimental limitation is residual motional entanglement at the conclusion of the gate, resulting in a degradation of the final spin state purity. Our work utilizes phase-modulated pulse sequences to decouple the qubits from multiple motional modes simultaneously at a variable gate time. In addition, we extend this technique to the suppression of time-dependent noise using concatenated gate sequences, which allows for the recovery of a higher purity spin state. Using a single, experimentally controllable modulation parameter we are able to achieve more optimal quantum control in these gate sequences.

  19. Analogue of cosmological particle creation in an ion trap.

    PubMed

    Schützhold, Ralf; Uhlmann, Michael; Petersen, Lutz; Schmitz, Hector; Friedenauer, Axel; Schätz, Tobias

    2007-11-16

    We study phonons in a dynamical chain of ions confined by a trap with a time-dependent (axial) potential strength and demonstrate that they behave in the same way as quantum fields in an expanding or contracting Universe. Based on this analogy, we present a scheme for the detection of the analogue of cosmological particle creation which should be feasible with present day technology. In order to test the quantum nature of the particle creation mechanism and to distinguish it from classical effects such as heating, we propose to measure the two-phonon amplitude via the 2nd red sideband transition and to compare it with the one-phonon amplitude (1st red sideband). PMID:18233131

  20. Analogue of Cosmological Particle Creation in an Ion Trap

    SciTech Connect

    Schuetzhold, Ralf; Uhlmann, Michael; Petersen, Lutz; Schmitz, Hector; Friedenauer, Axel; Schaetz, Tobias

    2007-11-16

    We study phonons in a dynamical chain of ions confined by a trap with a time-dependent (axial) potential strength and demonstrate that they behave in the same way as quantum fields in an expanding or contracting Universe. Based on this analogy, we present a scheme for the detection of the analogue of cosmological particle creation which should be feasible with present day technology. In order to test the quantum nature of the particle creation mechanism and to distinguish it from classical effects such as heating, we propose to measure the two-phonon amplitude via the 2nd red sideband transition and to compare it with the one-phonon amplitude (1st red sideband)

  1. Gate Set Tomography on a trapped ion qubit

    NASA Astrophysics Data System (ADS)

    Nielsen, Erik; Blume-Kohout, Robin; Gamble, John; Rundinger, Kenneth; Mizrahi, Jonathan; Sterk, Johathan; Maunz, Peter

    2015-03-01

    We present enhancements to gate-set tomography (GST), which is a framework in which an entire set of quantum logic gates (including preparation and measurement) can be fully characterized without need for pre-calibrated operations. Our new method, ``extended Linear GST'' (eLGST) uses fast, reliable analysis of structured long gate sequences to deliver tomographic precision at the Heisenberg limit with GST's calibration-free framework. We demonstrate this precision on a trapped-ion qubit, and show significant (orders of magnitude) advantage over both standard process tomography and randomized benchmarking. This work was supported by the Laboratory Directed Research and Development (LDRD) program at Sandia National Laboratories. Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under Contract DE-AC04-94AL85000.

  2. Dielectronic Recombination of Highly Charged Ions Using an Electron Beam Ion Trap

    NASA Astrophysics Data System (ADS)

    Dewitt, David Russell

    1992-01-01

    Dielectronic Recombination is an important electron -ion recombination process which affects many aspects of plasmas. This work presents experimental measurements of relative dielectronic recombination cross sections for three highly charged ions: hydrogenlike argon (Ar ^{17+}), heliumlike argon (Ar ^{16+}), and neonlike xenon (Xe ^{44+}). The dielectronic recombination cross sections are compared to theoretical resonance strengths. Excellent agreement is found overall. The energy resolution of the experimental measurements is 18 eV FWHM. These experiments make use of the ion extraction system recently installed on the Electron Beam Ion Trap (EBIT). With this technique the interactions are measured through measurement of relative ion populations rather than relative x-ray intensities. Following a general introduction an overview of the theory of dielectronic recombination is presented which includes the calculation of the rate coefficient, the effects of dielectronic recombination on relative ion populations, and the relationship between the rate coefficient and the cross sections and resonance strengths. Both relativistic and nonrelativistic aspects of the theory are discussed and a sketch of the Multiconfiguration Dirac Fock (MCDF) method used to obtain theoretical cross sections is given. The Electron Beam Ion Trap (EBIT) is described in detail. Relations between the important operating parameters, such as the depth of the potential well and the electron beam current, are discussed. The ion extraction system is described. Physical processes which affect the populations of ions in the trap are discussed including evaporative cooling. The general rate equations for the time development of the ion populations are presented. The separate experiments for the three ions Ar ^{17+}, Ar^ {16+}, and Xe^{44+ } are then examined in detail. The KLL, KLM, KLN, KLO and KLP groups of resonances of hydogenlike argon as well as the LMM, LMN, LMO, LMP and LMQ groups of resonances

  3. Velocity diffusion and radiation trapping force in a one-dimensional expansion of cold atomic clouds in a magneto-optical trap

    SciTech Connect

    Pradhan, S.; Mayya, Y. S.; Jagatap, B. N.

    2007-09-15

    We experimentally investigate one-dimensional (1D) expansion of a cold cloud of cesium atoms in orthogonal 2D configuration of near resonant laser beams by temporally modulating a pair of counterpropagating trapping beams of a magneto-optical trap (MOT). The cloud is observed to undergo ballistic expansion followed by superballistic explosive growth due to the fluctuations of the 2D radiation force. A model based on the theory of Brownian motion is developed and a comparison of experiments with theory is shown to provide a direct measure of the velocity diffusion coefficient. We also observe sudden contraction of the cloud immediately after switching off the pair of trapping beams, which provides direct evidence for the existence of the radiation trapping force in a MOT.

  4. 'Programming' Electron Beam Ion Traps To Produce Atomic Data Relevant To Plasma Physics

    SciTech Connect

    Currell, Fred; O'Rourke, Brian; Kavanagh, Anthony; Li Yueming; Nakamura, Nobuyuki; Ohtani, Shunsuke; Watanabe, Hirofumi

    2009-09-10

    After a brief review of the processes taking place in electron beam ions traps (EBITs), the means by which EBITs are used to make measurements of electron impact ionization cross-sections and dielectronic recombination resonance strengths are discussed. In particular, results from a study involving holmium ions extracted from an electron beam ion trap are used to illustrate a technique for studying dielectronic recombination in open-shell target ions.

  5. Low jitter metal vapor vacuum arc ion source for electron beam ion trap injections

    SciTech Connect

    Holland, Glenn E.; Boyer, Craig N.; Seely, John F.; Tan, J.N.; Pomeroy, J.M.; Gillaspy, J.D.

    2005-07-15

    We describe a metal vapor vacuum arc (MeVVA) ion source containing eight different cathodes that are individually selectable via the control electronics which does not require moving components in vacuum. Inside the vacuum assembly, the arc plasma is produced by means of a 30 {mu}s pulse (26 kV,125 A) delivering 2.4 mC of charge to the cathode sample material. The trigger jitter is minimized (<200 ns) to improve the capture efficiency of the ions which are injected into an ion trap. During a single discharge, the over-damped pulse produces an ion flux of 8.4x10{sup 9} ions/cm{sup 2}, measured by an unbiased Faraday cup positioned 20 cm from the extractor grid, at discharge rates up to 5 Hz. The electronic triggering of the discharge is via a fiber optic interface. We present the design, fabrication details, and performance of this MeVVA, recently installed on the National Institute of Standards and Technology electron beam ion trap (EBIT)

  6. EBIT in the Magnetic Trapping Mode: Mass Spectrometry, Atomic Lifetime Measurements, and Charge Transfer Reactions of Highly Charged Atomic Ions

    SciTech Connect

    Schweikhard, L; Beiersdorfer, P; Trabert, E

    2001-07-10

    Although it may sound like a contradiction in terms, the electron beam ion trap (EBIT) works as an ion trap even when the electron beam is switched off. We present various experiments that exploit the ''magnetic trapping mode'' for investigations of ion confinement, charge exchange processes, atomic lifetime and ion mass measurements.

  7. Stability Diagrams for Paul Ion Traps Driven by Two-Frequencies.

    PubMed

    Possa, Gabriela C; Roncaratti, Luiz F

    2016-07-14

    In this paper, we present and discuss stability diagrams for Paul traps driven by two ac voltages. In contrast to a typical Paul trap, here we suggest a secondary ac voltage whose frequency is twice the frequency of the primary one. The ratio between their amplitudes can be used to expand the region of stability and to access different states of motion of trapped ions. This provides a further mechanism to trap, cool, and manipulate single ions and also to improve the experimental framework where ion clouds and crystals can be prepared and controlled. Such approach opens the possibility of designing more sophisticated trapping architectures, leading to a wide variety of applications on ion trap research and mass analysis techniques. PMID:26881458

  8. Single-qubit-gate error below 10{sup -4} in a trapped ion

    SciTech Connect

    Brown, K. R.; Wilson, A. C.; Colombe, Y.; Ospelkaus, C.; Meier, A. M.; Knill, E.; Leibfried, D.; Wineland, D. J.

    2011-09-15

    With a {sup 9}Be{sup +} trapped-ion hyperfine-state qubit, we demonstrate an error probability per randomized single-qubit gate of 2.0(2)x10{sup -5}, below the threshold estimate of 10{sup -4} commonly considered sufficient for fault-tolerant quantum computing. The {sup 9}Be{sup +} ion is trapped above a microfabricated surface-electrode ion trap and is manipulated with microwaves applied to a trap electrode. The achievement of low single-qubit-gate errors is an essential step toward the construction of a scalable quantum computer.

  9. Adiabatic coherent control in the anharmonic ion trap: Numerical analysis of vibrational anharmonicities

    SciTech Connect

    Wang Lei; Babikov, Dmitri

    2011-02-15

    Anharmonicity of the quantized motional states of ions in a Paul trap can be utilized to address the state-to-state transitions selectively and control the motional modes of trapped ions coherently and adiabatically [Zhao and Babikov, Phys. Rev. A 77, 012338 (2008)]. In this paper we study two sources of the vibrational anharmonicity in the ion traps: the intrinsic Coulomb anharmonicity due to ion-ion interactions and the external anharmonicity of the trapping potential. An accurate numerical approach is used to compute energies and wave functions of vibrational eigenstates. The magnitude of the Coulomb anharmonicity is determined and shown to be insufficient for successful control. In contrast, anharmonicity of the trapping potential allows one to control the motion of ions very efficiently using the time-varying electric fields. Optimal control theory is used to derive the control pulses. One ion in a slightly anharmonic trap can be easily controlled. In the two- and three-ion systems the symmetric stretching mode is dark and cannot be controlled at all. The other two normal modes of the three-ion system can be controlled and used, for example, to encode a two-qubit system into the motional states of ions. A trap architecture that allows the necessary amount of vibrational anharmonicity to be achieved is proposed.

  10. Extending the Dynamic Range of the Ion Trap by Differential Mobility Filtration

    NASA Astrophysics Data System (ADS)

    Hall, Adam B.; Coy, Stephen L.; Kafle, Amol; Glick, James; Nazarov, Erkinjon; Vouros, Paul

    2013-09-01

    A miniature, planar, differential ion mobility spectrometer (DMS) was interfaced to an LCQ classic ion trap to conduct selective ion filtration prior to mass analysis in order to extend the dynamic range of the trap. Space charge effects are known to limit the functional ion storage capacity of ion trap mass analyzers and this, in turn, can affect the quality of the mass spectral data generated. This problem is further exacerbated in the analysis of mixtures where the indiscriminate introduction of matrix ions results in premature trap saturation with non-targeted species, thereby reducing the number of parent ions that may be used to conduct MS/MS experiments for quantitation or other diagnostic studies. We show that conducting differential mobility-based separations prior to mass analysis allows the isolation of targeted analytes from electrosprayed mixtures preventing the indiscriminate introduction of matrix ions and premature trap saturation with analytically unrelated species. Coupling these two analytical techniques is shown to enhance the detection of a targeted drug metabolite from a biological matrix. In its capacity as a selective ion filter, the DMS can improve the analytical performance of analyzers such as quadrupole (3D or linear) and ion cyclotron resonance (FT-ICR) ion traps that depend on ion accumulation.

  11. Extending the Dynamic Range of the Ion Trap by Differential Mobility Filtration

    PubMed Central

    Hall, Adam B.; Coy, Stephen L.; Kafle, Amol; Glick, James; Nazarov, Erkinjon

    2013-01-01

    A miniature, planar, differential ion mobility spectrometer (DMS) was interfaced to an LCQ classic ion trap to conduct selective ion filtration prior to mass analysis in order to extend the dynamic range of the trap. Space charge effects are known to limit the functional ion storage capacity of ion trap mass analyzers and this, in turn, can affect the quality of the mass spectral data generated. This problem is further exacerbated in the analysis of mixtures where the indiscriminate introduction of matrix ions results in premature trap saturation with non-targeted species, thereby reducing the number of parent ions that may be used to conduct MS/MS experiments for quantitation or other diagnostic studies. We show that conducting differential mobility-based separations prior to mass analysis allows the isolation of targeted analytes from electrosprayed mixtures preventing the indiscriminate introduction of matrix ions and premature trap saturation with analytically unrelated species. Coupling these two analytical techniques is shown to enhance the detection of a targeted drug metabolite from a biological matrix. In its capacity as a selective ion filter, the DMS can improve the analytical performance of analyzers such as quadrupole (3-D or linear) and ion cyclotron resonance (FT-ICR) ion traps that depend on ion accumulation. PMID:23797861

  12. Technologies for trapped-ion quantum information systems - Progress toward scalability with hybrid systems

    NASA Astrophysics Data System (ADS)

    Eltony, Amira M.; Gangloff, Dorian; Shi, Molu; Bylinskii, Alexei; Vuletić, Vladan; Chuang, Isaac L.

    2016-03-01

    Scaling up from prototype systems to dense arrays of ions on chip, or vast networks of ions connected by photonic channels, will require developing entirely new technologies that combine miniaturized ion trapping systems with devices to capture, transmit, and detect light, while refining how ions are confined and controlled. Building a cohesive ion system from such diverse parts involves many challenges, including navigating materials incompatibilities and undesired coupling between elements. Here, we review our recent efforts to create scalable ion systems incorporating unconventional materials such as graphene and indium tin oxide, integrating devices like optical fibers and mirrors, and exploring alternative ion loading and trapping techniques.

  13. X-ray spectroscopy of highly-ionized atoms in an electron beam ion trap (EBIT)

    SciTech Connect

    Marrs, R.E.; Bennett, C.; Chen, M.H.; Cowan, T.; Dietrich, D.; Henderson, J.R.; Knapp, D.A.; Levine, M.A.; Schneider, M.B.; Scofield, J.H.

    1988-01-01

    An Electron Beam Ion Trap at Lawrence Livermore National Laboratory is being used to produce and trap very-highly-charged-ions (q /le/ 70+) for x-ray spectroscopy measurements. Recent measurements of dielectronic recombination, electron impact excitation and transition energies are presented. 15 refs., 12 figs., 1 tab.

  14. Why is sideband mass spectrometry possible with ions in a Penning trap?

    PubMed

    Gabrielse, G

    2009-05-01

    Many masses, particularly the masses of unstable nuclei, are measured with ions in Penning traps by determining the frequency of a driving force that most efficiently couples two of the three motions of trapped ions. A missing explanation of why such sideband mass spectroscopy works, contrary to simple estimates, begins with the established Brown-Gabrielse invariance theorem. PMID:19518777

  15. Why Is Sideband Mass Spectrometry Possible with Ions in a Penning Trap?

    SciTech Connect

    Gabrielse, G.

    2009-05-01

    Many masses, particularly the masses of unstable nuclei, are measured with ions in Penning traps by determining the frequency of a driving force that most efficiently couples two of the three motions of trapped ions. A missing explanation of why such sideband mass spectroscopy works, contrary to simple estimates, begins with the established Brown-Gabrielse invariance theorem.

  16. IDENTIFICATION OF TRIFLURALIN METABOLITIES IN SOIL USING ION-TRAP LC/MS/MS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Trifluralin degradation in soils is complex, potentially resulting in the formation of 28 metabolites. The objective of this research was to develop an approach for the identification of trifluralin metabolites in soils using ion-trap LC/mass spectrometry (ion-trap LC/MS/MS). Authentic standards of ...

  17. a Novel Method to Measure Spectra of Cold Molecular Ions

    NASA Astrophysics Data System (ADS)

    Chakrabarty, Satrajit; Holz, Mathias; Campbell, Ewen; Banerjee, Agniva; Gerlich, Dieter; Maier, John P.

    2014-06-01

    A universal method has been developed in our group for measuring the spectra of molecular ions in a 22-pole radio frequency trap at low temperatures. It is based on laser induced inhibition of complex growth (LIICG)1. At low temperatures and high number densities of buffer gas, helium attaches to ions via ternary association. The formation of these weakly bound complexes, however, is inhibited following resonant absorption of the bare molecular ion. The first successful measurements have been demonstrated on the A 2Π_u ← X ^2Σ_g^+ electronic transition of N_2^+, with some thousand N_2^+ ions, helium densities of 1015 cm-3, and storage times of 1 s. The reduction in the number of N_2+-He complexes is the result of an interplay between excitation, radiative and collisional cooling, ternary association, and collision induced dissociation, and is explained using a kinetic model. The method is also applicable to larger molecular species. In this case internal conversion following electronic excitation produces internally "hot" ions, reducing the attachment of helium. The technique is universal because complex formation can be impeded over a wide wavelength range. [1] S. Chakrbarty, M. Holz, E. K. Campbell, A. Banerjee, D. Gerlich, and J. P. Maier, J. Phys. Chem. Lett. 2013, 4, 4051.

  18. Cold Ion Escape from the Martian Ionosphere - 2005-2014

    NASA Astrophysics Data System (ADS)

    Fränz, Markus; Dubinin, Eduard; Andrews, David; Nilsson, Hans; Fedorov, Andrei

    2015-04-01

    It has always been challenging to observe the flux of ions with energies of less than 10eV escaping from the planetary ionospheres. We here report on new measurements of the ionospheric ion flows at Mars by the ASPERA-3 experiment on board Mars Express. The ion sensor IMA of this experiment has in principle a low-energy cut-off at 10eV but in negative spacecraft charging cold ions are lifted into the range of measurement but the field of view is restricted to about 4x360 deg. In a recent paper Nilsson et al. (Earth Planets Space, 64, 135, 2012) tried to use the method of long-time averaged distribution functions to overcome these constraints. In this paper we first use the same method to show that we get results consistent with this when using ASPERA-3 observations only. But then we can show that these results are inconsistent with observations of the local plasma density by the MARSIS radar instrument on board Mars Express. We demonstrate that the method of averaged distribution function can deliver the mean flow speed of the plasma but the low-energy cut-off does usually not allow to reconstruct the density. We then combine measurements of the cold ion flow speed with the plasma density observations of MARSIS to derive the cold ion flux. In an analysis of the combined nightside datasets we show that the main escape channel is along the shadow boundary on the tailside of Mars. At a distance of about 0.5 RM the flux settles at a constant value which indicates that about half of the transterminator ionospheric flow escapes from the planet. To derive the mean escape flux we include all combined observations of ASPERA-3 and MARSIS from 2005 to 2014. Possible mechanism to generate this flux can be the ionospheric pressure gradient between dayside and nightside or momentum transfer from the solar wind via the induced magnetic field since the flow velocity is in the Alfvénic regime.

  19. Quantum Simulation of Frustrated Magnetism with Many Trapped Ions

    NASA Astrophysics Data System (ADS)

    Senko, Crystal

    2013-05-01

    A collection of trapped atomic ions is an excellent system for simulating quantum many-body physics, like magnetism, which may be difficult to access via classical computation or traditional condensed-matter experiments. Our large crystals of 10-20 ions comprise a platform to study a long-range quantum Ising model with tunable couplings in a 1D spin chain. State-dependent optical dipole forces exploit the Coulomb interaction to generate the spin-spin couplings, and fluorescence measurements on a camera are used to read out individual spin states. We investigated the spin order resulting from changing the range of antiferromagnetic interactions or the strength of an axial magnetic field, demonstrating our control over the amount of frustration present. We are turning to the study of dynamics in this system, with the aim of exploring topics including adiabaticity, spectroscopy of the Hamiltonian, the emergence of Kibble-Zurek-like behavior in a finite system, thermalization in an isolated quantum system, and nonequilibrium phase transitions. There is great promise in extending the system to 30+ spins, where computations become classically intractable. Co-authors are R. Islam, P. Richerme, W. C. Campbell, S. Korenblit, J. Smith, A. Lee, E. E. Edwards, C.-C. J. Wang, J. K. Freericks, and C. Monroe. This work is supported by grants from the U.S. Army Research Office with funding from the DARPA OLE program, IARPA, and the MURI program; and the NSF Physics Frontier Center at JQI.

  20. Quantum Simulation with 2D Arrays of Trapped Ions

    NASA Astrophysics Data System (ADS)

    Richerme, Philip

    2016-05-01

    The computational difficulty of solving fully quantum many-body spin problems is a significant obstacle to understanding the behavior of strongly correlated quantum matter. This work proposes the design and construction of a 2D quantum spin simulator to investigate the physics of frustrated materials, highly entangled states, mechanisms potentially underpinning high-temperature superconductivity, and other topics inaccessible to current 1D systems. The effective quantum spins will be encoded within the well-isolated electronic levels of trapped ions, confined in a two-dimensional planar geometry, and made to interact using phonon-mediated optical dipole forces. The system will be scalable to 100+ quantum particles, far beyond the realm of classical intractability, while maintaining individual-ion control, long quantum coherence times, and site-resolved projective spin measurements. Once constructed, the two-dimensional quantum simulator will implement a broad range of spin models on a variety of reconfigurable lattices and characterize their behavior through measurements of spin-spin correlations and entanglement. This versatile tool will serve as an important experimental resource for exploring difficult quantum many-body problems in a regime where classical methods fail.

  1. Development of a compact cold-atom atomic clock based on coherent population trapping

    NASA Astrophysics Data System (ADS)

    Blanshan, Eric M.

    Field-grade atomic clocks capable of primary standard performance in compact physics packages would be of significant value in a variety of applications ranging from network synchronization and secure communications to GPS hold-over and inertial navigation. A cold-atom coherent population trapping (CACPT) clock featuring laser-cooled atoms and pulsed Ramsey interrogation is a strong candidate for this technology if the principal frequency shifts can be controlled and the performance degradation associated with miniaturization can be overcome. In this thesis, research focused on the development of this type of compact atomic clock is presented. To address the low atom numbers obtained in small cold-atom sources, experiments were performed in which an atomic beam was decelerated with bichromatic stimulated laser forces and loaded into a mm-scale magneto-optical trap, increasing the atom number by a factor of 12.5. A CACPT clock using the high-contrast lin||lin optical interrogation technique was developed and achieved a stability of 7 x 10-13 after one hour of integration. Doppler shifts in the clock are explained using a simple kinematic model and canceled by interrogating the atoms with a counter-propagating CPT configuration. Finally, a thorough characterization of the AC-stark effect in lin||lin CPT was performed. Observed shifts are explained in terms of contributions from coherent CPT-generating couplings and population transfer effects caused by optical pumping from incoherent light. Measurements are compared with existing and new theoretical treatments, and a laser configuration is identified that reduces clock drift from light shifts to less than 10-14 for the current system.

  2. Guidelines for Designing Surface Ion Traps Using the Boundary Element Method.

    PubMed

    Hong, Seokjun; Lee, Minjae; Cheon, Hongjin; Kim, Taehyun; Cho, Dong-Il Dan

    2016-01-01

    Ion traps can provide both physical implementation of quantum information processing and direct observation of quantum systems. Recently, surface ion traps have been developed using microfabrication technologies and are considered to be a promising platform for scalable quantum devices. This paper presents detailed guidelines for designing the electrodes of surface ion traps. First, we define and explain the key specifications including trap depth, q-parameter, secular frequency, and ion height. Then, we present a numerical-simulation-based design procedure, which involves determining the basic assumptions, determining the shape and size of the chip, designing the dimensions of the radio frequency (RF) electrode, and analyzing the direct current (DC) control voltages. As an example of this design procedure, we present a case study with tutorial-like explanations. The proposed design procedure can provide a practical guideline for designing the electrodes of surface ion traps. PMID:27136559

  3. Guidelines for Designing Surface Ion Traps Using the Boundary Element Method

    PubMed Central

    Hong, Seokjun; Lee, Minjae; Cheon, Hongjin; Kim, Taehyun; Cho, Dong-il “Dan”

    2016-01-01

    Ion traps can provide both physical implementation of quantum information processing and direct observation of quantum systems. Recently, surface ion traps have been developed using microfabrication technologies and are considered to be a promising platform for scalable quantum devices. This paper presents detailed guidelines for designing the electrodes of surface ion traps. First, we define and explain the key specifications including trap depth, q-parameter, secular frequency, and ion height. Then, we present a numerical-simulation-based design procedure, which involves determining the basic assumptions, determining the shape and size of the chip, designing the dimensions of the radio frequency (RF) electrode, and analyzing the direct current (DC) control voltages. As an example of this design procedure, we present a case study with tutorial-like explanations. The proposed design procedure can provide a practical guideline for designing the electrodes of surface ion traps. PMID:27136559

  4. Control of the conformations of ion Coulomb crystals in a Penning trap

    PubMed Central

    Mavadia, Sandeep; Goodwin, Joseph F.; Stutter, Graham; Bharadia, Shailen; Crick, Daniel R.; Segal, Daniel M.; Thompson, Richard C.

    2013-01-01

    Laser-cooled atomic ions form ordered structures in radiofrequency ion traps and in Penning traps. Here we demonstrate in a Penning trap the creation and manipulation of a wide variety of ion Coulomb crystals formed from small numbers of ions. The configuration can be changed from a linear string, through intermediate geometries, to a planar structure. The transition from a linear string to a zigzag geometry is observed for the first time in a Penning trap. The conformations of the crystals are set by the applied trap potential and the laser parameters, and agree with simulations. These simulations indicate that the rotation frequency of a small crystal is mainly determined by the laser parameters, independent of the number of ions and the axial confinement strength. This system has potential applications for quantum simulation, quantum information processing and tests of fundamental physics models from quantum field theory to cosmology. PMID:24096901

  5. A monolithic array of three-dimensional ion traps fabricated with conventional semiconductor technology.

    PubMed

    Wilpers, Guido; See, Patrick; Gill, Patrick; Sinclair, Alastair G

    2012-09-01

    The coherent control of quantum-entangled states of trapped ions has led to significant advances in quantum information, quantum simulation, quantum metrology and laboratory tests of quantum mechanics and relativity. All of the basic requirements for processing quantum information with arrays of ion-based quantum bits (qubits) have been proven in principle. However, so far, no more than 14 ion-based qubits have been entangled with the ion-trap approach, so there is a clear need for arrays of ion traps that can handle a much larger number of qubits. Traps consisting of a two-dimensional electrode array have undergone significant development, but three-dimensional trap geometries can create a superior confining potential. However, existing three-dimensional approaches, as used in the most advanced experiments with trap arrays, cannot be scaled up to handle greatly increased numbers of ions. Here, we report a monolithic three-dimensional ion microtrap array etched from a silica-on-silicon wafer using conventional semiconductor fabrication technology. We have confined individual (88)Sr(+) ions and strings of up to 14 ions in a single segment of the array. We have measured motional frequencies, ion heating rates and storage times. Our results demonstrate that it should be possible to handle several tens of ion-based qubits with this approach. PMID:22820742

  6. Resonant oscillation modes of sympathetically cooled ions in a radio-frequency trap

    SciTech Connect

    Hasegawa, Taro; Shimizu, Tadao

    2002-12-01

    Sympathetic cooling of Ca{sup +}, Zn{sup +}, Sr{sup +}, Ba{sup +}, and Yb{sup +} as guest ions with laser-cooled {sup 24}Mg{sup +} as host ions in a rf ion trap is carried out, and resonant frequencies of their motion in the trap potential are measured. Various oscillation modes of the sympathetically cooled ions are observed. The resonant frequency of the oscillation mode is different from the frequency of either the collective oscillation frequency of the trapped ions or the oscillation frequency of each ion without host ions. This difference is well explained by a theoretical model in which coupled equations of motion of the host ion cloud with a single guest ion are considered.

  7. Ion collision cross section analyses in quadrupole ion traps using the filter diagonalization method: a theoretical study.

    PubMed

    Jiang, Ting; He, Miyi; Guo, Dan; Zhai, Yanbing; Xu, Wei

    2016-04-28

    Previously, we have demonstrated the feasibility of measuring ion collision cross sections (CCSs) within a quadrupole ion trap by performing time-frequency analyses of simulated ion trajectories. In this study, an improved time-frequency analysis method, the filter diagonalization method (FDM), was applied for data analyses. Using the FDM, high resolution could be achieved in both time- and frequency-domains when calculating ion time-frequency curves. Owing to this high-resolution nature, ion-neutral collision induced ion motion frequency shifts were observed, which further cause the intermodulation of ion trajectories and thus accelerate image current attenuation. Therefore, ion trap operation parameters, such as the ion number, high-order field percentage and buffer gas pressure, were optimized for ion CCS measurements. Under optimized conditions, simulation results show that a resolving power from 30 to more than 200 could be achieved for ion CCS measurements. PMID:27066889

  8. Design of a Laser Ablation Ion Source for High-Precision Penning Trap Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Hunt, Curtis; Ratnayake, Ishara; Hawks, Paul; Bryce, Richard; Redshaw, Matthew

    2014-05-01

    High-precision atomic mass measurements provide important data for a wide range of fields including atomic, nuclear and neutrino physics, determination of fundamental constants, and metrology. At Central Michigan University we are building a Penning trap system that will utilize ions produced by external ion sources to allow access to a wide range of isotopes, including long-lived radioactive isotopes and isotopes with low natural abundances. The ions will be transported to a ``capture'' trap, before being transferred to double precision-measurement trap structure. In this poster we will present the design of a laser ablation ion source and the ion extraction and transport optics. We will report on the current status of the construction and operation of the ion source and the CMU Penning trap. This work supported in part by NSF award no. 1307233.

  9. Implications of surface noise for the motional coherence of trapped ions

    NASA Astrophysics Data System (ADS)

    Talukdar, I.; Gorman, D. J.; Daniilidis, N.; Schindler, P.; Ebadi, S.; Kaufmann, H.; Zhang, T.; Häffner, H.

    2016-04-01

    Electric noise from metallic surfaces is a major obstacle towards quantum applications with trapped ions due to motional heating of the ions. Here, we discuss how the same noise source can also lead to pure dephasing of motional quantum states. The mechanism is particularly relevant at small ion-surface distances, thus imposing a constraint on trap miniaturization. By means of a free induction decay experiment, we measure the dephasing time of the motion of a single ion trapped 50 μ m above a Cu-Al surface. From the dephasing times we extract the integrated noise below the secular frequency of the ion. We find that none of the most commonly discussed surface noise models for ion traps describes both the observed heating as well as the measured dephasing satisfactorily. Thus, our measurements provide a benchmark for future models for the electric noise emitted by metallic surfaces.

  10. Quantum Information Processing with Ytterbium Ions and a Frequency Comb in a Surface Trap

    NASA Astrophysics Data System (ADS)

    Mount, Emily; Baek, So-Young; Gaultney, Daniel; Crain, Stephen; Noek, Rachel; Maunz, Peter; Kim, Jungsang

    2012-06-01

    Microfabricated surface ion traps are one of the key components for building a trapped ion quantum information processor.These multi-segmented traps are fabricated using existing silicon processing technology and can provide the fields to store a chain of ions and shuttle ions within the trap structure. Using a surface trap microfabricated by Sandia National Laboratories [1] we trap individual Yb-171 ions and demonstrate fundamental quantum information processing primitives. Low light scatter from the trap and the use of photon arrival times during fluorescence state detection enables a state detection fidelity of 98%. High fidelity rotations of the hyperfine clock state qubit have been performed using a resonant microwave field. Furthermore, we have realized single qubit rotations using Raman transitions driven by a repetition-rate stabilized frequency comb, a prerequisite for realizing motional gates with frequency combs [2]. Microelectromechanical systems (MEMS) mirrors will be used to focus Raman laser beams on individual ions in a chain to perform single qubit gates. MEMS beam steering systems can easily be scaled to multiple beams to realize two-ion gates between arbitrary ions in the chain.[4pt] [1] D Stick et al., arXiv:1008.0990v2 2010[0pt] [2] D Hayes et al., PRL 104(14)2010

  11. Experimental progress with novel surface electrode ion trap structures for quantum information processing

    NASA Astrophysics Data System (ADS)

    Clark, Craig; Blain, Matthew; Benito, Francisco; Chou, Chin-Wen; Descour, Mike; Ellis, Rob; Haltli, Ray; Heller, Edwin; Kemme, Shanalyn; Sterk, Jon; Tabakov, Boyan; Tigges, Chris; Maunz, Peter; Stick, Daniel

    2013-05-01

    Segmented surface electrode ion traps are one of the most mature platforms among candidates for scalable quantum information processing. In this poster, an overview of current results from four specific projects will be presented. Two projects involve increased light collection from trapped ion for state detection and/or remote entangling of distant ions. The first involves cavity integration into a linear surface trap, and the second, involves integration of diffractive optical elements into a linear surface trap for increased light collection. Another project involves a trap with a ring geometry which could be used to trap long chains of equally spaced ions. Finally, we report on initial testing of a trap structure with vastly improved in-plane optical access. In this structure in-plane beams can be focused to less than 8 microns while keeping a distance of at least 5 beam radii to the trap structure. Along with these projects other relevant progress from Sandia National Laboratory's ion trap group will be presented. This work was supported by Sandia's Laboratory Directed Research and Development (LDRD) and the Intelligence Advanced Research Projects Activity (IARPA). Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the US Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.

  12. Expansion Discharge Source for Ion Beam Laser Spectroscopy of Cold Molecular Ions

    NASA Astrophysics Data System (ADS)

    Porambo, Michael; Pearson, Jessica; Riccardo, Craig; McCall, Benjamin J.

    2013-06-01

    Molecular ions are important in several fields of research, and spectroscopy acts as a key tool in the study of these ions. However, problems such as low ion abundance, ion-neutral confusion, and spectral congestion due to high internal temperatures can hinder effective spectroscopic studies. To circumvent these problems, we are developing a technique called Sensitive, Cooled, Resolved, Ion BEam Spectroscopy (SCRIBES). This ion beam spectrometer will feature a continuous supersonic expansion discharge source to produce cold molecular ions, electrostatic ion optics to focus the ions into an ion beam and bend the beam away from co-produced neutral molecules, an overlap region for cavity enhanced spectroscopy, and a time-of-flight mass spectrometer. When completed, SCRIBES will be an effective tool for the study of large, fluxional, and complex molecular ions that are difficult to study with other means. The ion beam spectrometer has been successfully implemented with a hot ion source. This talk will focus on the work of integrating a supersonic expansion discharge source into the instrument. To better understand how the source would work in the whole ion beam instrument, characterization studies are being performed with spectroscopy of HN_2^+ in a section of the system to ascertain the rotational temperature of the ion expansion. Attempts are also underway to measure the ion current from a beam formed from the expansion. Once the source in this environment is properly understood, we will reintegrate it to the rest of the ion beam system, completing SCRIBES. A. A. Mills, B. M. Siller, M. W. Porambo, M. Perera, H. Kreckel and B. J. McCall J. Chem. Phys., 135, 224201, (2011). K. N. Crabtree, C. A. Kauffman and B. J. McCall Rev. Sci. Instrum. 81, 086103, (2010).

  13. Versatile cold atom target apparatus

    SciTech Connect

    Goetz, Simone; Hoeltkemeier, Bastian; Hofmann, Christoph S.; Litsch, Dominic; DePaola, Brett D.; Weidemueller, Matthias

    2012-07-15

    We report on a compact and transportable apparatus that consists of a cold atomic target at the center of a high resolution recoil ion momentum spectrometer. Cold rubidium atoms serve as a target which can be operated in three different modes: in continuous mode, consisting of a cold atom beam generated by a two-dimensional magneto-optical trap, in normal mode in which the atoms from the beam are trapped in a three-dimensional magneto-optical trap (3D MOT), and in high density mode in which the 3D MOT is operated in dark spontaneous optical trap configuration. The targets are characterized using photoionization.

  14. Ion irradiation of graphene on Ir(111): From trapping to blistering

    NASA Astrophysics Data System (ADS)

    Herbig, Charlotte; Åhlgren, E. Harriet; Valerius, Philipp; Schröder, Ulrike A.; Martínez-Galera, Antonio J.; Arman, Mohammad A.; Kotakoski, Jani; Knudsen, Jan; Krasheninnikov, Arkady V.; Michely, Thomas

    Graphene grown epitaxially on Ir(111) is irradiated with low energy noble gas ions and the processes induced by atomic collision and subsequent annealing are analyzed using scanning tunneling microscopy, low energy electron diffraction, X-ray photoelectron diffraction and thermal desorption spectroscopy. Upon room temperature ion irradiation graphene amorphizes and recovers its crystalline structure during annealing. The energetic noble gas projectiles are trapped with surprisingly high efficiency under the graphene cover up to extremely high temperatures beyond 1300K. The energy, angle, and ion species dependence of trapping are quantified. At elevated temperatures the trapped gas forms well developed and highly pressurized blisters under the graphene cover. We use molecular dynamics simulations and ab initio calculations to elucidate the trapping mechanism and its thermal robustness. Similar trapping and blistering are observed after ion irradiation of a single layer of hexagonal boron nitride on Ir(111) and we speculate on the generality of the observed phenomena.

  15. Calorimetric Low-Temperature Detectors for X-Ray Spectroscopy on Trapped Highly-Charged Heavy Ions

    NASA Technical Reports Server (NTRS)

    Kilbourne, Caroline; Kraft-Bermuth, S.; Andrianov, V.; Bleile, A.; Echler, A.; Egelhof, P.; Ilieva, S.; Kilbourne, C.; McCammon, D.

    2012-01-01

    The application of Calorimetric Low-Temperature Detectors (CLTDs) has been proposed at the Heavy-Ion TRAP facility HITRAP which is currently being installed at the Helmholtz Research Center for Heavy Ion Research GSI. This cold ion trap setup will allow the investigation of X-rays from ions practically at rest, for which the excellent energy resolution of CLTDs can be used to its full advantage. However, the relatively low intensities at HITRAP demand larger solid angles and an optimized cryogenic setup. The influence of external magnetic fields has to be taken into account. CLTDs will also be a substantial part of the instrumental equipment at the future Facility for Antiproton and Heavy Ion Research (FAIR), for which a wide variety of high-precision X-ray spectroscopy experiments has been proposed. This contribution will give an overview on the chances and challenges for the application of CLTDs at HITRAP as well as perspectives for future experiments at the FAIR facility.

  16. Experimental simulation and limitations of quantum walks with trapped ions

    NASA Astrophysics Data System (ADS)

    Matjeschk, R.; Schneider, Ch; Enderlein, M.; Huber, T.; Schmitz, H.; Glueckert, J.; Schaetz, T.

    2012-03-01

    We examine the prospects of discrete quantum walks (QWs) with trapped ions. In particular, we analyze in detail the limitations of the protocol of Travaglione and Milburn (2002 Phys. Rev. A 65 032310) that has been implemented by several experimental groups in recent years. Based on the first realization in our group (Schmitz et al 2009 Phys. Rev. Lett. 103 090504), we investigate the consequences of leaving the scope of the approximations originally made, such as the Lamb-Dicke approximation. We explain the consequential deviations from the idealized QW for different experimental realizations and an increasing number of steps by taking into account higher-order terms of the quantum evolution. It turns out that these already become significant after a few steps, which is confirmed by experimental results and is currently limiting the scalability of this approach. Finally, we propose a new scheme using short laser pulses, derived from a protocol from the field of quantum computation. We show that this scheme is not subject to the above-mentioned restrictions and analytically and numerically evaluate its limitations, based on a realistic implementation with our specific setup. Implementing the protocol with state-of-the-art techniques should allow for substantially increasing the number of steps to 100 and beyond and should be extendable to higher-dimensional QWs.

  17. Experimental system design for the integration of trapped-ion and superconducting qubit systems

    NASA Astrophysics Data System (ADS)

    De Motte, D.; Grounds, A. R.; Rehák, M.; Rodriguez Blanco, A.; Lekitsch, B.; Giri, G. S.; Neilinger, P.; Oelsner, G.; Il'ichev, E.; Grajcar, M.; Hensinger, W. K.

    2016-07-01

    We present a design for the experimental integration of ion trapping and superconducting qubit systems as a step towards the realization of a quantum hybrid system. The scheme addresses two key difficulties in realizing such a system: a combined microfabricated ion trap and superconducting qubit architecture, and the experimental infrastructure to facilitate both technologies. Developing upon work by Kielpinski et al. (Phys Rev Lett 108(13):130504, 2012. doi: 10.1103/PhysRevLett.108.130504), we describe the design, simulation and fabrication process for a microfabricated ion trap capable of coupling an ion to a superconducting microwave LC circuit with a coupling strength in the tens of kHz. We also describe existing difficulties in combining the experimental infrastructure of an ion trapping set-up into a dilution refrigerator with superconducting qubits and present solutions that can be immediately implemented using current technology.

  18. Evaporative Cooling and Coherent Axial Oscillations of Highly Charged Ions in a Penning Trap

    SciTech Connect

    Hobein, M.; Solders, A.; Suhonen, M.; Schuch, R.; Liu, Y.

    2011-01-07

    Externally, in an electron beam ion trap, generated Ar{sup 16+} ions were retrapped in a Penning trap and evaporatively cooled in their axial motion. The cooling was observed by a novel extraction technique based on the excitation of a coherent axial oscillation which yields short ion bunches of well-defined energies. The initial temperature of the ion cloud was decreased by a factor of more than 140 within 1 s, while the phase-space density of the coldest extracted ion pulses was increased by a factor of up to about 9.

  19. Ion Trap with Narrow Aperture Detection Electrodes for Fourier Transform Ion Cyclotron Resonance Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Nagornov, Konstantin O.; Kozhinov, Anton N.; Tsybin, Oleg Y.; Tsybin, Yury O.

    2015-05-01

    The current paradigm in ion trap (cell) design for Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) is the ion detection with wide aperture detection electrodes. Specifically, excitation and detection electrodes are typically 90° wide and positioned radially at a similar distance from the ICR cell axis. Here, we demonstrate that ion detection with narrow aperture detection electrodes (NADEL) positioned radially inward of the cell's axis is feasible and advantageous for FT-ICR MS. We describe design details and performance characteristics of a 10 T FT-ICR MS equipped with a NADEL ICR cell having a pair of narrow aperture (flat) detection electrodes and a pair of standard 90° excitation electrodes. Despite a smaller surface area of the detection electrodes, the sensitivity of the NADEL ICR cell is not reduced attributable to improved excite field distribution, reduced capacitance of the detection electrodes, and their closer positioning to the orbits of excited ions. The performance characteristics of the NADEL ICR cell are comparable with the state-of-the-art FT-ICR MS implementations for small molecule, peptide, protein, and petroleomics analyses. In addition, the NADEL ICR cell's design improves the flexibility of ICR cells and facilitates implementation of advanced capabilities (e.g., quadrupolar ion detection for improved mainstream applications). It also creates an intriguing opportunity for addressing the major bottleneck in FTMS—increasing its throughput via simultaneous acquisition of multiple transients or via generation of periodic non-sinusoidal transient signals.

  20. Secondary Ion Mass Spectrometry of Zeolite Materials: Observation of Abundant Aluminosilicate Oligomers Using an Ion Trap

    SciTech Connect

    Groenewold, Gary Steven; Kessinger, Glen Frank; Scott, Jill Rennee; Gianotto, Anita Kay; Appelhans, Anthony David; Delmore, James Edward

    2000-12-01

    Oligomeric oxyanions were observed in the secondary ion mass spectra (SIMS) of zeolite materials. The oxyanions have the general composition AlmSinO2(m+n)H(m-1)- (m + n = 2 to 8) and are termed dehydrates. For a given mass, multiple elemental compositions are possible because (Al + H) is an isovalent and isobaric substitute for Si. Using 18 keV Ga+ as a projectile, oligomer abundances are low relative to the monomers. Oligomer abundance can be increased by using the polyatomic projectile ReO4- (~5 keV). Oligomer abundance can be further increased using an ion trap (IT-) SIMS; in this instrument, long ion lifetimes (tens of ms) and relatively high He pressure result in significant collisional stabilization and increased high-mass abundance. The dehydrates rapidly react with adventitious H2O present in the IT-SIMS to form mono-, di-, and trihydrates. The rapidity of the reaction and comparison to aluminum oxyanion hydration suggest that H2O adds to the aluminosilicate oxyanions in a dissociative fashion, forming covalently bound product ions. In addition to these findings, it was noted that production of abundant oligomeric aluminosilicates could be significantly increased by substituting the countercation (NH4+) with the larger alkali ions Rb+ and Cs+. This constitutes a useful tactic for generating large aluminosilicate oligomers for surface characterization and ion-molecule reactivity studies.

  1. Quantum simulation of `zitterbewegung' in a single trapped ion under conditions of parity-keeping and parity-breaking

    NASA Astrophysics Data System (ADS)

    Liu, Tao; Feng, Mang; Yang, WanLi; Chen, Liang; Zhou, Fei; Wang, KeLin

    2014-07-01

    The motional trembling (`zitterbewegung') of a relativistic electron governed by Dirac equation was originally predicted by Schrödinger in the early days of quantum mechanics and simulated in a recent experiment with a single trapped ultracold ion. We investigate stable and instable confinements of a single trapped ion in a Paul trap under different conditions relevant to parity. Since our treatment involves neither restriction of Lamb-Dicke limit nor rotating-wave approximation, we may demonstrate different quantum dynamics of the single trapped ion in a wide range of the trapping parameters. We discuss the origin of the zitterbewegung which is relevant to the stability of the ion trapping.

  2. Cold Fermi gas with inverse square interaction in a harmonic trap

    NASA Astrophysics Data System (ADS)

    Kulkarni, Manas; Abanov, Alexander G.

    2011-05-01

    We study equilibrium density and spin density profiles for a model of cold one-dimensional spin 1/2 fermions interacting via inverse square interaction and exchange in an external harmonic trap. This model is the well-known spin-Calogero model (sCM) and its fully nonlinear collective field theory description is known. We extend the field theory description to the presence of an external harmonic trap and obtain analytic results for statics and dynamics of the system. For instance, we find how the equilibrium density profile changes upon tuning the interaction strength. The results we obtain for equilibrium configurations are very similar to the ones obtained recently by Ma and Yang (2010) [1] for a model of fermions with short ranged interactions. Our main approximation is the neglect of the terms of higher order in spatial derivatives in equations of motion - gradientless approximation (Kulkarni et al., 2009) [2]. Within this approximation the hydrodynamic equations of motion can be written as a set of decoupled forced Riemann-Hopf equations for the dressed Fermi momenta of the model. This enables us to write analytical solutions for the dynamics of spin and charge. We describe the time evolution of the charge density when an initial non-equilibrium profile is created by cooling the gas with an additional potential in place and then suddenly removing the potential. We present our results as a simple "single-particle" evolution in the phase space reminiscing a similar description of the dynamics of noninteracting one-dimensional fermions.

  3. Assembling a ring-shaped crystal in a microfabricated surface ion trap

    DOE PAGESBeta

    Stick, Daniel Lynn; Tabakov, Boyan; Benito, Francisco; Blain, Matthew; Clark, Craig R.; Clark, Susan; Haltli, Raymond A.; Maunz, Peter; Sterk, Jonathan D.; Tigges, Chris

    2015-09-01

    We report on experiments with a microfabricated surface trap designed for confining a chain of ions in a ring. Uniform ion separation over most of the ring is achieved with a rotationally symmetric design and by measuring and suppressing undesired electric fields. After reducing stray fields, the ions are confined primarily by a radio-frequency pseudopotential and their mutual Coulomb repulsion. As a result, approximately 400 40Ca+ ions with an average separation of 9 μm comprise the ion crystal.

  4. The JPL Hg(sup +) Extended Linear Ion Trap Frequency Standard: Status, Stability, and Accuracy Prospects

    NASA Technical Reports Server (NTRS)

    Tjoelker, R. L.; Prestage, J. D.; Maleki, L.

    1996-01-01

    Microwave frequency standards based on room temperature (sup 199)Hg(sup +) ions in a Linear Ion Trap (LITS) presently achieve a Signal to Noise and line Q inferred short frequency stability. Long term stability has been measured for averaging intervals up to 5 months with apparent sensitivity to variations in ion number/temperature limiting the flicker floor.

  5. Production of Ar{sup q+} ions with a tandem linear Paul trap

    SciTech Connect

    Higaki, H. Nagayasu, K.; Iwai, T.; Ito, K.; Okamoto, H.

    2015-06-29

    A tandem linear Paul trap was used to create highly charged Argon ions by electron impact ionizations. By improving the operation scheme, the production of Ar{sup 4+} ions was confirmed. Possible improvements for the future experiments with laser cooled Ca{sup +} ions are suggested.

  6. Experimental study on dipole motion of an ion plasma confined in a linear Paul trap

    NASA Astrophysics Data System (ADS)

    Ito, K.; Okano, T.; Moriya, K.; Fukushima, K.; Higaki, H.; Okamoto, H.

    2015-11-01

    The compact non-neutral plasma trap systems named "S-POD" have been developed at Hiroshima University as an experimental simulator of beam dynamics. S-POD is based either on a linear Paul trap or on a Penning trap and can approximately reproduce the collective motion of a relativistic charged-particle beam observed in the center-of-mass frame. We here employ the Paul trap system to investigate the behavior of an ion plasma near a dipole resonance. A simple method is proposed to calibrate the data of secular frequency measurements by using the dipole instability condition. We also show that the transverse density profile of an ion plasma in the trap can be estimated from the time evolution of ion losses caused by the resonance.

  7. Ion/molecule reactions performed in a miniature cylindrical ion trap mass spectrometer.

    PubMed

    Riter, Leah S; Meurer, Eduardo C; Handberg, Eric S; Laughlin, Brian C; Chen, Hao; Patterson, Garth E; Eberlin, Marcos N; Cooks, R Graham

    2003-09-01

    A recently constructed miniature mass spectrometer, based on a cylindrical ion trap (CIT) mass analyzer, is used to perform ion/molecule reactions in order to improve selectivity for in situ analysis of explosives and chemical warfare agent simulants. Six different reactions are explored, including several of the Eberlin reaction type (M. N. Eberlin and R. G. Cooks, Org. Mass Spectrom., 1993, 28, 679-687) as well as novel gas-phase Meerwein reactions. The reactions include (1) Eberlin transacetalization of the benzoyl, 2,2-dimethyloximinium, and 2,2-dimethylthiooximinium cations with 2,2-dimethyl-1,3-dioxolane to form 2-phenyl-1,3-dioxolanylium cations, 2,2-dimethylamine-1,3-dioxolanylium cations and the 2,2-dimethylamin-1,3-oxathiolanylium cations, respectively; (2) Eberlin reaction of the phosphonium ion CH3P(O)OCH3+, formed from the chemical warfare agent simulant dimethyl methylphosphonate (DMMP), with 1,4-dioxane to yield the 1,3,2-dioxaphospholanium ion, a new characteristic reaction for phosphate ester detection; (3) the novel Meerwein reaction of the ion CH3P(O)OCH3+ with propylene sulfide forming 1,3,2-oxathionylphospholanium ion; (4) the Meerwein reaction of the benzoyl cation with propylene oxide and propylene sulfide to form 4-methyl-2-phenyl-1,3-dioxolane and its thio analog, respectively; (5) ketalization of the benzoyl cation with ethylene glycol to form the 2-phenyl-1,3-dioxolanylium cation; (6) addition/NO2 elimination involving benzonitrile radical cation in reaction with nitrobenzene to form an arylated nitrile, a diagnostic reaction for explosives detection and (7) simple methanol addition to the C7H7+ ion, formed by NO2 loss from the molecular ion of p-nitrotoluene to form an intact adduct. Evidence is provided that these reactions occur to give the products described and their potential analytical utility is discussed. PMID:14529016

  8. Ion-neutral chemistry at ultralow energies:Dynamics of reactive collisions between laser-cooled Ca+ or Ba+ ions and Rb atoms in an ion-atom hybrid trap

    NASA Astrophysics Data System (ADS)

    Dulieu, O.; Hall, F. H. J.; Eberle, P.; Hegi, G.; Raoult, M.; Aymar, M.; Willitsch, S.

    2013-05-01

    Cold chemical reactions between laser-cooled Ca+ or Ba+ ions and Rb atoms were studied in an ion-atom hybrid trap. Reaction rate constants were determined in the collision energy range Ecoll /kB = 20 mK-20 K. Product branching ratios were studied using resonant-excitation mass spectrometry. The dynamics of the reactive processes including the radiative formation of CaRb+ and BaRb+ molecular ions has been analyzed using accurate potential energy curves and quantum-scattering calculations for the radiative channels. It is shown that the energy dependence of the reaction rates is governed by long-range interactions, while its magnitude is determined by short-range non-adiabatic and radiative couplings. The quantum character of the collisions is predicted to manifest itself in the occurrence of narrow shape resonances at well-defined collision energies. The present results highlight both universal and system-specific phenomena in cold ion-neutral collisions. This work was supported by the Swiss National Science Foundation and the COST Action ''Ion Traps for Tomorrow's Applications''.

  9. Laboratory Astrophysics Using the Electron Beam Ion Trap

    NASA Astrophysics Data System (ADS)

    Brown, Gregory V.

    2014-06-01

    X-ray astronomy has seen profound growth in discovery space for over a decade resulting almost entirely from the successful operation of three X-ray observatories: Chandra, XMM-Newton, and Suzaku. The high sensitivity, high resolution instrumentation on these satellites have provided the X-ray astrophysicists with relatively straightforward access to powerful line diagnostics that tightly constrain the physical parameters of celestial sources. For example, accurate measurements of transition energies, line shapes, and intensities provide quantitative measures of a velocity fields, electron densities and temperatures. X-ray measurements probe sources unattainable by any other wavelength bands, such as the regions of accretion disks near black holes, and the hot intracluster medium in clusters of galaxies. Thus, X-ray astronomy in the age of Chandra, XMM-Newton, and Suzaku provides important pieces of the puzzles necessary to understand the formation and evolution of galaxies, stars, the phenomena near black holes, and the evolution of the universe as a whole. Unfortunately, accurate unambiguous interpretation of high quality spectra is often limited by the accuracy and completeness of atomic data rather than the uncertainties related to counting statistics or instrumentation. Starting over twenty years ago, the electron beam ion trap facility at Lawrence Livermore National Laboratory has been used to benchmark spectral models used to interpret celestial data, and to address specific problems facing the astrophysics community. More recently, the portable FLASH-EBIT, built and maintained at the Max Planck Institute for Nuclear Physics, Heidelberg and coupled to third and fourth generation light sources has opened new measurement regimes relavant to the high energy astrophysics community. Selected results will be presented. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344

  10. Generation of a cold pulsed beam of Rb atoms by transfer from a 3D magneto-optic trap

    NASA Astrophysics Data System (ADS)

    Chanu, Sapam Ranjita; Rathod, Ketan D.; Natarajan, Vasant

    2016-08-01

    We demonstrate a technique for producing a cold pulsed beam of atoms by transferring a cloud of atoms trapped in a three dimensional magneto-optic trap (MOT). The MOT is loaded by heating a getter source of Rb atoms. We show that it is advantageous to transfer with two beams (with a small angle between them) compared to a single beam, because the atoms stop interacting with the beams in the two-beam technique, which results in a Gaussian velocity distribution. The atoms are further cooled in optical molasses by turning off the MOT magnetic field before the transfer beams are turned on.

  11. Miniaturized gas chromatograph-Paul ion trap system: applications to environmental monitoring

    NASA Technical Reports Server (NTRS)

    Shortt, B. J.; Darrach, M. R.; Holland, Paul M.; Chutjian, A.

    2004-01-01

    A miniature gas chromatograph (GC) and miniature Paul ion trap (PT) mass spectrometer system has been developed for identifying and quantifying chemical species present in closed environments having a complex mixture of gases.

  12. in situ plasma removal of surface contaminants from ion trap electrodes

    SciTech Connect

    Haltli, Raymond A.

    2015-04-01

    This research resulted in a construction and implementation of an in situ plasma discharge to remove surface contaminants from electrodes in an ion trapping experimental system is presented with results.

  13. Measurement of ion motional heating rates over a range of trap frequencies and temperatures

    NASA Astrophysics Data System (ADS)

    Bruzewicz, C. D.; Sage, J. M.; Chiaverini, J.

    2015-04-01

    We present measurements of the motional heating rate of a trapped ion at different trap frequencies and temperatures between ˜0.6 and 1.5 MHz and ˜4 and 295 K. Additionally, we examine the possible effect of adsorbed surface contaminants with boiling points below ˜105 ∘C by measuring the ion heating rate before and after locally baking our ion trap chip under ultrahigh vacuum conditions. We compare the heating rates presented here to those calculated from available electric-field noise models. We can tightly constrain a subset of these models based on their expected frequency and temperature scaling interdependence. Discrepancies between the measured results and predicted values point to the need for refinement of theoretical noise models in order to more fully understand the mechanisms behind motional trapped-ion heating.

  14. Cascade emission in electron beam ion trap plasma of W25+ ion

    NASA Astrophysics Data System (ADS)

    Jonauskas, V.; Pütterich, T.; Kučas, S.; Masys, Š.; Kynienė, A.; Gaigalas, G.; Kisielius, R.; Radžiūtė, L.; Rynkun, P.; Merkelis, G.

    2015-07-01

    Spectra of the W25+ ion are studied using the collisional-radiative model (CRM) with an ensuing cascade emission. It is determined that the cascade emission boosts intensities only of a few lines in the 10-30 nm range. The cascade emission is responsible for the disappearance of structure of lines at about 6 nm in the electron beam ion trap plasma. Emission band at 4.5-5.3 nm is also affected by the cascade emission. The strongest lines in the CRM spectrum correspond to 4d9 4f4 → 4f3 transitions, while 4f2 5 d → 4f3 transitions arise after the cascade emission is taken into account.

  15. Universal quantum computation in decoherence-free subspaces with hot trapped ions

    SciTech Connect

    Aolita, Leandro; Davidovich, Luiz; Kim, Kihwan; Haeffner, Hartmut

    2007-05-15

    We consider interactions that generate a universal set of quantum gates on logical qubits encoded in a collective-dephasing-free subspace, and discuss their implementations with trapped ions. This allows for the removal of the by-far largest source of decoherence in current trapped-ion experiments, collective dephasing. In addition, an explicit parametrization of all two-body Hamiltonians able to generate such gates without the system's state ever exiting the protected subspace is provided.

  16. Instability due to trapped electrons in magnetized multi-ion dusty plasmas

    NASA Astrophysics Data System (ADS)

    Haider, M. M.; Ferdous, T.; Duha, S. S.

    2015-05-01

    An attempt has been made to find out the effects of trapped electrons in dust-ion-acoustic solitary waves in magnetized multi-ion plasmas, as in most space plasmas, the hot electrons follow the trapped/vortex-like distribution. To do so, we have derived modified Zakharov-Kuznetsov equation using reductive perturbation method and its solution. A small- perturbation technique was employed to find out the instability criterion and growth rate of such a wave.

  17. TrapCAD — a tool to design and study magnetic traps of ECR ion sources

    NASA Astrophysics Data System (ADS)

    Vámosi, J.; Biri, S.

    1994-11-01

    To design the magnetic system of the Debrecen-ECRIS and to study the behaviour of charged particle traps a graphical computer code (TrapCAD 1.0) was developed. This code uses the outputs of popular general-purpose magnetic field calculation codes (e.g. POISSON/PANDIRA) as input. The TrapCAD offers several built-in functions: draws field lines, flux tubes and the surfaces of equal magnetic field. It is also possible to calculate and visualise the one-particle movement of charged particles in the trap. This paper describes all the details of the code implementation, features and functions. Examples for the optimization of the Debrecen-ECRIS — to reduce the price of the hexapole magnet and the electrical consumption of the solenoids — are also given.

  18. Microfabrication of Surface Ion Trap Chip and State Manipulation of Single 171Yb+ Qubit

    NASA Astrophysics Data System (ADS)

    Hong, Seokjun; Lee, Minjae; Cheon, Hongjin; Ahn, Jun Sik; Kim, Taehyun; Cho, Dong-Il ``Dan''; ASRI/ISRC; Department of Electrical; Computer Engineering, Seoul National University Team; Quantum Tech. Lab., SK Telecom Team

    2015-05-01

    Ion traps are one of the promising physical implementations of quantum information processing. This paper presents new ion trap chips using a copper sacrificial layer. Boundary element method (BEM) simulation results show that the fabricated ion trap chip has a trap depth of 0.063 eV at 81 um above the top electrodes and radial secular frequencies of 1.52 and 1.6 MHz. Up to six 174Yb+ ions and three 171Yb+ ions have been successfully trapped. This paper also demonstrates the state manipulation of single 171Yb+ qubit through Rabi oscillation induced by microwave with frequency of 12.628 GHz. Using the new copper sacrificial method, accurate overhang dimensions that can effectively shield stray electric fields from dielectric layers, which in turn can reduce the micromotion of trapped ions, can be achieved. Acknowledgement: This work was partially supported by ICT R&D program of MSIP/IITP. [10043464, Development of quantum repeater technology for the application to communication systems].

  19. Novel sampling methods for use with thermal desorption ion trap mass spectrometry

    SciTech Connect

    Barshick, S.A.; Buchanan, M.V.

    1994-12-31

    Novel sampling approaches have been investigated to improve the analytical utility of thermal desorption Direct Sampling Ion Trap Mass Spectrometry (DSITMS). Because DSITMS involves the direct introduction of samples into an ion trap mass spectrometer, problems with detection capabilities (sensitivity and selectivity) can often occur when performing trace analysis in complex matrices. Various sampling approaches have been evaluated to improve thermal desorption detection capabilities and to extend the utilities of DSITMS methodologies without significantly increasing analysis times or the cost-effectiveness of DSITMS methods. Three sampling approaches have been investigated including solid phase microextraction (SPME), solid phase extraction columns (SPEC), and purge and trap.

  20. The laser ion source trap for highest isobaric selectivity in online exotic isotope productiona)

    NASA Astrophysics Data System (ADS)

    Schwellnus, F.; Blaum, K.; Catherall, R.; Crepieux, B.; Fedosseev, V.; Gottwald, T.; Kluge, H.-J.; Marsh, B.; Mattolat, C.; Rothe, S.; Stora, T.; Wendt, K.

    2010-02-01

    The improvement in the performance of a conventional laser ion source in the laser ion source and trap (LIST) project is presented, which envisages installation of a repeller electrode and a linear Paul trap/ion guide structure. This approach promises highest isobaric purity and optimum temporal and spatial control of the radioactive ion beam produced at an online isotope separator facility. The functionality of the LIST was explored at the offline test separators of University of Mainz (UMz) and ISOLDE/CERN, using the UMz solid state laser system. Ionization efficiency and selectivity as well as time structure and transversal emittance of the produced ion beam was determined. Next step after complete characterization is the construction and installation of the radiation-hard final trap structure and its first online application.

  1. The laser ion source trap for highest isobaric selectivity in online exotic isotope production.

    PubMed

    Schwellnus, F; Blaum, K; Catherall, R; Crepieux, B; Fedosseev, V; Gottwald, T; Kluge, H-J; Marsh, B; Mattolat, C; Rothe, S; Stora, T; Wendt, K

    2010-02-01

    The improvement in the performance of a conventional laser ion source in the laser ion source and trap (LIST) project is presented, which envisages installation of a repeller electrode and a linear Paul trap/ion guide structure. This approach promises highest isobaric purity and optimum temporal and spatial control of the radioactive ion beam produced at an online isotope separator facility. The functionality of the LIST was explored at the offline test separators of University of Mainz (UMz) and ISOLDE/CERN, using the UMz solid state laser system. Ionization efficiency and selectivity as well as time structure and transversal emittance of the produced ion beam was determined. Next step after complete characterization is the construction and installation of the radiation-hard final trap structure and its first online application. PMID:20192370

  2. Advances in ion trap mass spectrometry: Photodissociation as a tool for structural elucidation

    SciTech Connect

    Stephenson, J.L. Jr.; Booth, M.M.; Eyler, J.R.; Yost, R.A.

    1995-12-01

    Photo-induced dissociation (PID) is the next most frequently used method (after collisional activation) for activation of Polyatomic ions in tandem mass spectrometry. The range of internal energies present after the photon absorption process are much narrower than those obtained with collisional energy transfer. Therefore, the usefulness of PID for the study of ion structures is greatly enhanced. The long storage times and instrumental configuration of the ion trap mass spectrometer are ideally suited for photodissociation experiments. This presentation will focus on both the fundamental and analytical applications of CO{sub 2} lasers in conjunction with ion trap mass spectrometry. The first portion of this talk will examine the fundamental issues of wavelength dependence, chemical kinetics, photoabsorption cross section, and collisional effects on photodissociation efficiency. The second half of this presentation will look at novel instrumentation for electrospray/ion trap mass spectrometry, with the concurrent development of photodissociation as a tool for structural elucidation of organic compounds and antibiotics.

  3. A gyro-kinetic model for trapped electron and ion modes

    NASA Astrophysics Data System (ADS)

    Drouot, Thomas; Gravier, Etienne; Reveille, Thierry; Ghizzo, Alain; Bertrand, Pierre; Garbet, Xavier; Sarazin, Yanick; Cartier-Michaud, Thomas

    2014-10-01

    In tokamak plasmas, it is recognized that ITG (ion temperature gradient instability) and trapped electron modes (TEM) are held responsible for turbulence giving rise to anomalous transport. The present work focuses on the building of a model including trapped kinetic ions and trapped kinetic electrons. For this purpose, the dimensionality is reduced by averaging the motion over the cyclotron motion and the "banana" orbits, according to the fact that the instabilities are characterized by frequencies of the order of the low trapped particle precession frequency. Moreover, a set of action-angle variables is used. The final model is 4D (two-dimensional phase space parametrized by the two first adiabatic invariants namely the particle energy and the trapping parameter). In this paper, the trapped ion and electron modes (TIM and TEM) are studied by using a linear analysis of the model. This work is currently performed in order to include trapped electrons in an existing semi lagrangian code for which TIM modes are already taken into account. This study can be considered as a first step in order to include kinetic trapped electrons in the 5D gyrokinetic code GYSELA [J. Abiteboul et al., ESAIM Proc. 32, 103 (2011)]. Contribution to the Topical Issue "Theory and Applications of the Vlasov Equation", edited by Francesco Pegoraro, Francesco Califano, Giovanni Manfredi and Philip J. Morrison.

  4. Computer Modeling of an Ion Trap Mass Analyzer, Part I: Low Pressure Regime

    NASA Astrophysics Data System (ADS)

    Nikolić, Dragan; Madzunkov, Stojan M.; Darrach, Murray R.

    2015-12-01

    We present the multi-particle simulation program suite Computational Ion Trap Analyzer (CITA) designed to calculate the ion trajectories within a Paul quadrupole ion trap developed by the Jet Propulsion Laboratory (JPL). CITA uses an analytical expression of the electrodynamic field, employing up to six terms in multipole expansion and a modified velocity-Verlet method to numerically calculate ion trajectories. The computer code is multithreaded and designed to run on shared-memory architectures. CITA yields near real-time simulations with full propagation of 26 particles per second per core. As a consequence, a realistic numbers of trapped ions (100+ million) can be used and their trajectories modeled, yielding a representative prediction of mass spectrometer analysis of trace gas species. When the model is compared with experimental results conducted at low pressures using the conventional quadrupole and dipole excitation modes, there is an excellent agreement with the observed peak shapes. Owing to the program's efficiency, CITA has been used to explore regions of trapping stability that are of interest to experimental research. These results are expected to facilitate a fast and reliable modeling of ion dynamics in miniature quadrupole ion trap and improve the interpretation of observed mass spectra.

  5. Multiple Mass Analysis Using an Ion Trap Array (ITA) Mass Analyzer

    NASA Astrophysics Data System (ADS)

    Xiao, Yu; Chu, Yanqiu; Ling, Xing; Ding, Zhengzhi; Xu, Chongsheng; Ding, Li; Ding, Chuan-Fan

    2013-09-01

    A novel ion trap array (ITA) mass analyzer with six ion trapping and analyzing channels was investigated. It is capable of analyzing multiple samples simultaneously. The ITA was built with several planar electrodes made of stainless steel and 12 identical parallel zirconia ceramic substrates plated with conductive metal layers. Each two of the opposing ceramic electrode plates formed a boundary of an ion trap channel and six identical ion trapping and analyzing channels were placed in parallel without physical electrode between any two adjacent channels. The electric field distribution inside each channel was studied with simulation. The new design took the advantage of high precision machining attributable to the rigidity of ceramic, and the convenience of surface patterning technique. The ITA system was tested by using a two-channel electrospray ionization source, a multichannel simultaneous quadruple ion guide, and two detectors. The simultaneous analysis of two different samples with two adjacent ITA channels was achieved and independent mass spectra were obtained. For each channel, the mass resolution was tested. Additional ion trap functions such as mass-selected ion isolation and collision-induced dissociation (CID) were also tested. The results show that one ITA is well suited for multiple simultaneous mass analyses.

  6. Multiple mass analysis using an ion trap array (ITA) mass analyzer.

    PubMed

    Yu, Xiao; Chu, Yanqiu; Ling, Xing; Ding, Zhengzhi; Xu, Chongsheng; Ding, Li; Ding, Chuan-Fan

    2013-09-01

    A novel ion trap array (ITA) mass analyzer with six ion trapping and analyzing channels was investigated. It is capable of analyzing multiple samples simultaneously. The ITA was built with several planar electrodes made of stainless steel and 12 identical parallel zirconia ceramic substrates plated with conductive metal layers. Each two of the opposing ceramic electrode plates formed a boundary of an ion trap channel and six identical ion trapping and analyzing channels were placed in parallel without physical electrode between any two adjacent channels. The electric field distribution inside each channel was studied with simulation. The new design took the advantage of high precision machining attributable to the rigidity of ceramic, and the convenience of surface patterning technique. The ITA system was tested by using a two-channel electrospray ionization source, a multichannel simultaneous quadruple ion guide, and two detectors. The simultaneous analysis of two different samples with two adjacent ITA channels was achieved and independent mass spectra were obtained. For each channel, the mass resolution was tested. Additional ion trap functions such as mass-selected ion isolation and collision-induced dissociation (CID) were also tested. The results show that one ITA is well suited for multiple simultaneous mass analyses. PMID:23797864

  7. Computer Modeling of an Ion Trap Mass Analyzer, Part I: Low Pressure Regime.

    PubMed

    Nikolić, Dragan; Madzunkov, Stojan M; Darrach, Murray R

    2015-12-01

    We present the multi-particle simulation program suite Computational Ion Trap Analyzer (CITA) designed to calculate the ion trajectories within a Paul quadrupole ion trap developed by the Jet Propulsion Laboratory (JPL). CITA uses an analytical expression of the electrodynamic field, employing up to six terms in multipole expansion and a modified velocity-Verlet method to numerically calculate ion trajectories. The computer code is multithreaded and designed to run on shared-memory architectures. CITA yields near real-time simulations with full propagation of 26 particles per second per core. As a consequence, a realistic numbers of trapped ions (100+ million) can be used and their trajectories modeled, yielding a representative prediction of mass spectrometer analysis of trace gas species. When the model is compared with experimental results conducted at low pressures using the conventional quadrupole and dipole excitation modes, there is an excellent agreement with the observed peak shapes. Owing to the program's efficiency, CITA has been used to explore regions of trapping stability that are of interest to experimental research. These results are expected to facilitate a fast and reliable modeling of ion dynamics in miniature quadrupole ion trap and improve the interpretation of observed mass spectra. Graphical Abstract ᅟ. PMID:26286456

  8. Optimizing the Stark-decelerator beamline for the trapping of cold molecules using evolutionary strategies

    SciTech Connect

    Gilijamse, Joop J.; Kuepper, Jochen; Hoekstra, Steven; Vanhaecke, Nicolas; Meerakker, Sebastiaan Y. T. van de; Meijer, Gerard

    2006-06-15

    We demonstrate feedback control optimization for the Stark deceleration and trapping of neutral polar molecules using evolutionary strategies. In a Stark-decelerator beamline, pulsed electric fields are used to decelerate OH radicals and subsequently store them in an electrostatic trap. The efficiency of the deceleration and trapping process is determined by the exact timings of the applied electric field pulses. Automated optimization of these timings yields an increase of 40% of the number of trapped OH radicals.

  9. High-Fidelity Two-Qubit Gates in a Surface Ion Trap

    NASA Astrophysics Data System (ADS)

    Lobser, Daniel; Blain, Matthew; Blume-Kohout, Robin; Fortier, Kevin; Mizrahi, Jonathan; Nielsen, Erik; Rudinger, Kenneth; Sterk, Jonathan; Stick, Daniel; Maunz, Peter

    2016-05-01

    Microfabricated surface traps are capable of supporting a variety of exotic trapping geometries and provide a scalable system for trapped ion Quantum Information Processing (QIP). However, the feasibility of using surface traps for QIP has long been a point of contention because the close proximity of the ions to trap electrodes increases heating rates and might lead to laser-induced charging of the trap. As surface traps continue to evolve at a remarkable rate, their performance is rapidly approaching that of macroscopic electrode traps. Using Sandia's High-Optical-Access surface trap, we demonstrate robust single-qubit gates, both laser- and microwave-based. Our gates are accurately characterized by Gate Set Tomography (GST) and we report the first diamond norm measurements near the fault-tolerance threshold. Extending these techniques, we've realized a Mølmer-Sørensen two-qubit gate that is stable for several hours. This stability has allowed us to perform the first GST measurements of a two-qubit gate, yielding a process fidelity of 99.58(6)%. This work was supported by the Laboratory Directed Research and Development (LDRD) program at Sandia National Laboratories.

  10. Experimental Characterization of Secular Frequency Scanning in Ion Trap Mass Spectrometers

    NASA Astrophysics Data System (ADS)

    Snyder, Dalton T.; Pulliam, Christopher J.; Wiley, Joshua S.; Duncan, Jason; Cooks, R. Graham

    2016-07-01

    Secular frequency scanning is implemented and characterized using both a benchtop linear ion trap and a miniature rectilinear ion trap mass spectrometer. Separation of tetraalkylammonium ions and those from a mass calibration mixture and from a pesticide mixture is demonstrated with peak widths approaching unit resolution for optimized conditions using the benchtop ion trap. The effects on the spectra of ion trap operating parameters, including waveform amplitude, scan direction, scan rate, and pressure are explored, and peaks at black holes corresponding to nonlinear (higher-order field) resonance points are investigated. Reverse frequency sweeps (increasing mass) on the Mini 12 are shown to result in significantly higher ion ejection efficiency and superior resolution than forward frequency sweeps that decrement mass. This result is accounted for by the asymmetry in ion energy absorption profiles as a function of AC frequency and the shift in ion secular frequency at higher amplitudes in the trap due to higher order fields. We also found that use of higher AC amplitudes in forward frequency sweeps biases ions toward ejection at points of higher order parametric resonance, despite using only dipolar excitation. Higher AC amplitudes also increase peak width and decrease sensitivity in both forward and reverse frequency sweeps. Higher sensitivity and resolution were obtained at higher trap pressures in the secular frequency scan, in contrast to conventional resonance ejection scans, which showed the opposite trend in resolution on the Mini 12. Mass range is shown to be naturally extended in secular frequency scanning when ejecting ions by sweeping the AC waveform through low frequencies, a method which is similar, but arguably superior, to the more usual method of mass range extension using low q resonance ejection.

  11. Experimental Characterization of Secular Frequency Scanning in Ion Trap Mass Spectrometers

    NASA Astrophysics Data System (ADS)

    Snyder, Dalton T.; Pulliam, Christopher J.; Wiley, Joshua S.; Duncan, Jason; Cooks, R. Graham

    2016-03-01

    Secular frequency scanning is implemented and characterized using both a benchtop linear ion trap and a miniature rectilinear ion trap mass spectrometer. Separation of tetraalkylammonium ions and those from a mass calibration mixture and from a pesticide mixture is demonstrated with peak widths approaching unit resolution for optimized conditions using the benchtop ion trap. The effects on the spectra of ion trap operating parameters, including waveform amplitude, scan direction, scan rate, and pressure are explored, and peaks at black holes corresponding to nonlinear (higher-order field) resonance points are investigated. Reverse frequency sweeps (increasing mass) on the Mini 12 are shown to result in significantly higher ion ejection efficiency and superior resolution than forward frequency sweeps that decrement mass. This result is accounted for by the asymmetry in ion energy absorption profiles as a function of AC frequency and the shift in ion secular frequency at higher amplitudes in the trap due to higher order fields. We also found that use of higher AC amplitudes in forward frequency sweeps biases ions toward ejection at points of higher order parametric resonance, despite using only dipolar excitation. Higher AC amplitudes also increase peak width and decrease sensitivity in both forward and reverse frequency sweeps. Higher sensitivity and resolution were obtained at higher trap pressures in the secular frequency scan, in contrast to conventional resonance ejection scans, which showed the opposite trend in resolution on the Mini 12. Mass range is shown to be naturally extended in secular frequency scanning when ejecting ions by sweeping the AC waveform through low frequencies, a method which is similar, but arguably superior, to the more usual method of mass range extension using low q resonance ejection.

  12. Experimental Characterization of Secular Frequency Scanning in Ion Trap Mass Spectrometers.

    PubMed

    Snyder, Dalton T; Pulliam, Christopher J; Wiley, Joshua S; Duncan, Jason; Cooks, R Graham

    2016-07-01

    Secular frequency scanning is implemented and characterized using both a benchtop linear ion trap and a miniature rectilinear ion trap mass spectrometer. Separation of tetraalkylammonium ions and those from a mass calibration mixture and from a pesticide mixture is demonstrated with peak widths approaching unit resolution for optimized conditions using the benchtop ion trap. The effects on the spectra of ion trap operating parameters, including waveform amplitude, scan direction, scan rate, and pressure are explored, and peaks at black holes corresponding to nonlinear (higher-order field) resonance points are investigated. Reverse frequency sweeps (increasing mass) on the Mini 12 are shown to result in significantly higher ion ejection efficiency and superior resolution than forward frequency sweeps that decrement mass. This result is accounted for by the asymmetry in ion energy absorption profiles as a function of AC frequency and the shift in ion secular frequency at higher amplitudes in the trap due to higher order fields. We also found that use of higher AC amplitudes in forward frequency sweeps biases ions toward ejection at points of higher order parametric resonance, despite using only dipolar excitation. Higher AC amplitudes also increase peak width and decrease sensitivity in both forward and reverse frequency sweeps. Higher sensitivity and resolution were obtained at higher trap pressures in the secular frequency scan, in contrast to conventional resonance ejection scans, which showed the opposite trend in resolution on the Mini 12. Mass range is shown to be naturally extended in secular frequency scanning when ejecting ions by sweeping the AC waveform through low frequencies, a method which is similar, but arguably superior, to the more usual method of mass range extension using low q resonance ejection. Graphical Abstract ᅟ. PMID:27032650

  13. A quadrupole ion trap with cylindrical geometry operated in the mass-selective instability mode.

    PubMed

    Wells, J M; Badman, E R; Cooks, R G

    1998-02-01

    A cylindrical geometry ion trap is used to record mass spectra in the mass-selective instability mode. The geometry of the cylindrical ion trap has been optimized to maximize the quadrupole field component relative to the higher-order field content through field calculations using the Poisson/Superfish code and through experimental variation of the electrode structure. The results correspond well with predictions of the calculations. The trap has been used to record mass spectra with better than unit mass resolution, high sensitivity, and a mass/charge range of ∼600 Th. Multistage (MS(3)) experiments have been performed, and the Mathieu stability region has been experimentally mapped. The performance of this device compares satisfactorily with that of the hyperbolic ion trap. PMID:21644742

  14. Systematics in a measurement of the electron's electric dipole moment using trapped molecular ions

    NASA Astrophysics Data System (ADS)

    Grau, Matt; Cossel, Kevin; Cairncross, William; Gresh, Dan; Zhou, Yan; Ye, Jun; Cornell, Eric

    2015-05-01

    A precision measurement of the electron's electric dipole moment (EDM) has important implications for physics beyond the Standard Model. Trapped molecular ions offer high sensitivity in such an experiment because of the large effective electric fields and long coherence times that are possible. Our experiment uses Ramsey spectroscopy of HfF+ ions in a linear RF trap with rotating bias fields, achieving coherence times beyond 1 second for 1000 trapped ions. Compared to other electron EDM experiments that use molecular beams, we will be sensitive to a different class of systematic errors. In this work we investigate systematic errors arising from all fields involved in the experiment, including the trapping and polarizing electric fields, magnetic field gradients, and motional effects such as geometric phases. This work was supported by NIST and NSF.

  15. Reduction of trapped-ion anomalous heating by in situ surface plasma cleaning

    NASA Astrophysics Data System (ADS)

    McConnell, Robert; Bruzewicz, Colin; Chiaverini, John; Sage, Jeremy

    2015-08-01

    Anomalous motional heating is a major obstacle to scalable quantum information processing with trapped ions. Although the source of this heating is not yet understood, several previous studies suggest that noise due to surface contaminants is the limiting heating mechanism in some instances. We demonstrate an improvement by a factor of 4 in the room-temperature heating rate of a niobium surface electrode trap by in situ plasma cleaning of the trap surface. This surface treatment was performed with a simple homebuilt coil assembly and commercially available matching network and is considerably gentler than other treatments, such as ion milling or laser cleaning, that have previously been shown to improve ion heating rates. We do not see an improvement in the heating rate when the trap is operated at cryogenic temperatures, pointing to a role of thermally activated surface contaminants in motional heating whose activity may freeze out at low temperatures.

  16. Quantum control and simulation with 2-dimensional arrays of trapped ions

    NASA Astrophysics Data System (ADS)

    Britton, J. W.; Sawyer, B. C.; Bohnet, J. G.; Bollinger, J. J.; Keith, A. C.; Meiser, D.

    2014-05-01

    Trapped ions, when cooled to sufficiently low temperatures form crystalline arrays. We describe our efforts to extend the quantum control techniques developed with small linear chains of ions in rf traps to larger two-dimensional crystals of hundreds of ions formed in a Penning trap. Our qubit is the 124 GHz electron spin-flip transition in the ground state of Be+ in the 4.5 T magnetic field of the Penning trap. We control the spins with an effective transverse magnetic field generated with 124 GHz microwaves. Spin-dependent optical dipole forces (ODF) are used to engineer long range Ising interactions between the ion qubits and to characterize the motional degrees of freedom of the trapped ions. We will discuss the design and implementation of a new Penning trap that employs an m=3 rotating wall and enables the application of an ODF with lower spontaneous emission. We will also discuss simulation work that provides information on the temperature of the in-plane modes. Support from NIST and the DARPA-OLE program.

  17. Analysis of thermal radiation in ion traps for optical frequency standards

    NASA Astrophysics Data System (ADS)

    Doležal, M.; Balling, P.; Nisbet-Jones, P. B. R.; King, S. A.; Jones, J. M.; Klein, H. A.; Gill, P.; Lindvall, T.; Wallin, A. E.; Merimaa, M.; Tamm, C.; Sanner, C.; Huntemann, N.; Scharnhorst, N.; Leroux, I. D.; Schmidt, P. O.; Burgermeister, T.; Mehlstäubler, T. E.; Peik, E.

    2015-12-01

    In many of the high-precision optical frequency standards with trapped atoms or ions that are under development to date, the ac Stark shift induced by thermal radiation leads to a major contribution to the systematic uncertainty. We present an analysis of the inhomogeneous thermal environment experienced by ions in various types of ion traps. Finite element models which allow the determination of the temperature of the trap structure and the temperature of the radiation were developed for five ion trap designs, including operational traps at PTB and NPL and further optimized designs. Models were refined based on comparison with infrared camera measurement until an agreement of better than 10% of the measured temperature rise at critical test points was reached. The effective temperature rises of the radiation seen by the ion range from 0.8 K to 2.1 K at standard working conditions. The corresponding fractional frequency shift uncertainties resulting from the uncertainty in temperature are in the 10-18 range for optical clocks based on the Sr+ and Yb+ E2 transitions, and even lower for Yb+ E3, In+ and Al+. Issues critical for heating of the trap structure and its predictability were identified and design recommendations developed.

  18. Ion Trapping in the SLAC B-factory High Energy Ring

    SciTech Connect

    Villevald, D.; Heifets, S.; /SLAC

    2006-09-07

    The presence of trapped ions in electron storage rings has caused significant degradation in machine performance. The best known way to prevent the ion trapping is to leave a gap in the electron bunch train. The topic of this paper is the dynamics of ions in the field of the bunch train with uneven bunch filling. We consider High Energy Ring (HER) of the PEP-II B-factory. In the first section we summarize mechanisms of the ion production. Then the transverse and longitudinal dynamics are analyzed for a beam with and without gap. After that, the effect of the ions is considered separating all ions in the ring in several groups depending on their transverse and longitudinal stability. The main effects of the ions are the tune shift and the tune spread of the betatron oscillations of the electrons. The tune spread is produced by bunch to bunch variation of the electric field of ions and by nonlinearity of the field. It is shown that the main contribution to the shift and spread of the betatron tune of the beam is caused by two groups of ions: one-turn ions and trapped ions. One-turn ions are the ions generated during the last passage of the bunch train. Trapped ions are the ions with stable transverse and longitudinal motion. In the last section we discuss shortly related problems of parameters of the clearing electrodes, injection scenario, and collective effects. Clearing electrodes should be located at the defocusing in x-plane quadrupole magnets. An electric DC field of value 1.0 kv/cm will be enough to prevent the ion trapping process. During the injection, it is recommended to fill the bucket with the design number of the particles per bunch N{sub B} before going to the next bucket. In addition, it is recommended to have the sequential filling of the ring, i.e. the filling from one bucket to the next sequentially. It was shown that ions will not be trapped at the location of the interaction point. The reason for this is that the current of the positron beam is

  19. Decomposition of cyclohexane ion induced by intense femtosecond laser fields by ion-trap time-of-flight mass spectrometry

    NASA Astrophysics Data System (ADS)

    Yamazaki, Takao; Watanabe, Yusuke; Kanya, Reika; Yamanouchi, Kaoru

    2016-01-01

    Decomposition of cyclohexane cations induced by intense femtosecond laser fields at the wavelength of 800 nm is investigated by ion-trap time-of-flight mass spectrometry in which cyclohexane cations C6H12+ stored in an ion trap are irradiated with intense femtosecond laser pulses and the generated fragment ions are recorded by time-of-flight mass spectrometry. The various fragment ion species, C5Hn+ (n = 7, 9), C4Hn+ (n = 5-8), C3Hn+ (n = 3-7), C2Hn+ (n = 2-6), and CH3+, identified in the mass spectra show that decomposition of C6H12+ proceeds efficiently by the photo-irradiation. From the laser intensity dependences of the yields of the fragment ion species, the numbers of photons required for producing the respective fragment ions are estimated.

  20. Electrospray/Ion Trap Mass Spectrometry for the Detection and Identification of Organisms

    SciTech Connect

    McLuckey, Scott A.; Stephenson, James L., Jr.

    1997-12-31

    Current electrospray ion trap methodology for rapid mixture analysis of proteins used for the identification of microorganisms is described. Development of ion/ion reaction techniques (e.g. reactions of multiply-charged protein cations with singly-charged anions) from both a fundamental and practical approach are presented, detailing the necessary steps and considerations involved in complex mixture analysis. Data describing the reduction of the initial charge states of electrospray ions to arbitrarily low values, the utility of ion/ion reactions for mixture separation on the millisecond time scale, and effects of excess singly-charged reactants on detection and storage efficiency are illustrated.

  1. Cold ion UV photofragmentation spectroscopy and dynamics (Invited)

    NASA Astrophysics Data System (ADS)

    Feraud, Geraldine; Broquier, Michel; Dedonder, Claude; Jouvet, Christophe; Gregoire, Gilles; Soorkia, Satchin

    2014-12-01

    Up to ten years ago, very little was known about the excited states of protonated amino acids isolated in the gas phase. From the experimental point of view, the study was hampered by the lack of ease of production of such species in sufficient density to apply photon-based techniques. With the development and widespread use of electrospray ionization sources coupled with modified or homebuilt mass spectrometers, there has been significant research into the spectroscopy of biomimetic and biologically relevant molecules. Besides, these species are floppy such that an efficient cooling is required to record clear spectroscopy. Warm protonated species display congested spectra. To extract precise spectroscopic information and avoid spectral congestion, the species need to be cooled down to less than 50 K. We present our latest results on the electronic spectroscopy of protonated phenylalanine and tyrosine on a large spectral domain (225-290 nm). These species are studied in a new simplified apparatus combining an electrospray ionization source, a cryogenically cooled quadrupole ion trap (˜10 K) and time-of-flight mass spectrometry. The role of proton transfer from the NH3+ moiety to the p-ring or to CO of the carboxylic acid group is evidenced by UV photofragment spectroscopy. This first step controls the fragmentation pathways, which strongly depend on the nature of the electronic excited states, i.e. ππ*, ππ*CO and πσNH 3.

  2. Multisectional linear ion trap and novel loading method for optical spectroscopy of electron and nuclear transitions.

    PubMed

    Sysoev, Alexey A; Troyan, Victor I; Borisyuk, Peter V; Krasavin, Andrey V; Vasiliev, Oleg S; Palchikov, Vitaly G; Avdeev, Ivan A; Chernyshev, Denis M; Poteshin, Sergey S

    2015-01-01

    There is a growing need for the development of atomic and nuclear frequency standards because of the important contribution of methods for precision time and frequency measurements to the development of fundamental science, technology, and the economy. It is also conditioned by their potential use in optical clocks and quantum logic applications. It is especially important to develop a universal method that could allow one to use ions of most elements effectively (including ones that are not easily evaporated) proposed for the above-mentioned applications. A linear quadrupole ion trap for the optical spectroscopy of electron and nuclear transitions has been developed and evaluated experimentally. An ion source construction is based on an ultra-high vacuum evaporator in which a metal sample is subjected to an electron beam of energy up to 1 keV, resulting in the appearance of gaseous atoms and ions of various charge state. The linear ion trap consists of five successive quadrupole sections including an entrance quadrupole section, quadrupole mass filter, quadrupole ion guide, ion-trap section, and exit quadrupole section. The same radiofrequency but a different direct current voltage feeds the quadrupole sections. The instrument allows the mass and energy selected trapping of ions from ion beams of various intensities and their localization in the area of laser irradiation. The preliminary results presented show that the proposed instrument and methods allow one to produce effectively up to triply charged thorium ions as well as to trap ions for future spectroscopic study. The instrument is proposed for future use in optical clocks and quantum logic application development. PMID:25906029

  3. Highly charged ion research at the Livermore electron beam ion traps

    SciTech Connect

    Beiersdorfer, P

    2004-01-04

    Spectroscopy performed with the three Livermore electron beam ion traps is reviewed, which is continuing and complementing the innumerable contributions to atomic physics provided over the years by heavy-ion accelerators. Numerous spectrometers were developed that cover the spectral bands from the visible to the hard x ray region. These enabled exhaustive line surveys useful for x-ray astrophysics and for systematic studies along iso-electronic sequences, such as the 4s-4p, 3s-3p, and 2s-2p transitions in ions of the Cu-I, Na-I, and Li-I sequences useful for studying QED and correlation effects as well as for precise determinations of atomic-nuclear interactions. They also enabled measurements of radiative transition probabilities of very long-lived (milli- and microseconds) and very short-live (femtosecond) levels. Because line excitation processes can be controlled by choice of the electron beam energy, the observed line intensities are used to infer cross sections for electron-impact excitation, dielectronic recombination, resonance excitation, and innershell ionization. These capabilities have recently been expanded to simulate x-ray emission from comets by charge exchange. Specific contributions to basic atomic physics, nuclear physics, and high-temperature diagnostics are illustrated.

  4. Quantum information experiments with 2D arrays of hundreds of trapped ions

    NASA Astrophysics Data System (ADS)

    Gilmore, Kevin; Bohnet, Justin; Sawyer, Brian; Britton, Joseph; Wall, Michael; Foss-Feig, Michael; Rey, Ana Maria; Bollinger, John

    2016-05-01

    We summarize recent experimental work with 2D arrays of hundreds of trapped 9 Be+ ions stored in a Penning trap. Penning traps utilize static magnetic and electric fields to confine ions, and enable the trapping and laser cooling of ion crystals larger than typically possible in RF ion traps. We work with single-plane ion crystals where the ions form a triangular lattice through minimization of their Coulomb potential energy. The crystals rotate, and we present numerical studies that determine optimal operating parameters for producing low temperature, stable 2-dimensional crystals with Doppler laser cooling and a rotating wall potential. Our qubit is the electron spin-flip transition in the ground state of 9 Be+ and is sensitive to magnetic field fluctuations. Through mitigation of part-per-billion, vibration-induced magnetic field fluctuations we demonstrate T2 coherence times longer than 50 ms. We engineer long-range Ising interactions with spin-dependent optical dipole forces, and summarize recent measurements that characterize the entanglement generated through single-axis twisting. Supported by: JILA-NSF-PFC-1125844, NSF-PHY-1521080, ARO, AFOSR, AFOSR-MURI.

  5. Magnetic reconnection and modification of the Hall physics due to cold ions at the magnetopause

    NASA Astrophysics Data System (ADS)

    André, M.; Li, W.; Toledo-Redondo, S.; Khotyaintsev, Yu. V.; Vaivads, A.; Graham, D. B.; Norgren, C.; Burch, J.; Lindqvist, P.-A.; Marklund, G.; Ergun, R.; Torbert, R.; Magnes, W.; Russell, C. T.; Giles, B.; Moore, T. E.; Chandler, M. O.; Pollock, C.; Young, D. T.; Avanov, L. A.; Dorelli, J. C.; Gershman, D. J.; Paterson, W. R.; Lavraud, B.; Saito, Y.

    2016-07-01

    Observations by the four Magnetospheric Multiscale spacecraft are used to investigate the Hall physics of a magnetopause magnetic reconnection separatrix layer. Inside this layer of currents and strong normal electric fields, cold (eV) ions of ionospheric origin can remain frozen-in together with the electrons. The cold ions reduce the Hall current. Using a generalized Ohm's law, the electric field is balanced by the sum of the terms corresponding to the Hall current, the v × B drifting cold ions, and the divergence of the electron pressure tensor. A mixture of hot and cold ions is common at the subsolar magnetopause. A mixture of length scales caused by a mixture of ion temperatures has significant effects on the Hall physics of magnetic reconnection.

  6. Observation of single collisionally cooled trapped ions in a buffer gas

    SciTech Connect

    Green, M.; Wodin, J.; De Voe, R.; Fierlinger, P.; Flatt, B.; Gratta, G.; Le Port, F.; Montero Diez, M.; Neilson, R.; O'Sullivan, K.; Pocar, A.; Waldman, S.; Leonard, D. S.; Piepke, A.; Hargrove, C.; Sinclair, D.; Strickland, V.; Fairbank, W. Jr.; Hall, K.; Mong, B.

    2007-08-15

    Individual Ba ions are trapped in a gas-filled linear ion trap and observed with a high signal-to-noise ratio by resonance fluorescence. Single-ion storage times of {approx}5 min ({approx}1 min) are achieved using He (Ar) as a buffer gas at pressures in the range 8x10{sup -5}-4x10{sup -3} torr. Trap dynamics in buffer gases are experimentally studied in the simple case of single ions. In particular, the cooling effects of light gases such as He and Ar and the destabilizing properties of heavier gases such as Xe are studied. A simple model is offered to explain the observed phenomenology.

  7. Effects of trapped electrons on ion reflection in an oblique shock wave

    SciTech Connect

    Toida, Mieko; Inagaki, Junya

    2015-06-15

    A magnetosonic shock wave propagating obliquely to an external magnetic field can trap electrons and accelerate them to ultrarelativistic energies. The trapped electrons excite two-dimensional (2D) electromagnetic fluctuations with finite wavenumbers along the shock front. We study effects of the trapped electrons on ion motions through the 2D fluctuations. It is analytically shown that the fraction of ions reflected from the shock front is enhanced by the 2D fluctuations. This is confirmed by 2D (two space coordinates and three velocities) relativistic, electromagnetic particle simulations with full ion and electron dynamics and calculation of test ions in the electromagnetic fields averaged along the shock front. A comparison between 2D and one-dimensional electromagnetic particle simulations is also shown.

  8. Influence of ion movement in a particle trap on the bound electron g factor

    NASA Astrophysics Data System (ADS)

    Michel, Niklas; Zatorski, Jacek; Keitel, Christoph H.

    2015-11-01

    In the relativistic description of atomic systems in external fields, the total momentum and the external electric field couple to the angular momentum of the individual particles. Therefore, the motional state of an ion in a particle trap influences measurements of internal observables such as energy levels or the g factor. We calculate the resulting relativistic shift of the Larmor frequency and the corresponding g -factor correction for a bound electron in a hydrogenlike ion in the 1 S state due to the ion moving in a Penning trap and show that it is negligible at the current precision of measurements. We also show that the analogous energy shift for measurements with an ion in the ground state of a Paul trap vanishes in leading order.

  9. Theory and simulation of ion Coulomb crystal formation in a Penning trap

    NASA Astrophysics Data System (ADS)

    Asprusten, Martin; Worthington, Simon; Thompson, Richard C.

    2014-01-01

    Ion Coulomb crystals (ICCs) are formed by laser-cooled ions in both radio-frequency and Penning traps. In radio-frequency traps, the crystals are generally stationary. In Penning traps, ICCs always rotate. The frequency of rotation is often set by an applied rotating wall drive that forces the crystal to rotate at the same frequency as the drive. In the absence of any applied rotating or oscillating fields, ICCs in a Penning trap can be in stable equilibrium with a range of rotation frequencies. The density and shape of the crystal adjust with the rotation frequency to ensure that equilibrium is reached. Here, we show that the parameters of the radial laser-cooling beam determine the rotation frequency of a small crystal in a Penning trap when no driving fields are present. We demonstrate, using an approximate theoretical treatment and realistic simulations, that the crystal rotation frequency is independent of the number of ions and the trap parameters, so long as the crystal radius remains smaller than the cooling laser beam waist. As the rotation frequency increases, the crystal eventually becomes a linear string, at which point it is no longer able to adjust its density. Instead, a small amplitude vibration in the zigzag mode of oscillation manifests itself as a rotation of the crystal at a fixed frequency that depends only on the applied trap potential.

  10. An electrodynamic ion funnel interface for greater sensitivity and higher throughput with linear ion trap mass spectrometers

    SciTech Connect

    Page, Jason S.; Tang, Keqi; Smith, Richard D.

    2007-09-01

    An electrospray ionization interface incorporating an electrodynamic ion funnel has been designed and implemented in conjunction with a linear ion trap mass spectrometer (Thermo Electron, LTQ). We found ion transmission to be greatly improved by replacing the standard capillary-skimmer interface with the capillary-ion funnel interface. An infusion study using a serial dilution of a reserpine solution showed that ion injection times to fill the ion trap were reduced by ~90% which resulted in an ~10-fold increase in reported peak intensities. In liquid chromatography (LC)-MS and LC tandem MS (MS/MS) experiments performed using a proteomic sample from the bacterium, Shewanella oneidensis, the ion funnel interface provided an ~7-fold reduction in ion injection (accumulation) times. In a series of LC-MS/MS experiments we found that more dilute S. oneidensis samples provided more peptide and protein identifications when the ion funnel interface was used in place of the standard interface. This improvement was most pronounced at lower sample concentrations, where extended ion accumulation times are required, resulting in an ~2-fold increase in the number of protein identifications. Implementation of the ion funnel interface with a LTQ Fourier transform (FT) MS requiring much greater ion populations resulted in spectrum acquisition times reduced by ~25 to 50%.

  11. Stability of relativistic electron trapping by strong whistler or electromagnetic ion cyclotron waves

    NASA Astrophysics Data System (ADS)

    Artemyev, A. V.; Mourenas, D.; Agapitov, O. V.; Vainchtein, D. L.; Mozer, F. S.; Krasnoselskikh, V.

    2015-08-01

    In the present paper, we investigate the trapping of relativistic electrons by intense whistler-mode waves or electromagnetic ion cyclotron waves in the Earth's radiation belts. We consider the non-resonant impact of additional, lower amplitude magnetic field fluctuations on the stability of electron trapping. We show that such additional non-resonant fluctuations can break the adiabatic invariant corresponding to trapped electron oscillations in the effective wave potential. This destruction results in a diffusive escape of electrons from the trapped regime of motion and thus can lead to a significant reduction of the efficiency of electron acceleration. We demonstrate that when energetic electrons are trapped by intense parallel or very oblique whistler-mode waves, non-resonant magnetic field fluctuations in the whistler-mode frequency range with moderate amplitudes around 3 -15 pT (much less intense than the primary waves) can totally disrupt the trapped motion. However, the trapping of relativistic electrons by electromagnetic ion cyclotron waves is noticeably more stable. We also discuss how the proposed approach can be used to estimate the effects of wave amplitude modulations on the motion of trapped particles.

  12. The measurement of cold ion densities in the plasma trough. [in magnetosphere

    NASA Technical Reports Server (NTRS)

    Harris, K. K.

    1974-01-01

    The cold ion density in the plasma trough region is an important fundamental parameter in the currently proposed mechanisms to describe magnetospheric dynamics. Direct in situ measurements of the cold ion density are generally difficult owing to uncertainties in vehicle potentials and ion temperatures. It is shown that the light ion mass spectrometer from Ogo 5 was very successful in acquiring these data and that vehicle potentials appear not to have been a prohibitive factor. The cold ion plasma trough data show a great deal of variability, indicating a strong dependence on the state of the convection electric field; consequently, average values of cold ion densities in the plasma trough may be significantly different from the actual time-dependent values. The local time plot of plasma trough densities at L = 7 for data acquired over a 1-year period shows the anticipated increase in cold ion density during the daytime and the expected decrease in cold ion density during dusk and early nighttime.

  13. Microfabricated ion trap mass spectrometry for characterization of organics and potential biomarkers

    NASA Astrophysics Data System (ADS)

    Austin, Daniel

    Mass spectrometry is a powerful analytical technique with a strong history in planetary exploration, and is the method of choice for detection and identification of organic and biological molecules. MS instrumentation can also be combined with techniques such as gas chromatography, liquid chromatography, or chiral separation, which are particularly important for analysis of complex mixtures or possible homochirality. Ion traps have several inherent advantages, including speed of analysis (important for GC-MS), MS/MS capabilities (important to identification of unknown compounds), excellent sensitivity, and ease of coupling with ambient ionization techniques that are under development for biomolecule detection. We report on progress in using microfabrication techniques to produce radiofrequency quadrupole ion traps that are much smaller, lighter, and lower power than existing instruments. We produce ion traps using an assembly of two ceramic plates, the facing surfaces of which are lithographically patterned with electrodes. This approach allows great flexibility in the trap geometry, and we have demonstrated working mass spectrometers with quadrupole, linear, and toroidal trapping fields. The approach also allows correction of higher-order terms in the electric field. With this system, mass resolution of up to 1300 has been demonstrated, which is adequate for identification of a wide range of potential biomarkers. Capabilities such as tandem analysis have also been demonstrated. Of particular interest is an ion trap that contains both quadrupole and toroidal trapping regions simultaneously and coaxially. Ions can be trapped as a large reservoir in the toroidal region and introduced in small batches to the quadrupole region for mass analysis. This capability is particularly valuable where the sample of interest is very small, such as microfossil with trace organics, and where the organic inventory is both complex and unknown. Development and results of this device

  14. Production of NaCa+ molecular ions in the ground state from cold atom-ion mixtures by photoassociation via an intermediate state

    NASA Astrophysics Data System (ADS)

    Gacesa, Marko; Montgomery, John A.; Michels, H. Harvey; Côté, Robin

    2016-07-01

    We present a theoretical analysis of optical pathways for formation of cold ground-state (NaCa) + molecular ions via an intermediate state. The formation schemes are based on ab initio potential energy curves and transition dipole moments calculated using effective-core-potential methods of quantum chemistry. In the proposed approach, starting from a mixture of cold trapped Ca+ ions immersed into an ultracold gas of Na atoms, (NaCa) + molecular ions are photoassociated in the excited E +1Σ electronic state and allowed to spontaneously decay either to the ground electronic state or an intermediate state from which the population is transferred to the ground state via an additional optical excitation. By analyzing all possible pathways, we find that the efficiency of a two-photon scheme, via either the B +1Σ or C +1Σ potential, is sufficient to produce significant quantities of ground-state (NaCa) + molecular ions. A single-step process results in lower formation rates that would require either a high-density sample or a very intense photoassociation laser to be viable.

  15. Final Report - Advanced Ion Trap Mass Spectrometry Program - Oak Ridge National Laboratory - Sandia National Laboratory

    SciTech Connect

    Whitten, W.B.

    2002-12-18

    This report covers the three main projects that collectively comprised the Advanced Ion Trap Mass Spectrometry Program. Chapter 1 describes the direct interrogation of individual particles by laser desorption within the ion trap mass spectrometer analyzer. The goals were (1) to develop an ''intelligent trigger'' capable of distinguishing particles of biological origin from those of nonbiological origin in the background and interferent particles and (2) to explore the capability for individual particle identification. Direct interrogation of particles by laser ablation and ion trap mass spectrometry was shown to have good promise for discriminating between particles of biological origin and those of nonbiological origin, although detailed protocols and operating conditions were not worked out. A library of more than 20,000 spectra of various types of biological particles has been assembled. Methods based on multivariate analysis and on neural networks were used to discriminate between particles of biological origin and those of nonbiological origin. It was possible to discriminate between at least some species of bacteria if mass spectra of several hundred similar particles were obtained. Chapter 2 addresses the development of a new ion trap mass analyzer geometry that offers the potential for a significant increase in ion storage capacity for a given set of analyzer operating conditions. This geometry may lead to the development of smaller, lower-power field-portable ion trap mass spectrometers while retaining laboratory-scale analytical performance. A novel ion trap mass spectrometer based on toroidal ion storage geometry has been developed. The analyzer geometry is based on the edge rotation of a quadrupolar ion trap cross section into the shape of a torus. Initial performance of this device was poor, however, due to the significant contribution of nonlinear fields introduced by the rotation of the symmetric ion-trapping geometry. These nonlinear resonances

  16. Self-generated zonal flows in the plasma turbulence driven by trapped-ion and trapped-electron instabilities

    NASA Astrophysics Data System (ADS)

    Drouot, T.; Gravier, E.; Reveille, T.; Collard, M.

    2015-10-01

    This paper presents a study of zonal flows generated by trapped-electron mode and trapped-ion mode micro turbulence as a function of two plasma parameters—banana width and electron temperature. For this purpose, a gyrokinetic code considering only trapped particles is used. First, an analytical equation giving the predicted level of zonal flows is derived from the quasi-neutrality equation of our model, as a function of the density fluctuation levels and the banana widths. Then, the influence of the banana width on the number of zonal flows occurring in the system is studied using the gyrokinetic code. Finally, the impact of the temperature ratio Te/Ti on the reduction of zonal flows is shown and a close link is highlighted between reduction and different gyro-and-bounce-average ion and electron density fluctuation levels. This reduction is found to be due to the amplitudes of gyro-and-bounce-average density perturbations ne and ni gradually becoming closer, which is in agreement with the analytical results given by the quasi-neutrality equation.

  17. Self-generated zonal flows in the plasma turbulence driven by trapped-ion and trapped-electron instabilities

    SciTech Connect

    Drouot, T.; Gravier, E.; Reveille, T.; Collard, M.

    2015-10-15

    This paper presents a study of zonal flows generated by trapped-electron mode and trapped-ion mode micro turbulence as a function of two plasma parameters—banana width and electron temperature. For this purpose, a gyrokinetic code considering only trapped particles is used. First, an analytical equation giving the predicted level of zonal flows is derived from the quasi-neutrality equation of our model, as a function of the density fluctuation levels and the banana widths. Then, the influence of the banana width on the number of zonal flows occurring in the system is studied using the gyrokinetic code. Finally, the impact of the temperature ratio T{sub e}/T{sub i} on the reduction of zonal flows is shown and a close link is highlighted between reduction and different gyro-and-bounce-average ion and electron density fluctuation levels. This reduction is found to be due to the amplitudes of gyro-and-bounce-average density perturbations n{sub e} and n{sub i} gradually becoming closer, which is in agreement with the analytical results given by the quasi-neutrality equation.

  18. Experimental quantum simulations of many-body physics with trapped ions.

    PubMed

    Schneider, Ch; Porras, Diego; Schaetz, Tobias

    2012-02-01

    Direct experimental access to some of the most intriguing quantum phenomena is not granted due to the lack of precise control of the relevant parameters in their naturally intricate environment. Their simulation on conventional computers is impossible, since quantum behaviour arising with superposition states or entanglement is not efficiently translatable into the classical language. However, one could gain deeper insight into complex quantum dynamics by experimentally simulating the quantum behaviour of interest in another quantum system, where the relevant parameters and interactions can be controlled and robust effects detected sufficiently well. Systems of trapped ions provide unique control of both the internal (electronic) and external (motional) degrees of freedom. The mutual Coulomb interaction between the ions allows for large interaction strengths at comparatively large mutual ion distances enabling individual control and readout. Systems of trapped ions therefore exhibit a prominent system in several physical disciplines, for example, quantum information processing or metrology. Here, we will give an overview of different trapping techniques of ions as well as implementations for coherent manipulation of their quantum states and discuss the related theoretical basics. We then report on the experimental and theoretical progress in simulating quantum many-body physics with trapped ions and present current approaches for scaling up to more ions and more-dimensional systems. PMID:22790343

  19. Effect of Trapped Energetic Ions on MHD Activity in Spherical Tori

    SciTech Connect

    R.B. White; Ya.I. Kolesnichenko; V.V. Lutsenko; V.S. Marchenko

    2002-05-30

    It is shown that the increase of beta (the ratio of plasma pressure to the magnetic field pressure) may change the character of the influence of trapped energetic ions on MHD stability in spherical tori. Namely, the energetic ions, which stabilize MHD modes (such as the ideal-kink mode, collisionless tearing mode, and semi-collisional tearing mode) at low beta, have a destabilizing influence at high beta unless the radial distribution of the energetic ions is very peaked.

  20. EBIT (Electron Beam Ion Trap), N-Division Experimental Physics. Annual report, 1994

    SciTech Connect

    Schneider, D.

    1995-10-01

    The experimental groups in the Electron Beam Ion Trap (EBIT) program continue to perform front-line research with trapped and extracted highly charged ions (HCI) in the areas of ion/surface interactions, atomic spectroscopy, electron-ion interaction and structure measurements, highly charged ion confinement, and EBIT development studies. The ion surface/interaction studies which were initiated five years ago have reached a stage where they an carry out routine investigations, as well as produce breakthrough results towards the development of novel nanotechnology. At EBIT and SuperEBIT studies of the x-ray emission from trapped ions continue to produce significant atomic structure data with high precision for few electron systems of high-Z ions. Furthermore, diagnostics development for magnetic and laser fusion, supporting research for the x-ray laser and weapons programs, and laboratory astrophysics experiments in support of NASA`s astrophysics program are a continuing effort. The two-electron contributions to the binding energy of helium like ions were measured for the first time. The results are significant because their precision is an order of magnitude better than those of competing measurements at accelerators, and the novel technique isolates the energy corrections that are the most interesting. The RETRAP project which was initiated three years ago has reached a stage where trapping, confining and electronic cooling of HCI ions up to Th{sup 80+} can be performed routinely. Measurements of the rates and cross sections for electron transfer from H{sub 2} performed to determine the lifetime of HCI up to Xe{sup q+} and Th{sup q+} (35 {le} q {le} 80) have been studied at mean energies estimated to be {approximately} 5 q eV. This combination of heavy ions with very high charges and very low energies is rare in nature, but may be encountered in planned fusion energy demonstration devices, in highly charged ion sources, or in certain astrophysical events.

  1. Bichromatic state-insensitive trapping of cold133Cs-87Rb atomic mixtures

    NASA Astrophysics Data System (ADS)

    Metbulut, M. M.; Renzoni, F.

    2015-12-01

    We investigate simultaneous state-insensitive trapping of a mixture of two different atomic species, Caesium and Rubidium. The magic wavelengths of the Caesium and Rubidium atoms are different, $935.6$ nm and $789.9$ nm respectively, thus single-frequency simultaneous state-insensitive trapping is not possible. We thus identify bichromatic trapping as a viable approach to tune the two magic wavelengths to a common value. Correspondingly, we present several common magic wavelength combinations appropriate for simultaneous state-insensitive trapping of the two atomic species.

  2. Bichromatic state-insensitive trapping of cold 133Cs-87Rb atomic mixtures

    NASA Astrophysics Data System (ADS)

    Metbulut, M. M.; Renzoni, F.

    2015-12-01

    We investigate simultaneous state-insensitive trapping of a mixture of two different atomic species, Caesium and Rubidium. The magic wavelengths of the Caesium and Rubidium atoms are different, 935.6 and 789.9 nm respectively, thus single-frequency simultaneous state-insensitive trapping is not possible. We thus identify bichromatic trapping as a viable approach to tune the two magic wavelengths to a common value. Correspondingly, we present several common magic wavelength combinations appropriate for simultaneous state-insensitive trapping of the two atomic species.

  3. Scalable Microwave Addressing of Trapped Ion Qubits at Fault-tolerant Error Levels

    NASA Astrophysics Data System (ADS)

    Prado Lopes Aude Craik, Diana; Linke, Norbert; Allcock, David; Harty, Thomas; Sepiol, Martin; Stacey, Derek; Steane, Andrew; Lucas, David

    2015-05-01

    We present results obtained with a two-zone, scalable prototype surface-electrode ion trap for storing and individually addressing memory qubits. The trap has 4 integrated microwave electrodes per zone, designed to provide enough degrees of freedom for independent, parallel control of the microwave field amplitude, phase and polarization at each ion. In a demonstration experiment, we use two trap electrodes, one in each zone, to drive Rabi flops in a Calcium-43 ion trapped in the zone we wish to address, while nulling the microwave field in the neighbor zone. We measure Rabi frequency ratios between the addressed and nulled zones of up to 1400, implying that spin-flip errors of order 10-6 are achievable. We also demonstrate polarization control of the microwave field by selectively driving one of two near-degenerate transitions out of the qubit states, one of which is driven by σ+ polarization and the other by σ- polarization. We null the σ+ component of the microwave field at the ion and measure a Rabi frequency ratio of ~ 350 between the σ- and σ+ transitions. Finally, a new design concept for scalable microwave surface-electrode ion traps is presented and progress on the next-generation prototype is reported. This work is supported by the US Army Research Office, EPSRC (UK) and the UK National Quantum Technologies Programme.

  4. Wave packet dynamics of an atomic ion in a Paul trap

    NASA Astrophysics Data System (ADS)

    Hashemloo, A.; Dion, C. M.; Rahali, G.

    2016-07-01

    Using numerical simulations of the time-dependent Schrödinger equation, we study the full quantum dynamics of the motion of an atomic ion in a linear Paul trap. Such a trap is based on a time-varying, periodic electric field and hence corresponds to a time-dependent potential for the ion, which we model exactly. We compare the center-of-mass motion with that obtained from classical equations of motion, as well as to results based on a time-independent effective potential. We also study the oscillations of the width of the ion’s wave packet, including close to the border between stable (bounded) and unstable (unbounded) trajectories. Our results confirm that the center-of-mass motion always follows the classical trajectory, that the width of the wave packet is bounded for trapping within the stability region, and therefore that the classical trapping criterion is fully applicable to quantum motion.

  5. Assembling a ring-shaped crystal in a microfabricated surface ion trap

    SciTech Connect

    Stick, Daniel Lynn; Tabakov, Boyan; Benito, Francisco; Blain, Matthew; Clark, Craig R.; Clark, Susan; Haltli, Raymond A.; Maunz, Peter; Sterk, Jonathan D.; Tigges, Chris

    2015-09-01

    We report on experiments with a microfabricated surface trap designed for confining a chain of ions in a ring. Uniform ion separation over most of the ring is achieved with a rotationally symmetric design and by measuring and suppressing undesired electric fields. After reducing stray fields, the ions are confined primarily by a radio-frequency pseudopotential and their mutual Coulomb repulsion. As a result, approximately 400 40Ca+ ions with an average separation of 9 μm comprise the ion crystal.

  6. Infrared Multiphoton Dissociation of Peptide Cations in a Dual Pressure Linear Ion Trap Mass Spectrometer

    PubMed Central

    Gardner, Myles W.; Smith, Suncerae I.; Ledvina, Aaron R.; Madsen, James A.; Coon, Joshua J.; Schwartz, Jae C.; Stafford, George C.; Brodbelt, Jennifer S.

    2009-01-01

    A dual pressure linear ion trap mass spectrometer was modified to permit infrared multiphoton dissociation (IRMPD) in each of the two cells - the first a high pressure cell operated at nominally 5 × 10-3 Torr and the second a low pressure cell operated at nominally 3 × 10-4 Torr. When IRMPD was performed in the high pressure cell, most peptide ions did not undergo significant photodissociation; however, in the low pressure cell peptide cations were efficiently dissociated with less than 25 ms of IR irradiation regardless of charge state. IRMPD of peptide cations allowed the detection of low m/z product ions including the y1 fragments and immonium ions which are not typically observed by ion trap collision induced dissociation (CID). Photodissociation efficiencies of ~100% and MS/MS (tandem mass spectrometry) efficiencies of greater than 60% were observed for both multiply and singly protonated peptides. In general, higher sequence coverage of peptides was obtained using IRMPD over CID. Further, greater than 90% of the product ion current in the IRMPD mass spectra of doubly charged peptide ions was composed of singly charged product ions compared to the CID mass spectra in which the abundances of the multiply and singly charged product ions were equally divided. Highly charged primary product ions also underwent efficient photodissociation to yield singly charged secondary product ions, thus simplifying the IRMPD product ion mass spectra. PMID:19739654

  7. Comparison of Data Acquisition Strategies on Quadrupole Ion Trap Instrumentation for Shotgun Proteomics

    NASA Astrophysics Data System (ADS)

    Canterbury, Jesse D.; Merrihew, Gennifer E.; MacCoss, Michael J.; Goodlett, David R.; Shaffer, Scott A.

    2014-12-01

    The most common data collection in shotgun proteomics is via data-dependent acquisition (DDA), a process driven by an automated instrument control routine that directs MS/MS acquisition from the highest abundant signals to the lowest. An alternative to DDA is data-independent acquisition (DIA), a process in which a specified range in m/ z is fragmented without regard to prioritization of a precursor ion or its relative abundance in the mass spectrum, thus potentially offering a more comprehensive analysis of peptides than DDA. In this work, we evaluate both DDA and DIA on three different linear ion trap instruments: an LTQ, an LTQ modified with an electrodynamic ion funnel, and an LTQ Velos. These instruments represent both older (LTQ) and newer (LTQ Velos) ion trap designs (i.e., linear versus dual ion traps, respectively), and allow direct comparison of peptide identifications using both DDA and DIA analysis. Further, as the LTQ Velos has an enhanced "S-lens" ion guide to improve ion flux, we found it logical to determine if the former LTQ model could be leveraged by improving sensitivity by modifying with an electrodynamic ion guide of significantly different design to the S-lens. We find that the ion funnel enabled LTQ identifies more proteins in the insoluble fraction of a yeast lysate than the other two instruments in DIA mode, whereas the faster scanning LTQ Velos performs better in DDA mode. We explore reasons for these results, including differences in scan speed, source ion optics, and linear ion trap design.

  8. The use of ion beam cleaning to obtain high quality cold welds with minimal deformation

    NASA Technical Reports Server (NTRS)

    Sater, B. L.; Moore, T. J.

    1978-01-01

    A variation of cold welding is described which utilizes an ion beam to clean mating surfaces prior to joining in a vacuum environment. High quality solid state welds were produced with minimal deformation.

  9. Zinc ion availability--the determinant of efficacy in zinc lozenge treatment of common colds.

    PubMed

    Eby, G A

    1997-10-01

    This is a re-analysis of reports from 1984 to 1992 of double-blind, placebo-controlled, clinical trials of zinc lozenges in the treatment of common colds. This re-analysis was performed to test the hypothesis that major variations in daily zinc ion availability (ZIA) between chemically different lozenge formulations caused differing results in these clinical trials. Solution chemistry computations determined the bioavailability of Zn2+ ions at physiological pH from the lozenges used in these clinical trails. ZIA was derived from Fick's laws of diffusion in a bio-electric field. Lozenges that released Zn2+ ions at physiological pH (positive ZIAs) shortened colds. Lozenges that released negatively charged zinc species at physiological pH (negative ZIAs) lengthened colds. Lozenges having a zero ZIA had no effect on common colds. Lozenges with ZIA = 100 shortened colds by 7 days while ZIA = -55 lozenges lengthened colds by 4.4 days. A linear dose-response relationship exists between ZIAs of zinc lozenges and changes in duration of common colds. It is concluded that: prospective efficacy of zinc lozenges can be predicted based upon readily determined ZIA factors and ZIAs; chemically different zinc lozenge formulations having greatly different ZIAs resulted in greatly differing results in clinical trials; mast cell granule-derived Zn2+ ions are the foundation of the primary immune system; and high ZIA zinc acetate lozenges are beneficial for common colds. PMID:9372416

  10. Planar ion trap (retarding potential analyzer) experiment for atmosphere explorer

    NASA Technical Reports Server (NTRS)

    Hanson, W. B.; Sanatani, S.; Lippincott, C. R.; Zuccaro, D. R.

    1982-01-01

    The retarding potential analyzer and drift meter were carried aboard all three Atmosphere Explorer spacecraft. These instruments measure the total thermal ion concentration and temperature, the bulk thermal ion velocity vector and some limited properties of the relative abundance of H(+), He(+), O(+) and molecular ions. These instruments functioned with no internal failures on all the spacecraft. On AE-E there existed some evidence for external surface contamination that damaged the integrity of the RPA sweep grids. This led to some difficulties in data reduction and interpretation that did not prove to be a disastrous problem. The AE-D spacecraft functioned for only a few months before it re-entered. During this time the satellite suffered from a nutation about the spin axis of about + or - 2 deg. This 2 deg modulation was superimposed upon the ion drift meter horizontal ion arrival angle output requiring the employment of filtering techniques to retrieve the real data.

  11. Initial commissioning results with the NSCL Electron Beam Ion Trap

    SciTech Connect

    Schwarz, S.; Kittimanapun, K.; Lapierre, A.; Leitner, D.; Ottarson, J.; Portillo, M.; Bollen, G.; Lopez-Urrutia, J. R. Crespo; Kester, O.

    2012-02-15

    The ReA reaccelerator is being added to the National Superconducting Cyclotron Laboratory (NSCL) fragmentation facility in order to provide exotic rare-isotope beams, not available at the Isotope Separation On-Line facilities, in the several-MeV/u energy range. The first stage of the NSCL reaccelerator complex, consisting of an EBIT charge breeder, a room-temperature radiofrequency quadrupole (RFQ) accelerator, and superconducting linear accelerator modules, has been completed and is being put into operation. Commissioning of the EBIT has started by extracting charge-bred residual gas ions, ions created from a Ne gas jet directed across the EBIT's electron beam and ions captured from an external test ion source. Charge-bred ions from the Ne gas jet have been extracted as a pulse and accelerated through the RFQ and the two cryomodules.

  12. Stored waveform inverse Fourier transform (SWIFT) ion excitation in trapped-ion mass spectometry: Theory and applications

    NASA Astrophysics Data System (ADS)

    Guan, Shenheng; Marshall, Alan G.

    1996-12-01

    Stored waveform excitation produced by inverse Fourier transformation of a specified magnitude/phase excitation spectrum offers the most general and versatile means for broadband mass-selective excitation and ejection in Penning (FT-ICR) and Paul (quadrupole) ion trap mass spectrometry. Since the last comprehensive review of SWIFT excitation in 1987, the technique has been adopted, modified, and extended widely in both the ICR and quadrupole ion trap communities. Here, we review the principles, variations, algorithms, hardware implementation, and some applications of SWIFT for both ICR and quadrupole ion trap mass spectrometry. We show that the most desirable SWIFT waveform is that optimized to reduce both the time-domain SWIFT maximum amplitude and the amplitude near the start and end of the SWIFT waveform. We examine the "true" magnitude excitation spectrum, obtained by zero-filling and forward Fourier transforming the SWIFT time-domain waveform, in order to evaluate the trade-off between spectral magnitude uniformity and frequency (mass) selectivity. Apodization of the SWIFT waveform is optimally conducted by smoothing the excitation magnitude spectrum prior to generation of the SWIFT waveform by inverse FT. When (as for broadband ejection in a quadrupole ion trap) it is important that ions be excited near-simultaneously over a wide mass range, the phase spectrum (before inverse FT to generate the SWIFT waveform) may be overmodulated or randomly modulated ("filtered noise field"), with the recognition that very substantial non-uniformity in the "true" excitation magnitude spectrum will result.

  13. An electrodynamic ion funnel interface for greater sensitivity and higher throughput with linear ion trap mass spectrometers

    NASA Astrophysics Data System (ADS)

    Page, Jason S.; Tang, Keqi; Smith, Richard D.

    2007-09-01

    An electrospray ionization interface incorporating an electrodynamic ion funnel has been designed and implemented on a linear ion trap mass spectrometer (Thermo Electron, LTQ). We found ion transmission to be greatly improved by replacing the standard capillary-skimmer interface with the capillary-ion funnel interface. An infusion study using a serial dilution of a reserpine solution showed that ion injection (accumulation) times to fill the ion trap at a given automatic gain control (AGC) target value were reduced by ~90% which resulted in an ~10-fold increase in peak intensities. In liquid chromatography tandem MS (LC-MS/MS) experiments performed using a global protein digest sample from the bacterium, Shewanella oneidensis, more peptides and proteins were identified when the ion funnel interface was used in place of the standard interface. This improvement was most pronounced at lower sample concentrations, where extended ion accumulation times are required, resulting in an ~2-fold increase in the number of protein identifications. Implementation of the ion funnel interface on a LTQ Fourier transform (FT) mass spectrometer showed a ~25-50% reduction in spectrum acquisition time. The duty cycle improvement in this case was due to the ion accumulation event contributing a larger portion to the total spectrum acquisition time.

  14. Parity-relevant zitterbewegung and quantum simulation by a single trapped ion

    SciTech Connect

    Wang Kunling; Liu Tao; Feng Mang; Yang Wanli; Wang Kelin

    2010-12-15

    Zitterbewegung (ZB), the trembling of free relativistic electrons in a vacuum, could be simulated by a single trapped ion. We focus on the variations of ZB under different parity conditions and find no ZB in the case of odd or even parity. ZB occurs only for the admixture of the odd- and even-parity states. We also show that a similar role is played by the parity operator for the trapped ion in Fock-state representation and the space-inversion operator for a realistic relativistic electron. Although the ZB effect is invisible in a relativistic electron, preparation of the trapped ion in different parity states is a sophisticated job, which makes it possible to observe the parity-relevant ZB effects with currently available techniques.

  15. A Tuning Method for Electrically Compensated Ion Cyclotron Resonance Mass Spectrometer Traps

    PubMed Central

    Brustkern, Adam M.; Rempel, Don L.; Gross, Michael L.

    2010-01-01

    We describe a method for tuning electrically compensated ion cyclotron resonance (ICR) traps by tracking the observed cyclotron frequency of an ion cloud at different oscillation mode amplitudes. Although we have used this method to tune the compensation voltages of a custom-built electrically compensated trap, the approach is applicable to other designs that incorporate electrical compensation. To evaluate the effectiveness of tuning, we examined the frequency shift as a function of cyclotron orbit size at different z-mode oscillation amplitudes. The cyclotron frequencies varied by ~ 12 ppm for ions with low z-mode oscillation amplitudes compared to those with high z-mode amplitudes. This frequency difference decreased to ~1 ppm by one iteration of trap tuning. PMID:20060743

  16. Electronics of an ion trap with integrated time-of-flight mass spectrometer

    NASA Astrophysics Data System (ADS)

    Schneider, Christian; Schowalter, Steven J.; Yu, Peter; Hudson, Eric R.

    2016-01-01

    Recently, we reported an ion trap experiment with an integrated time-of-flight mass spectrometer (TOFMS) [Phys. Rev. Appl. 2, 034013 (2014)] focussing on the improvement of mass resolution and detection limit due to sample preparation at millikelvin temperatures. The system utilizes a radio-frequency (RF) ion trap with asymmetric drive for storing and manipulating laser-cooled ions and features radial extraction into a compact $275$ mm long TOF drift tube. The mass resolution exceeds $m / \\Delta m = 500$, which provides isotopic resolution over the whole mass range of interest in current experiments and constitutes an improvement of almost an order of magnitude over other implementations. In this manuscript, we discuss the experimental implementation in detail, which is comprised of newly developed drive electronics for generating the required voltages to operate RF trap and TOFMS, as well as control electronics for regulating RF outputs and synchronizing the TOFMS extraction.

  17. Integrated Technologies for Large-Scale Trapped-Ion Quantum Information Processing

    NASA Astrophysics Data System (ADS)

    Sorace-Agaskar, C.; Bramhavar, S.; Kharas, D.; Mehta, K. K.; Loh, W.; Panock, R.; Bruzewicz, C. D.; McConnell, R.; Ram, R. J.; Sage, J. M.; Chiaverini, J.

    2016-05-01

    Atomic ions trapped and controlled using electromagnetic fields hold great promise for practical quantum information processing due to their inherent coherence properties and controllability. However, to realize this promise, the ability to maintain and manipulate large-scale systems is required. We present progress toward the development of, and proof-of-principle demonstrations and characterization of, several technologies that can be integrated with ion-trap arrays on-chip to enable such scaling to practically useful sizes. Of particular use are integrated photonic elements for routing and focusing light throughout a chip without the need for free-space optics. The integration of CMOS electronics and photo-detectors for on-chip control and readout, and methods for monolithic fabrication and wafer-scale integration to incorporate these capabilities into tile-able 2D ion-trap array cells, are also explored.

  18. Rotational dynamics of a diatomic molecular ion in a Paul trap

    SciTech Connect

    Hashemloo, A.; Dion, C. M.

    2015-11-28

    We present models for a heteronuclear diatomic molecular ion in a linear Paul trap in a rigid-rotor approximation, one purely classical and the other where the center-of-mass motion is treated classically, while rotational motion is quantized. We study the rotational dynamics and their influence on the motion of the center-of-mass, in the presence of the coupling between the permanent dipole moment of the ion and the trapping electric field. We show that the presence of the permanent dipole moment affects the trajectory of the ion and that it departs from the Mathieu equation solution found for atomic ions. For the case of quantum rotations, we also evidence the effect of the above-mentioned coupling on the rotational states of the ion.

  19. Rotational dynamics of a diatomic molecular ion in a Paul trap.

    PubMed

    Hashemloo, A; Dion, C M

    2015-11-28

    We present models for a heteronuclear diatomic molecular ion in a linear Paul trap in a rigid-rotor approximation, one purely classical and the other where the center-of-mass motion is treated classically, while rotational motion is quantized. We study the rotational dynamics and their influence on the motion of the center-of-mass, in the presence of the coupling between the permanent dipole moment of the ion and the trapping electric field. We show that the presence of the permanent dipole moment affects the trajectory of the ion and that it departs from the Mathieu equation solution found for atomic ions. For the case of quantum rotations, we also evidence the effect of the above-mentioned coupling on the rotational states of the ion. PMID:26627960

  20. RF Manipulation of Ions in the High Performance Antiproton Trap (HiPAT)

    NASA Technical Reports Server (NTRS)

    Pearson, J. Boise; Martin, James J.; Sims, William H.; Chakrabarti, Suman; Lewis, Raymond A.; Rodgers, Stephen L. (Technical Monitor)

    2002-01-01

    The annihilation of antimatter provides the highest mass specific energy of any other known reaction. Proper harnessing of this energy holds great promise for future space propulsion systems. Many different propulsion concepts have been proposed that take advantage of antimatter, either using matter-antimatter as the primary fuel, or as a 'spark plug' for fusion and fission systems. In order to begin to address these concepts experimentally, a method of storing and transporting antimatter must be developed. The High Performance Antiproton Trap (HiPAT) is a first-generation storage and transportation device designed to store and transport 10(exp 12) antiprotons with a storage half-life of 18 days. It uses a Penning-Malmberg ion trap with a 4T magnetic field and 20 kV potential. This will enable researchers much more flexibility in the design of antimatter experiments related to propulsion. Ions cannot be stored indefinitely in a real trap, as ion cloud instabilities develop from imperfections in manufacturing and misalignments in assembly. Previous work has been done at both the National Institute of Standards and University of California in San Diego in using RF (radio frequency) signals to both diagnose and confine the ion cloud. Two electrodes in the trap have been segmented to allow both reception and transmission of RF waves in the ion cloud. Experiments are underway to determine the number of ions and density in the cloud by "listening" to protons contained in the HiPAT. Currently we believe the density of ions stored in the trap is roughly 10(exp 15) m(exp -3). Development of non-destructive techniques is vital to the project goals, enabling continuous monitoring of the quantities stored in the system. Experimental work is also being done in identifying RF transmission frequencies that can manipulate the density of the cloud, by exchanging energy and momentum between the RF wave and the ions. Preliminary experiments have demonstrated this interaction.