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Sample records for relativistic range quantum

  1. Relativistic Quantum Scars

    SciTech Connect

    Huang, Liang; Lai Yingcheng; Ferry, David K.; Goodnick, Stephen M.; Akis, Richard

    2009-07-31

    The concentrations of wave functions about classical periodic orbits, or quantum scars, are a fundamental phenomenon in physics. An open question is whether scarring can occur in relativistic quantum systems. To address this question, we investigate confinements made of graphene whose classical dynamics are chaotic and find unequivocal evidence of relativistic quantum scars. The scarred states can lead to strong conductance fluctuations in the corresponding open quantum dots via the mechanism of resonant transmission.

  2. Relativistic quantum information

    NASA Astrophysics Data System (ADS)

    Mann, R. B.; Ralph, T. C.

    2012-11-01

    Over the past few years, a new field of high research intensity has emerged that blends together concepts from gravitational physics and quantum computing. Known as relativistic quantum information, or RQI, the field aims to understand the relationship between special and general relativity and quantum information. Since the original discoveries of Hawking radiation and the Unruh effect, it has been known that incorporating the concepts of quantum theory into relativistic settings can produce new and surprising effects. However it is only in recent years that it has become appreciated that the basic concepts involved in quantum information science undergo significant revision in relativistic settings, and that new phenomena arise when quantum entanglement is combined with relativity. A number of examples illustrate that point. Quantum teleportation fidelity is affected between observers in uniform relative acceleration. Entanglement is an observer-dependent property that is degraded from the perspective of accelerated observers moving in flat spacetime. Entanglement can also be extracted from the vacuum of relativistic quantum field theories, and used to distinguish peculiar motion from cosmological expansion. The new quantum information-theoretic framework of quantum channels in terms of completely positive maps and operator algebras now provides powerful tools for studying matters of causality and information flow in quantum field theory in curved spacetimes. This focus issue provides a sample of the state of the art in research in RQI. Some of the articles in this issue review the subject while others provide interesting new results that will stimulate further research. What makes the subject all the more exciting is that it is beginning to enter the stage at which actual experiments can be contemplated, and some of the articles appearing in this issue discuss some of these exciting new developments. The subject of RQI pulls together concepts and ideas from

  3. Relativistic Quantum Cryptography

    NASA Astrophysics Data System (ADS)

    Jeffrey, Evan; Kwiat, Paul

    2006-03-01

    We present results from a relativistic quantum cryptography system which uses photon storage to avoid bit sifting, in principle doubling the useful key rate. Bob stores the photon he receives from Alice in an optical delay line until she sends him the classical basis information, allowing him to measure every photon in the correct basis. Accounting for loss in our 489-ns storage cavity, we achieve a 66% increase in the BB84 key rate. The same system could be used for even greater gains in either the six-state protocol or cryptography using a larger Hilbert space. We show that the security of this protocol is equivalent to standard BB84: assuming the quantum and classical signals are space-like separated, no eavesdropper bound by special relativity can access both simultaneously.

  4. Relativistic quantum cryptography

    SciTech Connect

    Molotkov, S. N.

    2011-03-15

    A new protocol of quantum key distribution is proposed to transmit keys through free space. Along with quantum-mechanical restrictions on the discernibility of nonorthogonal quantum states, the protocol uses additional restrictions imposed by special relativity theory. Unlike all existing quantum key distribution protocols, this protocol ensures key secrecy for a not strictly one-photon source of quantum states and an arbitrary length of a quantum communication channel.

  5. Relativistic quantum private database queries

    NASA Astrophysics Data System (ADS)

    Sun, Si-Jia; Yang, Yu-Guang; Zhang, Ming-Ou

    2015-04-01

    Recently, Jakobi et al. (Phys Rev A 83, 022301, 2011) suggested the first practical private database query protocol (J-protocol) based on the Scarani et al. (Phys Rev Lett 92, 057901, 2004) quantum key distribution protocol. Unfortunately, the J-protocol is just a cheat-sensitive private database query protocol. In this paper, we present an idealized relativistic quantum private database query protocol based on Minkowski causality and the properties of quantum information. Also, we prove that the protocol is secure in terms of the user security and the database security.

  6. Quantum probability assignment limited by relativistic causality

    PubMed Central

    Han, Yeong Deok; Choi, Taeseung

    2016-01-01

    Quantum theory has nonlocal correlations, which bothered Einstein, but found to satisfy relativistic causality. Correlation for a shared quantum state manifests itself, in the standard quantum framework, by joint probability distributions that can be obtained by applying state reduction and probability assignment that is called Born rule. Quantum correlations, which show nonlocality when the shared state has an entanglement, can be changed if we apply different probability assignment rule. As a result, the amount of nonlocality in quantum correlation will be changed. The issue is whether the change of the rule of quantum probability assignment breaks relativistic causality. We have shown that Born rule on quantum measurement is derived by requiring relativistic causality condition. This shows how the relativistic causality limits the upper bound of quantum nonlocality through quantum probability assignment. PMID:26971717

  7. Point form relativistic quantum mechanics and relativistic SU(6)

    NASA Technical Reports Server (NTRS)

    Klink, W. H.

    1993-01-01

    The point form is used as a framework for formulating a relativistic quantum mechanics, with the mass operator carrying the interactions of underlying constituents. A symplectic Lie algebra of mass operators is introduced from which a relativistic harmonic oscillator mass operator is formed. Mass splittings within the degenerate harmonic oscillator levels arise from relativistically invariant spin-spin, spin-orbit, and tensor mass operators. Internal flavor (and color) symmetries are introduced which make it possible to formulate a relativistic SU(6) model of baryons (and mesons). Careful attention is paid to the permutation symmetry properties of the hadronic wave functions, which are written as polynomials in Bargmann spaces.

  8. Quantum Deformations of Einstein's Relativistic Symmetries

    SciTech Connect

    Lukierski, Jerzy

    2006-11-03

    We shall outline two ways of introducing the modification of Einstein's relativistic symmetries of special relativity theory -- the Poincare symmetries. The most complete way of introducing the modifications is via the noncocommutative Hopf-algebraic structure describing quantum symmetries. Two types of quantum relativistic symmetries are described, one with constant commutator of quantum Minkowski space coordinates ({theta}{mu}{nu}-deformation) and second with Lie-algebraic structure of quantum space-time, introducing so-called {kappa}-deformation. The third fundamental constant of Nature - fundamental mass {kappa} or length {lambda} - appears naturally in proposed quantum relativistic symmetry scheme. The deformed Minkowski space is described as the representation space (Hopf-module) of deformed Poincare algebra. Some possible perspectives of quantum-deformed relativistic symmetries will be outlined.

  9. Relativistic quantum information and time machines

    NASA Astrophysics Data System (ADS)

    Ralph, Timothy C.; Downes, Tony G.

    2012-01-01

    Relativistic quantum information combines the informational approach to understanding and using quantum mechanical systems - quantum information - with the relativistic view of the Universe. In this introductory review we examine key results to emerge from this new field of research in physics and discuss future directions. A particularly active area recently has been the question of what happens when quantum systems interact with general relativistic closed timelike curves - effectively time machines. We discuss two different approaches that have been suggested for modelling such situations. It is argued that the approach based on matching the density operator of the quantum state between the future and past most consistently avoids the paradoxes usually associated with time travel.

  10. Relativistic Bohmian interpretation of quantum mechanics

    SciTech Connect

    Nikolic, Hrvoje

    2006-06-27

    I present a relativistic covariant version of the Bohmian interpretation of quantum mechanics and discuss the corresponding measurable predictions. The covariance is incoded in the fact that the nonlocal quantum potential transforms as a scalar, which is a consequence of the fact that the nonlocal wave function transforms as a scalar. The measurable predictions that can be obtained with the deterministic Bohmian interpretation cannot be obtained with the conventional interpretation simply because the conventional probabilistic interpretation does not work in the case of relativistic quantum mechanics.

  11. Towards universal quantum computation through relativistic motion

    PubMed Central

    Bruschi, David Edward; Sabín, Carlos; Kok, Pieter; Johansson, Göran; Delsing, Per; Fuentes, Ivette

    2016-01-01

    We show how to use relativistic motion to generate continuous variable Gaussian cluster states within cavity modes. Our results can be demonstrated experimentally using superconducting circuits where tuneable boundary conditions correspond to mirrors moving with velocities close to the speed of light. In particular, we propose the generation of a quadripartite square cluster state as a first example that can be readily implemented in the laboratory. Since cluster states are universal resources for universal one-way quantum computation, our results pave the way for relativistic quantum computation schemes. PMID:26860584

  12. Towards universal quantum computation through relativistic motion

    NASA Astrophysics Data System (ADS)

    Bruschi, David Edward; Sabín, Carlos; Kok, Pieter; Johansson, Göran; Delsing, Per; Fuentes, Ivette

    2016-02-01

    We show how to use relativistic motion to generate continuous variable Gaussian cluster states within cavity modes. Our results can be demonstrated experimentally using superconducting circuits where tuneable boundary conditions correspond to mirrors moving with velocities close to the speed of light. In particular, we propose the generation of a quadripartite square cluster state as a first example that can be readily implemented in the laboratory. Since cluster states are universal resources for universal one-way quantum computation, our results pave the way for relativistic quantum computation schemes.

  13. Relativistic Quantum Metrology: Exploiting relativity to improve quantum measurement technologies

    PubMed Central

    Ahmadi, Mehdi; Bruschi, David Edward; Sabín, Carlos; Adesso, Gerardo; Fuentes, Ivette

    2014-01-01

    We present a framework for relativistic quantum metrology that is useful for both Earth-based and space-based technologies. Quantum metrology has been so far successfully applied to design precision instruments such as clocks and sensors which outperform classical devices by exploiting quantum properties. There are advanced plans to implement these and other quantum technologies in space, for instance Space-QUEST and Space Optical Clock projects intend to implement quantum communications and quantum clocks at regimes where relativity starts to kick in. However, typical setups do not take into account the effects of relativity on quantum properties. To include and exploit these effects, we introduce techniques for the application of metrology to quantum field theory. Quantum field theory properly incorporates quantum theory and relativity, in particular, at regimes where space-based experiments take place. This framework allows for high precision estimation of parameters that appear in quantum field theory including proper times and accelerations. Indeed, the techniques can be applied to develop a novel generation of relativistic quantum technologies for gravimeters, clocks and sensors. As an example, we present a high precision device which in principle improves the state-of-the-art in quantum accelerometers by exploiting relativistic effects. PMID:24851858

  14. Relativistic quantum metrology: exploiting relativity to improve quantum measurement technologies.

    PubMed

    Ahmadi, Mehdi; Bruschi, David Edward; Sabín, Carlos; Adesso, Gerardo; Fuentes, Ivette

    2014-05-22

    We present a framework for relativistic quantum metrology that is useful for both Earth-based and space-based technologies. Quantum metrology has been so far successfully applied to design precision instruments such as clocks and sensors which outperform classical devices by exploiting quantum properties. There are advanced plans to implement these and other quantum technologies in space, for instance Space-QUEST and Space Optical Clock projects intend to implement quantum communications and quantum clocks at regimes where relativity starts to kick in. However, typical setups do not take into account the effects of relativity on quantum properties. To include and exploit these effects, we introduce techniques for the application of metrology to quantum field theory. Quantum field theory properly incorporates quantum theory and relativity, in particular, at regimes where space-based experiments take place. This framework allows for high precision estimation of parameters that appear in quantum field theory including proper times and accelerations. Indeed, the techniques can be applied to develop a novel generation of relativistic quantum technologies for gravimeters, clocks and sensors. As an example, we present a high precision device which in principle improves the state-of-the-art in quantum accelerometers by exploiting relativistic effects.

  15. Relativistic quantum metrology: exploiting relativity to improve quantum measurement technologies.

    PubMed

    Ahmadi, Mehdi; Bruschi, David Edward; Sabín, Carlos; Adesso, Gerardo; Fuentes, Ivette

    2014-01-01

    We present a framework for relativistic quantum metrology that is useful for both Earth-based and space-based technologies. Quantum metrology has been so far successfully applied to design precision instruments such as clocks and sensors which outperform classical devices by exploiting quantum properties. There are advanced plans to implement these and other quantum technologies in space, for instance Space-QUEST and Space Optical Clock projects intend to implement quantum communications and quantum clocks at regimes where relativity starts to kick in. However, typical setups do not take into account the effects of relativity on quantum properties. To include and exploit these effects, we introduce techniques for the application of metrology to quantum field theory. Quantum field theory properly incorporates quantum theory and relativity, in particular, at regimes where space-based experiments take place. This framework allows for high precision estimation of parameters that appear in quantum field theory including proper times and accelerations. Indeed, the techniques can be applied to develop a novel generation of relativistic quantum technologies for gravimeters, clocks and sensors. As an example, we present a high precision device which in principle improves the state-of-the-art in quantum accelerometers by exploiting relativistic effects. PMID:24851858

  16. A Quantum Relativistic Prisoner's Dilemma Cellular Automaton

    NASA Astrophysics Data System (ADS)

    Alonso-Sanz, Ramón; Carvalho, Márcio; Situ, Haozhen

    2016-06-01

    The effect of variable entangling on the dynamics of a spatial quantum relativistic formulation of the iterated prisoner's dilemma game is studied in this work. The game is played in the cellular automata manner, i.e., with local and synchronous interaction. The game is assessed in fair and unfair contests.

  17. A Quantum Relativistic Prisoner's Dilemma Cellular Automaton

    NASA Astrophysics Data System (ADS)

    Alonso-Sanz, Ramón; Carvalho, Márcio; Situ, Haozhen

    2016-10-01

    The effect of variable entangling on the dynamics of a spatial quantum relativistic formulation of the iterated prisoner's dilemma game is studied in this work. The game is played in the cellular automata manner, i.e., with local and synchronous interaction. The game is assessed in fair and unfair contests.

  18. Optimization of a relativistic quantum mechanical engine.

    PubMed

    Peña, Francisco J; Ferré, Michel; Orellana, P A; Rojas, René G; Vargas, P

    2016-08-01

    We present an optimal analysis for a quantum mechanical engine working between two energy baths within the framework of relativistic quantum mechanics, adopting a first-order correction. This quantum mechanical engine, with the direct energy leakage between the energy baths, consists of two adiabatic and two isoenergetic processes and uses a three-level system of two noninteracting fermions as its working substance. Assuming that the potential wall moves at a finite speed, we derive the expression of power output and, in particular, reproduce the expression for the efficiency at maximum power.

  19. Optimization of a relativistic quantum mechanical engine

    NASA Astrophysics Data System (ADS)

    Peña, Francisco J.; Ferré, Michel; Orellana, P. A.; Rojas, René G.; Vargas, P.

    2016-08-01

    We present an optimal analysis for a quantum mechanical engine working between two energy baths within the framework of relativistic quantum mechanics, adopting a first-order correction. This quantum mechanical engine, with the direct energy leakage between the energy baths, consists of two adiabatic and two isoenergetic processes and uses a three-level system of two noninteracting fermions as its working substance. Assuming that the potential wall moves at a finite speed, we derive the expression of power output and, in particular, reproduce the expression for the efficiency at maximum power.

  20. Optimization of a relativistic quantum mechanical engine.

    PubMed

    Peña, Francisco J; Ferré, Michel; Orellana, P A; Rojas, René G; Vargas, P

    2016-08-01

    We present an optimal analysis for a quantum mechanical engine working between two energy baths within the framework of relativistic quantum mechanics, adopting a first-order correction. This quantum mechanical engine, with the direct energy leakage between the energy baths, consists of two adiabatic and two isoenergetic processes and uses a three-level system of two noninteracting fermions as its working substance. Assuming that the potential wall moves at a finite speed, we derive the expression of power output and, in particular, reproduce the expression for the efficiency at maximum power. PMID:27627248

  1. Relativistic quantum teleportation with superconducting circuits.

    PubMed

    Friis, N; Lee, A R; Truong, K; Sabín, C; Solano, E; Johansson, G; Fuentes, I

    2013-03-15

    We study the effects of relativistic motion on quantum teleportation and propose a realizable experiment where our results can be tested. We compute bounds on the optimal fidelity of teleportation when one of the observers undergoes nonuniform motion for a finite time. The upper bound to the optimal fidelity is degraded due to the observer's motion. However, we discuss how this degradation can be corrected. These effects are observable for experimental parameters that are within reach of cutting-edge superconducting technology.

  2. Quantum mechanics of two relativistic bound fermions

    SciTech Connect

    Giachetti, R.; Sorace, E.

    2006-11-15

    This presentation shows how a joint use of symbolic and numerical programming makes it possible the construction of new quantum mechanical models and the explicit solution for their spectra. Similar methods can be used for investigating quantum systems of different nature with the highest accuracy, as it can be required by the development of new technologies. In particular we deal with the quantization of two relativistic fermions of arbitrary masses interacting by means of a radial potential. The numerical results are given for the Coulomb interaction.

  3. Study of quantum spin correlations of relativistic electron pairs - Testing nonlocality of relativistic quantum mechanics

    NASA Astrophysics Data System (ADS)

    Bodek, K.; Caban, P.; Ciborowski, J.; Enders, J.; Köhler, A.; Kozela, A.; Rembieliński, J.; Rozpedzik, D.; Włodarczyk, M.; Zejma, J.

    2013-11-01

    The Polish-German project QUEST aims at studying relativistic quantum spin correlations of the Einstein-Rosen-Podolsky-Bohm type, through measurement of the correlation function and the corresponding probabilities for relativistic electron pairs. The results will be compared to theoretical predictions obtained by us within the framework of relativistic quantum mechanics, based on assumptions regarding the form of the relativistic spin operator. Agreement or divergence will be interpreted in the context of non-uniqueness of the relativistic spin operator in quantum mechanics as well as dependence of the correlation function on the choice of observables representing the spin. Pairs of correlated electrons will originate from the Mo/ller scattering of polarized 15 MeV electrons provided by the superconducting Darmstadt electron linear accelerator S-DALINAC, TU Darmstadt, incident on a Be target. Spin projections will be determined using the Mott polarimetry technique. Measurements (starting 2013) are planned for longitudinal and transverse beam polarizations and different orientations of the beam polarization vector w.r.t. the Mo/ller scattering plane. This is the first project to study relativistic spin correlations for particles with mass.

  4. Deterministic relativistic quantum bit commitment

    NASA Astrophysics Data System (ADS)

    Adlam, Emily; Kent, Adrian

    2015-06-01

    We describe new unconditionally secure bit commitment schemes whose security is based on Minkowski causality and the monogamy of quantum entanglement. We first describe an ideal scheme that is purely deterministic, in the sense that neither party needs to generate any secret randomness at any stage. We also describe a variant that allows the committer to proceed deterministically, requires only local randomness generation from the receiver, and allows the commitment to be verified in the neighborhood of the unveiling point. We show that these schemes still offer near-perfect security in the presence of losses and errors, which can be made perfect if the committer uses an extra single random secret bit. We discuss scenarios where these advantages are significant.

  5. Teleportation - Travel in the Quantum and Relativistic Realms and Bejond

    NASA Astrophysics Data System (ADS)

    Teodorani, M.

    2007-01-01

    This book, which is devoted to the description and discussion of several methods leading to teleportation, is divided into three main parts: a) foundations of quantum non-locality, quantum particle teleportation and quantum computing; b) foundations of quantum-relativistic teleportation, warp drive propulsion methods and search for extraterrestrial visitation; c) experiments in "psychic teleportation" and problems related to quantum consciousness studies.

  6. Scattering in constraint relativistic quantum dynamics

    NASA Astrophysics Data System (ADS)

    Horwitz, L. P.; Rohrlich, F.

    1982-12-01

    A relativistic scattering theory is developed for a covariant constraint dynamics with direct interparticle interactions. Both time-dependent and time-independent formulations are presented, the latter being a generalization of the Lippmann-Schwinger equation. For the two-body problem, we study the simple case of maximal symmetry which, equivalently, admits both single- and two-time formulations. The two-time formalism illustrates the main features of the general case of N>=3 particles. Perturbation expansions are given for the wave function and for the S matrix. Their structure is similar to those in quantum field theory corresponding to skeleton diagrams.

  7. Relativistic quantum teleportation with superconducting circuits.

    PubMed

    Friis, N; Lee, A R; Truong, K; Sabín, C; Solano, E; Johansson, G; Fuentes, I

    2013-03-15

    We study the effects of relativistic motion on quantum teleportation and propose a realizable experiment where our results can be tested. We compute bounds on the optimal fidelity of teleportation when one of the observers undergoes nonuniform motion for a finite time. The upper bound to the optimal fidelity is degraded due to the observer's motion. However, we discuss how this degradation can be corrected. These effects are observable for experimental parameters that are within reach of cutting-edge superconducting technology. PMID:25166531

  8. Imperfect relativistic mirrors in the quantum regime

    SciTech Connect

    Mendonça, J. T.; Serbeto, A.; Galvão, R. M. O.

    2014-05-15

    The collective backscattering of intense laser radiation by energetic electron beams is considered in the relativistic quantum regime. Exact solutions for the radiation field are obtained, for arbitrary electron pulse shapes and laser intensities. The electron beams act as imperfect nonlinear mirrors on the incident laser radiation. This collective backscattering process can lead to the development of new sources of ultra-short pulse radiation in the gamma-ray domain. Numerical examples show that, for plausible experimental conditions, intense pulses of gamma-rays, due to the double Doppler shift of the harmonics of the incident laser radiation, can be produced using the available technology, with durations less than 1 as.

  9. Causal localizations in relativistic quantum mechanics

    SciTech Connect

    Castrigiano, Domenico P. L. Leiseifer, Andreas D.

    2015-07-15

    Causal localizations describe the position of quantum systems moving not faster than light. They are constructed for the systems with finite spinor dimension. At the center of interest are the massive relativistic systems. For every positive mass, there is the sequence of Dirac tensor-localizations, which provides a complete set of inequivalent irreducible causal localizations. They obey the principle of special relativity and are fully Poincaré covariant. The boosters are determined by the causal position operator and the other Poincaré generators. The localization with minimal spinor dimension is the Dirac localization. Thus, the Dirac equation is derived here as a mere consequence of the principle of causality. Moreover, the higher tensor-localizations, not known so far, follow from Dirac’s localization by a simple construction. The probability of localization for positive energy states results to be described by causal positive operator valued (PO-) localizations, which are the traces of the causal localizations on the subspaces of positive energy. These causal Poincaré covariant PO-localizations for every irreducible massive relativistic system were, all the more, not known before. They are shown to be separated. Hence, the positive energy systems can be localized within every open region by a suitable preparation as accurately as desired. Finally, the attempt is made to provide an interpretation of the PO-localization operators within the frame of conventional quantum mechanics attributing an important role to the negative energy states.

  10. Scattering in the Euclidean formulation of relativistic quantum mechanics

    NASA Astrophysics Data System (ADS)

    Polyzou, Wayne

    2013-10-01

    Euclidean relativistic quantum mechanics is a formulation of relativistic quantum mechanics based on the Osterwalder-Schrader reconstruction theorem that exploits the logical independence of locality from the rest of the axioms of Euclidean field theory. I discuss the properties of Euclidean Green functions necessary for the existence of Møller wave operators and the construction of these wave operators in this formalism. Supported by the US Department of Energy, Grant - DE-AC02-81ER40038.

  11. Ion acoustic shock waves in weakly relativistic multicomponent quantum plasma

    NASA Astrophysics Data System (ADS)

    Gill, T. S.; Bains, A. S.; Bedi, C.

    2010-02-01

    Ion acoustic Shock waves (IASWs) are studied in an collisionless unmagnetized relativistic quantum electron-positron-ion(e-p-i) plasma employing the quantum hydro -dynamic(QHD) model. Korteweg-deVries- Burger equation(KdVB) is derived using small amplitude perturbation expansion method to study the nonlinear propagation of the quantum IASWs. It is found that the coefficients of the KdVB equation are significantely modified by the positron density p, relativistic factor(Ur), temperatures σ, kinematic viscosity η and quantum factor(H).

  12. Relativistic quantum mechanics and relativistic entanglement in the rest-frame instant form of dynamics

    SciTech Connect

    Alba, David; Crater, Horace W.; Lusanna, Luca

    2011-06-15

    A new formulation of relativistic quantum mechanics is proposed in the framework of the rest-frame instant form of dynamics, where the world-lines of the particles are parametrized in terms of the Fokker-Pryce center of inertia and of Wigner-covariant relative 3-coordinates inside the instantaneous Wigner 3-spaces, and where there is a decoupled (non-covariant and non-local) canonical relativistic center of mass. This approach: (a) allows us to make a consistent quantization in every inertial frame; (b) leads to a description of both bound and scattering states; (c) offers new insights on the relativistic localization problem; (d) leads to a non-relativistic limit with a Hamilton-Jacobi treatment of the Newton center of mass; (e) clarifies non-local aspects (spatial non-separability) of relativistic entanglement connected with Lorentz signature and not present in its non-relativistic treatment.

  13. Irreversible degradation of quantum coherence under relativistic motion

    NASA Astrophysics Data System (ADS)

    Wang, Jieci; Tian, Zehua; Jing, Jiliang; Fan, Heng

    2016-06-01

    We study the dynamics of quantum coherence under Unruh thermal noise and seek under which condition the coherence can be frozen in a relativistic setting. We find that the frozen condition is either (i) the initial state is prepared as an incoherence state or (ii) the detectors have no interaction with the external field. That is to say, the decoherence of the detectors' quantum state is irreversible under the influence of thermal noise induced by Unruh radiation. It is shown that quantum coherence approaches zero only in the limit of an infinite acceleration, while quantum entanglement could reduce to zero for a finite acceleration. It is also demonstrated that the robustness of quantum coherence is better than entanglement under the influence of the atom-field interaction for an extremely large acceleration. Therefore, quantum coherence is more robust than entanglement in an accelerating system and the coherence-type quantum resources are more accessible for relativistic quantum information processing tasks.

  14. Electromagnetic wave equations for relativistically degenerate quantum magnetoplasmas.

    PubMed

    Masood, Waqas; Eliasson, Bengt; Shukla, Padma K

    2010-06-01

    A generalized set of nonlinear electromagnetic quantum hydrodynamic (QHD) equations is derived for a magnetized quantum plasma, including collisional, electron spin- 1/2, and relativistically degenerate electron pressure effects that are relevant for dense astrophysical systems, such as white dwarfs. For illustrative purposes, linear dispersion relations are derived for one-dimensional magnetoacoustic waves for a collisionless nonrelativistic degenerate gas in the presence of the electron spin- 1/2 contribution and for magnetoacoustic waves in a plasma containing relativistically degenerate electrons. It is found that both the spin and relativistic degeneracy at high densities tend to slow down the magnetoacoustic wave due to the Pauli paramagnetic effect and relativistic electron mass increase. The present study outlines the theoretical framework for the investigation of linear and nonlinear behaviors of electromagnetic waves in dense astrophysical systems. The results are applied to calculate the magnetoacoustic speeds for both the nonrelativistic and relativistic electron degeneracy cases typical for white dwarf stars. PMID:20866534

  15. Electromagnetic wave equations for relativistically degenerate quantum magnetoplasmas.

    PubMed

    Masood, Waqas; Eliasson, Bengt; Shukla, Padma K

    2010-06-01

    A generalized set of nonlinear electromagnetic quantum hydrodynamic (QHD) equations is derived for a magnetized quantum plasma, including collisional, electron spin- 1/2, and relativistically degenerate electron pressure effects that are relevant for dense astrophysical systems, such as white dwarfs. For illustrative purposes, linear dispersion relations are derived for one-dimensional magnetoacoustic waves for a collisionless nonrelativistic degenerate gas in the presence of the electron spin- 1/2 contribution and for magnetoacoustic waves in a plasma containing relativistically degenerate electrons. It is found that both the spin and relativistic degeneracy at high densities tend to slow down the magnetoacoustic wave due to the Pauli paramagnetic effect and relativistic electron mass increase. The present study outlines the theoretical framework for the investigation of linear and nonlinear behaviors of electromagnetic waves in dense astrophysical systems. The results are applied to calculate the magnetoacoustic speeds for both the nonrelativistic and relativistic electron degeneracy cases typical for white dwarf stars.

  16. Computational relativistic quantum dynamics and its application to relativistic tunneling and Kapitza-Dirac scattering

    NASA Astrophysics Data System (ADS)

    Bauke, Heiko; Klaiber, Michael; Yakaboylu, Enderalp; Hatsagortsyan, Karen Z.; Ahrens, Sven; Müller, Carsten; Keitel, Christoph H.

    2013-05-01

    Computational methods are indispensable to study the quantum dynamics of relativistic light-matter interactions in parameter regimes where analytical methods become inapplicable. We present numerical methods for solving the time-dependent Dirac equation and the time-dependent Klein-Gordon equation and their implementation on high performance graphics cards. These methods allow us to study tunneling from hydrogen-like highly charged ions in strong laser fields and Kapitza-Dirac scattering in the relativistic regime.

  17. Alfven solitary waves in nonrelativistic, relativistic, and ultra-relativistic degenerate quantum plasma

    SciTech Connect

    Rehman, M. A.; Qureshi, M. N. S.; Shah, H. A.; Masood, W.

    2015-10-15

    Nonlinear circularly polarized Alfvén waves are studied in magnetized nonrelativistic, relativistic, and ultrarelativistic degenerate Fermi plasmas. Using the quantum hydrodynamic model, Zakharov equations are derived and the Sagdeev potential approach is used to investigate the properties of the electromagnetic solitary structures. It is seen that the amplitude increases with the increase of electron density in the relativistic and ultrarelativistic cases but decreases in the nonrelativistic case. Both right and left handed waves are considered, and it is seen that supersonic, subsonic, and super- and sub-Alfvénic solitary structures are obtained for different polarizations and under different relativistic regimes.

  18. Relativistic and quantum electrodynamic effects in superheavy elements

    NASA Astrophysics Data System (ADS)

    Schwerdtfeger, Peter; Pašteka, Lukáš F.; Punnett, Andrew; Bowman, Patrick O.

    2015-12-01

    The current status of relativistic electronic structure theory for superheavy elements is reviewed. Recent developments in relativistic quantum theory have made it possible to obtain accurate electronic properties for the trans-actinide elements with the aim to predict their chemical and physical behaviour. The role of quantum electrodynamic effects beyond the no-virtual-pair approximation, which is usually neglected in relativistic molecular calculations, is discussed. Changes in periodic trends due to relativistic effects are outlined for the superheavy elements with nuclear charge Z = 111- 120. We also analyse the role of the negative energy states for the electronic stability of superheavy elements beyond the critical nuclear charge (Zcrit ≈ 170), where the 1s state enters the negative energy continuum at - 2mec2.

  19. Effective photon mass and exact translating quantum relativistic structures

    NASA Astrophysics Data System (ADS)

    Haas, Fernando; Manrique, Marcos Antonio Albarracin

    2016-04-01

    Using a variation of the celebrated Volkov solution, the Klein-Gordon equation for a charged particle is reduced to a set of ordinary differential equations, exactly solvable in specific cases. The new quantum relativistic structures can reveal a localization in the radial direction perpendicular to the wave packet propagation, thanks to a non-vanishing scalar potential. The external electromagnetic field, the particle current density, and the charge density are determined. The stability analysis of the solutions is performed by means of numerical simulations. The results are useful for the description of a charged quantum test particle in the relativistic regime, provided spin effects are not decisive.

  20. A hydrodynamical model for relativistic spin quantum plasmas

    SciTech Connect

    Asenjo, Felipe A.; Munoz, Victor; Valdivia, J. Alejandro; Mahajan, Swadesh M.

    2011-01-15

    Based on the one-body particle-antiparticle Dirac theory of electrons, a set of relativistic quantum fluid equations for a spin half plasma is derived. The particle-antiparticle nature of the relativistic particles is explicit in this fluid theory, which also includes quantum effects such as spin. The nonrelativistic limit is shown to be in agreement with previous attempts to develop a spin plasma theory derived from the Pauli Hamiltonian. Harnessing the formalism to the study of electromagnetic mode propagation, conceptually new phenomena are revealed; the particle-antiparticle effects increase the fluid opacity to these waves, while the spin effects tend to make the fluid more transparent.

  1. Relativistic quantum Darwinism in Dirac fermion and graphene systems

    NASA Astrophysics Data System (ADS)

    Ni, Xuan; Huang, Liang; Lai, Ying-Cheng; Pecora, Louis

    2012-02-01

    We solve the Dirac equation in two spatial dimensions in the setting of resonant tunneling, where the system consists of two symmetric cavities connected by a finite potential barrier. The shape of the cavities can be chosen to yield both regular and chaotic dynamics in the classical limit. We find that certain pointer states about classical periodic orbits can exist, which are signatures of relativistic quantum Darwinism (RQD). These localized states suppress quantum tunneling, and the effect becomes less severe as the underlying classical dynamics in the cavity is chaotic, leading to regularization of quantum tunneling. Qualitatively similar phenomena have been observed in graphene. A physical theory is developed to explain relativistic quantum Darwinism and its effects based on the spectrum of complex eigenenergies of the non-Hermitian Hamiltonian describing the open cavity system.

  2. Nonperturbative approach to relativistic quantum communication channels

    NASA Astrophysics Data System (ADS)

    Landulfo, André G. S.

    2016-05-01

    We investigate the transmission of both classical and quantum information between two arbitrary observers in globally hyperbolic spacetimes using a quantum field as a communication channel. The field is supposed to be in some arbitrary quasifree state and no choice of representation of its canonical commutation relations is made. Both sender and receiver possess some localized two-level quantum system with which they can interact with the quantum field to prepare the input and receive the output of the channel, respectively. The interaction between the two-level systems and the quantum field is such that one can trace out the field degrees of freedom exactly and thus obtain the quantum channel in a nonperturbative way. We end the paper determining the unassisted as well as the entanglement-assisted classical and quantum channel capacities.

  3. Finite- to zero-range relativistic mean-field interactions

    SciTech Connect

    Niksic, T.; Vretenar, D.; Lalazissis, G. A.; Ring, P.

    2008-03-15

    We study the relation between the finite-range (meson-exchange) and zero-range (point-coupling) representations of effective nuclear interactions in the relativistic mean-field framework. Starting from the phenomenological interaction DD-ME2 with density-dependent meson-nucleon couplings, we construct a family of point-coupling effective interactions for different values of the strength parameter of the isoscalar-scalar derivative term. In the meson-exchange picture this corresponds to different values of the {sigma}-meson mass. The parameters of the isoscalar-scalar and isovector-vector channels of the point-coupling interactions are adjusted to nuclear matter and ground-state properties of finite nuclei. By comparing results for infinite and semi-infinite nuclear matter, ground-state masses, charge radii, and collective excitations, we discuss constraints on the parameters of phenomenological point-coupling relativistic effective interaction.

  4. Foundations for proper-time relativistic quantum theory

    NASA Astrophysics Data System (ADS)

    Gill, Tepper L.; Morris, Trey; Kurtz, Stewart K.

    2015-05-01

    This paper is a progress report on the foundations for the canonical proper-time approach to relativistic quantum theory. We first review the the standard square-root equation of relativistic quantum theory, followed by a review of the Dirac equation, providing new insights into the physical properties of both. We then introduce the canonical proper-time theory. For completeness, we give a brief outline of the canonical proper-time approach to electrodynamics and mechanics, and then introduce the canonical proper-time approach to relativistic quantum theory. This theory leads to three new relativistic wave equations. In each case, the canonical generator of proper-time translations is strictly positive definite, so that it represents a particle. We show that the canonical proper-time extension of the Dirac equation for Hydrogen gives results that are consistently closer to the experimental data, when compared to the Dirac equation. However, these results are not sufficient to account for either the Lamb shift or the anomalous magnetic moment.

  5. On the Effect of Quantum Noise in a Quantum-Relativistic Prisoner's Dilemma Cellular Automaton

    NASA Astrophysics Data System (ADS)

    Alonso-Sanz, Ramón; Situ, Haozhen

    2016-09-01

    The disrupting effect of quantum noise on the dynamics of a spatial quantum relativistic formulation of the iterated prisoner's dilemma game with variable entangling is studied in this work. The game is played in the cellular automata manner, i.e., with local and synchronous interaction. The game is assessed in fair and unfair contests.

  6. Absorbing boundary conditions for relativistic quantum mechanics equations

    SciTech Connect

    Antoine, X.; Sater, J.; Fillion-Gourdeau, F.; Bandrauk, A.D.

    2014-11-15

    This paper is devoted to the derivation of absorbing boundary conditions for the Klein–Gordon and Dirac equations modeling quantum and relativistic particles subject to classical electromagnetic fields. Microlocal analysis is the main ingredient in the derivation of these boundary conditions, which are obtained in the form of pseudo-differential equations. Basic numerical schemes are derived and analyzed to illustrate the accuracy of the derived boundary conditions.

  7. Resolution of the Klein Paradox within Relativistic Quantum Mechanics

    SciTech Connect

    Alhaidari, A. D.

    2011-10-27

    We present a resolution of the Klein paradox within the framework of one-particle relativistic quantum mechanics (no pair production). Not only reflection becomes total but the vacuum remains neutral as well. This is accomplished by replacing the pair production process with virtual negative energy ''incidence'' within the barrier in a process analogous to the introduction of image charges in electrostatic and virtual sources in optics.

  8. Spacetime alternatives in the quantum mechanics of a relativistic particle

    SciTech Connect

    Whelan, J.T. Isaac Newton Institute for Mathematical Sciences, 20 Clarkson Road, Cambridge, CB3 0EH )

    1994-11-15

    Hartle's generalized quantum mechanics formalism is used to examine spacetime coarse grainings, i.e., sets of alternatives defined with respect to a region extended in time as well as space, in the quantum mechanics of a free relativistic particle. For a simple coarse graining and suitable initial conditions, tractable formulas are found for branch wave functions. Despite the nonlocality of the positive-definite version of the Klein-Gordon inner product, which means that nonoverlapping branches are not sufficient to imply decoherence, some initial conditions are found to give decoherence and allow the consistent assignment of probabilities.

  9. Multiple-event probability in general-relativistic quantum mechanics

    SciTech Connect

    Hellmann, Frank; Mondragon, Mauricio; Perez, Alejandro; Rovelli, Carlo

    2007-04-15

    We discuss the definition of quantum probability in the context of 'timeless' general-relativistic quantum mechanics. In particular, we study the probability of sequences of events, or multievent probability. In conventional quantum mechanics this can be obtained by means of the 'wave function collapse' algorithm. We first point out certain difficulties of some natural definitions of multievent probability, including the conditional probability widely considered in the literature. We then observe that multievent probability can be reduced to single-event probability, by taking into account the quantum nature of the measuring apparatus. In fact, by exploiting the von-Neumann freedom of moving the quantum/classical boundary, one can always trade a sequence of noncommuting quantum measurements at different times, with an ensemble of simultaneous commuting measurements on the joint system+apparatus system. This observation permits a formulation of quantum theory based only on single-event probability, where the results of the wave function collapse algorithm can nevertheless be recovered. The discussion also bears on the nature of the quantum collapse.

  10. A signed particle formulation of non-relativistic quantum mechanics

    SciTech Connect

    Sellier, Jean Michel

    2015-09-15

    A formulation of non-relativistic quantum mechanics in terms of Newtonian particles is presented in the shape of a set of three postulates. In this new theory, quantum systems are described by ensembles of signed particles which behave as field-less classical objects which carry a negative or positive sign and interact with an external potential by means of creation and annihilation events only. This approach is shown to be a generalization of the signed particle Wigner Monte Carlo method which reconstructs the time-dependent Wigner quasi-distribution function of a system and, therefore, the corresponding Schrödinger time-dependent wave-function. Its classical limit is discussed and a physical interpretation, based on experimental evidences coming from quantum tomography, is suggested. Moreover, in order to show the advantages brought by this novel formulation, a straightforward extension to relativistic effects is discussed. To conclude, quantum tunnelling numerical experiments are performed to show the validity of the suggested approach.

  11. Foundations of a spacetime path formalism for relativistic quantum mechanics

    SciTech Connect

    Seidewitz, Ed

    2006-11-15

    Quantum field theory is the traditional solution to the problems inherent in melding quantum mechanics with special relativity. However, it has also long been known that an alternative first-quantized formulation can be given for relativistic quantum mechanics, based on the parametrized paths of particles in spacetime. Because time is treated similarly to the three space coordinates, rather than as an evolution parameter, such a spacetime approach has proved particularly useful in the study of quantum gravity and cosmology. This paper shows how a spacetime path formalism can be considered to arise naturally from the fundamental principles of the Born probability rule, superposition, and Poincare invariance. The resulting formalism can be seen as a foundation for a number of previous parametrized approaches in the literature, relating, in particular, 'off-shell' theories to traditional on-shell quantum field theory. It reproduces the results of perturbative quantum field theory for free and interacting particles, but provides intriguing possibilities for a natural program for regularization and renormalization. Further, an important consequence of the formalism is that a clear probabilistic interpretation can be maintained throughout, with a natural reduction to nonrelativistic quantum mechanics.

  12. Langmuir waves in semi-relativistic spinless quantum plasmas

    NASA Astrophysics Data System (ADS)

    Ivanov, A. Yu.; Andreev, P. A.; Kuzmenkov, L. S.

    2015-06-01

    Many-particle quantum hydrodynamics based on the Darwin Hamiltonian (the Hamiltonian corresponding to the Darwin Lagrangian) is considered. A force field appearing in the corresponding Euler equation is considered in detail. Contributions from different terms of the Darwin Hamiltonian in the Euler equation are traced. For example, the relativistic correction to the kinetic energy of particles leads to several terms in the Euler equation; these terms have different form. One of them has a form similar to a term appearing from the Darwin term. Hence, the two different mechanisms give analogous contributions in wave dispersion. A microscopic analog of the Biot-Savart law, called the current-current interaction, describing an interaction of moving charges via the magnetic field, is also included in our description. The semi-relativistic generalization of the quantum Bohm potential is obtained. Contribution of the relativistic effects in the spectrum of plasma collective excitations is considered. The contributions of the spin-spin, spin-current, and spin-orbit interactions in this model are considered. The contribution of the spin evolution in the Langmuir wave spectrum is calculated at the propagation of wave perpendicular to the external magnetic field.

  13. Quantum And Relativistic Protocols For Secure Multi-Party Computation

    NASA Astrophysics Data System (ADS)

    Colbeck, Roger

    2009-11-01

    After a general introduction, the thesis is divided into four parts. In the first, we discuss the task of coin tossing, principally in order to highlight the effect different physical theories have on security in a straightforward manner, but, also, to introduce a new protocol for non-relativistic strong coin tossing. This protocol matches the security of the best protocol known to date while using a conceptually different approach to achieve the task. In the second part variable bias coin tossing is introduced. This is a variant of coin tossing in which one party secretly chooses one of two biased coins to toss. It is shown that this can be achieved with unconditional security for a specified range of biases, and with cheat-evident security for any bias. We also discuss two further protocols which are conjectured to be unconditionally secure for any bias. The third section looks at other two-party secure computations for which, prior to our work, protocols and no-go theorems were unknown. We introduce a general model for such computations, and show that, within this model, a wide range of functions are impossible to compute securely. We give explicit cheating attacks for such functions. In the final chapter we discuss the task of expanding a private random string, while dropping the usual assumption that the protocol's user trusts her devices. Instead we assume that all quantum devices are supplied by an arbitrarily malicious adversary. We give two protocols that we conjecture securely perform this task. The first allows a private random string to be expanded by a finite amount, while the second generates an arbitrarily large expansion of such a string.

  14. Volkov solutions for relativistic quantum plasmas.

    PubMed

    Mendonça, J T; Serbeto, A

    2011-02-01

    This work studies the electron quantum states, as determined by the Dirac equation, in the field of electrostatic and electromagnetic waves in a plasma. We discuss the main differences with respect to the vacuum case, and the assumptions under which the vacuum Volkov solutions can be adapted to a plasma. The case of ultrashort electromagnetic wave pulses is also discussed. We also consider the electron states in the field of an electron plasma wave. Modified Volkov solutions of the Dirac equation can also be found. For electron plasma waves such that the phase velocity becomes close to the speed of light, these solutions are exact. Finally, we consider electron states in the field of two waves in a plasma, with relevance to the mixed case where one of the waves is electrostatic and the other is electromagnetic.

  15. Volkov solutions for relativistic quantum plasmas

    SciTech Connect

    Mendonca, J. T.; Serbeto, A.

    2011-02-15

    This work studies the electron quantum states, as determined by the Dirac equation, in the field of electrostatic and electromagnetic waves in a plasma. We discuss the main differences with respect to the vacuum case, and the assumptions under which the vacuum Volkov solutions can be adapted to a plasma. The case of ultrashort electromagnetic wave pulses is also discussed. We also consider the electron states in the field of an electron plasma wave. Modified Volkov solutions of the Dirac equation can also be found. For electron plasma waves such that the phase velocity becomes close to the speed of light, these solutions are exact. Finally, we consider electron states in the field of two waves in a plasma, with relevance to the mixed case where one of the waves is electrostatic and the other is electromagnetic.

  16. Relativistic Quantum Communication and the Structure of Spacetime

    NASA Astrophysics Data System (ADS)

    Martin-Martinez, Eduardo

    We study the transmission of information and correlations through quantum fields in cosmological backgrounds. With this aim, we make use of quantum information tools to quantify the classical and quantum correlations induced by a quantum massless scalar field in two particle detectors, one located in the early universe (Alice's) and the other located at a later time (Bob's). In particular, we focus on two phenomena: a) the consequences on the transmission of information of the violations of the strong Huygens principle for quantum fields, and b) the analysis of the field vacuum correlations via correlation harvesting from Alice to Bob. We will study a standard cosmological model first and then assess whether these results also hold if we use other than the general relativistic dynamics. As a particular example, we will study the transmission of information through the Big Bounce, that replaces the Big Bang, in the effective dynamics of Loop Quantum Cosmology. We show that much more information reaches us through timelike channels (not mediated by real photons) than it is carried by rays of light, which are usually regarded as the only carriers of information.

  17. Relativistic and quantum electrodynamics effects in the helium pair potential.

    PubMed

    Przybytek, M; Cencek, W; Komasa, J; Łach, G; Jeziorski, B; Szalewicz, K

    2010-05-01

    The helium pair potential was computed including relativistic and quantum electrodynamics contributions as well as improved accuracy adiabatic ones. Accurate asymptotic expansions were used for large distances R. Error estimates show that the present potential is more accurate than any published to date. The computed dissociation energy and the average R for the (4)He(2) bound state are 1.62+/-0.03 mK and 47.1+/-0.5 A. These values can be compared with the measured ones: 1.1(-0.2)(+0.3) mK and 52+/-4 A [R. E. Grisenti, Phys. Rev. Lett. 85, 2284 (2000)].

  18. The Quasi-Exactly Solvable Problems in Relativistic Quantum Mechanics

    NASA Astrophysics Data System (ADS)

    Liu, Li-Yan; Hao, Qing-Hai

    2014-06-01

    We study the quasi-exactly solvable problems in relativistic quantum mechanics. We consider the problems for the two-dimensional Klein—Gordon and Dirac equations with equal vector and scalar potentials, and try to find the general form of the quasi-exactly solvable potential. After obtaining the general form of the potential, we present several examples to give the specific forms. In the examples, we show for special parameters the harmonic potential plus Coulomb potential, Killingbeck potential and a quartic potential plus Cornell potential are quasi-exactly solvable potentials.

  19. A finite Zitterbewegung model for relativistic quantum mechanics

    SciTech Connect

    Noyes, H.P.

    1990-02-19

    Starting from steps of length h/mc and time intervals h/mc{sup 2}, which imply a quasi-local Zitterbewegung with velocity steps {plus minus}c, we employ discrimination between bit-strings of finite length to construct a necessary 3+1 dimensional event-space for relativistic quantum mechanics. By using the combinatorial hierarchy to label the strings, we provide a successful start on constructing the coupling constants and mass ratios implied by the scheme. Agreement with experiments is surprisingly accurate. 22 refs., 1 fig.

  20. ``Simplest Molecule'' Clarifies Modern Physics II. Relativistic Quantum Mechanics

    NASA Astrophysics Data System (ADS)

    Harter, William; Reimer, Tyle

    2015-05-01

    A ``simplest molecule'' consisting of CW- laser beam pairs helps to clarify relativity from poster board - I. In spite of a seemingly massless evanescence, an optical pair also clarifies classical and quantum mechanics of relativistic matter and antimatter. Logical extension of (x,ct) and (ω,ck) geometry gives relativistic action functions of Hamiltonian, Lagrangian, and Poincare that may be constructed in a few ruler-and-compass steps to relate relativistic parameters for group or phase velocity, momentum, energy, rapidity, stellar aberration, Doppler shifts, and DeBroglie wavelength. This exposes hyperbolic and circular trigonometry as two sides of one coin connected by Legendre contact transforms. One is Hamiltonian-like with a longitudinal rapidity parameter ρ (log of Doppler shift). The other is Lagrange-like with a transverse angle parameter σ (stellar aberration). Optical geometry gives recoil in absorption, emission, and resonant Raman-Compton acceleration and distinguishes Einstein rest mass, Galilean momentum mass, and Newtonian effective mass. (Molecular photons appear less bullet-like and more rocket-like.) In conclusion, modern space-time physics appears as a simple result of the more self-evident Evenson's axiom: ``All colors go c.''

  1. "simplest Molecule" Clarifies Modern Physics II. Relativistic Quantum Mechanics

    NASA Astrophysics Data System (ADS)

    Reimer, T. C.; Harter, W. G.

    2014-06-01

    A "simplest molecule" consisting of CW-laser beam pairs helps to clarify relativity in Talk I. In spite of a seemingly massless evanescence, an optical pair also clarifies classical and quantum mechanics of relativistic matter and anti-matter. *Logical extension of (x,ct) and (ω,ck) geometry gives relativistic action functions of Hamiltonian, Lagrangian, and Poincare that may be constructed in a few ruler-and-compass steps to relate relativistic parameters for group or phase velocity, momentum, energy, rapidity, stellar aberration, Doppler shifts, and DeBroglie wavelength. This exposes hyperbolic and circular trigonometry as two sides of one coin connected by Legendre contact transforms. One is Hamiltonian-like with a longitudinal rapidity parameter ρ (log of Doppler shift). The other is Lagrange-like with a transverse angle parameter σ (stellar aberration). Optical geometry gives recoil in absorption, emission, and resonant Raman-Compton acceleration and distinguishes Einstein rest mass, Galilean momentum mass, and Newtonian effective mass. (Molecular photons appear less bullet-like and more rocket-like.) In conclusion, modern space-time physics appears as a simple result of the more self-evident Evenson's axiom: "All colors go c."

  2. Atomic electron energies including relativistic effects and quantum electrodynamic corrections

    NASA Technical Reports Server (NTRS)

    Aoyagi, M.; Chen, M. H.; Crasemann, B.; Huang, K. N.; Mark, H.

    1977-01-01

    Atomic electron energies have been calculated relativistically. Hartree-Fock-Slater wave functions served as zeroth-order eigenfunctions to compute the expectation of the total Hamiltonian. A first order correction to the local approximation was thus included. Quantum-electrodynamic corrections were made. For all orbitals in all atoms with 2 less than or equal to Z less than or equal to 106, the following quantities are listed: total energies, electron kinetic energies, electron-nucleus potential energies, electron-electron potential energies consisting of electrostatic and Breit interaction (magnetic and retardation) terms, and vacuum polarization energies. These results will serve for detailed comparison of calculations based on other approaches. The magnitude of quantum electrodynamic corrections is exhibited quantitatively for each state.

  3. Can relativistic bit commitment lead to secure quantum oblivious transfer?

    NASA Astrophysics Data System (ADS)

    He, Guang Ping

    2015-05-01

    While unconditionally secure bit commitment (BC) is considered impossible within the quantum framework, it can be obtained under relativistic or experimental constraints. Here we study whether such BC can lead to secure quantum oblivious transfer (QOT). The answer is not completely negative. In one hand, we provide a detailed cheating strategy, showing that the "honest-but-curious adversaries" in some of the existing no-go proofs on QOT still apply even if secure BC is used, enabling the receiver to increase the average reliability of the decoded value of the transferred bit. On the other hand, it is also found that some other no-go proofs claiming that a dishonest receiver can always decode all transferred bits simultaneously with reliability 100% become invalid in this scenario, because their models of cryptographic protocols are too ideal to cover such a BC-based QOT.

  4. Solution of relativistic quantum optics problems using clusters of graphical processing units

    SciTech Connect

    Gordon, D.F. Hafizi, B.; Helle, M.H.

    2014-06-15

    Numerical solution of relativistic quantum optics problems requires high performance computing due to the rapid oscillations in a relativistic wavefunction. Clusters of graphical processing units are used to accelerate the computation of a time dependent relativistic wavefunction in an arbitrary external potential. The stationary states in a Coulomb potential and uniform magnetic field are determined analytically and numerically, so that they can used as initial conditions in fully time dependent calculations. Relativistic energy levels in extreme magnetic fields are recovered as a means of validation. The relativistic ionization rate is computed for an ion illuminated by a laser field near the usual barrier suppression threshold, and the ionizing wavefunction is displayed.

  5. Quantum diffusion of a relativistic particle in a time-dependent random potential.

    PubMed

    Sepehrinia, Reza

    2015-04-01

    We present a rigorous study of quantum diffusion of a relativistic particle subjected to a time-dependent random potential with δ correlation in time. We find that in the asymptotic time limit the particle wave packet spreads ballistically in contrast with the nonrelativistic case, which in the same situation exhibits superballistic diffusion. The relativistic suppression of wave packet diffusion is discussed in connection with statistical conservation laws that follow from relativistic dynamics. PMID:25974441

  6. Sum-over-histories origin of the composition laws of relativistic quantum mechanics and quantum cosmology

    NASA Astrophysics Data System (ADS)

    Halliwell, Jonathan J.; Ortiz, Miguel E.

    1993-07-01

    This paper is concerned with the question of the existence of composition laws in the sum-over-histories approach to relativistic quantum mechanics and quantum cosmology, and its connection with the existence of a canonical formulation. In nonrelativistic quantum mechanics, the propagator is represented by a sum over histories in which the paths move forward in time. The composition law of the propagator then follows from the fact that the paths intersect an intermediate surface of constant time once and only once, and a partition of the paths according to their crossing position may be affected. In relativistic quantum mechanics, by contrast, the propagators (or Green functions) may be represented by sums over histories in which the paths move backward and forward in time. They therefore intersect surfaces of constant time more than once, and the relativistic composition law, involving a normal derivative term, is not readily recovered. The principal technical aim of this paper is to show that the relativistic composition law may, in fact, be derived directly from a sum over histories by partitioning the paths according to their first crossing position of an intermediate surface. We review the various Green functions of the Klein-Gordon equation, and derive their composition laws. We obtain path-integral representations for all Green functions except the causal one. We use the proper time representation, in which the path integral has the form of a nonrelativistic sum over histories but is integrated over time. The question of deriving the composition laws therefore reduces to the question of factoring the propagators of nonrelativistic quantum mechanics across an arbitrary surface in configuration space. This may be achieved using a known result called the path decomposition expansion (PDX). We give a proof of the PDX using a spacetime lattice definition of the Euclidean propagator. We use the PDX to derive the composition laws of relativistic quantum mechanics

  7. A dynamical time operator in Dirac's relativistic quantum mechanics

    NASA Astrophysics Data System (ADS)

    Bauer, M.

    2014-03-01

    A self-adjoint dynamical time operator is introduced in Dirac's relativistic formulation of quantum mechanics and shown to satisfy a commutation relation with the Hamiltonian analogous to that of the position and momentum operators. The ensuing time-energy uncertainty relation involves the uncertainty in the instant of time when the wave packet passes a particular spatial position and the energy uncertainty associated with the wave packet at the same time, as envisaged originally by Bohr. The instantaneous rate of change of the position expectation value with respect to the simultaneous expectation value of the dynamical time operator is shown to be the phase velocity, in agreement with de Broglie's hypothesis of a particle associated wave whose phase velocity is larger than c. Thus, these two elements of the original basis and interpretation of quantum mechanics are integrated into its formal mathematical structure. Pauli's objection is shown to be resolved or circumvented. Possible relevance to current developments in electron channeling, in interference in time, in Zitterbewegung-like effects in spintronics, graphene and superconducting systems and in cosmology is noted.

  8. Quantum hologram and relativistic hodogram: Magnetic resonance tomography and gravitational wavelet detection

    NASA Astrophysics Data System (ADS)

    Binz, Ernst; Schempp, Walter

    2001-06-01

    Quantum holography is a well established theory of mathematical physics based on harmonic analysis on the Heisenberg Lie group G. The geometric quantization is performed by projectivization of the complexified coadjoint orbit picture of the unitary dual Ĝ of G in order to achieve a geometric adjustment of the quantum scenario to special relativity theory. It admits applications to various imaging modalities such as synthetic aperture radar (SAR) in the microwave range, and, most importantly for the field of non-invasive medical diagnosis, to the clinical imaging modality of magnetic resonance tomography (MRI) in the radio frequency range. Quantum holography explains the quantum teleportation phenomemon through Einstein-Podolsky-Rosen (EPR) channels which is a consequence of the non-locality of phase coherent quantum field theory, the concept of absolute simultaneity of special relativity theory which provides the Einstein equivalence of energy and Fitzgerald-Lorentz dilated mass, and the perfect quantum holographic replication process of molecular genetic information processing. It specifically reveals what was before unobservable in quantum optics, namely the interference phenomena of matter wavelets of Bose-Einstein condensates, and what was before unobservable in special relativity, namely the light in flight (LIF) recording processing by ultrafast laser pulse trains. Finally, it provides a Lie group theoretical approach to the Kruskal coordinatized Schwarzschild manifold of relativistic cosmology with large scale applications to general relativity theory such as gravitational instanton symmetries and the theory of black holes. The direct spinorial detection of gravitational wavelets emitted by the binary radio pulsar PSR 1913+16 and known only by anticipatory system computation so far will also be based on the principles of quantum holography applied to very large array (VLA) radio interferometers. .

  9. Trajectories and causal phase-space approach to relativistic quantum mechanics

    SciTech Connect

    Holland, P.R.; Kyprianidis, A.; Vigier, J.P.

    1987-05-01

    The authors analyze phase-space approaches to relativistic quantum mechanics from the viewpoint of the causal interpretation. In particular, they discuss the canonical phase space associated with stochastic quantization, its relation to Hilbert space, and the Wigner-Moyal formalism. They then consider the nature of Feynman paths, and the problem of nonlocality, and conclude that a perfectly consistent relativistically covariant interpretation of quantum mechanics which retains the notion of particle trajectory is possible.

  10. Quantum Correlations of Two Relativistic Spin-{1}/{2} Particles Under Noisy Channels

    NASA Astrophysics Data System (ADS)

    Mahdian, M.; Mojaveri, B.; Dehghani, A.; Makaremi, T.

    2016-02-01

    We study the quantum correlation dynamics of bipartite spin-{1}/{2} density matrices for two particles under Wigner rotations induced by Lorentz transformations which is transmitted through noisy channels. We compare quantum entanglement, geometric discord(GD), and quantum discord (QD) for bipartite relativistic spin-{1}/{2} states under noisy channels. We find out QD and GD tend to death asymptotically but a sudden change in the decay rate of the entanglement occurs under noisy channels. Also, bipartite relativistic spin density matrices are considered as a quantum channel for teleportation one-qubit state under the influence of depolarizing noise and compare fidelity for various velocities of observers.

  11. Quantum mechanics in noninertial reference frames: Relativistic accelerations and fictitious forces

    NASA Astrophysics Data System (ADS)

    Klink, W. H.; Wickramasekara, S.

    2016-06-01

    One-particle systems in relativistically accelerating reference frames can be associated with a class of unitary representations of the group of arbitrary coordinate transformations, an extension of the Wigner-Bargmann definition of particles as the physical realization of unitary irreducible representations of the Poincaré group. Representations of the group of arbitrary coordinate transformations become necessary to define unitary operators implementing relativistic acceleration transformations in quantum theory because, unlike in the Galilean case, the relativistic acceleration transformations do not themselves form a group. The momentum operators that follow from these representations show how the fictitious forces in noninertial reference frames are generated in quantum theory.

  12. Axioms for quantum mechanics: relativistic causality, retrocausality, and the existence of a classical limit

    NASA Astrophysics Data System (ADS)

    Rohrlich, Daniel

    Y. Aharonov and A. Shimony both conjectured that two axioms - relativistic causality (``no superluminal signalling'') and nonlocality - so nearly contradict each other that only quantum mechanics reconciles them. Can we indeed derive quantum mechanics, at least in part, from these two axioms? No: ``PR-box'' correlations show that quantum correlations are not the most nonlocal correlations consistent with relativistic causality. Here we replace ``nonlocality'' with ``retrocausality'' and supplement the axioms of relativistic causality and retrocausality with a natural and minimal third axiom: the existence of a classical limit, in which macroscopic observables commute. That is, just as quantum mechanics has a classical limit, so must any generalization of quantum mechanics. In this limit, PR-box correlations violaterelativistic causality. Generalized to all stronger-than-quantum bipartite correlations, this result is a derivation of Tsirelson's bound (a theorem of quantum mechanics) from the three axioms of relativistic causality, retrocausality and the existence of a classical limit. Although the derivation does not assume quantum mechanics, it points to the Hilbert space structure that underlies quantum correlations. I thank the John Templeton Foundation (Project ID 43297) and the Israel Science Foundation (Grant No. 1190/13) for support.

  13. Strong Coulomb Coupling in Relativistic Quantum Constraint Dynamics

    NASA Astrophysics Data System (ADS)

    Bawin, M.; Cugnon, J.; Sazdjian, H.

    We study, in the framework of relativistic quantum constraint dynamics, the bound state problem of two oppositely charged spin 1/2 particles, with masses m1 and m2, in mutual electromagnetic interaction. We search for the critical value of the coupling constant α for which the bound state energy reaches the lower continuum, thus indicating the instability of the heavier particle or of the strongly coupled QED vacuum in the equal mass case. Two different choices of the electromagnetic potential are considered, corresponding to different extensions of the substitution rule into the nonperturbative region of α: (i) the Todorov potential, already introduced in the quasipotential approach and used by Crater and Van Alstine in Constraint Dynamics; (ii) a second potential (potential II), characterized by a regular behavior at short distances. For the Todorov potential we find that for m2>m1 there is always a critical value αc of α, depending on m2/m1, for which instability occurs. In the equal mass case, instability is reached at αc=1/2 with a vanishing value of the cutoff radius, generally needed for this potential at short distances. For potential II, on the other hand, we find that instability occurs only for m2>2.16 m1.

  14. On kaonic hydrogen. Quantum field theoretic and relativistic covariant approach

    NASA Astrophysics Data System (ADS)

    Ivanov, A. N.; Cargnelli, M.; Faber, M.; Marton, J.; Troitskaya, N. I.; Zmeskal, J.

    2004-07-01

    We study kaonic hydrogen, the bound K - p state A K p . Within a quantum field theoretic and relativistic covariant approach we derive the energy level displacement of the ground state of kaonic hydrogen in terms of the amplitude of K - p scattering for arbitrary relative momenta. The amplitude of low-energy K - p scattering near threshold is defined by the contributions of three resonances Λ(1405), Λ(1800) and Σ^0(1750) and a smooth elastic background. The amplitudes of inelastic channels of low-energy K - p scattering fit experimental data on the near-threshold behaviour of the cross-sections and the experimental data by the DEAR Collaboration. We use the soft-pion technique (leading order in Chiral Perturbation Theory) for the calculation of the partial width of the radiative decay of pionic hydrogen A_{π p} to n + γ and the Panofsky ratio. The theoretical prediction for the Panofsky ratio agrees well with experimental data. We apply the soft-kaon technique (leading order in Chiral Perturbation Theory) to the calculation of the partial widths of radiative decays of kaonic hydrogen A_{Kp} to Λ^0 + γ and A_{K p} to Σ^0 + γ. We show that the contribution of these decays to the width of the energy level of the ground state of kaonic hydrogen is less than 1%.

  15. Acceleration of positrons by a relativistic electron beam in the presence of quantum effects

    SciTech Connect

    Niknam, A. R.; Aki, H.; Khorashadizadeh, S. M.

    2013-09-15

    Using the quantum magnetohydrodynamic model and obtaining the dispersion relation of the Cherenkov and cyclotron waves, the acceleration of positrons by a relativistic electron beam is investigated. The Cherenkov and cyclotron acceleration mechanisms of positrons are compared together. It is shown that growth rate and, therefore, the acceleration of positrons can be increased in the presence of quantum effects.

  16. Logical inference approach to relativistic quantum mechanics: Derivation of the Klein-Gordon equation

    NASA Astrophysics Data System (ADS)

    Donker, H. C.; Katsnelson, M. I.; De Raedt, H.; Michielsen, K.

    2016-09-01

    The logical inference approach to quantum theory, proposed earlier De Raedt et al. (2014), is considered in a relativistic setting. It is shown that the Klein-Gordon equation for a massive, charged, and spinless particle derives from the combination of the requirements that the space-time data collected by probing the particle is obtained from the most robust experiment and that on average, the classical relativistic equation of motion of a particle holds.

  17. Algebraic approach and coherent states for a relativistic quantum particle in cosmic string spacetime

    NASA Astrophysics Data System (ADS)

    Salazar-Ramírez, M.; Ojeda-Guillén, D.; Mota, R. D.

    2016-09-01

    We study a relativistic quantum particle in cosmic string spacetime in the presence of a magnetic field and a Coulomb-type scalar potential. It is shown that the radial part of this problem possesses the su(1 , 1) symmetry. We obtain the energy spectrum and eigenfunctions of this problem by using two algebraic methods: the Schrödinger factorization and the tilting transformation. Finally, we give the explicit form of the relativistic coherent states for this problem.

  18. Electron Acoustic Solitary Waves in Magnetized Quantum Plasma with Relativistic Degenerated Electrons

    NASA Astrophysics Data System (ADS)

    Zhu, Zhenni; Wu, Zhengwei; Li, Chunhua; Yang, Weihong

    2014-11-01

    A model for the nonlinear properties of obliquely propagating electron acoustic solitary waves in a two-electron populated relativistically quantum magnetized plasma is presented. By using the standard reductive perturbation technique, the Zakharov-Kuznetsov (ZK) equation is derived and this equation gives the solitary wave solution. It is observed that the relativistic effects, the ratio of the cold to hot electron unperturbed number density and the magnetic field normalized by electron cyclotron frequency significantly influence the solitary structures.

  19. Weakly relativistic quantum kinetic theory for electrostatic wave modes in magnetized plasmas

    SciTech Connect

    Hussain, Azhar; Stefan, Martin; Brodin, Gert

    2014-03-15

    We have derived the electrostatic dispersion relation in a magnetized plasma using a recently developed quantum kinetic model based on the Dirac equation. The model contains weakly relativistic spin effects such as Thomas precession, the polarization currents associated with the spin and the spin-orbit coupling. It turns out that for strictly electrostatic perturbations the non-relativistic spin effects vanish, and the modification of the classical dispersion relation is solely associated with the relativistic terms. Several new wave modes appear due the electron spin effects, and an example for astrophysical plasmas are given.

  20. Relativistic hydrodynamical model in the presence of long-range correlations

    SciTech Connect

    Osada, T.

    2010-02-15

    The effects of dynamical long-range correlations over a fluid cell-size scale on a relativistic fluid are discussed. It is shown that such correlations among the fluid elements introduced into the hydrodynamical model induce some weak dissipation and viscosity into the fluid. The influence of the long-range correlations on the entropy current is also discussed.

  1. Quantum resonances in reflection of relativistic electrons and positrons

    NASA Astrophysics Data System (ADS)

    Eykhorn, Yu. L.; Korotchenko, K. B.; Pivovarov, Yu. L.; Takabayashi, Y.

    2015-07-01

    Calculations based on the use of realistic potential of the system of crystallographic planes confirm earlier results on existence of resonances in reflection of relativistic electrons and positrons by the crystal surface, if the crystallographic planes are parallel to the surface.The physical reason of predicted phenomena, similar to the band structure of transverse energy levels, is connected with the Bloch form of the wave functions of electrons (positrons) near the crystallographic planes, which appears both in the case of planar channeling of relativistic electrons (positrons) and in reflection by a crystal surface. Calculations show that positions of maxima in reflection of relativistic electrons and positrons by crystal surface specifically depend on the angle of incidence with respect to the crystal surface and relativistic factor of electrons/positrons. These maxima form the Darwin tables similar to that in ultra-cold neutron diffraction.

  2. Exact treatment of the relativistic double ring-shaped Kratzer potential using the quantum Hamilton-Jacobi formalism

    NASA Astrophysics Data System (ADS)

    Gharbi, A.; Touloum, S.; Bouda, A.

    2015-04-01

    We study the Klein-Gordon equation with noncentral and separable potential under the condition of equal scalar and vector potentials and we obtain the corresponding relativistic quantum Hamilton-Jacobi equation. The application of the quantum Hamilton-Jacobi formalism to the double ring-shaped Kratzer potential leads to its relativistic energy spectrum as well as the corresponding eigenfunctions.

  3. Quantum Monte Carlo studies of relativistic effects in light nuclei

    SciTech Connect

    J. L. Forest; V. R. Pandharipande; A. Arriaga

    1998-05-01

    Relativistic Hamiltonians are defined as the sum of relativistic one-body kinetic energy, two- and three-body potentials and their boost corrections. In this work the authors use the variational Monte Carlo method to study two kinds of relativistic effects in the binding energy of {sup 3}H and {sup 4}He. The first is due to the nonlocalities in the relativistic kinetic energy and relativistic one-pion exchange potential (OPEP), and the second is from boost interaction. The OPEP contribution is reduced by about 15% by the relativistic nonlocality, which may also have significant effects on pion exchange currents. However, almost all of this reduction is canceled by changes in the kinetic energy and other interaction terms, and the total effect of the nonlocalities on the binding energy is very small. The boost interactions, on the other hand, give repulsive contributions of 0.4 (1.9) MeV in {sup 3}H ({sup 4}He) and account for 37% of the phenomenological part of the three-nucleon interaction needed in the nonrelativistic Hamiltonians.

  4. Relativistic quantum effects of confining potentials on the Klein-Gordon oscillator

    NASA Astrophysics Data System (ADS)

    Vitória, R. L. L.; Bakke, K.

    2016-02-01

    The behaviour of the Klein-Gordon oscillator under the influence of linear and Coulomb-type potentials is investigated. The introduction of the scalar potentials is made by modifying the mass term of the Klein-Gordon equation, then, by searching for relativistic bound states, a particular quantum effect can be observed: a dependence of the angular frequency of the Klein-Gordon oscillator on the quantum numbers associated with the radial modes and the angular momentum. As an example, we analyse the angular frequency and the energy level associated with the ground state of the relativistic system.

  5. Universal Quantum Computing:. Third Gen Prototyping Utilizing Relativistic `Trivector' R-Qubit Modeling Surmounting Uncertainty

    NASA Astrophysics Data System (ADS)

    Amoroso, Richard L.; Kauffman, Louis H.; Giandinoto, Salvatore

    2013-09-01

    We postulate bulk universal quantum computing (QC) cannot be achieved without surmounting the quantum uncertainty principle, an inherent barrier by empirical definition in the regime described by the Copenhagen interpretation of quantum theory - the last remaining hurdle to bulk QC. To surmount uncertainty with probability 1, we redefine the basis for the qubit utilizing a unique form of M-Theoretic Calabi-Yau mirror symmetry cast in an LSXD Dirac covariant polarized vacuum with an inherent `Feynman synchronization backbone'. This also incorporates a relativistic qubit (r-qubit) providing additional degrees of freedom beyond the traditional Block 2-sphere qubit bringing the r-qubit into correspondence with our version of Relativistic Topological Quantum Field Theory (RTQFT). We present a 3rd generation prototype design for simplifying bulk QC implementation.

  6. Relativistic x-ray free-electron lasers in the quantum regime.

    PubMed

    Eliasson, Bengt; Shukla, P K

    2012-06-01

    We present a nonlinear theory for relativistic x-ray free-electron lasers in the quantum regime, using a collective Klein-Gordon (KG) equation (for relativistic electrons), which is coupled with the Maxwell-Poisson equations for the electromagnetic and electrostatic fields. In our model, an intense electromagnetic wave is used as a wiggler which interacts with a relativistic electron beam to produce coherent tunable radiation. The KG-Maxwell-Poisson model is used to derive a general nonlinear dispersion relation for parametric instabilities in three space dimensions, including an arbitrarily large amplitude electromagnetic wiggler field. The nonlinear dispersion relation reveals the importance of quantum recoil effects and oblique scattering of the radiation that can be tuned by varying the beam energy. PMID:23005155

  7. Relativistic x-ray free-electron lasers in the quantum regime.

    PubMed

    Eliasson, Bengt; Shukla, P K

    2012-06-01

    We present a nonlinear theory for relativistic x-ray free-electron lasers in the quantum regime, using a collective Klein-Gordon (KG) equation (for relativistic electrons), which is coupled with the Maxwell-Poisson equations for the electromagnetic and electrostatic fields. In our model, an intense electromagnetic wave is used as a wiggler which interacts with a relativistic electron beam to produce coherent tunable radiation. The KG-Maxwell-Poisson model is used to derive a general nonlinear dispersion relation for parametric instabilities in three space dimensions, including an arbitrarily large amplitude electromagnetic wiggler field. The nonlinear dispersion relation reveals the importance of quantum recoil effects and oblique scattering of the radiation that can be tuned by varying the beam energy.

  8. Exploring the propagation of relativistic quantum wavepackets in the trajectory-based formulation

    NASA Astrophysics Data System (ADS)

    Tsai, Hung-Ming; Poirier, Bill

    2016-03-01

    In the context of nonrelativistic quantum mechanics, Gaussian wavepacket solutions of the time-dependent Schrödinger equation provide useful physical insight. This is not the case for relativistic quantum mechanics, however, for which both the Klein-Gordon and Dirac wave equations result in strange and counterintuitive wavepacket behaviors, even for free-particle Gaussians. These behaviors include zitterbewegung and other interference effects. As a potential remedy, this paper explores a new trajectory-based formulation of quantum mechanics, in which the wavefunction plays no role [Phys. Rev. X, 4, 040002 (2014)]. Quantum states are represented as ensembles of trajectories, whose mutual interaction is the source of all quantum effects observed in nature—suggesting a “many interacting worlds” interpretation. It is shown that the relativistic generalization of the trajectory-based formulation results in well-behaved free-particle Gaussian wavepacket solutions. In particular, probability density is positive and well-localized everywhere, and its spatial integral is conserved over time—in any inertial frame. Finally, the ensemble-averaged wavepacket motion is along a straight line path through spacetime. In this manner, the pathologies of the wave-based relativistic quantum theory, as applied to wavepacket propagation, are avoided.

  9. On the Methods for Constructing Meson-Baryon Reaction Models within Relativistic Quantum Field Theory

    SciTech Connect

    B. Julia-Diaz, H. Kamano, T.-S. H. Lee, A. Matsuyama, T. Sato, N. Suzuki

    2009-04-01

    Within the relativistic quantum field theory, we analyze the differences between the $\\pi N$ reaction models constructed from using (1) three-dimensional reductions of Bethe-Salpeter Equation, (2) method of unitary transformation, and (3) time-ordered perturbation theory. Their relations with the approach based on the dispersion relations of S-matrix theory are dicusssed.

  10. Construction of relativistic quantum theory: a progress report

    SciTech Connect

    Noyes, H.P.

    1986-06-01

    We construct the particulate states of quantum physics using a recursive computer program that incorporates non-determinism by means of locally arbitrary choices. Quantum numbers and coupling constants arise from the construction via the unique 4-level combinatorial hierarchy. The construction defines indivisible quantum events with the requisite supraluminal correlations, yet does not allow supraluminal communication. Measurement criteria incorporate c, h-bar and m/sub p/ or (not ''and'') G, connected to laboratory events via finite particle number scattering theory and the counter paradigm. The resulting theory is discrete throughout, contains no infinities, and, as far as we have developed it, is in agreement with quantum mechanical and cosmological fact.

  11. Relativistic Two and Three-Particle Bound States in Scalar Quantum Field Theory.

    NASA Astrophysics Data System (ADS)

    di Leo, Leo

    This thesis is concerned with the application of the variational method, within the Hamiltonian formalism of quantum field theory (QFT), to describe relativistic two and three particle states in scalar field theories. Two models are considered: scalar particles interacting through the exchange of scalar quanta, and the Higgs sector of the Minimal Standard Model. We derive relativistic particle-antiparticle wave equations for scalar particles, phi and |phi, interacting via a massive or massless scalar field, chi (the Wick-Cutkosky model), using simple Fock space ansatze. The variational method, within the Hamiltonian formalism of QFT, is used to derive equations with and without coupling of this quasi-bound phi|phi system to the chichi decay channel. The equations are then approximately decoupled to yield a relativistic momentum-space (Schrodinger-like) wave equation from which we determine bound-state energies numerically, perturbatively or variationally for various strengths of the coupling. Bound-state energies in the massless case are compared to the known ladder Bethe-Salpeter and light-cone solutions of this model. In the case of coupling to the decay channel, which is easily accomplished in the present formalism by expanding our Fock-space ansatz, the quasi-bound phi|phi states are seen to arise as resonances in the chichi scattering cross section. Numerical results are presented for the massive and massless chi case for various coupling strengths. The same variational method can be easily extended to derive relativistic three-particle wave equations for scalar particles phi,phi and |phi, interacting via a massive or massless scalar field, chi. In this case, the equations are obtained using a simple |phiphi|phi > +| phiphi|{phi}chi > ansatz. Approximate variational solutions (using product-type hydrogenic wave functions) of these equations are presented for various strengths of the coupling. The magnitude of the relativistic effects in the three

  12. Weakly nonlinear ion-acoustic excitations in a relativistic model for dense quantum plasma.

    PubMed

    Behery, E E; Haas, F; Kourakis, I

    2016-02-01

    The dynamics of linear and nonlinear ionic-scale electrostatic excitations propagating in a magnetized relativistic quantum plasma is studied. A quantum-hydrodynamic model is adopted and degenerate statistics for the electrons is taken into account. The dispersion properties of linear ion acoustic waves are examined in detail. A modified characteristic charge screening length and "sound speed" are introduced, for relativistic quantum plasmas. By employing the reductive perturbation technique, a Zakharov-Kuznetzov-type equation is derived. Using the small-k expansion method, the stability profile of weakly nonlinear slightly supersonic electrostatic pulses is also discussed. The effect of electron degeneracy on the basic characteristics of electrostatic excitations is investigated. The entire analysis is valid in a three-dimensional as well as in two-dimensional geometry. A brief discussion of possible applications in laboratory and space plasmas is included. PMID:26986431

  13. Geometric approach to non-relativistic quantum dynamics of mixed states

    NASA Astrophysics Data System (ADS)

    Gimeno, Vicent; Sotoca, Jose M.

    2013-05-01

    In this paper we propose a geometrization of the non-relativistic quantum mechanics for mixed states. Our geometric approach makes use of the Uhlmann's principal fibre bundle to describe the space of mixed states and as a novelty tool, to define a dynamic-dependent metric tensor on the principal manifold, such that the projection of the geodesic flow to the base manifold gives the temporal evolution predicted by the von Neumann equation. Using that approach we can describe every conserved quantum observable as a Killing vector field, and provide a geometric proof for the Poincaré quantum recurrence in a physical system with finite energy levels.

  14. Dirac Equation and Quantum Relativistic Effects in a Single Trapped Ion

    SciTech Connect

    Lamata, L.; Leon, J.; Schaetz, T.; Solano, E.

    2007-06-22

    We present a method of simulating the Dirac equation in 3+1 dimensions for a free spin-1/2 particle in a single trapped ion. The Dirac bispinor is represented by four ionic internal states, and position and momentum of the Dirac particle are associated with the respective ionic variables. We show also how to simulate the simplified 1+1 case, requiring the manipulation of only two internal levels and one motional degree of freedom. Moreover, we study relevant quantum-relativistic effects, like the Zitterbewegung and Klein's paradox, the transition from massless to massive fermions, and the relativistic and nonrelativistic limits, via the tuning of controllable experimental parameters.

  15. General relativistic effects in quantum interference of “clocks”

    NASA Astrophysics Data System (ADS)

    Zych, M.; Pikovski, I.; Costa, F.; Brukner, Č.

    2016-06-01

    Quantum mechanics and general relativity have been each successfully tested in numerous experiments. However, the regime where both theories are jointly required to explain physical phenomena remains untested by laboratory experiments, and is also not fully understood by theory. This contribution reviews recent ideas for a new type of experiments: quantum interference of “clocks”, which aim to test novel quantum effects that arise from time dilation. “Clock” interference experiments could be realised with atoms or photons in near future laboratory experiments.

  16. Quantum dynamics of relativistic bosons through nonminimal vector square potentials

    NASA Astrophysics Data System (ADS)

    de Oliveira, Luiz P.

    2016-09-01

    The dynamics of relativistic bosons (scalar and vectorial) through nonminimal vector square (well and barrier) potentials is studied in the Duffin-Kemmer-Petiau (DKP) formalism. We show that the problem can be mapped in effective Schrödinger equations for a component of the DKP spinor. An oscillatory transmission coefficient is found and there is total reflection. Additionally, the energy spectrum of bound states is obtained and reveals the Schiff-Snyder-Weinberg effect, for specific conditions the potential lodges bound states of particles and antiparticles.

  17. Quantum interferometric visibility as a witness of general relativistic proper time

    PubMed Central

    Zych, Magdalena; Costa, Fabio; Pikovski, Igor; Brukner, Časlav

    2011-01-01

    Current attempts to probe general relativistic effects in quantum mechanics focus on precision measurements of phase shifts in matter–wave interferometry. Yet, phase shifts can always be explained as arising because of an Aharonov–Bohm effect, where a particle in a flat space–time is subject to an effective potential. Here we propose a quantum effect that cannot be explained without the general relativistic notion of proper time. We consider interference of a 'clock'—a particle with evolving internal degrees of freedom—that will not only display a phase shift, but also reduce the visibility of the interference pattern. According to general relativity, proper time flows at different rates in different regions of space–time. Therefore, because of quantum complementarity, the visibility will drop to the extent to which the path information becomes available from reading out the proper time from the 'clock'. Such a gravitationally induced decoherence would provide the first test of the genuine general relativistic notion of proper time in quantum mechanics. PMID:22009037

  18. Local thermodynamical equilibrium and the frame for a quantum relativistic fluid

    NASA Astrophysics Data System (ADS)

    Becattini, Francesco; Bucciantini, Leda; Grossi, Eduardo; Tinti, Leonardo

    2015-05-01

    We discuss the concept of local thermodynamical equilibrium in relativistic hydrodynamics in flat spacetime in a quantum statistical framework without an underlying kinetic description, suitable for strongly interacting fluids. We show that the appropriate definition of local equilibrium naturally leads to the introduction of a relativistic hydrodynamical frame in which the four-velocity vector is the one of a relativistic thermometer at equilibrium with the fluid, parallel to the inverse temperature four-vector , which then becomes a primary quantity. We show that this frame is the most appropriate for the expansion of the stress-energy tensor from local thermodynamical equilibrium and that therein the local laws of thermodynamics take on their simplest form. We discuss the difference between the frame and Landau frame and present an instance where they differ.

  19. Coherent radiation of relativistic electrons in dielectric fibers in the millimeter wavelength range

    NASA Astrophysics Data System (ADS)

    Naumenko, G. A.; Potylitsyn, A. P.; Bleko, V. V.; Soboleva, V. V.

    2015-02-01

    The generation of visible light by a relativistic electron beam in dielectric fibers was considered in X. Artru and C. Ray, Nucl. Inst. Meth. B 309, 4 (2013), where the characteristics of radiation induced in a fiber by the electromagnetic field of a relativistic charged particle were studied and it was emphasized that they differ from those in the traditional mechanisms of radiation such as transition and diffraction. We have experimentally studied the characteristics of such a radiation in the millimeter wavelength range. It has been shown that radiation can be generated through different mechanisms depending on the geometry of the position of a fiber with respect to the trajectory of the charged particle. Fibers have been shown to be promising for nondestructive diagnostics of accelerator beams.

  20. Relativistic quantum channel of communication through field quanta

    SciTech Connect

    Cliche, M.; Kempf, A.

    2010-01-15

    Setups in which a system Alice emits field quanta that a system Bob receives are prototypical for wireless communication and have been extensively studied. In the most basic setup, Alice and Bob are modeled as Unruh-DeWitt detectors for scalar quanta, and the only noise in their communication is due to quantum fluctuations. For this basic setup, we construct the corresponding information-theoretic quantum channel. We calculate the classical channel capacity as a function of the spacetime separation, and we confirm that the classical as well as the quantum channel capacity are strictly zero for spacelike separations. We show that this channel can be used to entangle Alice and Bob instantaneously. Alice and Bob are shown to extract this entanglement from the vacuum through a Casimir-Polder effect.

  1. Optical-lattice Hamiltonians for relativistic quantum electrodynamics

    SciTech Connect

    Kapit, Eliot; Mueller, Erich

    2011-03-15

    We show how interpenetrating optical lattices containing Bose-Fermi mixtures can be constructed to emulate the thermodynamics of quantum electrodynamics (QED). We present models of neutral atoms on lattices in 1+1, 2+1, and 3+1 dimensions whose low-energy effective action reduces to that of photons coupled to Dirac fermions of the corresponding dimensionality. We give special attention to (2+1)-dimensional quantum electrodynamics (QED3) and discuss how two of its most interesting features, chiral symmetry breaking and Chern-Simons physics, could be observed experimentally.

  2. Ultrashort-Pulse Child-Langmuir Law in the Quantum and Relativistic Regimes

    SciTech Connect

    Ang, L. K.; Zhang, P.

    2007-04-20

    This Letter presents a consistent quantum and relativistic model of short-pulse Child-Langmuir (CL) law, of which the pulse length {tau} is less than the electron transit time in a gap of spacing D and voltage V. The classical value of the short-pulse CL law is enhanced by a large factor due to quantum effects when the pulse length and the size of the beam are, respectively, in femtosecond duration and nanometer scale. At high voltage larger than the electron rest mass, relativistic effects will suppress the enhancement of short-pulse CL law, which is confirmed by particle-in-cell simulation. When the pulse length is much shorter than the gap transit time, the current density is proportional to V, and to the inverse power of D and {tau}.

  3. Link between the relativistic canonical quantum mechanics of arbitrary spin and the corresponding field theory

    NASA Astrophysics Data System (ADS)

    Simulik, Volodimir

    2016-01-01

    The new relativistic equations of motion for the particles with arbitrary spin and nonzero mass have been introduced. The axiomatic level description of the relativistic canonical quantum mechanics of the arbitrary mass and spin has been given. The 64-dimensional ClR(0,6) algebra in terms of Dirac gamma matrices has been suggested. The link between the relativistic canonical quantum mechanics of the arbitrary spin and the covariant local field theory has been found. Different methods of the Dirac equation derivation have been reviewed. The manifestly covariant field equations for an arbitrary spin that follow from the quantum mechanical equations have been considered. The covariant local field theory equations for spin s = (1,1) particle-antiparticle doublet, spin s = (1,0,1,0) particle antiparticle multiplet, spin s = (3/2,3/2) particle-antiparticle doublet, spin s = (2,2) particle-antiparticle doublet, spin s = (2,0,2,0) particle-antiparticle multiplet and spin s = (2,1,2,1) particle-antiparticle multiplet have been introduced. The Maxwell-like equations for the boson with spin s = 1 and nonzero mass have been introduced as well.

  4. Some Mathematical Structures Including Simplified Non-Relativistic Quantum Teleportation Equations and Special Relativity

    SciTech Connect

    Woesler, Richard

    2007-02-21

    The computations of the present text with non-relativistic quantum teleportation equations and special relativity are totally speculative, physically correct computations can be done using quantum field theory, which remain to be done in future. Proposals for what might be called statistical time loop experiments with, e.g., photon polarization states are described when assuming the simplified non-relativistic quantum teleportation equations and special relativity. However, a closed time loop would usually not occur due to phase incompatibilities of the quantum states. Histories with such phase incompatibilities are called inconsistent ones in the present text, and it is assumed that only consistent histories would occur. This is called an exclusion principle for inconsistent histories, and it would yield that probabilities for certain measurement results change. Extended multiple parallel experiments are proposed to use this statistically for transmission of classical information over distances, and regarding time. Experiments might be testable in near future. However, first a deeper analysis, including quantum field theory, remains to be done in future.

  5. Variable mass theories in relativistic quantum mechanics as an explanation for anomalous low energy nuclear phenomena

    NASA Astrophysics Data System (ADS)

    Davidson, Mark

    2015-05-01

    A recent theoretical explanation for observed anomalous low energy nuclear phenomena which have puzzled physicists for many years is expanded on. Based on covariant relativistic quantum mechanics and historical time wave equations, it explains a large number of observed anomalous effects by supposing that nuclear masses can vary in “nuclear active environments” in condensed matter settings. The modified quantum wave equation originally introduced by Fock and Stueckelberg in the 1930s with significant enhancements up to the present by Horwitz and others prove that variable masses are compatible with the principles of both quantum mechanics and relativity. They can explain all of these effects by modifying the kinematic constraints of the reaction, enhancing electron screening and quantum tunneling rates, and allowing for resonant tunneling. Some previous results are recounted, and experimental evidence based on variable radioactive decay rates and other evidence for variable masses is presented which adds some new potential support for this theory.

  6. A particle-field Hamiltonian in relativistic quantum electrodynamics

    NASA Astrophysics Data System (ADS)

    Arai, Asao

    2000-07-01

    We mathematically analyze a Hamiltonian Hτ(V,g) of a Dirac particle—a relativistic charged particle with spin 1/2—minimally coupled to the quantized radiation field, acting in the Hilbert space F≔[⊕4L2(R3)]⊗Frad, where Frad is the Fock space of the quantized radiation field in the Coulomb gauge, V is an external potential in which the Dirac particle moves, g is a photon-momentum cutoff function in the interaction between the Dirac particle and the quantized radiation field, and τ∈R is a deformation parameter connecting the Hamiltonian with the "dipole approximation" (τ=0) and the original Hamiltonian (τ=1). We first discuss the self-adjointness problem of Hτ(V,g). Then we consider Hτ≔Hτ(0,g), the Hamiltonian without the external potential. It is shown that, under a general condition on g, the closure of Hτ is unitarily equivalent to a direct integral ∫R3⊕Hτ(p)¯dp with a fiber Hamiltonian Hτ(p) acting in the four direct sum ⊕4Frad of Frad, physically the polaron Hamiltonian of the Dirac particle with total momentum p∈R3.

  7. Excitation of azimuthal surface modes by relativistic flows of electrons in the high-frequency range

    SciTech Connect

    Girka, V. O.; Girka, I. O.; Pavlenko, I. V.

    2011-05-15

    Excitation of extraordinarily polarized azimuthal surface eigenwaves is shown to be possible in the frequency range above the upper hybrid resonance in waveguides with metal walls which are partially filled by cold magnetoactive plasma. Interaction of these waves with flows of electrons which rotate around the plasma column in the narrow gap separating the plasma from the wall of the waveguide is studied. Conditions of resonant interaction of the beam with the mentioned high-frequency azimuthal surface waves are shown by numerical methods to be reachable ones in the case of enough strong external magnetic fields without passing to the field of ultra-relativistic velocities of the beam.

  8. Orbital analysis of LAGEOS and LAGEOS II laser ranged satellites: relativistic effects and geophysical issues

    SciTech Connect

    Peron, Roberto

    2005-03-16

    We present here the results of a recent analysis of LAGEOS and LAGEOS II laser range data. The higher accuracy in determining the orbits of these satellites makes it possible to see very tiny relativistic effects like frame-dragging and a wide variety of other phenomena at work. In particular, it is apparent the need of better understanding some effects of non-gravitational origin. The importance of these orbital fits as a geophysical probe is also stressed with a particular example. The analysis is carried out with GEODYN II Software, whose broad structure and use is described.

  9. Orbital analysis of LAGEOS and LAGEOS II laser ranged satellites: relativistic effects and geophysical issues

    NASA Astrophysics Data System (ADS)

    Peron, Roberto

    2005-03-01

    We present here the results of a recent analysis of LAGEOS and LAGEOS II laser range data. The higher accuracy in determining the orbits of these satellites makes it possible to see very tiny relativistic effects like frame-dragging and a wide variety of other phenomena at work. In particular, it is apparent the need of better understanding some effects of non-gravitational origin. The importance of these orbital fits as a geophysical probe is also stressed with a particular example. The analysis is carried out with GEODYN II Software, whose broad structure and use is described.

  10. Covariant spectator theory of $np$ scattering:\\\\ Effective range expansions and relativistic deuteron wave functions

    SciTech Connect

    Franz Gross, Alfred Stadler

    2010-09-01

    We present the effective range expansions for the 1S0 and 3S1 scattering phase shifts, and the relativistic deuteron wave functions that accompany our recent high precision fits (with \\chi^2/N{data} \\simeq 1) to the 2007 world np data below 350 MeV. The wave functions are expanded in a series of analytical functions (with the correct asymptotic behavior at both large and small arguments) that can be Fourier-transformed from momentum to coordinate space and are convenient to use in any application. A fortran subroutine to compute these wave functions can be obtained from the authors.

  11. Thermodynamics of Quantum Gases for the Entire Range of Temperature

    ERIC Educational Resources Information Center

    Biswas, Shyamal; Jana, Debnarayan

    2012-01-01

    We have analytically explored the thermodynamics of free Bose and Fermi gases for the entire range of temperature, and have extended the same for harmonically trapped cases. We have obtained approximate chemical potentials for the quantum gases in closed forms of temperature so that the thermodynamic properties of the quantum gases become…

  12. Schrödinger problem, Lévy processes, and noise in relativistic quantum mechanics

    NASA Astrophysics Data System (ADS)

    Garbaczewski, Piotr; Klauder, John R.; Olkiewicz, Robert

    1995-05-01

    The main purpose of the paper is an essentially probabilistic analysis of relativistic quantum mechanics. It is based on the assumption that whenever probability distributions arise, there exists a stochastic process that is either responsible for the temporal evolution of a given measure or preserves the measure in the stationary case. Our departure point is the so-called Schrödinger problem of probabilistic evolution, which provides for a unique Markov stochastic interpolation between any given pair of boundary probability densities for a process covering a fixed, finite duration of time, provided we have decided a priori what kind of primordial dynamical semigroup transition mechanism is involved. In the nonrelativistic theory, including quantum mechanics, Feynman-Kac-like kernels are the building blocks for suitable transition probability densities of the process. In the standard ``free'' case (Feynman-Kac potential equal to zero) the familiar Wiener noise is recovered. In the framework of the Schrödinger problem, the ``free noise'' can also be extended to any infinitely divisible probability law, as covered by the Lévy-Khintchine formula. Since the relativistic Hamiltonians ||∇|| and √-Δ+m2 -m are known to generate such laws, we focus on them for the analysis of probabilistic phenomena, which are shown to be associated with the relativistic wave (D'Alembert) and matter-wave (Klein-Gordon) equations, respectively. We show that such stochastic processes exist and are spatial jump processes. In general, in the presence of external potentials, they do not share the Markov property, except for stationary situations. A concrete example of the pseudodifferential Cauchy-Schrödinger evolution is analyzed in detail. The relativistic covariance of related wave equations is exploited to demonstrate how the associated stochastic jump processes comply with the principles of special relativity.

  13. On a two-pass scheme without a faraday mirror for free-space relativistic quantum cryptography

    SciTech Connect

    Kravtsov, K. S.; Radchenko, I. V.; Korol'kov, A. V.; Kulik, S. P.; Molotkov, S. N.

    2013-05-15

    The stability of destructive interference independent of the input polarization and the state of a quantum communication channel in fiber optic systems used in quantum cryptography plays a principal role in providing the security of communicated keys. A novel optical scheme is proposed that can be used both in relativistic quantum cryptography for communicating keys in open space and for communicating them over fiber optic lines. The scheme ensures stability of destructive interference and admits simple automatic balancing of a fiber interferometer.

  14. Certified randomness from a two-level system in a relativistic quantum field

    NASA Astrophysics Data System (ADS)

    Thinh, Le Phuc; Bancal, Jean-Daniel; Martín-Martínez, Eduardo

    2016-08-01

    Randomness is an indispensable resource in modern science and information technology. Fortunately, an experimentally simple procedure exists to generate randomness with well-characterized devices: measuring a quantum system in a basis complementary to its preparation. Towards realizing this goal one may consider using atoms or superconducting qubits, promising candidates for quantum information processing. However, their unavoidable interaction with the electromagnetic field affects their dynamics. At large time scales, this can result in decoherence. Smaller time scales in principle avoid this problem, but may not be well analyzed under the usual rotating wave and single mode approximation (RWA and SMA) which break the relativistic nature of quantum field theory. Here, we use a fully relativistic analysis to quantify the information that an adversary with access to the field could get on the result of an atomic measurement. Surprisingly, we find that the adversary's guessing probability is not minimized for atoms initially prepared in the ground state (an intuition derived from the RWA and SMA model).

  15. Quantum speed limit for a relativistic electron in a uniform magnetic field

    NASA Astrophysics Data System (ADS)

    Villamizar, D. V.; Duzzioni, E. I.

    2015-10-01

    We analyze the influence of relativistic effects on the minimum evolution time between two orthogonal states of a quantum system. Defining the initial state as a homogeneous superposition between two Hamiltonian eigenstates of an electron in a uniform magnetic field, we obtain a relation between the minimum evolution time and the displacement of the mean radial position of the electron wave packet. The quantum speed limit time is calculated for an electron dynamics described by Dirac and Schrödinger-Pauli equations considering different parameters, such as the strength of magnetic field and the linear momentum of the electron in the axial direction. We highlight that when the electron undergoes a region with extremely strong magnetic field the relativistic and nonrelativistic dynamics differ substantially, so that the description given by the Schrödinger-Pauli equation enables the electron to travel faster than c , which is prohibited by Einstein's theory of relativity. This approach allows a connection between the abstract Hilbert space and the space-time coordinates, besides the identification of the most appropriate quantum dynamics used to describe the electron motion.

  16. Generalized Lagrangian-Path Representation of Non-Relativistic Quantum Mechanics

    NASA Astrophysics Data System (ADS)

    Tessarotto, Massimo; Cremaschini, Claudio

    2016-08-01

    In this paper a new trajectory-based representation to non-relativistic quantum mechanics is formulated. This is ahieved by generalizing the notion of Lagrangian path (LP) which lies at the heart of the deBroglie-Bohm " pilot-wave" interpretation. In particular, it is shown that each LP can be replaced with a statistical ensemble formed by an infinite family of stochastic curves, referred to as generalized Lagrangian paths (GLP). This permits the introduction of a new parametric representation of the Schrödinger equation, denoted as GLP-parametrization, and of the associated quantum hydrodynamic equations. The remarkable aspect of the GLP approach presented here is that it realizes at the same time also a new solution method for the N-body Schrödinger equation. As an application, Gaussian-like particular solutions for the quantum probability density function (PDF) are considered, which are proved to be dynamically consistent. For them, the Schrödinger equation is reduced to a single Hamilton-Jacobi evolution equation. Particular solutions of this type are explicitly constructed, which include the case of free particles occurring in 1- or N-body quantum systems as well as the dynamics in the presence of suitable potential forces. In all these cases the initial Gaussian PDFs are shown to be free of the spreading behavior usually ascribed to quantum wave-packets, in that they exhibit the characteristic feature of remaining at all times spatially-localized.

  17. Covariant spectator theory of np scattering: Effective range expansions and relativistic deuteron wave functions

    SciTech Connect

    Gross, Franz; Stadler, Alfred

    2010-09-15

    We present the effective range expansions for the {sup 1}S{sub 0} and {sup 3}S{sub 1} scattering phase shifts, and the relativistic deuteron wave functions that accompany our recent high precision fits (with {chi}{sup 2}/N{sub data{approx_equal}}1) to the 2007 world np data below 350 MeV. The wave functions are expanded in a series of analytical functions (with the correct asymptotic behavior at both large and small arguments) that can be Fourier-transformed from momentum to coordinate space and are convenient to use in any application. A fortran subroutine to compute these wave functions can be obtained from the authors.

  18. Notes on Translational and Rotational Properties of Tensor Fields in Relativistic Quantum Mechanics

    NASA Astrophysics Data System (ADS)

    Dvoeglazov, V. V.

    Recently, several discussions on the possible observability of 4-vector fields have been published in literature. Furthermore, several authors recently claimed existence of the helicity=0 fundamental field. We re-examine the theory of antisymmetric tensor fields and 4-vector potentials. We study the massless limits. In fact, a theoretical motivation for this venture is the old papers of Ogievetskiĭ and Polubarinov, Hayashi, and Kalb and Ramond. Ogievetskiĭ and Polubarinov proposed the concept of the notoph, whose helicity properties are complementary to those of the photon. We analyze the quantum field theory with taking into account mass dimensions of the notoph and the photon. It appears to be possible to describe both photon and notoph degrees of freedom on the basis of the modified Bargmann-Wigner formalism for the symmetric second-rank spinor. Next, we proceed to derive equations for the symmetric tensor of the second rank on the basis of the Bargmann-Wigner formalism in a straightforward way. The symmetric multispinor of the fourth rank is used. Due to serious problems with the interpretation of the results obtained on using the standard procedure we generalize it and obtain the spin-2 relativistic equations, which are consistent with the general relativity. Thus, in fact we deduced the gravitational field equations from relativistic quantum mechanics. The relations of this theory with the scalar-tensor theories of gravitation and f(R) are discussed. Particular attention has been paid to the correct definitions of the energy-momentum tensor and other Nöther currents in the electromagnetic theory, the relativistic theory of gravitation, the general relativity, and their generalizations. We estimate possible interactions, fermion-notoph, graviton-notoph, photon-notoph, and we conclude that they can probably be seen in experiments in the next few years.

  19. Proof of the spin-statistics theorem in the relativistic regimen by Weyl’s conformal quantum mechanics

    NASA Astrophysics Data System (ADS)

    de Martini, Francesco; Santamato, Enrico

    2016-04-01

    The traditional standard theory of quantum mechanics is unable to solve the spin-statistics problem, i.e. to justify the utterly important “Pauli Exclusion Principle” but by the adoption of the complex standard relativistic quantum field theory. In a recent paper [E. Santamato and F. D. De Martini, Found. Phys. 45 (2015) 858] we presented a complete proof of the spin-statistics problem in the nonrelativistic approximation on the basis of the “Conformal Quantum Geometrodynamics” (CQG). In this paper, by the same theory, the proof of the spin-statistics theorem (SST) is extended to the relativistic domain in the scenario of curved spacetime. No relativistic quantum field operators are used in the present proof and the particle exchange properties are drawn from rotational invariance rather than from Lorentz invariance. Our relativistic approach allows to formulate a manifestly step-by-step Weyl gauge invariant theory and to emphasize some fundamental aspects of group theory in the demonstration. As in the nonrelativistic case, we find once more that the “intrinsic helicity” of the elementary particles enters naturally into play. It is therefore this property, not considered in the standard quantum mechanics (SQM), which determines the correct spin-statistics connection observed in Nature.

  20. A statistical model for relativistic quantum fluids interacting with an intense electromagnetic wave

    NASA Astrophysics Data System (ADS)

    Mahajan, Swadesh M.; Asenjo, Felipe A.

    2016-05-01

    A statistical model for relativistic quantum fluids interacting with an arbitrary amplitude circularly polarized electromagnetic wave is developed in two steps. First, the energy spectrum and the wave function for a quantum particle (Klein Gordon and Dirac) embedded in the electromagnetic wave are calculated by solving the appropriate eigenvalue problem. The energy spectrum is anisotropic in the momentum K and reflects the electromagnetic field through the renormalization of the rest mass m to M =√{m2+q2A2 } . Based on this energy spectrum of this quantum particle plus field combination (QPF), a statistical mechanics model of the quantum fluid made up of these weakly interacting QPF is developed. Preliminary investigations of the formalism yield highly interesting results—a new scale for temperature, and fundamental modification of the dispersion relation of the electromagnetic wave. It is expected that this formulation could, inter alia, uniquely advance our understanding of laboratory as well as astrophysical systems where one encounters arbitrarily large electromagnetic fields.

  1. Quantum tagging: Authenticating location via quantum information and relativistic signaling constraints

    SciTech Connect

    Kent, Adrian; Munro, William J.; Spiller, Timothy P.

    2011-07-15

    We define the task of quantum tagging, that is, authenticating the classical location of a classical tagging device by sending and receiving quantum signals from suitably located distant sites, in an environment controlled by an adversary whose quantum information processing and transmitting power is unbounded. We define simple security models for this task and briefly discuss alternatives. We illustrate the pitfalls of naive quantum cryptographic reasoning in this context by describing several protocols which at first sight appear unconditionally secure but which, as we show, can in fact be broken by teleportation-based attacks. We also describe some protocols which cannot be broken by these specific attacks, but do not prove they are unconditionally secure. We review the history of quantum tagging protocols, and show that protocols previously proposed by Malaney and Chandran et al. are provably insecure.

  2. Eigenenergies of a Relativistic Particle in an Infinite Range Linear Potential Using WKB Method

    ERIC Educational Resources Information Center

    Shivalingaswamy, T.; Kagali, B. A.

    2011-01-01

    Energy eigenvalues for a non-relativistic particle in a linear potential well are available. In this paper we obtain the eigenenergies for a relativistic spin less particle in a similar potential using an extension of the well-known WKB method treating the potential as the time component of a four-vector potential. Since genuine bound states do…

  3. Quench dynamics in long-range interacting quantum systems

    NASA Astrophysics Data System (ADS)

    Gong, Zhexuan

    2016-05-01

    A distinctive feature of atomic, molecular, and optical systems is that interactions between particles are often long-ranged. Control techniques from quantum optics often allow one to tune the pattern of these long-range interactions, creating an entirely new degree of freedom, absent in typical condensed matter systems. These tunable long-range interactions can result in very different far-from-equilibrium dynamics compared to systems with only short-range interactions. In the first half of the talk, I will describe how very general types of long-range interactions can qualitatively change the entanglement and correlation growth shortly after a quantum quench. In the second half of the talk I will show that, at longer times, long-range interactions can lead to exotic quasi-stationary states and dynamical phase transitions. These theoretical ideas have been explored in recent trapped-ion experiments, and connections to these experiments will be emphasized in both parts of the talk.

  4. Nonlinear quantum theory of stimulated Cherenkov radiation of transverse electromagnetic waves from a low-density relativistic electron beam in a dielectric medium

    SciTech Connect

    Bobylev, Yu. B.; Kuzelev, M. V.

    2012-06-15

    A nonlinear quantum theory of stimulated Cherenkov radiation of transverse electromagnetic waves from a low-density relativistic electron beam in an isotropic dielectric medium is presented. A quantum model based on the Klein-Gordon equation is used. The growth rates of beam instabilities caused by the effect of stimulated Cherenkov radiation have been determined in the linear approximation. Mechanisms of the nonlinear saturation of relativistic quantum Cherenkov beam instabilities have been analyzed and the corresponding analytical solutions have been obtained.

  5. Quantum-electrodynamical birefringence vanishing in a thermal relativistic pair plasma.

    PubMed

    Huang, Y S

    2015-01-01

    Quantum electrodynamical (QED) birefringence in a thermal relativistic pair plasma with the presence of the strong crossed field: E0 ⊥ B0, is proposed and investigated. We clarify the coupling relationship and competition between the QED effect and the plasma collective effect and find the critical condition that makes the birefringence vanish. In a relative weak electromagnetic field, the birefringence is dominated by the coupling of the QED-effect, the collective effect and the E0 × B0 drift effect. In a relative strong electromagnetic field, we obtain the formulations stating the competition between the QED effect and the collective effect and then the critical conditions so that they are canceled with each other and the birefringence vanishes. With our results, a new possible scheme is proposed to estimate the thickness of the magnetosphere in a millisecond pulsar and the plasma density of a pulsar, if the magnetic field is known beforehand. PMID:26522493

  6. Quantum-electrodynamical birefringence vanishing in a thermal relativistic pair plasma

    PubMed Central

    Huang, Y. S.

    2015-01-01

    Quantum electrodynamical (QED) birefringence in a thermal relativistic pair plasma with the presence of the strong crossed field: , is proposed and investigated. We clarify the coupling relationship and competition between the QED effect and the plasma collective effect and find the critical condition that makes the birefringence vanish. In a relative weak electromagnetic field, the birefringence is dominated by the coupling of the QED-effect, the collective effect and the drift effect. In a relative strong electromagnetic field, we obtain the formulations stating the competition between the QED effect and the collective effect and then the critical conditions so that they are canceled with each other and the birefringence vanishes. With our results, a new possible scheme is proposed to estimate the thickness of the magnetosphere in a millisecond pulsar and the plasma density of a pulsar, if the magnetic field is known beforehand. PMID:26522493

  7. Matrix continued fraction approach to the relativistic quantum mechanical spin-zero Feshbach-Villars equations

    NASA Astrophysics Data System (ADS)

    Brown, Natalie

    In this thesis we solve the Feshbach-Villars equations for spin-zero particles through use of matrix continued fractions. The Feshbach-Villars equations are derived from the Klein-Gordon equation and admit, for the Coulomb potential on an appropriate basis, a Hamiltonian form that has infinite symmetric band-matrix structure. The corresponding representation of the Green's operator of such a matrix can be given as a matrix continued fraction. Furthermore, we propose a finite dimensional representation for the potential operator such that it retains some information about the whole Hilbert space. Combining these two techniques, we are able to solve relativistic quantum mechanical problems of a spin-zero particle in a Coulomb-like potential with a high level of accuracy.

  8. Comment on "Stationary self-focusing of Gaussian laser beam in relativistic thermal quantum plasma" [Phys. Plasmas 20, 072703 (2013)

    NASA Astrophysics Data System (ADS)

    Habibi, M.; Ghamari, F.

    2014-06-01

    Patil and Takale in their recent article [Phys. Plasmas 20, 072703 (2013)], by evaluating the quantum dielectric response in thermal quantum plasma, have modeled the relativistic self-focusing of Gaussian laser beam in a plasma. We have found that there are some important shortcomings and fundamental mistakes in Patil and Takale [Phys. Plasmas 20, 072703 (2013)] that we give a brief description about them and refer readers to important misconception about the use of the Fermi temperature in quantum plasmas, appearing in Patil and Takale [Phys. Plasmas 20, 072703 (2013)].

  9. PREFACE: IARD 2010: The 7th Biennial Conference on Classical and Quantum Relativistic Dynamics of Particles and Fields

    NASA Astrophysics Data System (ADS)

    Horwitz, Lawrence; Hu, Bei-Lok; Lee, Da-Shin; Gill, Tepper; Land, Martin

    2011-12-01

    Although the subject of relativistic dynamics has been explored from both classical and quantum mechanical points of view since the work of Einstein and Dirac, its most striking development has been in the framework of quantum field theory. The very accurate calculations of spectral and scattering properties, for example, of the anamolous magnetic moment of the electron and the Lamb shift in quantum electrodynamics, and many qualitative features of the strong and electroweak interactions, demonstrate the very great power of description achieved in this framework. Yet, many fundamental questions remain to be clarified, such as the structure of classical realtivistic dynamical theories on the level of Hamilton and Lagrange in Minkowski space as well as on the curved manifolds of general relativity. There moreover remains the important question of the covariant classical description of systems at high energy for which particle production effects are not large, such as discussed in Synge's book, The Relativistic Gas, and in Balescu's book on relativistic statistical mechanics. In recent years, the study of high energy plasmas and heavy ion collisions has emphasized the importance of developing the techniques of relativistic mechanics. The results of Linder et al (Phys. Rev. Lett. 95 0040401 (2005)) as well as the more recent work of Palacios et al (Phys. Rev. Lett. 103 253001 (2009)) and others, have shown that there must be a quantum theory with coherence in time. Such a theory, manifestly covariant under the transformations of special relativity with an invariant evolution parameter, such as that of Stueckelberg (Helv. Phys. Acta 14 322, 588 (1941); 15 23 (1942); see also R P Feynman Phys. Rev. 80 4401 and J S Schwinger Phys. Rev. 82 664 (1951)) could provide a suitable basis for the study of such questions, as well as many others for which the application of the standard methods of quantum field theory are difficult to manage, involving, in particular, local

  10. Fractional quantum mechanics on networks: Long-range dynamics and quantum transport

    NASA Astrophysics Data System (ADS)

    Riascos, A. P.; Mateos, José L.

    2015-11-01

    In this paper we study the quantum transport on networks with a temporal evolution governed by the fractional Schrödinger equation. We generalize the dynamics based on continuous-time quantum walks, with transitions to nearest neighbors on the network, to the fractional case that allows long-range displacements. By using the fractional Laplacian matrix of a network, we establish a formalism that combines a long-range dynamics with the quantum superposition of states; this general approach applies to any type of connected undirected networks, including regular, random, and complex networks, and can be implemented from the spectral properties of the Laplacian matrix. We study the fractional dynamics and its capacity to explore the network by means of the transition probability, the average probability of return, and global quantities that characterize the efficiency of this quantum process. As a particular case, we explore analytically these quantities for circulant networks such as rings, interacting cycles, and complete graphs.

  11. Fractional quantum mechanics on networks: Long-range dynamics and quantum transport.

    PubMed

    Riascos, A P; Mateos, José L

    2015-11-01

    In this paper we study the quantum transport on networks with a temporal evolution governed by the fractional Schrödinger equation. We generalize the dynamics based on continuous-time quantum walks, with transitions to nearest neighbors on the network, to the fractional case that allows long-range displacements. By using the fractional Laplacian matrix of a network, we establish a formalism that combines a long-range dynamics with the quantum superposition of states; this general approach applies to any type of connected undirected networks, including regular, random, and complex networks, and can be implemented from the spectral properties of the Laplacian matrix. We study the fractional dynamics and its capacity to explore the network by means of the transition probability, the average probability of return, and global quantities that characterize the efficiency of this quantum process. As a particular case, we explore analytically these quantities for circulant networks such as rings, interacting cycles, and complete graphs.

  12. Fractional quantum mechanics on networks: Long-range dynamics and quantum transport.

    PubMed

    Riascos, A P; Mateos, José L

    2015-11-01

    In this paper we study the quantum transport on networks with a temporal evolution governed by the fractional Schrödinger equation. We generalize the dynamics based on continuous-time quantum walks, with transitions to nearest neighbors on the network, to the fractional case that allows long-range displacements. By using the fractional Laplacian matrix of a network, we establish a formalism that combines a long-range dynamics with the quantum superposition of states; this general approach applies to any type of connected undirected networks, including regular, random, and complex networks, and can be implemented from the spectral properties of the Laplacian matrix. We study the fractional dynamics and its capacity to explore the network by means of the transition probability, the average probability of return, and global quantities that characterize the efficiency of this quantum process. As a particular case, we explore analytically these quantities for circulant networks such as rings, interacting cycles, and complete graphs. PMID:26651751

  13. Five-dimensional Hamiltonian-Jacobi approach to relativistic quantum mechanics

    SciTech Connect

    Rose, Harald

    2003-12-11

    A novel theory is outlined for describing the dynamics of relativistic electrons and positrons. By introducing the Lorentz-invariant universal time as a fifth independent variable, the Hamilton-Jacobi formalism of classical mechanics is extended from three to four spatial dimensions. This approach allows one to incorporate gravitation and spin interactions in the extended five-dimensional Lagrangian in a covariant form. The universal time has the function of a hidden Bell parameter. By employing the method of variation with respect to the four coordinates of the particle and the components of the electromagnetic field, the path equation and the electromagnetic field produced by the charge and the spin of the moving particle are derived. In addition the covariant equations for the dynamics of the components of the spin tensor are obtained. These equations can be transformed to the familiar BMT equation in the case of homogeneous electromagnetic fields. The quantization of the five-dimensional Hamilton-Jacobi equation yields a five-dimensional spinor wave equation, which degenerates to the Dirac equation in the stationary case if we neglect gravitation. The quantity which corresponds to the probability density of standard quantum mechanics is the four-dimensional mass density which has a real physical meaning. By means of the Green method the wave equation is transformed into an integral equation enabling a covariant relativistic path integral formulation. Using this approach a very accurate approximation for the four-dimensional propagator is derived. The proposed formalism makes Dirac's hole theory obsolete and can readily be extended to many particles.

  14. Robust Multiple-Range Coherent Quantum State Transfer

    NASA Astrophysics Data System (ADS)

    Chen, Bing; Peng, Yan-Dong; Li, Yong; Qian, Xiao-Feng

    2016-07-01

    We propose a multiple-range quantum communication channel to realize coherent two-way quantum state transport with high fidelity. In our scheme, an information carrier (a qubit) and its remote partner are both adiabatically coupled to the same data bus, i.e., an N-site tight-binding chain that has a single defect at the center. At the weak interaction regime, our system is effectively equivalent to a three level system of which a coherent superposition of the two carrier states constitutes a dark state. The adiabatic coupling allows a well controllable information exchange timing via the dark state between the two carriers. Numerical results show that our scheme is robust and efficient under practically inevitable perturbative defects of the data bus as well as environmental dephasing noise.

  15. Robust Multiple-Range Coherent Quantum State Transfer

    PubMed Central

    Chen, Bing; Peng, Yan-Dong; Li, Yong; Qian, Xiao-Feng

    2016-01-01

    We propose a multiple-range quantum communication channel to realize coherent two-way quantum state transport with high fidelity. In our scheme, an information carrier (a qubit) and its remote partner are both adiabatically coupled to the same data bus, i.e., an N-site tight-binding chain that has a single defect at the center. At the weak interaction regime, our system is effectively equivalent to a three level system of which a coherent superposition of the two carrier states constitutes a dark state. The adiabatic coupling allows a well controllable information exchange timing via the dark state between the two carriers. Numerical results show that our scheme is robust and efficient under practically inevitable perturbative defects of the data bus as well as environmental dephasing noise. PMID:27364891

  16. Relativistic Anandan quantum phase and the Aharonov-Casher effect under Lorentz symmetry breaking effects in the cosmic string spacetime

    NASA Astrophysics Data System (ADS)

    Bakke, K.; Furtado, C.; Belich, H.

    2016-09-01

    From the modified Maxwell theory coupled to gravity, we establish a possible scenario of the violation of the Lorentz symmetry and write an effective metric for the cosmic string spacetime. Then, we investigate the arising of an analogue of the Anandan quantum phase for a relativistic Dirac neutral particle with a permanent magnetic dipole moment in the cosmic string spacetime under Lorentz symmetry breaking effects. Besides, we analyse the influence of the effects of the Lorentz symmetry violation and the topology of the defect on the Aharonov-Casher geometric quantum phase in the nonrelativistic limit.

  17. Long range correlations and the soft ridge in relativistic nuclear collisions

    SciTech Connect

    Gavin, Sean; Moschelli, George; McLerran, Larry

    2009-05-15

    Relativistic Heavy Ion Collider experiments exhibit correlations peaked in relative azimuthal angle and extended in rapidity. Called the ridge, this peak occurs both with and without a jet trigger. We argue that the untriggered ridge arises when particles formed by flux tubes in an early Glasma stage later manifest transverse flow. Combining a blast wave model of flow fixed by single-particle spectra with a simple description of the Glasma, we find excellent agreement with current data.

  18. Long range correlations and the soft ridge in relativistic nuclear collisions

    SciTech Connect

    McLerran, L.; Gavin, S., Moschelli, G.

    2009-05-19

    Relativistic Heavy Ion Collider experiments exhibit correlations peaked in relative azimuthal angle and extended in rapidity. Called the ridge, this peak occurs both with and without a jet trigger. We argue that the untriggered ridge arises when particles formed by flux tubes in an early Glasma stage later manifest transverse flow. Combining a blast wave model of flow fixed by single-particle spectra with a simple description of the Glasma, we find excellent agreement with current data.

  19. Relativistic causality and quantum-mechanical states in the Fermi problem

    NASA Astrophysics Data System (ADS)

    Compagno, G.; Palma, G. M.; Passante, R.; Persico, F.

    1995-09-01

    We discuss the validity of relativistic causality in the excitation exchange of a pair of atoms in vacuo. This is usually described as the Fermi problem. The atoms are modeled as two-level systems and their coupling with the electromagnetic field is taken in the multipolar scheme and in the electric dipole approximation. The atomic dynamics is determined by a solution of the Heisenberg equations for the atomic pseudospin operators Sz, S+ and S-, which is valid for times smaller than the spontaneous decay time. We show that for each atom this dynamics is manifestly casual, because it is independent of the presence of the other atom for times up to t = R/c, where R is the interatomic distance. Since this treatment is only in terms of operators and does not make any reference to states, we conclude that causality is a fundamental feature of the Fermi problem which does not depend of the quantum-mechanical state of the atom-field system.

  20. Quantum radiation reaction force on a one-dimensional cavity with two relativistic moving mirrors

    SciTech Connect

    Alves, Danilo T.; Granhen, Edney R.; Pires, Wagner P.

    2010-08-15

    We consider a real massless scalar field inside a cavity with two moving mirrors in a two-dimensional spacetime, satisfying the Dirichlet boundary condition at the instantaneous position of the boundaries, for arbitrary and relativistic laws of motion. Considering vacuum as the initial field state, we obtain formulas for the exact value of the energy density of the field and the quantum force acting on the boundaries, which extend results found in previous papers [D. T. Alves, E. R. Granhen, H. O. Silva, and M. G. Lima, Phys. Rev. D 81, 025016 (2010); L. Li and B.-Z. Li, Phys. Lett. A 300, 27 (2002); L. Li and B.-Z. Li, Chin. Phys. Lett. 19, 1061 (2002); L. Li and B.-Z. Li, Acta Phys. Sin. 52, 2762 (2003); C. K. Cole and W. C. Schieve, Phys. Rev. A 64, 023813 (2001)]. For the particular cases of a cavity with just one moving boundary, nonrelativistic velocities, or in the limit of infinity length of the cavity (a single mirror), our results coincide with those found in the literature.

  1. PREFACE: IARD 2012: 8th Biennial Conference on Classical and Quantum Relativistic Dynamics of Particles and Fields

    NASA Astrophysics Data System (ADS)

    Horwitz, L. P.; Land, Martin C.; Gill, Tepper; Lusanna, Luca; Salucci, Paolo

    2013-04-01

    Although the subject of relativistic dynamics has been explored, from both classical and quantum mechanical points of view, since the work of Einstein and Dirac, its most striking development has been in the framework of quantum field theory. The very accurate calculations of spectral and scattering properties, for example, of the anomalous magnetic moment of the electron and the Lamb shift in quantum electrodynamics, and many qualitative features of the strong and electroweak interactions, demonstrate the very great power of description achieved in this framework. Yet, many fundamental questions remain to be clarified, such as the structure of classical relativistic dynamical theories on the level of Hamilton and Lagrange in Minkowski space as well as on the curved manifolds of general relativity. There moreover remains the important question of the covariant classical description of systems at high energy for which particle production effects are not large, such as discussed in Synge's book, The Relativistic Gas, and in Balescu's book on relativistic statistical mechanics. In recent years, the study of high energy plasmas and heavy ion collisions has emphasized the importance of developing the techniques of relativistic mechanics. The results of Lindner et al [Physical Review Letters 95 0040401 (2005)] as well as the more recent proposal of Palacios et al [Phys. Rev. Lett. 103 253001 (2009)] and others, have shown that there must be a quantum theory with coherence in time. Such a theory, manifestly covariant under the transformations of special relativity with an invariant evolution parameter, such as that of Stueckelberg [Helv. Phys. Acta 14 322, 588 (1941); 15 23 (1942); see also R P Feynman Phys. Rev. 80 4401 and J S Schwinger Phys. Rev. 82 664 (1951)] could provide a suitable basis for the study of such questions, as well as many others for which the application of the standard methods of quantum field theory are difficult to manage, involving, in particular

  2. Relativistic geometric quantum phases from the Lorentz symmetry violation effects in the CPT-even gauge sector of Standard Model Extension

    NASA Astrophysics Data System (ADS)

    Bakke, K.; Belich, H.

    2015-11-01

    We discuss the appearance of geometric quantum phases for a Dirac neutral particle in the context of relativistic quantum mechanics based on possible scenarios of the Lorentz symmetry violation tensor background in the CPT-even gauge sector of Standard Model Extension. We assume that the Lorentz symmetry breaking is determined by a tensor background given by (KF)μναβ, then, relativistic analogues of the Anandan quantum phase [J. Anandan, Phys. Lett. A 138, 347 (1989)] are obtained based on the parity-even and parity-odd sectors of the tensor (KF)μναβ.

  3. Response to “Comment on ‘Stationary self-focusing of Gaussian laser beam in relativistic thermal quantum plasma’” [Phys. Plasmas 21, 064701 (2014)

    SciTech Connect

    Patil, S. D.; Takale, M. V.

    2014-06-15

    Habibi and Ghamari have presented a Comment on our paper [Phys. Plasmas 20, 072703 (2013)] by examining quantum dielectric response in thermal quantum plasma. They have modeled the relativistic self-focusing of Gaussian laser beam in cold and warm quantum plasmas and reported that self-focusing length does not change in both situations. In this response, we have reached the following important conclusions about the comment itself.

  4. Electrostatic solitary waves in a quantum plasma with relativistically degenerate electrons

    NASA Astrophysics Data System (ADS)

    Masood, W.; Eliasson, B.

    2011-03-01

    A model for nonlinear ion waves in an unmagnetized plasma with relativistically degenerate electrons and cold fluid ions is presented here. The inertia is given here by the ion mass while the restoring force is provided by the relativistic electron degeneracy pressure, and the dispersion is due to the deviation from charge neutrality. A nonlinear Korteweg-de Vries equation is derived for small but finite amplitude waves and is used to study the properties of localized ion acoustic solitons for parameters relevant for dense astrophysical objects such as white dwarf stars. Different degrees of relativistic electron degeneracy are discussed and compared.

  5. PREFACE: IARD 2012: 8th Biennial Conference on Classical and Quantum Relativistic Dynamics of Particles and Fields

    NASA Astrophysics Data System (ADS)

    Horwitz, L. P.; Land, Martin C.; Gill, Tepper; Lusanna, Luca; Salucci, Paolo

    2013-04-01

    Although the subject of relativistic dynamics has been explored, from both classical and quantum mechanical points of view, since the work of Einstein and Dirac, its most striking development has been in the framework of quantum field theory. The very accurate calculations of spectral and scattering properties, for example, of the anomalous magnetic moment of the electron and the Lamb shift in quantum electrodynamics, and many qualitative features of the strong and electroweak interactions, demonstrate the very great power of description achieved in this framework. Yet, many fundamental questions remain to be clarified, such as the structure of classical relativistic dynamical theories on the level of Hamilton and Lagrange in Minkowski space as well as on the curved manifolds of general relativity. There moreover remains the important question of the covariant classical description of systems at high energy for which particle production effects are not large, such as discussed in Synge's book, The Relativistic Gas, and in Balescu's book on relativistic statistical mechanics. In recent years, the study of high energy plasmas and heavy ion collisions has emphasized the importance of developing the techniques of relativistic mechanics. The results of Lindner et al [Physical Review Letters 95 0040401 (2005)] as well as the more recent proposal of Palacios et al [Phys. Rev. Lett. 103 253001 (2009)] and others, have shown that there must be a quantum theory with coherence in time. Such a theory, manifestly covariant under the transformations of special relativity with an invariant evolution parameter, such as that of Stueckelberg [Helv. Phys. Acta 14 322, 588 (1941); 15 23 (1942); see also R P Feynman Phys. Rev. 80 4401 and J S Schwinger Phys. Rev. 82 664 (1951)] could provide a suitable basis for the study of such questions, as well as many others for which the application of the standard methods of quantum field theory are difficult to manage, involving, in particular

  6. PREFACE: IARD 2010: The 7th Biennial Conference on Classical and Quantum Relativistic Dynamics of Particles and Fields

    NASA Astrophysics Data System (ADS)

    Horwitz, Lawrence; Hu, Bei-Lok; Lee, Da-Shin; Gill, Tepper; Land, Martin

    2011-12-01

    Although the subject of relativistic dynamics has been explored from both classical and quantum mechanical points of view since the work of Einstein and Dirac, its most striking development has been in the framework of quantum field theory. The very accurate calculations of spectral and scattering properties, for example, of the anamolous magnetic moment of the electron and the Lamb shift in quantum electrodynamics, and many qualitative features of the strong and electroweak interactions, demonstrate the very great power of description achieved in this framework. Yet, many fundamental questions remain to be clarified, such as the structure of classical realtivistic dynamical theories on the level of Hamilton and Lagrange in Minkowski space as well as on the curved manifolds of general relativity. There moreover remains the important question of the covariant classical description of systems at high energy for which particle production effects are not large, such as discussed in Synge's book, The Relativistic Gas, and in Balescu's book on relativistic statistical mechanics. In recent years, the study of high energy plasmas and heavy ion collisions has emphasized the importance of developing the techniques of relativistic mechanics. The results of Linder et al (Phys. Rev. Lett. 95 0040401 (2005)) as well as the more recent work of Palacios et al (Phys. Rev. Lett. 103 253001 (2009)) and others, have shown that there must be a quantum theory with coherence in time. Such a theory, manifestly covariant under the transformations of special relativity with an invariant evolution parameter, such as that of Stueckelberg (Helv. Phys. Acta 14 322, 588 (1941); 15 23 (1942); see also R P Feynman Phys. Rev. 80 4401 and J S Schwinger Phys. Rev. 82 664 (1951)) could provide a suitable basis for the study of such questions, as well as many others for which the application of the standard methods of quantum field theory are difficult to manage, involving, in particular, local

  7. Relativistic quantum nonlocality for the three-qubit Greenberger-Horne-Zeilinger state

    SciTech Connect

    Moradi, Shahpoor

    2008-02-15

    Lorentz transformation of the three-qubit Greenberger-Horne-Zeilinger (GHZ) state is studied. Also we obtain the relativistic spin joint measurement for the transformed state. Using these results it is shown that Bell's inequality is maximally violated for the three-qubit GHZ state in the relativistic regime. For ultrarelativistic particles we obtain the critical value for boost speed, which Bell's inequality is not violated for velocities smaller than this value. We also show that in the ultrarelativistic limit Bell's inequality is maximally violated for the GHZ state.

  8. Adiabatic freezing of long-range quantum correlations in spin chains

    NASA Astrophysics Data System (ADS)

    Shekhar Dhar, Himadri; Rakshit, Debraj; Sen(De, Aditi; Sen, Ujjwal

    2016-06-01

    We consider a process to create quasi-long-range quantum discord between the non-interacting end spins of a quantum spin chain, with the end spins weakly coupled to the bulk of the chain. The process is not only capable of creating long-range quantum correlation but the latter remains frozen, when certain weak end-couplings are adiabatically varied below certain thresholds. We term this phenomenon as adiabatic freezing of quantum correlation. We observe that the freezing is robust to moderate thermal fluctuations and is intrinsically related to the cooperative properties of the quantum spin chain. In particular, we find that the energy gap of the system remains frozen for these adiabatic variations, and moreover, considering the end spins as probes, we show that the interval of freezing can detect the anisotropy transition in quantum XY spin chains. Importantly, the adiabatic freezing of long-range quantum correlations can be simulated with contemporary experimental techniques.

  9. Relativistic Harmonic Oscillators and Hadronic Structures in the Quantum-Mechanics Curriculum

    ERIC Educational Resources Information Center

    Kim, Y. S.; Noz, Marilyn E.

    1978-01-01

    A relativistic harmonic-oscillator formalism which is mathematically simple as the nonrelativistic harmonic oscillator is given. In view of its effectiveness in describing Lorentz-deformed hadrons, the inclusion of this formalism in a first-year graduate course will make the results of high-energy experiments more understandable. (BB)

  10. Relativistic geodesy and gravimetry with quantum sensors - on Earth and in Space

    NASA Astrophysics Data System (ADS)

    Flury, Jakob

    2016-07-01

    Quantum metrology and precision optical metrology enable new measurement techniques on the fields of inertial sensors, extremely precise ranging, atomic frequency standards and optical frequency transfer. Their precision level is highly relevant both for fundamental physics and for geodetic applications, including the monitoring of global and regional change processes in the frame of the Global Geodetic Observing System (GGOS). The Hannover Collaborative Research Center geo-Q focuses on the development of such techniques. We investigate laser interferometry in space - originally developed for gravitational wave astronomy - that can be used for inter-satellite ranging and for optical gravity gradiometry using multiple macroscopic testmasses in order to increase the resolution in satellite gravimetry. Prototypes for these techniques are flown on the LISA pathfinder and GRACE Follow-On missions. Complementarily, sensors based on atom interferometry are promising for accelerometry and gradiometry in terms of sensitivity, versatility and low systematic errors. Optical atomic clocks and optical frequency transfer allow tying gravitational measurements to an atomic reference, which could improve fundamental geodetic reference frames.

  11. Accurate relativistic energy-consistent pseudopotentials for the superheavy elements 111 to 118 including quantum electrodynamic effects

    NASA Astrophysics Data System (ADS)

    Hangele, Tim; Dolg, Michael; Hanrath, Michael; Cao, Xiaoyan; Schwerdtfeger, Peter

    2012-06-01

    Energy-consistent two-component semi-local pseudopotentials for the superheavy elements with atomic numbers 111-118 have been adjusted to fully relativistic multi-configuration Dirac-Hartree-Fock calculations based on the Dirac-Coulomb Hamiltonian, including perturbative corrections for the frequency-dependent Breit interaction in the Coulomb gauge and lowest-order quantum electrodynamic effects. The pseudopotential core includes 92 electrons corresponding to the configuration [Xe]4f 145d105f 14. The parameters for the elements 111-118 were fitted by two-component multi-configuration Hartree-Fock calculations in the intermediate coupling scheme to the total energies of 267 up to 797 J levels arising from 31 up to 62 nonrelativistic configurations, including also anionic and highly ionized states, with mean absolute errors clearly below 0.02 eV for averages corresponding to nonrelativistic configurations. Primitive basis sets for one- and two-component pseudopotential calculations have been optimized for the ground and excited states and exhibit finite basis set errors with respect to the finite-difference Hartree-Fock limit below 0.01 and 0.02 eV, respectively. General contraction schemes have been applied to obtain valence basis sets of polarized valence double- to quadruple-zeta quality. Results of atomic test calculations in the intermediate coupling scheme at the Fock-space coupled-cluster level are in good agreement with those of corresponding fully relativistic all-electron calculations based on the Dirac-Coulomb-Breit Hamiltonian. The results demonstrate besides the well-known need of a relativistic treatment at the Dirac-Coulomb level also the necessity to include higher-order corrections for the superheavy elements.

  12. Accurate relativistic energy-consistent pseudopotentials for the superheavy elements 111 to 118 including quantum electrodynamic effects.

    PubMed

    Hangele, Tim; Dolg, Michael; Hanrath, Michael; Cao, Xiaoyan; Schwerdtfeger, Peter

    2012-06-01

    Energy-consistent two-component semi-local pseudopotentials for the superheavy elements with atomic numbers 111-118 have been adjusted to fully relativistic multi-configuration Dirac-Hartree-Fock calculations based on the Dirac-Coulomb Hamiltonian, including perturbative corrections for the frequency-dependent Breit interaction in the Coulomb gauge and lowest-order quantum electrodynamic effects. The pseudopotential core includes 92 electrons corresponding to the configuration [Xe]4f(14)5d(10)5f(14). The parameters for the elements 111-118 were fitted by two-component multi-configuration Hartree-Fock calculations in the intermediate coupling scheme to the total energies of 267 up to 797 J levels arising from 31 up to 62 nonrelativistic configurations, including also anionic and highly ionized states, with mean absolute errors clearly below 0.02 eV for averages corresponding to nonrelativistic configurations. Primitive basis sets for one- and two-component pseudopotential calculations have been optimized for the ground and excited states and exhibit finite basis set errors with respect to the finite-difference Hartree-Fock limit below 0.01 and 0.02 eV, respectively. General contraction schemes have been applied to obtain valence basis sets of polarized valence double- to quadruple-zeta quality. Results of atomic test calculations in the intermediate coupling scheme at the Fock-space coupled-cluster level are in good agreement with those of corresponding fully relativistic all-electron calculations based on the Dirac-Coulomb-Breit Hamiltonian. The results demonstrate besides the well-known need of a relativistic treatment at the Dirac-Coulomb level also the necessity to include higher-order corrections for the superheavy elements. PMID:22697528

  13. Impact of turbulence in long range quantum and classical communications.

    PubMed

    Capraro, Ivan; Tomaello, Andrea; Dall'Arche, Alberto; Gerlin, Francesca; Ursin, Ruper; Vallone, Giuseppe; Villoresi, Paolo

    2012-11-16

    The study of the free-space distribution of quantum correlations is necessary for any future application of quantum and classical communication aiming to connect two remote locations. Here we study the propagation of a coherent laser beam over 143 km (between Tenerife and La Palma Islands of the Canary archipelagos). By attenuating the beam we also studied the propagation at the single photon level. We investigated the statistic of arrival of the incoming photons and the scintillation of the beam. From the analysis of the data, we propose the exploitation of turbulence to improve the signal to noise ratio of the signal.

  14. Analytic and numerical calculations of quantum synchrotron spectra from relativistic electron distributions

    NASA Technical Reports Server (NTRS)

    Brainerd, J. J.; Petrosian, V.

    1987-01-01

    Calculations are performed numerically and analytically of synchrotron spectra for thermal and power-law electron distributions using the single-particle synchrotron power spectrum derived from quantum electrodynamics. It is found that the photon energy at which quantum effects appear is proportional to temperature and independent of field strength for thermal spectra; quantum effects introduce an exponential roll-off away from the classical spectra. For power law spectra, the photon energy at which quantum effects appear is inversely proportional to the magnetic field strength; quantum effects produce a steeper power law than is found classically. The results are compared with spectra derived from the classical power spectrum with an energy cutoff ensuring conservation of energy. It is found that an energy cutoff is generally an inadequate approximation of quantum effects for low photon energies and for thermal spectra, but gives reasonable results for high-energy emission from power-law electron distributions.

  15. Relativistic self-focusing of ultra-high intensity X-ray laser beams in warm quantum plasma with upward density profile

    SciTech Connect

    Habibi, M.; Ghamari, F.

    2014-05-15

    The results of a numerical study of high-intensity X-ray laser beam interaction with warm quantum plasma (WQP) are presented. By means of an upward ramp density profile combined with quantum factors specially the Fermi velocity, we have demonstrated significant relativistic self-focusing (RSF) of a Gaussian electromagnetic beam in the WQP where the Fermi temperature term in the dielectric function is important. For this purpose, we have considered the quantum hydrodynamics model that modifies refractive index of inhomogeneous WQPs with the inclusion of quantum correction through the quantum statistical and diffraction effects in the relativistic regime. Also, to better illustration of the physical difference between warm and cold quantum plasmas and their effect on the RSF, we have derived the envelope equation governing the spot size of X-ray laser beam in Q-plasmas. In addition to the upward ramp density profile, we have found that the quantum effects would be caused much higher oscillation and better focusing of X-ray laser beam in the WQP compared to that of cold quantum case. Our computational results reveal the importance of the use of electrons density profile and Fermi speed in enhancing self-focusing of laser beam.

  16. Contribution of relativistic quantum chemistry to electron's electric dipole moment for CP violation

    NASA Astrophysics Data System (ADS)

    Abe, M.; Gopakumar, G.; Das, B. P.; Tatewaki, H.; Mukherjee, D.; Hada, M.

    2015-12-01

    The search for the electric dipole moment of the electron (eEDM) is important because it is a probe of Charge Conjugation-Parity (CP) violation. It can also shed light on new physics beyond the standard model. It is not possible to measure the eEDM directly. However, the interaction energy involving the effective electric field (Eeff) acting on an electron in a molecule and the eEDM can be measured. This quantity can be combined with Eeff, which is calculated by relativistic molecular orbital theory to determine eEDM. Previous calculations of Eeff were not sufficiently accurate in the treatment of relativistic or electron correlation effects. We therefore developed a new method to calculate Eeff based on a four-component relativistic coupled-cluster theory. We demonstrated our method for YbF molecule, one of the promising candidates for the eEDM search. Using very large basis set and without freezing any core orbitals, we obtain a value of 23.1 GV/cm for Eeff in YbF with an estimated error of less than 10%. The error is assessed by comparison of our calculations and experiments for two properties relevant for Eeff, permanent dipole moment and hyperfine coupling constant. Our method paves the way to calculate properties of various kinds of molecules which can be described by a single-reference wave function.

  17. Contribution of relativistic quantum chemistry to electron’s electric dipole moment for CP violation

    SciTech Connect

    Abe, M. Gopakumar, G. Hada, M.; Das, B. P.; Tatewaki, H.; Mukherjee, D.

    2015-12-31

    The search for the electric dipole moment of the electron (eEDM) is important because it is a probe of Charge Conjugation-Parity (CP) violation. It can also shed light on new physics beyond the standard model. It is not possible to measure the eEDM directly. However, the interaction energy involving the effective electric field (E{sub eff}) acting on an electron in a molecule and the eEDM can be measured. This quantity can be combined with E{sub eff}, which is calculated by relativistic molecular orbital theory to determine eEDM. Previous calculations of E{sub eff} were not sufficiently accurate in the treatment of relativistic or electron correlation effects. We therefore developed a new method to calculate E{sub eff} based on a four-component relativistic coupled-cluster theory. We demonstrated our method for YbF molecule, one of the promising candidates for the eEDM search. Using very large basis set and without freezing any core orbitals, we obtain a value of 23.1 GV/cm for E{sub eff} in YbF with an estimated error of less than 10%. The error is assessed by comparison of our calculations and experiments for two properties relevant for E{sub eff}, permanent dipole moment and hyperfine coupling constant. Our method paves the way to calculate properties of various kinds of molecules which can be described by a single-reference wave function.

  18. Comment on “Stationary self-focusing of Gaussian laser beam in relativistic thermal quantum plasma” [Phys. Plasmas 20, 072703 (2013)

    SciTech Connect

    Habibi, M.; Ghamari, F.

    2014-06-15

    Patil and Takale in their recent article [Phys. Plasmas 20, 072703 (2013)], by evaluating the quantum dielectric response in thermal quantum plasma, have modeled the relativistic self-focusing of Gaussian laser beam in a plasma. We have found that there are some important shortcomings and fundamental mistakes in Patil and Takale [Phys. Plasmas 20, 072703 (2013)] that we give a brief description about them and refer readers to important misconception about the use of the Fermi temperature in quantum plasmas, appearing in Patil and Takale [Phys. Plasmas 20, 072703 (2013)].

  19. Quantum fluid model of coherent stimulated radiation by a dense relativistic cold electron beam

    SciTech Connect

    Monteiro, L. F.; Serbeto, A.; Tsui, K. H.; Mendonça, J. T.; Galvão, R. M. O.

    2013-07-15

    Using a quantum fluid model, the linear dispersion relation for FEL pumped by a short wavelength laser wiggler is deduced. Subsequently, a new quantum corrected resonance condition is obtained. It is shown that, in the limit of low energy electron beam and low frequency pump, the quantum recoil effect can be neglected, recovering the classical FEL resonance condition, k{sub s}=4k{sub w}γ{sup 2}. On the other hand, for short wavelength and high energy electron beam, the quantum recoil effect becomes strong and the resonance condition turns into k{sub s}=2√(k{sub w}/λ{sub c})γ{sup 3/2}, with λ{sub c} being the reduced Compton wavelength. As a result, a set of nonlinear coupled equations, which describes the quantum FEL dynamics as a three-wave interaction, is obtained. Neglecting wave propagation effects, this set of equations is solved numerically and results are presented.

  20. Phase dependent loading of Bloch bands and quantum simulation of relativistic wave equation predictions with ultracold atoms in variably shaped optical lattice potentials

    NASA Astrophysics Data System (ADS)

    Grossert, Christopher; Leder, Martin; Weitz, Martin

    2016-10-01

    The dispersion relation of ultracold atoms in variably shaped optical lattices can be tuned to resemble that of a relativistic particle, i.e. be linear instead of the usual nonrelativistic quadratic dispersion relation of a free atom. Cold atoms in such a lattice can be used to carry out quantum simulations of relativistic wave equation predictions. We begin this article by describing a Raman technique that allows to selectively load atoms into a desired Bloch band of the lattice near a band crossing. Subsequently, we review two recent experiments with quasirelativistic rubidium atoms in a bichromatic lattice, demonstrating the analogues of Klein tunnelling and Veselago lensing with ultracold atoms, respectively.

  1. a Relativistic Coordinate Space Hartree Finite Nucleus Calculation with AN Interaction that Simulates Short Range Correlation Effects.

    NASA Astrophysics Data System (ADS)

    Luntz, Benjamin Franklin

    Relativistic coordinate space quasiparticle model calculations of finite nuclei are presented in the Hartree approach. The pseudoparticle two-body interaction, developed by the Brooklyn College group to fit relativistic Brueckner -Hartree-Fock reaction matrices for nuclear matter, is transformed from momentum to coordinate space and applied in Hartree calculations of properties of ^{16 }O and ^{40}Ca. The results are similar to recent momentum space Hartree-Fock results from the Brooklyn College group using the same pseudoparticle interaction.

  2. Relativistic diffusion

    NASA Astrophysics Data System (ADS)

    Haba, Z.

    2009-02-01

    We discuss relativistic diffusion in proper time in the approach of Schay (Ph.D. thesis, Princeton University, Princeton, NJ, 1961) and Dudley [Ark. Mat. 6, 241 (1965)]. We derive (Langevin) stochastic differential equations in various coordinates. We show that in some coordinates the stochastic differential equations become linear. We obtain momentum probability distribution in an explicit form. We discuss a relativistic particle diffusing in an external electromagnetic field. We solve the Langevin equations in the case of parallel electric and magnetic fields. We derive a kinetic equation for the evolution of the probability distribution. We discuss drag terms leading to an equilibrium distribution. The relativistic analog of the Ornstein-Uhlenbeck process is not unique. We show that if the drag comes from a diffusion approximation to the master equation then its form is strongly restricted. The drag leading to the Tsallis equilibrium distribution satisfies this restriction whereas the one of the Jüttner distribution does not. We show that any function of the relativistic energy can be the equilibrium distribution for a particle in a static electric field. A preliminary study of the time evolution with friction is presented. It is shown that the problem is equivalent to quantum mechanics of a particle moving on a hyperboloid with a potential determined by the drag. A relation to diffusions appearing in heavy ion collisions is briefly discussed.

  3. Relativistic diffusion.

    PubMed

    Haba, Z

    2009-02-01

    We discuss relativistic diffusion in proper time in the approach of Schay (Ph.D. thesis, Princeton University, Princeton, NJ, 1961) and Dudley [Ark. Mat. 6, 241 (1965)]. We derive (Langevin) stochastic differential equations in various coordinates. We show that in some coordinates the stochastic differential equations become linear. We obtain momentum probability distribution in an explicit form. We discuss a relativistic particle diffusing in an external electromagnetic field. We solve the Langevin equations in the case of parallel electric and magnetic fields. We derive a kinetic equation for the evolution of the probability distribution. We discuss drag terms leading to an equilibrium distribution. The relativistic analog of the Ornstein-Uhlenbeck process is not unique. We show that if the drag comes from a diffusion approximation to the master equation then its form is strongly restricted. The drag leading to the Tsallis equilibrium distribution satisfies this restriction whereas the one of the Jüttner distribution does not. We show that any function of the relativistic energy can be the equilibrium distribution for a particle in a static electric field. A preliminary study of the time evolution with friction is presented. It is shown that the problem is equivalent to quantum mechanics of a particle moving on a hyperboloid with a potential determined by the drag. A relation to diffusions appearing in heavy ion collisions is briefly discussed.

  4. Critical behavior of quantum magnets with long-range interactions in the thermodynamic limit

    NASA Astrophysics Data System (ADS)

    Fey, Sebastian; Schmidt, Kai Phillip

    2016-08-01

    Quasiparticle properties of quantum magnets with long-range interactions are investigated by high-order linked-cluster expansions in the thermodynamic limit. It is established that perturbative continuous unitary transformations on white graphs are a promising and flexible approach to treat long-range interactions in quantum many-body systems. We exemplify this scheme for the one-dimensional transverse-field Ising chain with long-range interactions. For this model, the elementary quasiparticle gap is determined allowing to access the quantum-critical regime including critical exponents and multiplicative logarithmic corrections for the ferro- and antiferromagnetic case.

  5. Relativistic geodesy

    NASA Astrophysics Data System (ADS)

    Flury, J.

    2016-06-01

    Quantum metrology enables new applications in geodesy, including relativistic geodesy. The recent progress in optical atomic clocks and in long-distance frequency transfer by optical fiber together pave the way for using measurements of the gravitational frequency redshift for geodesy. The remote comparison of frequencies generated by calibrated clocks will allow for a purely relativistic determination of differences in gravitational potential and height between stations on Earth surface (chronometric leveling). The long-term perspective is to tie potential and height differences to atomic standards in order to overcome the weaknesses and inhomogeneity of height systems determined by classical spirit leveling. Complementarily, gravity measurements with atom interferometric setups, and satellite gravimetry with space borne laser interferometers allow for new sensitivities in the measurement of the Earth's gravity field.

  6. Microscopic nonlinear relativistic quantum theory of absorption of powerful x-ray radiation in plasma.

    PubMed

    Avetissian, H K; Ghazaryan, A G; Matevosyan, H H; Mkrtchian, G F

    2015-10-01

    The microscopic quantum theory of plasma nonlinear interaction with the coherent shortwave electromagnetic radiation of arbitrary intensity is developed. The Liouville-von Neumann equation for the density matrix is solved analytically considering a wave field exactly and a scattering potential of plasma ions as a perturbation. With the help of this solution we calculate the nonlinear inverse-bremsstrahlung absorption rate for a grand canonical ensemble of electrons. The latter is studied in Maxwellian, as well as in degenerate quantum plasma for x-ray lasers at superhigh intensities and it is shown that one can achieve the efficient absorption coefficient in these cases.

  7. Quantum correlation dynamics subjected to critical spin environment with short-range anisotropic interaction

    NASA Astrophysics Data System (ADS)

    Guo, J. L.; Zhang, X. Z.

    2016-09-01

    Short-range interaction among the spins can not only results in the rich phase diagram but also brings about fascinating phenomenon both in the contexts of quantum computing and information. In this paper, we investigate the quantum correlation of the system coupled to a surrounding environment with short-range anisotropic interaction. It is shown that the decay of quantum correlation of the central spins measured by pairwise entanglement and quantum discord can serve as a signature of quantum phase transition. In addition, we study the decoherence factor of the system when the environment is in the vicinity of the phase transition point. In the strong coupling regime, the decay of the decoherence factor exhibits Gaussian envelop in the time domain. However, in weak coupling limit, the quantum correlation of the system is robust against the disturbance of the magnetic field through optimal control of the anisotropic short-range interaction strength. Based on this, the effects of the short-range anisotropic interaction on the sudden transition from classical to quantum decoherence are also presented.

  8. Quantum correlation dynamics subjected to critical spin environment with short-range anisotropic interaction.

    PubMed

    Guo, J L; Zhang, X Z

    2016-01-01

    Short-range interaction among the spins can not only results in the rich phase diagram but also brings about fascinating phenomenon both in the contexts of quantum computing and information. In this paper, we investigate the quantum correlation of the system coupled to a surrounding environment with short-range anisotropic interaction. It is shown that the decay of quantum correlation of the central spins measured by pairwise entanglement and quantum discord can serve as a signature of quantum phase transition. In addition, we study the decoherence factor of the system when the environment is in the vicinity of the phase transition point. In the strong coupling regime, the decay of the decoherence factor exhibits Gaussian envelop in the time domain. However, in weak coupling limit, the quantum correlation of the system is robust against the disturbance of the magnetic field through optimal control of the anisotropic short-range interaction strength. Based on this, the effects of the short-range anisotropic interaction on the sudden transition from classical to quantum decoherence are also presented. PMID:27596050

  9. Quantum correlation dynamics subjected to critical spin environment with short-range anisotropic interaction

    PubMed Central

    Guo, J. L.; Zhang, X. Z.

    2016-01-01

    Short-range interaction among the spins can not only results in the rich phase diagram but also brings about fascinating phenomenon both in the contexts of quantum computing and information. In this paper, we investigate the quantum correlation of the system coupled to a surrounding environment with short-range anisotropic interaction. It is shown that the decay of quantum correlation of the central spins measured by pairwise entanglement and quantum discord can serve as a signature of quantum phase transition. In addition, we study the decoherence factor of the system when the environment is in the vicinity of the phase transition point. In the strong coupling regime, the decay of the decoherence factor exhibits Gaussian envelop in the time domain. However, in weak coupling limit, the quantum correlation of the system is robust against the disturbance of the magnetic field through optimal control of the anisotropic short-range interaction strength. Based on this, the effects of the short-range anisotropic interaction on the sudden transition from classical to quantum decoherence are also presented. PMID:27596050

  10. Quantum theory of stimulated Cherenkov emission and stimulated compton scattering of electromagnetic waves by a low-density relativistic electron beam

    SciTech Connect

    Kuzelev, M. V.

    2010-07-15

    A quantum theory of instabilities of a relativistic electron beam due to the stimulated Cherenkov effect in a dielectric and the stimulated Compton effect in vacuum is presented. The instability growth rates are found in a linear approximation and are shown to go over to the familiar growth rates in the classical approximation. A nonlinear theory of instabilities in the quantum case is developed. Analytic solutions are obtained that describe the nonlinear saturation of the amplitudes of the electromagnetic waves emitted by the beam.

  11. Effect of relativistic acceleration on localized two-mode Gaussian quantum states

    NASA Astrophysics Data System (ADS)

    Ahmadi, Mehdi; Lorek, Krzysztof; Checińska, Agata; Smith, Alexander R. H.; Mann, Robert B.; Dragan, Andrzej

    2016-06-01

    We study how an arbitrary Gaussian state of two localized wave packets, prepared in an inertial frame of reference, is described by a pair of uniformly accelerated observers. We explicitly compute the resulting state for arbitrarily chosen proper accelerations of the observers and independently tuned distance between them. To do so, we introduce a generalized Rindler frame of reference and analytically derive the corresponding state transformation as a Gaussian channel. Our approach provides several new insights into the phenomenon of vacuum entanglement such as the highly nontrivial effect of spatial separation between the observers including sudden death of entanglement. We also calculate the fidelity of the two-mode channel for nonvacuum Gaussian states and obtain bounds on classical and quantum capacities of a single-mode channel. Our framework can be directly applied to any continuous variable quantum information protocol in which the effects of acceleration or gravity cannot be neglected.

  12. PREFACE: The 9th Biennial Conference on Classical and Quantum Relativistic Dynamics of Particles and Fields

    NASA Astrophysics Data System (ADS)

    Horwitz, L. P.

    2015-05-01

    The most recent meeting took place at the University of Connecticut, Storrs, on June 9-13, 2014. This meeting forms the basis for the Proceedings that are recorded in this issue of the Journal of Physics: Conference Series. Along with the work of some of the founding members of the Association, we were fortunate to have lecturers from application areas that provided strong challenges for further developments in quantum field theory, cosmological problems, and in the dynamics of systems subject to accelerations and the effects of general relativity. Topics treated in this issue include studies of the dark matter problem, rotation curves, and, in particular, for the (relatively accessible) Milky Way galaxy, compact stellar objects, a composite particle model, and the properties of a conformally invariant theory with spontaneous symmetry breaking. The Stueckelberg theory is further investigated for its properties in producing bremsstrahlung and pair production and apparent superluminal effects, and, as mentioned above, the implications of low energy nuclear reactions for such off-shell theories. Other "proper time" theories are investigated as well, and a study of the clock synchronization problem is presented. A mathematical study of to quantum groupo associated with the Toda lattice and its implications for quantum field theory, as well as a phenomenological discussion of supernova mechanics as well as a semiclassical discussion of electron spin and the question of the compatibility of special relativity and the quantum theory. A careful analysis of the covariant Aharonov-Bohm effect is given as well. The quantization of massless fields and the relation to the Maxwell theory is also discussed. We wish to thank the participants who contributed very much through their lectures, personal discussions, and these papers, to the advancement of the subject and our understanding.

  13. Restricted numerical range: A versatile tool in the theory of quantum information

    NASA Astrophysics Data System (ADS)

    Gawron, Piotr; Puchała, Zbigniew; Miszczak, Jarosław Adam; Skowronek, Łukasz; Życzkowski, Karol

    2010-10-01

    Numerical range of a Hermitian operator X is defined as the set of all possible expectation values of this observable among a normalized quantum state. We analyze a modification of this definition in which the expectation value is taken among a certain subset of the set of all quantum states. One considers, for instance, the set of real states, the set of product states, separable states, or the set of maximally entangled states. We show exemplary applications of these algebraic tools in the theory of quantum information: analysis of k-positive maps and entanglement witnesses, as well as study of the minimal output entropy of a quantum channel. Product numerical range of a unitary operator is used to solve the problem of local distinguishability of a family of two unitary gates.

  14. Relativistic geodesy and gravimetry with quantum sensors: current developments and geodetic perspectives

    NASA Astrophysics Data System (ADS)

    Flury, Jakob; Müller, Jürgen

    2016-04-01

    The recent breakthroughs in long-distance frequency comparisons of Strontium optical atomic clocks through phase-stabilized optical fibers open a new field for geodesy. The results obtained are already consistent with the expected gravitational frequency redshift between the involved stations at a level that corresponds to an inaccuracy of less than 1 m in height difference, and an improvement towards the cm accuracy level is expected rather soon. Particularly interesting is the fundamentally new perspective of tying potential differences and height differences to an atomic reference. Potential applications include regional geoid determination and the connection of height systems and tide gauges. In a broader view, quantum metrology offers many options for gravity related measurements. For optical clocks, relevant levels of precision and accuracy are obtained from a rather large variety of atomic species, both for clocks interrogating many neutral atoms in optical lattices, and for single-ion clocks using quantum logic that enables accessing particularly favorable atomic transitions. To assess the advantages of the different options and to choose specific setups is a challenge both for the re-definition of the SI second and for geodetic applications. Similarly, and closely related, atom interferometry offers many options for gravity related measurements. Different species in a variety of setups are being used successfully to determine gravity accelerations and its spatial derivatives.

  15. On the range of the generator of a quantum Markov semigroup

    NASA Astrophysics Data System (ADS)

    Bolaños-Servin, Jorge R.; Fagnola, Franco

    2015-12-01

    We show that the commutant of the range of the infinitesimal generator of a norm-continuous quantum Markov semigroup on ℬ(h), not consisting of identity maps, with a faithful normal invariant state is trivial whenever the fixed point algebra is atomic. As a consequence, two formulations of the irreversible (H,β)-KMS condition proposed in Ref. 2 are equivalent for this class of quantum Markov semigroups.

  16. Effects of adiabatic, relativistic, and quantum electrodynamics interactions on the pair potential and thermophysical properties of helium.

    PubMed

    Cencek, Wojciech; Przybytek, Michał; Komasa, Jacek; Mehl, James B; Jeziorski, Bogumił; Szalewicz, Krzysztof

    2012-06-14

    The adiabatic, relativistic, and quantum electrodynamics (QED) contributions to the pair potential of helium were computed, fitted separately, and applied, together with the nonrelativistic Born-Oppenheimer (BO) potential, in calculations of thermophysical properties of helium and of the properties of the helium dimer. An analysis of the convergence patterns of the calculations with increasing basis set sizes allowed us to estimate the uncertainties of the total interaction energy to be below 50 ppm for interatomic separations R smaller than 4 bohrs and for the distance R = 5.6 bohrs. For other separations, the relative uncertainties are up to an order of magnitude larger (and obviously still larger near R = 4.8 bohrs where the potential crosses zero) and are dominated by the uncertainties of the nonrelativistic BO component. These estimates also include the contributions from the neglected relativistic and QED terms proportional to the fourth and higher powers of the fine-structure constant α. To obtain such high accuracy, it was necessary to employ explicitly correlated Gaussian expansions containing up to 2400 terms for smaller R (all R in the case of a QED component) and optimized orbital bases up to the cardinal number X = 7 for larger R. Near-exact asymptotic constants were used to describe the large-R behavior of all components. The fitted potential, exhibiting the minimum of -10.996 ± 0.004 K at R = 5.608 0 ± 0.000 1 bohr, was used to determine properties of the very weakly bound (4)He(2) dimer and thermophysical properties of gaseous helium. It is shown that the Casimir-Polder retardation effect, increasing the dimer size by about 2 Å relative to the nonrelativistic BO value, is almost completely accounted for by the inclusion of the Breit-interaction and the Araki-Sucher contributions to the potential, of the order α(2) and α(3), respectively. The remaining retardation effect, of the order of α(4) and higher, is practically negligible for the bound

  17. Quantum phases from competing short- and long-range interactions in an optical lattice

    NASA Astrophysics Data System (ADS)

    Landig, Renate; Hruby, Lorenz; Dogra, Nishant; Landini, Manuele; Mottl, Rafael; Donner, Tobias; Esslinger, Tilman

    2016-04-01

    Insights into complex phenomena in quantum matter can be gained from simulation experiments with ultracold atoms, especially in cases where theoretical characterization is challenging. However, these experiments are mostly limited to short-range collisional interactions; recently observed perturbative effects of long-range interactions were too weak to reach new quantum phases. Here we experimentally realize a bosonic lattice model with competing short- and long-range interactions, and observe the appearance of four distinct quantum phases—a superfluid, a supersolid, a Mott insulator and a charge density wave. Our system is based on an atomic quantum gas trapped in an optical lattice inside a high-finesse optical cavity. The strength of the short-range on-site interactions is controlled by means of the optical lattice depth. The long (infinite)-range interaction potential is mediated by a vacuum mode of the cavity and is independently controlled by tuning the cavity resonance. When probing the phase transition between the Mott insulator and the charge density wave in real time, we observed a behaviour characteristic of a first-order phase transition. Our measurements have accessed a regime for quantum simulation of many-body systems where the physics is determined by the intricate competition between two different types of interactions and the zero point motion of the particles.

  18. Quantum phases from competing short- and long-range interactions in an optical lattice.

    PubMed

    Landig, Renate; Hruby, Lorenz; Dogra, Nishant; Landini, Manuele; Mottl, Rafael; Donner, Tobias; Esslinger, Tilman

    2016-04-28

    Insights into complex phenomena in quantum matter can be gained from simulation experiments with ultracold atoms, especially in cases where theoretical characterization is challenging. However, these experiments are mostly limited to short-range collisional interactions; recently observed perturbative effects of long-range interactions were too weak to reach new quantum phases. Here we experimentally realize a bosonic lattice model with competing short- and long-range interactions, and observe the appearance of four distinct quantum phases--a superfluid, a supersolid, a Mott insulator and a charge density wave. Our system is based on an atomic quantum gas trapped in an optical lattice inside a high-finesse optical cavity. The strength of the short-range on-site interactions is controlled by means of the optical lattice depth. The long (infinite)-range interaction potential is mediated by a vacuum mode of the cavity and is independently controlled by tuning the cavity resonance. When probing the phase transition between the Mott insulator and the charge density wave in real time, we observed a behaviour characteristic of a first-order phase transition. Our measurements have accessed a regime for quantum simulation of many-body systems where the physics is determined by the intricate competition between two different types of interactions and the zero point motion of the particles. PMID:27064902

  19. Radiation from relativistic electrons in "light" and in conventional undulators. Classical and quantum approaches

    NASA Astrophysics Data System (ADS)

    Potylitsyn, A. P.; Kolchuzhkin, A. M.; Strokov, S. A.

    2016-07-01

    A photon spectrum of undulator radiation (UR) is calculated in the semi-classical approach. The UR intensity spectrum is determined by an electron trajectory in the undulator neglecting by energy losses for radiation. Using the Planck's law, the UR photon spectrum can be calculated from the classical intensity spectrum both for linear and nonlinear regimes. The radiation of an electron in a field of strong electromagnetic wave (radiation in the "light" undulator) is considered in the quantum electromagnetic frame. Comparison of results obtained by both approaches has been shown that UR spectra in the whole cone coincide with high accuracy for the case x<<1. Characteristics of the collimated UR beam were simulated with taking into account the discrete process of photon emission along an electron trajectory in both kinds of undulators.

  20. Weakly relativistic plasma expansion

    SciTech Connect

    Fermous, Rachid Djebli, Mourad

    2015-04-15

    Plasma expansion is an important physical process that takes place in laser interactions with solid targets. Within a self-similar model for the hydrodynamical multi-fluid equations, we investigated the expansion of both dense and under-dense plasmas. The weakly relativistic electrons are produced by ultra-intense laser pulses, while ions are supposed to be in a non-relativistic regime. Numerical investigations have shown that relativistic effects are important for under-dense plasma and are characterized by a finite ion front velocity. Dense plasma expansion is found to be governed mainly by quantum contributions in the fluid equations that originate from the degenerate pressure in addition to the nonlinear contributions from exchange and correlation potentials. The quantum degeneracy parameter profile provides clues to set the limit between under-dense and dense relativistic plasma expansions at a given density and temperature.

  1. Pricing of range accrual swap in the quantum finance Libor Market Model

    NASA Astrophysics Data System (ADS)

    Baaquie, Belal E.; Du, Xin; Tang, Pan; Cao, Yang

    2014-05-01

    We study the range accrual swap in the quantum finance formulation of the Libor Market Model (LMM). It is shown that the formulation can exactly price the path dependent instrument. An approximate price is obtained as an expansion in the volatility of Libor. The Monte Carlo simulation method is used to study the nonlinear domain of the model and determine the range of validity of the approximate formula. The price of accrual swap is analyzed by generating daily sample values by simulating a two dimension Gaussian quantum field.

  2. Quantum gases. Observation of many-body dynamics in long-range tunneling after a quantum quench.

    PubMed

    Meinert, Florian; Mark, Manfred J; Kirilov, Emil; Lauber, Katharina; Weinmann, Philipp; Gröbner, Michael; Daley, Andrew J; Nägerl, Hanns-Christoph

    2014-06-13

    Quantum tunneling is at the heart of many low-temperature phenomena. In strongly correlated lattice systems, tunneling is responsible for inducing effective interactions, and long-range tunneling substantially alters many-body properties in and out of equilibrium. We observe resonantly enhanced long-range quantum tunneling in one-dimensional Mott-insulating Hubbard chains that are suddenly quenched into a tilted configuration. Higher-order tunneling processes over up to five lattice sites are observed as resonances in the number of doubly occupied sites when the tilt per site is tuned to integer fractions of the Mott gap. This forms a basis for a controlled study of many-body dynamics driven by higher-order tunneling and demonstrates that when some degrees of freedom are frozen out, phenomena that are driven by small-amplitude tunneling terms can still be observed. PMID:24926015

  3. Coupled quantum-classical method for long range charge transfer: relevance of the nuclear motion to the quantum electron dynamics

    NASA Astrophysics Data System (ADS)

    da Silva, Robson; Hoff, Diego A.; Rego, Luis G. C.

    2015-04-01

    Charge and excitonic-energy transfer phenomena are fundamental for energy conversion in solar cells as well as artificial photosynthesis. Currently, much interest is being paid to light-harvesting and energy transduction processes in supramolecular structures, where nuclear dynamics has a major influence on electronic quantum dynamics. For this reason, the simulation of long range electron transfer in supramolecular structures, under environmental conditions described within an atomistic framework, has been a difficult problem to study. This work describes a coupled quantum mechanics/molecular mechanics method that aims at describing long range charge transfer processes in supramolecular systems, taking into account the atomistic details of large molecular structures, the underlying nuclear motion, and environmental effects. The method is applied to investigate the relevance of electron-nuclei interaction on the mechanisms for photo-induced electron-hole pair separation in dye-sensitized interfaces as well as electronic dynamics in molecular structures.

  4. Note: Increasing dynamic range of digital-to-analog converter using a superconducting quantum interference device.

    PubMed

    Nakanishi, Masakazu

    2014-10-01

    Responses of a superconducting quantum interference device (SQUID) are periodically dependent on magnetic flux coupling to its superconducting ring and the period is a flux quantum (Φo = h/2e, where h and e, respectively, express Planck's constant and elementary charge). Using this periodicity, we had proposed a digital to analog converter using a SQUID (SQUID DAC) of first generation with linear current output, interval of which corresponded to Φo. Modification for increasing dynamic range by interpolating within each interval is reported. Linearity of the interpolation was also based on the quantum periodicity. A SQUID DAC with dynamic range of about 1.4 × 10(7) was created as a demonstration.

  5. Note: Increasing dynamic range of digital-to-analog converter using a superconducting quantum interference device

    SciTech Connect

    Nakanishi, Masakazu

    2014-10-15

    Responses of a superconducting quantum interference device (SQUID) are periodically dependent on magnetic flux coupling to its superconducting ring and the period is a flux quantum (Φ{sub o} = h/2e, where h and e, respectively, express Planck's constant and elementary charge). Using this periodicity, we had proposed a digital to analog converter using a SQUID (SQUID DAC) of first generation with linear current output, interval of which corresponded to Φ{sub o}. Modification for increasing dynamic range by interpolating within each interval is reported. Linearity of the interpolation was also based on the quantum periodicity. A SQUID DAC with dynamic range of about 1.4 × 10{sup 7} was created as a demonstration.

  6. Relativistic mirrors in laser plasmas (analytical methods)

    NASA Astrophysics Data System (ADS)

    Bulanov, S. V.; Esirkepov, T. Zh; Kando, M.; Koga, J.

    2016-10-01

    Relativistic flying mirrors in plasmas are realized as thin dense electron (or electron-ion) layers accelerated by high-intensity electromagnetic waves to velocities close to the speed of light in vacuum. The reflection of an electromagnetic wave from the relativistic mirror results in its energy and frequency changing. In a counter-propagation configuration, the frequency of the reflected wave is multiplied by the factor proportional to the Lorentz factor squared. This scientific area promises the development of sources of ultrashort x-ray pulses in the attosecond range. The expected intensity will reach the level at which the effects predicted by nonlinear quantum electrodynamics start to play a key role. We present an overview of theoretical methods used to describe relativistic flying, accelerating, oscillating mirrors emerging in intense laser-plasma interactions.

  7. Perspective: relativistic effects.

    PubMed

    Autschbach, Jochen

    2012-04-21

    This perspective article discusses some broadly-known and some less broadly-known consequences of Einstein's special relativity in quantum chemistry, and provides a brief outline of the theoretical methods currently in use, along with a discussion of recent developments and selected applications. The treatment of the electron correlation problem in relativistic quantum chemistry methods, and expanding the reach of the available relativistic methods to calculate all kinds of energy derivative properties, in particular spectroscopic and magnetic properties, requires on-going efforts. PMID:22519307

  8. Perspective: relativistic effects.

    PubMed

    Autschbach, Jochen

    2012-04-21

    This perspective article discusses some broadly-known and some less broadly-known consequences of Einstein's special relativity in quantum chemistry, and provides a brief outline of the theoretical methods currently in use, along with a discussion of recent developments and selected applications. The treatment of the electron correlation problem in relativistic quantum chemistry methods, and expanding the reach of the available relativistic methods to calculate all kinds of energy derivative properties, in particular spectroscopic and magnetic properties, requires on-going efforts.

  9. Adiabatic two-photon quantum gate operations using a long-range photonic bus

    NASA Astrophysics Data System (ADS)

    Hope, Anthony P.; Nguyen, Thach G.; Mitchell, Arnan; Greentree, Andrew D.

    2015-03-01

    Adiabatic techniques have much potential to realize practical and robust optical waveguide devices. Traditionally, photonic elements are limited to coupling schemes that rely on proximity to nearest neighbour elements. We combine adiabatic passage with a continuum based long-range optical bus to break free from such topological restraints and thereby outline a new approach to photonic quantum gate design. We explicitly show designs for adiabatic quantum gates that produce a Hadamard, 50:50 and 1/3:2/3 beam splitter, and non-deterministic controlled NOT gate based on planar thin, shallow ridge waveguides. Our calculations are performed under conditions of one and two-photon inputs.

  10. A Simple Relativistic Bohr Atom

    ERIC Educational Resources Information Center

    Terzis, Andreas F.

    2008-01-01

    A simple concise relativistic modification of the standard Bohr model for hydrogen-like atoms with circular orbits is presented. As the derivation requires basic knowledge of classical and relativistic mechanics, it can be taught in standard courses in modern physics and introductory quantum mechanics. In addition, it can be shown in a class that…

  11. Long-range string orders and topological quantum phase transitions in the one-dimensional quantum compass model.

    PubMed

    Wang, Hai Tao; Cho, Sam Young

    2015-01-14

    In order to investigate the quantum phase transition in the one-dimensional quantum compass model, we numerically calculate non-local string correlations, entanglement entropy and fidelity per lattice site by using the infinite matrix product state representation with the infinite time evolving block decimation method. In the whole range of the interaction parameters, we find that four distinct string orders characterize the four different Haldane phases and the topological quantum phase transition occurs between the Haldane phases. The critical exponents of the string order parameters β = 1/8 and the cental charges c = 1/2 at the critical points show that the topological phase transitions between the phases belong to an Ising type of universality classes. In addition to the string order parameters, the singularities of the second derivative of the ground state energies per site, the continuous and singular behaviors of the Von Neumann entropy and the pinch points of the fidelity per lattice site manifest that the phase transitions between the phases are of the second-order, in contrast to the first-order transition suggested in previous studies.

  12. Long range emission enhancement and anisotropy in coupled quantum dots induced by aligned gold nanoantenna

    SciTech Connect

    Tripathi, L. N.; Praveena, M.; Valson, Pranay; Basu, J. K.

    2014-10-20

    Quantum dot arrays have been projected as the material of choice for next generation displays and photodetectors. Extensive ongoing research aims at improving optical and electrical efficiencies of such devices. We report experimental results on non-local long range emission intensity enhancement and anisotropy in quantum dot assemblies induced by isolated and partially aligned gold nanoantennas. Spatially resolved photoluminescence clearly demonstrate that the effect is maximum, when the longitudinal surface plasmon resonance of the nanoantenna is resonant with the emission maxima of the quantum dots. We estimated the decay length of this enhancement to be ∼2.6 μm, which is considerably larger than the range of near field interaction of metal nanoantenna. Numerical simulations qualitatively capture the near field behavior of the nanorods but fail to match the experimentally observed non-local effects. We have suggested how strong interactions of quantum dots in the close packed assemblies, mediated by the nanoantennas, could lead to such observed behavior.

  13. Relativistic Fermions in a Magnetic Field: From Quantum Hall Effect in Graphene to Chiral Asymmetry in QED

    NASA Astrophysics Data System (ADS)

    Xia, Lifang

    In the first part of this thesis, we use the generalized Landau-level represen- tation to study the effect of screening on the properties of the graphene quantum Hall states with integer filling factors. The analysis is performed in the low-energy Dirac model in the mean-field approximation, in which the long-range Coulomb in- teraction is modified by the one-loop static screening effects. The solutions demon- strate that static screening leads to a substantial suppression of the gap parameters in the quantum Hall states with a broken U (4) flavor symmetry. The results of the temperature dependence of the energy gaps mimic well the temperature dependence of the activation energies measured in experiment. The Landau-level running of the quasiparticle dynamical parameters could be tested via optical studies of the integer quantum Hall states. In the second part, by using the generalized Landau-level representation, we study the interaction induced chiral asymmetry in cold QED plasma beyond the weak-field approximation. The chiral shift and the parity-even chiral chemical potential function are obtained numerically and are found peaking near the Fermi surface and increases and decreases with the Landau level index, respectively. The results are used to quantify the chiral asymmetry of the Fermi surface in dense QED matter. The chiral asymmetry appears to be rather small even in the strongest mag- netic fields and at the highest stellar densities. However, the analogous asymmetry can be substantial in the case of dense quark matter.

  14. Divergence of the entanglement range in low-dimensional quantum systems

    SciTech Connect

    Amico, L.; Patane, D.; Baroni, F.; Fubini, A.; Tognetti, V.; Verrucchi, Paola

    2006-08-15

    We study the pairwise entanglement close to separable ground states of a class of one-dimensional quantum spin models. At T=0 we find that such ground states separate regions, in the space of the Hamiltonian parameters, which are characterized by qualitatively different types of entanglement, namely parallel and antiparallel entanglement; we further demonstrate that the range of the concurrence diverges while approaching separable ground states, therefore evidencing that such states, with uncorrelated fluctuations, are reached by a long range reshuffling of the entanglement. We generalize our results to the analysis of quantum phase transitions occurring in bosonic and fermionic systems. Finally, the effects of finite temperature are considered: At T>0 we evidence the existence of a region where no pairwise entanglement survives, so that entanglement, if present, is genuinely multipartite.

  15. Effects of long-range hopping and interactions on quantum walks in ordered and disordered lattices

    NASA Astrophysics Data System (ADS)

    Chattaraj, T.; Krems, R. V.

    2016-08-01

    We study the effects of long-range hopping and long-range interparticle interactions on the quantum walk of hard-core bosons in ideal and disordered one-dimensional lattices. We find that the range of hopping has a much more significant effect on the particle correlation dynamics than the range of interactions. We illustrate that long-range hopping makes the correlation diagrams asymmetric with respect to the sign of the interaction. We examine the relative role of repulsive and attractive interactions on the dynamics of scattering by isolated impurities and Anderson localization in disordered lattices. We show that weakly repulsive interactions increase the probability of tunneling through isolated impurities and decrease the localization.

  16. Relativistic Quantum Chemistry of Heavy Elements: Interatomic potentials and Lines Shift for Systems 'Alkali Elements-Inert Gases'

    SciTech Connect

    Glushkov, A. V.; Khetselius, O.; Gurnitskaya, E.; Loboda, A.; Mischenko, E.

    2009-03-09

    New relativistic approach, based on the gauge-invariant perturbation theory (PT) with using the optimized wave functions basis's, is applied to calculating the inter atomic potentials, hyper fine structure (hfs) collision shift for alkali atoms in atmosphere of inert gases. Data for inter atomic potentials, collision shifts of the Rb and Cs atoms in atmosphere of the inert gas He are presented.

  17. Quantum spin dynamics and entanglement in systems with long-range interactions

    NASA Astrophysics Data System (ADS)

    Rey, Ana M.

    One of the fundamental goals of modern quantum sciences is to learn how to control and manipulate non-equilibrium many-body systems and use them to make powerful and improved quantum devices, materials and technologies. However, out-of-equilibrium systems are complex, typically strongly correlated and entangled, and thus to model them we are in an urgent need of new methodologies. In this talk I will discuss new theoretical methods that we have developed to investigate emergent non-equilibrium phenomena in driven-dissipative spin systems interacting via long-range interactions. I will show we can capture the dynamics of correlations and entanglement in close systems and the interplay between dissipation and entanglement in open quantum systems including spin-boson models. As a specific application I will discuss the use of our methods to model the spin dynamics exhibited by arrays of trapped ions with controllable long-range interactions. I will show that our predictions are consistent with recent experimental measurements. I will also discuss new protocols to diagnostic and characterize entanglement based on well-established NMR protocols This work is supported by NSF, ARO, AFOSR-MURI, and NIST.

  18. Exploring negative refraction conditions for quantum cascade semiconductor metamaterials in the terahertz spectral range

    NASA Astrophysics Data System (ADS)

    Daničić, A.; Radovanović, J.; Ramović, S.; Milanović, V.

    2016-03-01

    In order to avoid losses in metamaterial unit cells at frequencies of interest, caused by metallic inclusions, an active medium design has been proposed. As candidate structures for this active medium, we have chosen quantum cascade lasers because of their high output gain. Here we analyze and compare two quantum cascade structures that emit at 4.6 THz and 3.9 THz, respectively, placed under the influence of a strong magnetic field. We first solve the full system of rate equations for all relevant Landau levels, and obtain the necessary information about carrier distribution among the levels, after which we are able to evaluate the permittivity component along the growth direction of the structure. With these data one can determine the conditions under which negative refraction occurs, and calculate the values of the refractive index of the structure, as well as the range of frequencies at which the structure exhibits negative refraction for a predefined total electron sheet density.

  19. Quantum transport with long-range steps on Watts-Strogatz networks

    NASA Astrophysics Data System (ADS)

    Wang, Yan; Xu, Xin-Jian

    2016-07-01

    We study transport dynamics of quantum systems with long-range steps on the Watts-Strogatz network (WSN) which is generated by rewiring links of the regular ring. First, we probe physical systems modeled by the discrete nonlinear schrödinger (DNLS) equation. Using the localized initial condition, we compute the time-averaged occupation probability of the initial site, which is related to the nonlinearity, the long-range steps and rewiring links. Self-trapping transitions occur at large (small) nonlinear parameters for coupling ɛ=-1 (1), as long-range interactions are intensified. The structure disorder induced by random rewiring, however, has dual effects for ɛ=-1 and inhibits the self-trapping behavior for ɛ=1. Second, we investigate continuous-time quantum walks (CTQW) on the regular ring ruled by the discrete linear schrödinger (DLS) equation. It is found that only the presence of the long-range steps does not affect the efficiency of the coherent exciton transport, while only the allowance of random rewiring enhances the partial localization. If both factors are considered simultaneously, localization is greatly strengthened, and the transport becomes worse.

  20. Coherent quantum states of a relativistic particle in an electromagnetic plane wave and a parallel magnetic field

    SciTech Connect

    Colavita, E.; Hacyan, S.

    2014-03-15

    We analyze the solutions of the Klein–Gordon and Dirac equations describing a charged particle in an electromagnetic plane wave combined with a magnetic field parallel to the direction of propagation of the wave. It is shown that the Klein–Gordon equation admits coherent states as solutions, while the corresponding solutions of the Dirac equation are superpositions of coherent and displaced-number states. Particular attention is paid to the resonant case in which the motion of the particle is unbounded. -- Highlights: •We study a relativistic electron in a particular electromagnetic field configuration. •New exact solutions of the Klein–Gordon and Dirac equations are obtained. •Coherent and displaced number states can describe a relativistic particle.

  1. Fluorescence quenching of quantum dots by gold nanoparticles: a potential long range spectroscopic ruler.

    PubMed

    Samanta, Anirban; Zhou, Yadong; Zou, Shengli; Yan, Hao; Liu, Yan

    2014-09-10

    The dependence of quantum dot (QD) fluorescence emission on the proximity of 30 nm gold nanoparticles (AuNPs) was studied with controlled interparticle distances ranging from 15 to 70 nm. This was achieved by coassembling DNA-conjugated QDs and AuNPs in a 1:1 ratio at precise positions on a triangular-shaped DNA origami platform. A profound, long-range quenching of the photoluminescence intensity of the QDs was observed. A combination of static and time-resolved fluorescence measurements suggests that the quenching is due to an increase in the nonradiative decay rate of QD emission. Unlike FRET, the energy transfer is inversely proportional to the 2.7th power of the distance between nanoparticles with half quenching at ∼28 nm. This long-range quenching phenomena may be useful for developing extended spectroscopic rulers in the future. PMID:25084363

  2. Relativistically strong electromagnetic radiation in a plasma

    NASA Astrophysics Data System (ADS)

    Bulanov, S. V.; Esirkepov, T. Zh.; Kando, M.; Kiriyama, H.; Kondo, K.

    2016-03-01

    Physical processes in a plasma under the action of relativistically strong electromagnetic waves generated by high-power lasers have been briefly reviewed. These processes are of interest in view of the development of new methods for acceleration of charged particles, creation of sources of bright hard electromagnetic radiation, and investigation of macroscopic quantum-electrodynamical processes. Attention is focused on nonlinear waves in a laser plasma for the creation of compact electron accelerators. The acceleration of plasma bunches by the radiation pressure of light is the most efficient regime of ion acceleration. Coherent hard electromagnetic radiation in the relativistic plasma is generated in the form of higher harmonics and/or electromagnetic pulses, which are compressed and intensified after reflection from relativistic mirrors created by nonlinear waves. In the limit of extremely strong electromagnetic waves, radiation friction, which accompanies the conversion of radiation from the optical range to the gamma range, fundamentally changes the behavior of the plasma. This process is accompanied by the production of electron-positron pairs, which is described within quantum electrodynamics theory.

  3. Relativistic nuclear dynamics

    SciTech Connect

    Coester, F.

    1985-01-01

    A review is presented of three distinct approaches to the construction of relativistic dynamical models: (1) Relativistic canonical quantum mechanics. (The Hilbert space of states is independent of the interactions, which are introduced by modifying the energy operator.) (2) Hilbert spaces of manifestly covariant wave functions. (The interactions modify the metric of the Hilbert space.) (3) Covariant Green functions. In each of the three approaches the focus is on the formulation of the two-body dynamics, and problems in the construction of the corresponding many-body dynamics are discussed briefly. 21 refs.

  4. High performance, low dissipation quantum cascade lasers across the mid-IR range.

    PubMed

    Bismuto, Alfredo; Blaser, Stéphane; Terazzi, Romain; Gresch, Tobias; Muller, Antoine

    2015-03-01

    In this work, we present the development of low consumption quantum cascade lasers across the mid-IR range. In particular, short cavity single-mode lasers with optimised facet reflectivities have been fabricated from 4.5 to 9.2 μm. Threshold dissipated powers as low as 0.5 W were obtained in continuous wave operation at room temperature. In addition, the beneficial impact of reducing chip length on laser mounting yield is discussed. High power single-mode lasers from the same processed wafers are also presented.

  5. Magnon-induced long-range correlations and their neutron-scattering signature in quantum magnets

    NASA Astrophysics Data System (ADS)

    Bharadwaj, S.; Belitz, D.; Kirkpatrick, T. R.

    2016-10-01

    We consider the coupling of the magnetic Goldstone modes, or magnons, in both quantum ferromagnets and antiferromagnets to the longitudinal order-parameter fluctuations and the resulting nonanalytic behavior of the longitudinal susceptibility. In classical magnets it is well known that long-range correlations induced by the magnons lead to a singular wave-number dependence of the form 1 /k4 -d in all dimensions 2 quantum antiferromagnet scales as kd -3 for 1 quantum ferromagnet the analogous result, kd -2, is absent due to a zero scaling function. This absence of a nonanalyticity in the longitudinal susceptibility is due to the lack of magnon number fluctuations in the ground state of a quantum ferromagnet; correlation functions that are sensitive to other fluctuations do exhibit the behavior predicted by simple power counting. Also of interest is the dynamical behavior as expressed in the longitudinal part of the dynamical structure factor, which is directly measurable via neutron scattering. For both ferromagnets and antiferromagnets there is a logarithmic singularity at the magnon frequency with a prefactor that vanishes as T →0 . In addition, in the antiferromagnetic case there is a nonzero contribution at T =0 that is missing for ferromagnets. Magnon damping due to quenched disorder restores the expected scaling behavior of the longitudinal susceptibility in the ferromagnetic case; it scales as kd -2 if the order parameter is not conserved (magnetic disorder), or as kd if it is (nonmagnetic disorder). Detailed predictions are made for both two- and three-dimensional systems at both T =0 and in the limit of low temperatures, and the physics behind the various nonanalytic behaviors is discussed.

  6. Short-range interactions and scaling near integer quantum Hall transitions

    SciTech Connect

    Wang, Ziqiang; Fisher, Matthew P. A.; Girvin, S. M.; Chalker, J. T.

    2000-03-15

    We study the influence of short-range electron-electron interactions on scaling behavior near the integer quantum Hall plateau transitions. Short-range interactions are known to be irrelevant at the renormalization group fixed point which represents the transition in the noninteracting system. We find, nevertheless, that transport properties change discontinuously when interactions are introduced. Most importantly, in the thermodynamic limit the conductivity at finite temperature is zero without interactions, but nonzero in the presence of arbitrarily weak interactions. In addition, scaling as a function of frequency {omega} and temperature T is determined by the scaling variable {omega}/T{sup p} (where p is the exponent for the temperature dependence of the inelastic scattering rate) and not by {omega}/T, as it would be at a conventional quantum phase transition described by an interacting fixed point. We express the inelastic exponent p and the thermal exponent z{sub T} in terms of the scaling dimension -{alpha}<0 of the interaction strength and the dynamical exponent z (which has the value z=2), obtaining p=1+2{alpha}/z and z{sub T}=2/p. (c) 2000 The American Physical Society.

  7. Broadband tuning of continuous wave quantum cascade lasers in long wavelength (> 10 μm) range.

    PubMed

    Dougakiuchi, Tatsuo; Fujita, Kazuue; Sugiyama, Atsushi; Ito, Akio; Akikusa, Naota; Edamura, Tadataka

    2014-08-25

    Broadband spectral tuning in the long wavelength range (greater than 10 μm) was demonstrated with an external-cavity quantum cascade laser. The tunable wavelength of the laser ranged from 9.5 to 11.4 μm (176 cm(-1); corresponding to 18% of the center wavelength) in continuous wave (cw) operation at room temperature, without any anti-reflection coating. The gain chip based on the anti-crossed dual-upper-state (DAU) design provided a cw lasing up to 300 K, with a low threshold current density of 2.1 kA/cm2. The highly stable broadband spectral tuning and high laser performance were enabled by the spectrally homogeneous gain profile of the anti-crossed DAU active region.

  8. Kaleidoscope of quantum phases in a long-range interacting spin-1 chain

    NASA Astrophysics Data System (ADS)

    Gong, Z.-X.; Maghrebi, M. Â. F.; Hu, A.; Foss-Feig, M.; Richerme, P.; Monroe, C.; Gorshkov, A. Â. V.

    2016-05-01

    Motivated directly by recent trapped-ion quantum simulation experiments, we carry out a comprehensive study of the phase diagram of a spin-1 chain with XXZ-type interactions that decay as 1 /rα , using a combination of finite and infinite-size DMRG calculations, spin-wave analysis, and field theory. In the absence of long-range interactions, varying the spin-coupling anisotropy leads to four distinct and well-studied phases: a ferromagnetic Ising phase, a disordered XY phase, a topological Haldane phase, and an antiferromagnetic Ising phase. If long-range interactions are antiferromagnetic and thus frustrated, we find primarily a quantitative change of the phase boundaries. On the other hand, ferromagnetic (nonfrustrated) long-range interactions qualitatively impact the entire phase diagram. Importantly, for α ≲3 , long-range interactions destroy the Haldane phase, break the conformal symmetry of the XY phase, give rise to a new phase that spontaneously breaks a U (1 ) continuous symmetry, and introduce a possibly exotic tricritical point with no direct parallel in short-range interacting spin chains. Importantly, we show that the main signatures of all five phases found could be observed experimentally in the near future.

  9. Isotope shifts of the three lowest 1S states of the B+ ion calculated with a finite-nuclear-mass approach and with relativistic and quantum electrodynamics corrections.

    PubMed

    Bubin, Sergiy; Komasa, Jacek; Stanke, Monika; Adamowicz, Ludwik

    2010-03-21

    We present very accurate quantum mechanical calculations of the three lowest S-states [1s(2)2s(2)((1)S(0)), 1s(2)2p(2)((1)S(0)), and 1s(2)2s3s((1)S(0))] of the two stable isotopes of the boron ion, (10)B(+) and (11)B(+). At the nonrelativistic level the calculations have been performed with the Hamiltonian that explicitly includes the finite mass of the nucleus as it was obtained by a rigorous separation of the center-of-mass motion from the laboratory frame Hamiltonian. The spatial part of the nonrelativistic wave function for each state was expanded in terms of 10,000 all-electron explicitly correlated Gaussian functions. The nonlinear parameters of the Gaussians were variationally optimized using a procedure involving the analytical energy gradient determined with respect to the nonlinear parameters. The nonrelativistic wave functions of the three states were subsequently used to calculate the leading alpha(2) relativistic corrections (alpha is the fine structure constant; alpha=1/c, where c is the speed of light) and the alpha(3) quantum electrodynamics (QED) correction. We also estimated the alpha(4) QED correction by calculating its dominant component. A comparison of the experimental transition frequencies with the frequencies obtained based on the energies calculated in this work shows an excellent agreement. The discrepancy is smaller than 0.4 cm(-1).

  10. Isotope shifts of the three lowest 1S states of the B+ ion calculated with a finite-nuclear-mass approach and with relativistic and quantum electrodynamics corrections

    NASA Astrophysics Data System (ADS)

    Bubin, Sergiy; Komasa, Jacek; Stanke, Monika; Adamowicz, Ludwik

    2010-03-01

    We present very accurate quantum mechanical calculations of the three lowest S-states [1s22s2(S10), 1s22p2(S10), and 1s22s3s(S10)] of the two stable isotopes of the boron ion, B10+ and B11+. At the nonrelativistic level the calculations have been performed with the Hamiltonian that explicitly includes the finite mass of the nucleus as it was obtained by a rigorous separation of the center-of-mass motion from the laboratory frame Hamiltonian. The spatial part of the nonrelativistic wave function for each state was expanded in terms of 10 000 all-electron explicitly correlated Gaussian functions. The nonlinear parameters of the Gaussians were variationally optimized using a procedure involving the analytical energy gradient determined with respect to the nonlinear parameters. The nonrelativistic wave functions of the three states were subsequently used to calculate the leading α2 relativistic corrections (α is the fine structure constant; α =1/c, where c is the speed of light) and the α3 quantum electrodynamics (QED) correction. We also estimated the α4 QED correction by calculating its dominant component. A comparison of the experimental transition frequencies with the frequencies obtained based on the energies calculated in this work shows an excellent agreement. The discrepancy is smaller than 0.4 cm-1.

  11. Long-range energy transfer in self-assembled quantum dot-DNA cascades

    NASA Astrophysics Data System (ADS)

    Goodman, Samuel M.; Siu, Albert; Singh, Vivek; Nagpal, Prashant

    2015-11-01

    The size-dependent energy bandgaps of semiconductor nanocrystals or quantum dots (QDs) can be utilized in converting broadband incident radiation efficiently into electric current by cascade energy transfer (ET) between layers of different sized quantum dots, followed by charge dissociation and transport in the bottom layer. Self-assembling such cascade structures with angstrom-scale spatial precision is important for building realistic devices, and DNA-based QD self-assembly can provide an important alternative. Here we show long-range Dexter energy transfer in QD-DNA self-assembled single constructs and ensemble devices. Using photoluminescence, scanning tunneling spectroscopy, current-sensing AFM measurements in single QD-DNA cascade constructs, and temperature-dependent ensemble devices using TiO2 nanotubes, we show that Dexter energy transfer, likely mediated by the exciton-shelves formed in these QD-DNA self-assembled structures, can be used for efficient transport of energy across QD-DNA thin films.The size-dependent energy bandgaps of semiconductor nanocrystals or quantum dots (QDs) can be utilized in converting broadband incident radiation efficiently into electric current by cascade energy transfer (ET) between layers of different sized quantum dots, followed by charge dissociation and transport in the bottom layer. Self-assembling such cascade structures with angstrom-scale spatial precision is important for building realistic devices, and DNA-based QD self-assembly can provide an important alternative. Here we show long-range Dexter energy transfer in QD-DNA self-assembled single constructs and ensemble devices. Using photoluminescence, scanning tunneling spectroscopy, current-sensing AFM measurements in single QD-DNA cascade constructs, and temperature-dependent ensemble devices using TiO2 nanotubes, we show that Dexter energy transfer, likely mediated by the exciton-shelves formed in these QD-DNA self-assembled structures, can be used for efficient

  12. Relativistic impulse dynamics.

    PubMed

    Swanson, Stanley M

    2011-08-01

    Classical electrodynamics has some annoying rough edges. The self-energy of charges is infinite without a cutoff. The calculation of relativistic trajectories is difficult because of retardation and an average radiation reaction term. By reconceptuallizing electrodynamics in terms of exchanges of impulses rather than describing it by forces and potentials, we eliminate these problems. A fully relativistic theory using photonlike null impulses is developed. Numerical calculations for a two-body, one-impulse-in-transit model are discussed. A simple relationship between center-of-mass scattering angle and angular momentum was found. It reproduces the Rutherford cross section at low velocities and agrees with the leading term of relativistic distinguishable-particle quantum cross sections (Møller, Mott) when the distance of closest approach is larger than the Compton wavelength of the particle. Magnetism emerges as a consequence of viewing retarded and advanced interactions from the vantage point of an instantaneous radius vector. Radiation reaction becomes the local conservation of energy-momentum between the radiating particle and the emitted impulse. A net action is defined that could be used in developing quantum dynamics without potentials. A reinterpretation of Newton's laws extends them to relativistic motion.

  13. Relativistic shell model calculations

    NASA Astrophysics Data System (ADS)

    Furnstahl, R. J.

    1986-06-01

    Shell model calculations are discussed in the context of a relativistic model of nuclear structure based on renormalizable quantum field theories of mesons and baryons (quantum hadrodynamics). The relativistic Hartree approximation to the full field theory, with parameters determined from bulk properties of nuclear matter, predicts a shell structure in finite nuclei. Particle-hole excitations in finite nuclei are described in an RPA calculation based on this QHD ground state. The particle-hole interaction is prescribed by the Hartree ground state, with no additional parameters. Meson retardation is neglected in deriving the RPA equations, but it is found to have negligible effects on low-lying states. The full Dirac matrix structure is maintained throughout the calculation; no nonrelativistic reductions are made. Despite sensitive cancellations in the ground state calculation, reasonable excitation spectra are obtained for light nuclei. The effects of including charged mesons, problems with heavy nuclei, and prospects for improved and extended calculations are discussed.

  14. Unitary S matrices with long-range correlations and the quantum black hole

    NASA Astrophysics Data System (ADS)

    Akhoury, Ratindranath

    2014-08-01

    We propose an S matrix approach to the quantum black hole in which causality, unitarity and their interrelation play a prominent role. Assuming the 't Hooft S matrix ansatz for a gravitating region surrounded by an asymptotically flat space-time we find a non-local transformation which changes the standard causality requirement but is a symmetry of the unitarity condition of the S matrix. This new S matrix then implies correlations between the in and out states of the theory with the involvement of a third entity which in the case of a quantum black hole, we argue is the horizon S matrix. Effects of spacetime curvature and horizon are in fact introduced by this procedure which is seen to be a generalization of the Bogoliubov transformation. The analysis is performed within the Bogoliubov S matrix framework by considering a spacetime consisting of causal complements with a boundary in between. No particular metric or lagrangian dynamics need be invoked even to obtain an evolution equation for the full S matrix. Hawking's results are reproduced by restricting to low energy incoming modes at the horizon and the generalized hamiltonian of the horizon S matrix in this case is shown to be the generator of the Bogoliubov transformation. The modification of Bogoliubov causality at intermediate stages of black hole evaporation allows for a temporary violation of quantum mechanical no cloning theorems. In this way we find that the tension between information preservation and complementarity may be resolved provided the full quantum gravity theory either through symmetries or fine tuning forbids the occurrence of closed time like curves of information flow. Then, even if causality is violated near the horizon at any intermediate stage, a standard causal ordering may be preserved for the observer outside the black hole. The usefulness of our formulation is that it appears well suited to understand unitarity at any intermediate stage of black hole evaporation. Moreover, it is

  15. Superconducting quantum magnetometer for the range 1-200/sup 0/K

    SciTech Connect

    Khlyustikov, I.N.

    1985-06-01

    A description is given of a superconducting quantum magnetometer for the range 1-200/sup 0/K. The receiving coil in the lead superconducting flux transformer is thermally insulated from the heated specimen by a high-vacuum gap. The temperature of the specimen is controlled by a manganin wire heater, while that of the magnetometric part of the instrument is kept at about 2/sup 0/K. This method of varying the specimen temperture enables one to measure the part of the magnetic moment of the specimen that is nonlinearly dependent on the field and temperature, and also to measure the field-independent part of the susceptibility as a function of temperature with a sensitivity in the magnetometer of about 10/sup -17/ Wb.

  16. Relativistic viscoelastic fluid mechanics

    SciTech Connect

    Fukuma, Masafumi; Sakatani, Yuho

    2011-08-15

    A detailed study is carried out for the relativistic theory of viscoelasticity which was recently constructed on the basis of Onsager's linear nonequilibrium thermodynamics. After rederiving the theory using a local argument with the entropy current, we show that this theory universally reduces to the standard relativistic Navier-Stokes fluid mechanics in the long time limit. Since effects of elasticity are taken into account, the dynamics at short time scales is modified from that given by the Navier-Stokes equations, so that acausal problems intrinsic to relativistic Navier-Stokes fluids are significantly remedied. We in particular show that the wave equations for the propagation of disturbance around a hydrostatic equilibrium in Minkowski space-time become symmetric hyperbolic for some range of parameters, so that the model is free of acausality problems. This observation suggests that the relativistic viscoelastic model with such parameters can be regarded as a causal completion of relativistic Navier-Stokes fluid mechanics. By adjusting parameters to various values, this theory can treat a wide variety of materials including elastic materials, Maxwell materials, Kelvin-Voigt materials, and (a nonlinearly generalized version of) simplified Israel-Stewart fluids, and thus we expect the theory to be the most universal description of single-component relativistic continuum materials. We also show that the presence of strains and the corresponding change in temperature are naturally unified through the Tolman law in a generally covariant description of continuum mechanics.

  17. Relativistic viscoelastic fluid mechanics.

    PubMed

    Fukuma, Masafumi; Sakatani, Yuho

    2011-08-01

    A detailed study is carried out for the relativistic theory of viscoelasticity which was recently constructed on the basis of Onsager's linear nonequilibrium thermodynamics. After rederiving the theory using a local argument with the entropy current, we show that this theory universally reduces to the standard relativistic Navier-Stokes fluid mechanics in the long time limit. Since effects of elasticity are taken into account, the dynamics at short time scales is modified from that given by the Navier-Stokes equations, so that acausal problems intrinsic to relativistic Navier-Stokes fluids are significantly remedied. We in particular show that the wave equations for the propagation of disturbance around a hydrostatic equilibrium in Minkowski space-time become symmetric hyperbolic for some range of parameters, so that the model is free of acausality problems. This observation suggests that the relativistic viscoelastic model with such parameters can be regarded as a causal completion of relativistic Navier-Stokes fluid mechanics. By adjusting parameters to various values, this theory can treat a wide variety of materials including elastic materials, Maxwell materials, Kelvin-Voigt materials, and (a nonlinearly generalized version of) simplified Israel-Stewart fluids, and thus we expect the theory to be the most universal description of single-component relativistic continuum materials. We also show that the presence of strains and the corresponding change in temperature are naturally unified through the Tolman law in a generally covariant description of continuum mechanics.

  18. Effective theory and breakdown of conformal symmetry in a long-range quantum chain

    NASA Astrophysics Data System (ADS)

    Lepori, L.; Vodola, D.; Pupillo, G.; Gori, G.; Trombettoni, A.

    2016-11-01

    We deal with the problem of studying the symmetries and the effective theories of long-range models around their critical points. A prominent issue is to determine whether they possess (or not) conformal symmetry (CS) at criticality and how the presence of CS depends on the range of the interactions. To have a model, both simple to treat and interesting, where to investigate these questions, we focus on the Kitaev chain with long-range pairings decaying with distance as power-law with exponent α. This is a quadratic solvable model, yet displaying non-trivial quantum phase transitions. Two critical lines are found, occurring respectively at a positive and a negative chemical potential. Focusing first on the critical line at positive chemical potential, by means of a renormalization group approach we derive its effective theory close to criticality. Our main result is that the effective action is the sum of two terms: a Dirac action SD, found in the short-range Ising universality class, and an "anomalous" CS breaking term SAN. While SD originates from low-energy excitations in the spectrum, SAN originates from the higher energy modes where singularities develop, due to the long-range nature of the model. At criticality SAN flows to zero for α > 2, while for α < 2 it dominates and determines the breakdown of the CS. Out of criticality SAN breaks, in the considered approximation, the effective Lorentz invariance (ELI) for every finite α. As α increases such ELI breakdown becomes less and less pronounced and in the short-range limit α → ∞ the ELI is restored. In order to test the validity of the determined effective theory, we compared the two-fermion static correlation functions and the von Neumann entropy obtained from them with the ones calculated on the lattice, finding agreement. These results explain two observed features characteristic of long-range models, the hybrid decay of static correlation functions within gapped phases and the area-law violation

  19. Self-modulation of a long externally injected relativistic charged-particle beam in a laser wake field acceleration scheme. A preliminary quantum-like investigation

    NASA Astrophysics Data System (ADS)

    Fedele, Renato; Jovanović, Dusan; Tanjia, Fatema; De Nicola, Sergio

    2014-03-01

    Recent investigations indicate that sufficiently long beams of charged particles, travelling in a plasma, experience the phenomenon of self-modulation. The self-modulation is driven by the plasma wake field excitation due to the beam itself, and it may become unstable under certain conditions. A preliminary theoretical investigation of the self-modulation of a relativistic charged-particle beam in overdense plasma in the presence of a preformed plasma wave is carried out, within the quantum-like description of charged particle beams provided by the Thermal Wave Model. A simple physical model for the self-modulation is put forward, described by a nonlinear Schrödinger equation coupled with the Poisson-like equation for the plasma wake potential (so-called Fedele-Shukla equations). The physical mechanism is based on the interplay of three concomitant effects, the radial thermal dispersion (associated with the emittance ε), the radial ponderomotive effects of a preexisting plasma wave (which provides the guidance for the beam), and the self-interaction of the plasma wake field generated by the beam itself.

  20. Formation of long-range ordered quantum dots arrays in amorphous matrix by ion beam irradiation

    SciTech Connect

    Buljan, M.; Bogdanovic-Radovic, I.; Karlusic, M.; Desnica, U. V.; Radic, N.; Dubcek, P.; Drazic, G.; Salamon, K.; Bernstorff, S.; Holy, V.

    2009-08-10

    We demonstrate the production of a well ordered three-dimensional array of Ge quantum dots in amorphous silica matrix. The ordering is achieved by ion beam irradiation and annealing of a multilayer film. Structural analysis shows that quantum dots nucleate along the direction of the ion beam used for irradiation, while the mutual distance of the quantum dots is determined by the diffusion properties of the multilayer material rather than the distances between traces of ions that are used for irradiation.

  1. Direct Imaging of Long-Range Exciton Transport in Quantum Dot Superlattices by Ultrafast Microscopy.

    PubMed

    Yoon, Seog Joon; Guo, Zhi; Dos Santos Claro, Paula C; Shevchenko, Elena V; Huang, Libai

    2016-07-26

    Long-range charge and exciton transport in quantum dot (QD) solids is a crucial challenge in utilizing QDs for optoelectronic applications. Here, we present a direct visualization of exciton diffusion in highly ordered CdSe QDs superlattices by mapping exciton population using ultrafast transient absorption microscopy. A temporal resolution of ∼200 fs and a spatial precision of ∼50 nm of this technique provide a direct assessment of the upper limit for exciton transport in QD solids. An exciton diffusion length of ∼125 nm has been visualized in the 3 ns experimental time window and an exciton diffusion coefficient of (2.5 ± 0.2) × 10(-2) cm(2) s(-1) has been measured for superlattices constructed from 3.6 nm CdSe QDs with center-to-center distance of 6.7 nm. The measured exciton diffusion constant is in good agreement with Förster resonance energy transfer theory. We have found that exciton diffusion is greatly enhanced in the superlattices over the disordered films with an order of magnitude higher diffusion coefficient, pointing toward the role of disorder in limiting transport. This study provides important understandings on energy transport mechanisms in both the spatial and temporal domains in QD solids. PMID:27387010

  2. Symmetry energy of cold nucleonic matter within a relativistic mean field model encapsulating effects of high-momentum nucleons induced by short-range correlations

    NASA Astrophysics Data System (ADS)

    Cai, Bao-Jun; Li, Bao-An

    2016-01-01

    It is well known that short-range nucleon-nucleon correlations (SRC) from the tensor components and/or the repulsive core of nuclear forces lead to a high- (low-)momentum tail (depletion) in the single-nucleon momentum distribution above (below) the nucleon Fermi surface in cold nucleonic matter. Significant progress was made recently in constraining the isospin-dependent parameters characterizing the SRC-modified single-nucleon momentum distribution in neutron-rich nucleonic matter using both experimental data and microscopic model calculations. Using the constrained single-nucleon momentum distribution in a nonlinear relativistic mean field (RMF) model, we study the equation of state (EOS) of asymmetric nucleonic matter (ANM), especially the density dependence of nuclear symmetry energy Esym(ρ ) . First, as a test of the model, the average nucleon kinetic energy extracted recently from electron-nucleus scattering experiments using a neutron-proton dominance model is well reproduced by the RMF model incorporating effects of the SRC-induced high-momentum nucleons, while it is significantly under predicted by the RMF model using a step function for the single-nucleon momentum distribution as in free Fermi gas (FFG) models. Second, consistent with earlier findings within nonrelativistic models, the kinetic symmetry energy of quasinucleons is found to be Esymkin(ρ0) =-16.94 ±13.66 MeV which is dramatically different from the prediction of Esymkin(ρ0) ≈12.5 MeV by FFG models at nuclear matter saturation density ρ0=0.16 fm-3 . Third, comparing the RMF calculations with and without the high-momentum nucleons using two sets of model parameters both reproducing identically all empirical constraints on the EOS of symmetric nuclear matter (SNM) and the symmetry energy of ANM at ρ0, the SRC-modified single-nucleon momentum distribution is found to make the Esym(ρ ) more concave around ρ0 by softening it significantly at both subsaturation and suprasaturation

  3. Long-range entanglement is necessary for a topological storage of quantum information.

    PubMed

    Kim, Isaac H

    2013-08-23

    A general inequality between entanglement entropy and a number of topologically ordered states is derived, even without using the properties of the parent Hamiltonian or the formalism of topological quantum field theory. Given a quantum state |ψ], we obtain an upper bound on the number of distinct states that are locally indistinguishable from |ψ]. The upper bound is determined only by the entanglement entropy of some local subsystems. As an example, we show that log N≤2γ for a large class of topologically ordered systems on a torus, where N is the number of topologically protected states and γ is the constant subcorrection term of the entanglement entropy. We discuss applications to quantum many-body systems that do not have any low-energy topological quantum field theory description, as well as tradeoff bounds for general quantum error correcting codes.

  4. Study of the Spectral Properties of Nanocomposites with CdSe Quantum Dots in a Wide Range of Low Temperatures

    NASA Astrophysics Data System (ADS)

    Magaryan, K. A.; Eremchev, I. Y.; Karimullin, K. R.; Knyazev, M. V.; Mikhailov, M. A.; Vasilieva, I. A.; Klimusheva, G. V.

    2015-09-01

    Luminescence spectra of the colloidal solution of CdSe quantum dots (in toluene) were studied in a wide range of low temperatures. Samples were synthesized in the liquid crystal matrix of cadmium octanoate (CdC8). A comparative analysis of the obtained data with previous results was performed.

  5. The infinite-range quantum transverse Ising spin glass: new estimate of the critical line via thermo-field method

    NASA Astrophysics Data System (ADS)

    Kopeć, T. K.; Büttner, G.; Usadel, K. D.

    1990-10-01

    The infinite-range quantum Ising spin glass in a transverse field Γ is studied by means of the thermo-field dynamics as a substitute for the n-replica trick. A new estimate of the critical line Tc(Γ) is obtained by the improved treatment of the dynamic self-interaction - in considerable agreement with the Trotter-Suzuki method.

  6. A Mathematica package for calculation of planar channeling radiation spectra of relativistic electrons channeled in a diamond-structure single crystal (quantum approach)

    NASA Astrophysics Data System (ADS)

    Azadegan, B.

    2013-03-01

    The presented Mathematica code is an efficient tool for simulation of planar channeling radiation spectra of relativistic electrons channeled along major crystallographic planes of a diamond-structure single crystal. The program is based on the quantum theory of channeling radiation which has been successfully applied to study planar channeling at electron energies between 10 and 100 MeV. Continuum potentials for different planes of diamond, silicon and germanium single crystals are calculated using the Doyle-Turner approximation to the atomic scattering factor and taking thermal vibrations of the crystal atoms into account. Numerical methods are applied to solve the one-dimensional Schrödinger equation. The code is designed to calculate the electron wave functions, transverse electron states in the planar continuum potential, transition energies, line widths of channeling radiation and depth dependencies of the population of quantum states. Finally the spectral distribution of spontaneously emitted channeling radiation is obtained. The simulation of radiation spectra considerably facilitates the interpretation of experimental data. Catalog identifier: AEOH_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEOH_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 446 No. of bytes in distributed program, including test data, etc.: 209805 Distribution format: tar.gz Programming language: Mathematica. Computer: Platforms on which Mathematica is available. Operating system: Operating systems on which Mathematica is available. RAM: 1 MB Classification: 7.10. Nature of problem: Planar channeling radiation is emitted by relativistic charged particles during traversing a single crystal in direction parallel to a crystallographic plane. Channeling is modeled as the motion

  7. Spreading of correlations in exactly solvable quantum models with long-range interactions in arbitrary dimensions

    NASA Astrophysics Data System (ADS)

    Cevolani, Lorenzo; Carleo, Giuseppe; Sanchez-Palencia, Laurent

    2016-09-01

    We study the out-of-equilibrium dynamics induced by quantum quenches in quadratic Hamiltonians featuring both short- and long-range interactions. The spreading of correlations in the presence of algebraic decaying interactions, 1/R α , is studied for lattice Bose models in arbitrary dimension D. These models are exactly solvable and provide useful insight in the universal description of more complex systems as well as comparisons to the known universal upper bounds for the spreading of correlations. Using analytical calculations of the dominant terms and full numerical integration of all quasi-particle contributions, we identify three distinct dynamical regimes. For strong decay of interactions, α \\gt D+1, we find a causal regime, qualitatively similar to what previously found for short-range interactions. This regime is characterized by ballistic (linear cone) spreading of the correlations with a cone velocity equal to twice the maximum group velocity of the quasi-particles. For weak decay of interactions, α < D, we find instantaneous activation of correlations at arbitrary distance. This signals the breaking of causality, which can be associated with the divergence of the quasi-particle energy spectrum. Finite-size scaling of the activation time precisely confirms this interpretation. For intermediate decay of interactions, D\\lt α \\lt D+1, we find a sub-ballistic, algebraic (bent cone) spreading and determine the corresponding exponent as a function of α. These outcomes generalize existing results for one-dimensional systems to arbitrary dimension. We precisely relate the three regimes to the first- and second-order divergences of the quasi-particle energy spectrum for any dimension. The long-range transverse Ising model in dimensions D = 1, 2, and 3 in the (quadratic) spin-wave approximation is more specifically studied and we also discuss the shape of the correlation front in dimension higher than one. Our results apply to several condensed

  8. SAMPEX Relativistic Microbursts Observation

    NASA Astrophysics Data System (ADS)

    Liang, X.; Comess, M.; Smith, D. M.; Selesnick, R. S.; Sample, J. G.; Millan, R. M.

    2012-12-01

    Relativistic (>1 MeV) electron microburst precipitation is thought to account for significant relativistic electron loss. We present the statistical and spectral analysis of relativistic microbursts observed by the Proton/Electron Telescope (PET) on board the Solar Anomalous Magnetospheric Particle Explorer(SAMPEX) satellite from 1992 to 2004. Spectrally we find that microbursts are well fit by an exponential energy distribution in the 0.5-4 MeV range with a spectral e-folding energy of E0 < 375 keV. We also discuss the comparison of morning microbursts with events at midnight, which were first identified as microbursts by O'Brien et al. (2004). Finally, we compare the loss-rates due to microbursts and non-microburst precipitation during storm times and averaged over all times.

  9. A grating-coupled external cavity InAs/InP quantum dot laser with 85-nm tuning range

    NASA Astrophysics Data System (ADS)

    Wei, Heng; Jin, Peng; Luo, Shuai; Ji, Hai-Ming; Yang, Tao; Li, Xin-Kun; Wu, Jian; An, Qi; Wu, Yan-Hua; Chen, Hong-Mei; Wang, Fei-Fei; Wu, Ju; Wang, Zhan-Guo

    2013-09-01

    The optical performance of a grating-coupled external cavity laser based on InAs/InP quantum dots is investigated. Continuous tuning from 1391 nm to 1468 nm is realized at an injection current of 1900 mA. With the injection current increasing to 2300 mA, the tuning is blue shifted to some extent to the range from 1383 nm to 1461 nm. By combining the effect of the injection current with the grating tuning, the total tuning bandwidth of the external cavity quantum-dot laser can reach up to 85 nm. The dependence of the threshold current on the tuning wavelength is also presented.

  10. Classical Simulation of Relativistic Zitterbewegung in Photonic Lattices

    SciTech Connect

    Dreisow, Felix; Heinrich, Matthias; Keil, Robert; Tuennermann, Andreas; Nolte, Stefan; Longhi, Stefano; Szameit, Alexander

    2010-10-01

    We present the first experimental realization of an optical analog for relativistic quantum mechanics by simulating the Zitterbewegung (trembling motion) of a free Dirac electron in an optical superlattice. Our photonic setting enables a direct visualization of Zitterbewegung as a spatial oscillatory motion of an optical beam. Direct measurements of the wave packet expectation values in superlattices with tuned miniband gaps clearly show the transition from weak-relativistic to relativistic and far-relativistic regimes.

  11. Scattering in Relativistic Particle Mechanics.

    NASA Astrophysics Data System (ADS)

    de Bievre, Stephan

    Fokker's action principle. To study the Moller operators in the manifestly covariant approach, we extend techniques developed for dealing with non-relativistic two-body scattering and determine precise conditions on the dynamical vectorfields under which the Moller operators can be proven to exist. We then show how Moller operators can be used to construct the Hamiltonian structure in the manifestly covariant approach. Finally, we turn our attention to the quantization of the models discussed. We determine a notion of position in a model for the quantum mechanical treatment of the free relativistic particle that does not violate causality. This result must be compared to recent proofs of the fact that the notions of strict localization and of causality are not mutually compatible in relativistic quantum mechanics. (Abstract shortened with permission of author.).

  12. PREFACE: The Quantum Universe

    NASA Astrophysics Data System (ADS)

    Adler, Stephen L.; Bassi, Angelo; Dowker, Fay; Dürr, Detlef

    2007-03-01

    This special issue of Journal of Physics A: Mathematical and Theoretical entitled 'The Quantum Universe' is dedicated to Professor Giancarlo Ghirardi on the occasion of his 70th birthday. Giancarlo Ghirardi has made many important contributions to the foundations of quantum mechanics including the celebrated Ghirardi Rimini Weber (GRW) model of spontaneous wavefunction collapse. However, although Professor Ghirardi's birthday is the inspiration for this issue, it has a much broader scope than the area traditionally known as Foundations of Quantum Mechanics. All invited authors are experts in areas of physics in which quantum theory is fundamental: non relativistic quantum mechanics, quantum computation and information, quantum field theory, quantum gravity, quantum cosmology and philosophy of science. The issue was conceived as an opportunity for workers in these diverse areas to share with the widest possible readership their views on quantum theory. Authors were encouraged to give their personal assessment of the role of quantum theory in their work particularly as it pertains to a vision of the global aims of their research. The articles are accessible to any physicist with a solid knowledge of quantum mechanics, and many contain an emphasis on conceptual developments, both those achieved and those hoped for. One theme that runs throughout Giancarlo Ghirardi's contributions to science is the unity of physics: the development of the GRW model itself was motivated by the conviction that the same physics should govern microscopic and macroscopic systems. However, readers of this special issue will clearly see that there is no unity as yet in the views of workers on fundamental quantum theories. Indeed the diversity of the articles, ranging from technical developments in well defined approaches, to new proposals for interpretations of quantum mechanics, indicates the state of fundamental physics: healthily active and yet lacking the consensus we seek in science

  13. Energy Dependence of Directed Flow over a Wide Range of Pseudorapidity in Au+Au Collisions at the BNL Relativistic Heavy Ion Collider

    SciTech Connect

    Back, B.B.; Wuosmaa, A.H.; Baker, M.D.; Barton, D.S.; Carroll, A.; Chai, Z.; Gushue, S.; Hauer, M.; Heintzelman, G.A.; Holzman, B.; Pak, R.; Remsberg, L.P.; Seals, H.; Sedykh, I.; Stankiewicz, M.A.; Steinberg, P.; Sukhanov, A.; Ballintijn, M.; Busza, W.; Decowski, M.P.

    2006-07-07

    We report on measurements of directed flow as a function of pseudorapidity in Au+Au collisions at energies of {radical}(s{sub NN})=19.6, 62.4, 130 and 200 GeV as measured by the PHOBOS detector at the BNL Relativistic Heavy Ion Collider. These results are particularly valuable because of the extensive, continuous pseudorapidity coverage of the PHOBOS detector. There is no significant indication of structure near midrapidity and the data surprisingly exhibit extended longitudinal scaling similar to that seen for elliptic flow and charged particle pseudorapidity density.

  14. Range-dependent effects of optical feedback on multimode two-color quantum dot lasers

    NASA Astrophysics Data System (ADS)

    Virte, Martin; Pawlus, Robert; Elsäßer, Wolfgang; Panajotov, Krassimir; Sciamanna, Marc; Breuer, Stefan

    2016-04-01

    We investigate the behaviour of a multimode two-color quantum dot laser subject to optical feedback. In particular, we focus on the effects of a variation of the external cavity length at the micrometer scale on the laser emission characteristics and especially on its optical spectrum. For each mode, we observe oscillations of the output power with different spectral amplitudes. No clustering or mode grouping effect is observed. Theoretically, we demonstrate a good agreement with a multimode two-color quantum dot laser model.

  15. Quantum Monte Carlo study of long-range transverse-field Ising models on the triangular lattice

    NASA Astrophysics Data System (ADS)

    Humeniuk, Stephan

    2016-03-01

    Motivated by recent experiments with a Penning ion trap quantum simulator, we perform numerically exact Stochastic Series Expansion quantum Monte Carlo simulations of long-range transverse-field Ising models on a triangular lattice for different decay powers α of the interactions. The phase boundary for the ferromagnet is obtained as a function of α . For antiferromagnetic interactions, there is strong indication that the transverse field stabilizes a clock ordered phase with sublattice magnetization (M ,-M/2 ,-M/2 ) with unsaturated M <1 in a process known as "order by disorder" similar to the nearest-neighbor antiferromagnet on the triangular lattice. Connecting the known limiting cases of nearest-neighbor and infinite-range interactions, a semiquantitative phase diagram is obtained. Magnetization curves for the ferromagnet for experimentally relevant system sizes and with open boundary conditions are presented.

  16. Semiclassical approach to model quantum fluids using the statistical associating fluid theory for systems with potentials of variable range

    NASA Astrophysics Data System (ADS)

    Trejos, Víctor M.; Gil-Villegas, Alejandro

    2012-05-01

    Thermodynamic properties of quantum fluids are described using an extended version of the statistical associating fluid theory for potentials of variable range (SAFT-VR) that takes into account quantum corrections to the Helmholtz free energy A, based on the Wentzel-Kramers-Brillouin approximation. We present the theoretical background of this approach (SAFT-VRQ), considering two different cases depending on the continuous or discontinuous nature of the particles pair interaction. For the case of continuous potentials, we demonstrate that the standard Wigner-Kirkwood theory for quantum fluids can be derived from the de Broglie-Bohm formalism for quantum mechanics that can be incorporated within the Barker and Henderson perturbation theory for liquids in a straightforward way. When the particles interact via a discontinuous pair potential, the SAFT-VR method can be combined with the perturbation theory developed by Singh and Sinha [J. Chem. Phys. 67, 3645 (1977); Singh and Sinha J. Chem. Phys. 68, 562 (1978)]. We present an analytical expression for the first-order quantum perturbation term for a square-well potential, and the theory is applied to model thermodynamic properties of hydrogen, deuterium, neon, and helium-4. Vapor-liquid equilibrium, liquid and vapor densities, isochoric and isobaric heat capacities, Joule-Thomson coefficients and inversion curves are predicted accurately with respect to experimental data. We find that quantum corrections are important for the global behavior of properties of these fluids and not only for the low-temperature regime. Predictions obtained for hydrogen compare very favorably with respect to cubic equations of state.

  17. Semiclassical approach to model quantum fluids using the statistical associating fluid theory for systems with potentials of variable range.

    PubMed

    Trejos, Víctor M; Gil-Villegas, Alejandro

    2012-05-14

    Thermodynamic properties of quantum fluids are described using an extended version of the statistical associating fluid theory for potentials of variable range (SAFT-VR) that takes into account quantum corrections to the Helmholtz free energy A, based on the Wentzel-Kramers-Brillouin approximation. We present the theoretical background of this approach (SAFT-VRQ), considering two different cases depending on the continuous or discontinuous nature of the particles pair interaction. For the case of continuous potentials, we demonstrate that the standard Wigner-Kirkwood theory for quantum fluids can be derived from the de Broglie-Bohm formalism for quantum mechanics that can be incorporated within the Barker and Henderson perturbation theory for liquids in a straightforward way. When the particles interact via a discontinuous pair potential, the SAFT-VR method can be combined with the perturbation theory developed by Singh and Sinha [J. Chem. Phys. 67, 3645 (1977); and ibid. 68, 562 (1978)]. We present an analytical expression for the first-order quantum perturbation term for a square-well potential, and the theory is applied to model thermodynamic properties of hydrogen, deuterium, neon, and helium-4. Vapor-liquid equilibrium, liquid and vapor densities, isochoric and isobaric heat capacities, Joule-Thomson coefficients and inversion curves are predicted accurately with respect to experimental data. We find that quantum corrections are important for the global behavior of properties of these fluids and not only for the low-temperature regime. Predictions obtained for hydrogen compare very favorably with respect to cubic equations of state.

  18. Quantum oscillations of the impedance of layered conductors with elastic scattering of electrons by short-range impurity centers

    NASA Astrophysics Data System (ADS)

    Kirichenko, O. V.; Kozlov, I. V.

    2010-07-01

    The propagation of electromagnetic waves in layered conductors in a quantizing magnetic field B is investigated theoretically in the case where elastic scattering by short-range impurity centers is the main relaxation mechanism in the electronic system. Quantum oscillations of the impedance, including at high temperatures, are calculated under the conditions of the anomalous skin effect. The effect of spatial dispersion on the amplitude and phase of the oscillations is analyzed.

  19. Creation of entanglement in a scalable spin quantum computer with long-range dipole-dipole interaction between qubits

    SciTech Connect

    Kamenev, D. I.; Berman, G. P.; Tsifrinovich, V. I.

    2006-06-15

    Creation of entanglement is considered theoretically and numerically in an ensemble of spin chains with dipole-dipole interaction between the spins. The unwanted effect of the long-range dipole interaction is compensated by the optimal choice of the parameters of radio-frequency pulses implementing the protocol. The errors caused by (i) the influence of the environment, (ii) nonselective excitations (iii) influence of different spin chains on each other, (iv) displacements of qubits from their perfect locations, and (v) fluctuations of the external magnetic field are estimated analytically and calculated numerically. For the perfectly entangled state the z component M of the magnetization of the whole system is equal to zero. The errors lead to a finite value of M. If the number of qubits in the system is large, M can be detected experimentally. Using the fact that M depends differently on the parameters of the system for each kind of error, varying these parameters would allow one to experimentally determine the most significant source of errors and to optimize correspondingly the quantum computer design in order to decrease the errors and |M|. Using our approach one can benchmark the quantum computer, decrease the errors, and prepare the quantum computer for implementation of more complex quantum algorithms.

  20. Relativistic klystrons

    SciTech Connect

    Allen, M.A.; Azuma, O.; Callin, R.S.; Deruyter, H.; Eppley, K.R.; Fant, K.S.; Fowkes, W.R.; Herrmannsfeldt, W.B.; Hoag, H.A.; Koontz, R.F.

    1989-03-01

    Experimental work is underway by a SLAC-LLNL-LBL collaboration to investigate the feasibility of using relativistic klystrons as a power source for future high gradient accelerators. Two different relativistic klystron configurations have been built and tested to date: a high grain multicavity klystron at 11.4 GHz and a low gain two cavity subharmonic buncher driven at 5.7 GHz. In both configurations power is extracted at 11.4 GHz. In order to understand the basic physics issues involved in extracting RF from a high power beam, we have used both a single resonant cavity and a multi-cell traveling wave structure for energy extraction. We have learned how to overcome our previously reported problem of high power RF pulse shortening, and have achieved peak RF power levels of 170 MW with the RF pulse of the same duration as the beam current pulse. 6 refs., 3 figs., 3 tabs.

  1. Relativistic harmonic oscillator revisited

    SciTech Connect

    Bars, Itzhak

    2009-02-15

    The familiar Fock space commonly used to describe the relativistic harmonic oscillator, for example, as part of string theory, is insufficient to describe all the states of the relativistic oscillator. We find that there are three different vacua leading to three disconnected Fock sectors, all constructed with the same creation-annihilation operators. These have different spacetime geometric properties as well as different algebraic symmetry properties or different quantum numbers. Two of these Fock spaces include negative norm ghosts (as in string theory), while the third one is completely free of ghosts. We discuss a gauge symmetry in a worldline theory approach that supplies appropriate constraints to remove all the ghosts from all Fock sectors of the single oscillator. The resulting ghost-free quantum spectrum in d+1 dimensions is then classified in unitary representations of the Lorentz group SO(d,1). Moreover, all states of the single oscillator put together make up a single infinite dimensional unitary representation of a hidden global symmetry SU(d,1), whose Casimir eigenvalues are computed. Possible applications of these new results in string theory and other areas of physics and mathematics are briefly mentioned.

  2. RELATIVISTIC HEAVY ION COLLISIONS: EXPERIMENT

    SciTech Connect

    Friedlander, Erwin M.; Heckman, Harry H.

    1982-04-01

    Relativistic heavy ion physics began as a 'no man's land' between particle and nuclear physics, with both sides frowning upon it as 'unclean', because on one hand, hadronic interactions and particle production cloud nuclear structure effects, while on the other, the baryonic environment complicates the interpretation of production experiments. They have attempted to review here the experimental evidence on RHI collisions from the point of view that it represents a new endeavor in the understanding of strong interaction physics. Such an approach appears increasingly justified; first, by the accumulation of data and observations of new features of hadronic interactions that could not have been detected outside a baryonic environment; second, by the maturation of the field owing to the advances made over the past several years in experimental inquiries on particle production by RHI, including pions, kaons, hyperons, and searches for antiprotons; and third, by the steady and progressive increase in the energy and mass ranges of light nuclear beams that have become available to the experiment; indeed the energy range has widened from the {approx} 0.2 to 2 AGeV at the Bevalac to {approx}4 AGeV at Dubna and recently, to the quantum jump in energies to {approx} 1000 equivalent AGeV at the CERN PS-ISR. Accompanying these expansions in the energy frontier are the immediate prospects for very heavy ion beams at the Bevalac up to, and including, 1 AGeV {sup 238}U, thereby extending the 'mass frontier' to its ultimate extent.

  3. Relativistic Astrophysics

    NASA Astrophysics Data System (ADS)

    Jones, Bernard J. T.; Markovic, Dragoljub

    1997-06-01

    Preface; Prologue: Conference overview Bernard Carr; Part I. The Universe At Large and Very Large Redshifts: 2. The size and age of the Universe Gustav A. Tammann; 3. Active galaxies at large redshifts Malcolm S. Longair; 4. Observational cosmology with the cosmic microwave background George F. Smoot; 5. Future prospects in measuring the CMB power spectrum Philip M. Lubin; 6. Inflationary cosmology Michael S. Turner; 7. The signature of the Universe Bernard J. T. Jones; 8. Theory of large-scale structure Sergei F. Shandarin; 9. The origin of matter in the universe Lev A. Kofman; 10. New guises for cold-dark matter suspects Edward W. Kolb; Part II. Physics and Astrophysics Of Relativistic Compact Objects: 11. On the unification of gravitational and inertial forces Donald Lynden-Bell; 12. Internal structure of astrophysical black holes Werner Israel; 13. Black hole entropy: external facade and internal reality Valery Frolov; 14. Accretion disks around black holes Marek A. Abramowicz; 15. Black hole X-ray transients J. Craig Wheeler; 16. X-rays and gamma rays from active galactic nuclei Roland Svensson; 17. Gamma-ray bursts: a challenge to relativistic astrophysics Martin Rees; 18. Probing black holes and other exotic objects with gravitational waves Kip Thorne; Epilogue: the past and future of relativistic astrophysics Igor D. Novikov; I. D. Novikov's scientific papers and books.

  4. Relativistic ionization fronts in gas jets

    NASA Astrophysics Data System (ADS)

    Lemos, Nuno; Dias, J. M.; Gallacher, J. G.; Issac, R. C.; Fonseca, R. A.; Lopes, N. C.; Silva, L. O.; Mendonça, J. T.; Jaroszynski, D. A.

    2006-10-01

    A high-power ultra-short laser pulse propagating through a gas jet, ionizes the gas by tunnelling ionization, creating a relativistic plasma-gas interface. The relativistic ionization front that is created can be used to frequency up-shift electromagnetic radiation either in co-propagation or in counter-propagation configurations. In the counter-propagation configuration, ionization fronts can act as relativistic mirrors for terahertz radiation, leading to relativistic double Doppler frequency up-shift to the visible range. In this work, we identified and explored, the parameters that optimize the key features of relativistic ionization fronts for terahertz radiation reflection. The relativistic ionization front generated by a high power laser (TOPS) propagating in a supersonic gas jet generated by a Laval nozzle has been fully characterized. We have also performed detailed two-dimensional relativistic particle-in-cell simulations with Osiris 2.0 to analyze the generation and propagation of the ionization fronts.

  5. Polyanalytic relativistic second Bargmann transforms

    SciTech Connect

    Mouayn, Zouhaïr

    2015-05-15

    We construct coherent states through special superpositions of eigenstates of the relativistic isotonic oscillator. In each superposition, the coefficients are chosen to be L{sup 2}-eigenfunctions of a σ-weight Maass Laplacian on the Poincaré disk, which are associated with the eigenvalue 4m(σ−1−m), m∈Z{sub +}∩[0,(σ−1)/2]. For each nonzero m, the associated coherent states transform constitutes the m-true-polyanalytic extension of a relativistic version of the second Bargmann transform, whose integral kernel is expressed in terms of a special Appel-Kampé de Fériet’s hypergeometric function. The obtained results could be used to extend the known semi-classical analysis of quantum dynamics of the relativistic isotonic oscillator.

  6. Excited-state quantum phase transitions in many-body systems with infinite-range interaction: Localization, dynamics, and bifurcation

    NASA Astrophysics Data System (ADS)

    Santos, Lea F.; Távora, Marco; Pérez-Bernal, Francisco

    2016-07-01

    Excited-state quantum phase transitions (ESQPTs) are generalizations of quantum phase transitions to excited levels. They are associated with local divergences in the density of states. Here, we investigate how the presence of an ESQPT can be detected from the analysis of the structure of the Hamiltonian matrix, the level of localization of the eigenstates, the onset of bifurcation, and the speed of the system evolution. Our findings are illustrated for a Hamiltonian with infinite-range Ising interaction in a transverse field. This is a version of the Lipkin-Meshkov-Glick (LMG) model and the limiting case of the one-dimensional spin-1/2 system with tunable interactions realized with ion traps. From our studies for the dynamics, we uncover similarities between the LMG and the noninteracting XX models.

  7. Long-Range Order and Low-Energy Spectrum of Diluted 2D Quantum Antiferromagnet

    SciTech Connect

    Chernyshev, A. L.; Chen, Y. C.; Castro Neto, A. H.

    2001-08-06

    The problem of a diluted two-dimensional quantum antiferromagnet on a square lattice is studied using spin-wave theory. The influence of impurities on static and dynamic properties is investigated and a good agreement with experiments and Monte Carlo data is found. The hydrodynamic description of spin waves breaks down at characteristic wavelengths {Lambda}{approx}>exp(const/x) , x being an impurity concentration, while the order parameter is free from anomalies. We argue that this dichotomy originates from strong scattering of the low-energy excitations in two dimensions.

  8. The design of long range quantum electrodynamical forces and torques between macroscopic bodies

    NASA Astrophysics Data System (ADS)

    Iannuzzi, Davide; Lisanti, Mariangela; Munday, Jeremy N.; Capasso, Federico

    2005-09-01

    The interaction between electrically neutral surfaces at sub-micron separation is dominated by the force arising from quantum fluctuations of the electromagnetic field, known as the Casimir force. This effect has been witnessing a renewed interest because of its potential impact in micro- and nanotechnology. Most recent literature has focused on the study of the attraction between bulk-like metallic surfaces in vacuum. Because electromagnetic fluctuations depend on the dielectric function of the surfaces, the use of different materials might reveal new aspects of the Casimir force and suggest novel solutions for the design of micro- and nanofabricated devices. Following this approach, we have measured the Casimir force using Hydrogen Switchable Mirrors—a metallic mirror that switches from highly reflective to transparent when exposed to hydrogen. The comparison of the results obtained in air and in hydrogen sheds light on the relative contribution of visible and infrared wavelengths to the Casimir interaction. We have also studied the dependence of the Casimir force on the metallic film thickness and have shown the effect of the skin-depth. The final section of the paper discusses the torque induced by quantum fluctuations on two birefringent plates and describes an experiment that should allow us to observe this phenomenon.

  9. Quantum dot single molecule tracking reveals a wide range of diffusive motions of membrane transport proteins

    NASA Astrophysics Data System (ADS)

    Crane, Jonathan M.; Haggie, Peter M.; Verkman, A. S.

    2009-02-01

    Single particle tracking (SPT) provides information about the microscopic motions of individual particles in live cells. We applied SPT to study the diffusion of membrane transport proteins in cell plasma membranes in which individual proteins are labeled with quantum dots at engineered extracellular epitopes. Software was created to deduce particle diffusive modes from quantum dot trajectories. SPT of aquaporin (AQP) water channels and cystic fibrosis transmembrane conductance regulator (CFTR) chloride channels revealed several types of diffusion. AQP1 was freely mobile in cell membranes, showing rapid, Brownian-type diffusion. The full-length (M1) isoform of AQP4 also diffused rapidly, though the diffusion of a shorter (M23) isoform of AQP4 was highly restricted due to its supermolecular assembly in raft-like orthogonal arrays. CFTR mobility was also highly restricted, in a spring-like potential, due to its tethering to the actin cytoskeleton through PDZ-domain C-terminus interactions. The biological significance of regulated diffusion of membrane transport proteins is a subject of active investigation.

  10. QUANTUM DOT SINGLE MOLECULE TRACKING REVEALS A WIDE RANGE OF DIFFUSIVE MOTIONS OF MEMBRANE TRANSPORT PROTEINS.

    PubMed

    Crane, Jonathan M; Haggie, Peter M; Verkman, A S

    2009-03-01

    Single particle tracking (SPT) provides information about the microscopic motions of individual particles in live cells. We applied SPT to study the diffusion of membrane transport proteins in cell plasma membranes in which individual proteins are labeled with quantum dots at engineered extracellular epitopes. Software was created to deduce particle diffusive modes from quantum dot trajectories. SPT of aquaporin (AQP) water channels and cystic fibrosis transmembrane conductance regulator (CFTR) chloride channels revealed several types of diffusion. AQP1 was freely mobile in cell membranes, showing rapid, Brownian-type diffusion. The full-length (M1) isoform of AQP4 also diffused rapidly, though the diffusion of a shorter (M23) isoform of AQP4 was highly restricted due to its supermolecular assembly in raft-like orthogonal arrays. CFTR mobility was also highly restricted, in a spring-like potential, due to its tethering to the actin cytoskeleton through PDZ-domain C-terminus interactions. The biological significance of regulated diffusion of membrane transport proteins is a subject of active investigation.

  11. Stable mean-field solution of a short-range interacting SO(3) quantum Heisenberg spin glass.

    PubMed

    da Conceição, C M S; Marino, E C

    2008-07-18

    We present a mean-field solution for a quantum, short-range interacting, disordered, SO(3) Heisenberg spin model, in which the Gaussian distribution of couplings is centered in an antiferromagnetic (AF) coupling J[over ]>0, and which, for weak disorder, can be treated as a perturbation of the pure AF Heisenberg system. The phase diagram contains, apart from a Néel phase at T=0, spin-glass and paramagnetic phases whose thermodynamic stability is demonstrated by an analysis of the Hessian matrix of the free-energy. The magnetic susceptibilities exhibit the typical cusp of a spin-glass transition.

  12. Matrix Continued Fraction Solution to the Relativistic Spin-0 Feshbach-Villars Equations

    NASA Astrophysics Data System (ADS)

    Brown, N. C.; Papp, Z.; Woodhouse, R.

    2016-03-01

    The Feshbach-Villars equations, like the Klein-Gordon equation, are relativistic quantum mechanical equations for spin-0 particles.We write the Feshbach-Villars equations into an integral equation form and solve them by applying the Coulomb-Sturmian potential separable expansion method. We consider boundstate problems in a Coulomb plus short range potential. The corresponding Feshbach-Villars CoulombGreen's operator is represented by a matrix continued fraction.

  13. Quantum spin dynamics with pairwise-tunable, long-range interactions.

    PubMed

    Hung, C-L; González-Tudela, Alejandro; Cirac, J Ignacio; Kimble, H J

    2016-08-23

    We present a platform for the simulation of quantum magnetism with full control of interactions between pairs of spins at arbitrary distances in 1D and 2D lattices. In our scheme, two internal atomic states represent a pseudospin for atoms trapped within a photonic crystal waveguide (PCW). With the atomic transition frequency aligned inside a band gap of the PCW, virtual photons mediate coherent spin-spin interactions between lattice sites. To obtain full control of interaction coefficients at arbitrary atom-atom separations, ground-state energy shifts are introduced as a function of distance across the PCW. In conjunction with auxiliary pump fields, spin-exchange versus atom-atom separation can be engineered with arbitrary magnitude and phase, and arranged to introduce nontrivial Berry phases in the spin lattice, thus opening new avenues for realizing topological spin models. We illustrate the broad applicability of our scheme by explicit construction for several well-known spin models. PMID:27496329

  14. Formation of long range ordered arrangement of quantum dots with the help of lateral centripetal flow

    NASA Astrophysics Data System (ADS)

    Fu, Yunzhi; Li, Jinru; Du, Yu kou; Jiang, Long

    2006-02-01

    A simple "chimney" method was used to eliminate the voids in an arrangement of quantum dots sized 2 nm on a solid substrate, which resulted in a large well ordered superlattice of area in the order more than 1 μm 2. Based on the principle of speeding up the interparticle interaction of nanoparticles to overcome the particle-substrate one, a lateral centripetal force originated from a glass tube acting as a chimney in a simple evaporation device is imposed. This method allows the packing process to be controlled in a mechanical force field, that is, with the same nanogold dispersion different patterns on a substrate—from separate dots to an ordered compact monolayer or even a multilayer structure—could be easily obtained.

  15. Quantum spin dynamics with pairwise-tunable, long-range interactions

    NASA Astrophysics Data System (ADS)

    Hung, C.-L.; González-Tudela, Alejandro; Cirac, J. Ignacio; Kimble, H. J.

    2016-08-01

    We present a platform for the simulation of quantum magnetism with full control of interactions between pairs of spins at arbitrary distances in 1D and 2D lattices. In our scheme, two internal atomic states represent a pseudospin for atoms trapped within a photonic crystal waveguide (PCW). With the atomic transition frequency aligned inside a band gap of the PCW, virtual photons mediate coherent spin-spin interactions between lattice sites. To obtain full control of interaction coefficients at arbitrary atom-atom separations, ground-state energy shifts are introduced as a function of distance across the PCW. In conjunction with auxiliary pump fields, spin-exchange versus atom-atom separation can be engineered with arbitrary magnitude and phase, and arranged to introduce nontrivial Berry phases in the spin lattice, thus opening new avenues for realizing topological spin models. We illustrate the broad applicability of our scheme by explicit construction for several well-known spin models.

  16. Quantum spin dynamics with pairwise-tunable, long-range interactions

    PubMed Central

    Hung, C.-L.; González-Tudela, Alejandro; Cirac, J. Ignacio; Kimble, H. J.

    2016-01-01

    We present a platform for the simulation of quantum magnetism with full control of interactions between pairs of spins at arbitrary distances in 1D and 2D lattices. In our scheme, two internal atomic states represent a pseudospin for atoms trapped within a photonic crystal waveguide (PCW). With the atomic transition frequency aligned inside a band gap of the PCW, virtual photons mediate coherent spin–spin interactions between lattice sites. To obtain full control of interaction coefficients at arbitrary atom–atom separations, ground-state energy shifts are introduced as a function of distance across the PCW. In conjunction with auxiliary pump fields, spin-exchange versus atom–atom separation can be engineered with arbitrary magnitude and phase, and arranged to introduce nontrivial Berry phases in the spin lattice, thus opening new avenues for realizing topological spin models. We illustrate the broad applicability of our scheme by explicit construction for several well-known spin models. PMID:27496329

  17. Quantum tasks in Minkowski space

    NASA Astrophysics Data System (ADS)

    Kent, Adrian

    2012-11-01

    The fundamental properties of quantum information and its applications to computing and cryptography have been greatly illuminated by considering information-theoretic tasks that are provably possible or impossible within non-relativistic quantum mechanics. I describe here a general framework for defining tasks within (special) relativistic quantum theory and illustrate it with examples from relativistic quantum cryptography and relativistic distributed quantum computation. The framework gives a unified description of all tasks previously considered and also defines a large class of new questions about the properties of quantum information in relation to Minkowski causality. It offers a way of exploring interesting new fundamental tasks and applications, and also highlights the scope for a more systematic understanding of the fundamental information-theoretic properties of relativistic quantum theory.

  18. Single electron relativistic clock interferometer

    NASA Astrophysics Data System (ADS)

    Bushev, P. A.; Cole, J. H.; Sholokhov, D.; Kukharchyk, N.; Zych, M.

    2016-09-01

    Although time is one of the fundamental notions in physics, it does not have a unique description. In quantum theory time is a parameter ordering the succession of the probability amplitudes of a quantum system, while according to relativity theory each system experiences in general a different proper time, depending on the system's world line, due to time dilation. It is therefore of fundamental interest to test the notion of time in the regime where both quantum and relativistic effects play a role, for example, when different amplitudes of a single quantum clock experience different magnitudes of time dilation. Here we propose a realization of such an experiment with a single electron in a Penning trap. The clock can be implemented in the electronic spin precession and its time dilation then depends on the radial (cyclotron) state of the electron. We show that coherent manipulation and detection of the electron can be achieved already with present day technology. A single electron in a Penning trap is a technologically ready platform where the notion of time can be probed in a hitherto untested regime, where it requires a relativistic as well as quantum description.

  19. Monolithically integrated quantum dot optical modulator with Semiconductor optical amplifier for short-range optical communications

    NASA Astrophysics Data System (ADS)

    Yamamoto, Naokatsu; Akahane, Kouichi; Umezawa, Toshimasa; Kawanishi, Tetsuya

    2015-04-01

    A monolithically integrated quantum dot (QD) optical gain modulator (OGM) with a QD semiconductor optical amplifier (SOA) was successfully developed. Broadband QD optical gain material was used to achieve Gbps-order high-speed optical data transmission, and an optical gain change as high as approximately 6-7 dB was obtained with a low OGM voltage of 2.0 V. Loss of optical power due to insertion of the device was also effectively compensated for by the SOA section. Furthermore, it was confirmed that the QD-OGM/SOA device helped achieve 6.0-Gbps error-free optical data transmission over a 2.0-km-long photonic crystal fiber. We also successfully demonstrated generation of Gbps-order, high-speed, and error-free optical signals in the >5.5-THz broadband optical frequency bandwidth larger than the C-band. These results suggest that the developed monolithically integrated QD-OGM/SOA device will be an advantageous and compact means of increasing the usable optical frequency channels for short-reach communications.

  20. Relativistic Continuum Shell Model

    NASA Astrophysics Data System (ADS)

    Grineviciute, Janina; Halderson, Dean

    2011-04-01

    The R-matrix formalism of Lane and Thomas has been extended to the relativistic case so that the many-coupled channels problem may be solved for systems in which binary breakup channels satisfy a relative Dirac equation. The formalism was previously applied to the relativistic impulse approximation RIA and now we applied it to Quantum Hadrodynamics QHD in the continuum Tamm-Dancoff approximation TDA with the classical meson fields replaced by one-meson exchange potentials. None of the published QHD parameters provide a decent fit to the 15 N + p elastic cross section. The deficiency is also evident in inability of the QHD parameters with the one meson exchange potentials to reproduce the QHD single particle energies. Results with alternate parameters sets are presented. A. M. Lane and R. G. Thomas, R-Matrix Theory of Nuclear Reactions, Reviews of Modern Physics, 30 (1958) 257

  1. Relativistic corrections to the Moyal-Weyl spacetime

    SciTech Connect

    Much, A.

    2015-02-15

    We use the framework of quantum field theory to obtain by deformation the Moyal-Weyl spacetime. This idea is extracted from recent progress in deformation theory concerning the emergence of the quantum plane of the Landau-quantization. The quantum field theoretical emerging spacetime is not equal to the standard Moyal-Weyl plane, but terms resembling relativistic corrections occur.

  2. Relativistic fluid dynamics. Proceedings.

    NASA Astrophysics Data System (ADS)

    Anile, A. M.; Choquet-Bruhat, Y.

    Contents: 1. Covariant theory of conductivity in ideal fluid or solid media (B. Carter). 2. Hamiltonian techniques for relativistic fluid dynamics and stability theory (D. D. Holm). 3. Covariant fluid mechanics and thermodynamics: an introduction (W. Israel). 4. Relativistic plasmas (H. Weitzner). 5. An improved relativistic warm plasma model (A. M. Anile, S. Pennisi). 6. Relativistic extended thermodynamics II (I. Müller). 7. Relativistic extended thermodynamics: general assumptions and mathematical procedure (T. Ruggeri). 8. Relativistic hydrodynamics and heavy ion reactions (D. Strottman). 9. Some problems in relativistic hydrodynamics (C. G. van Weert).

  3. Spin dynamics in relativistic light-matter interaction

    NASA Astrophysics Data System (ADS)

    Bauke, Heiko; Ahrens, Sven; Keitel, Christoph H.; Grobe, Rainer

    2015-05-01

    Various spin effects are expected to become observable in light-matter interaction at relativistic intensities. Relativistic quantum mechanics equipped with a suitable relativistic spin operator forms the theoretical foundation for describing these effects. Various proposals for relativistic spin operators have been offered by different authors, which are presented in a unified way. As a result of the operators' mathematical properties only the Foldy-Wouthuysen operator and the Pryce operator qualify as possible proper relativistic spin operators. The ground states of highly charged hydrogen-like ions can be utilized to identify a legitimate relativistic spin operator experimentally. Subsequently, the Foldy-Wouthuysen spin operator is employed to study electron-spin precession in high-intensity standing light waves with elliptical polarization. For a correct theoretical description of the predicted electron-spin precession relativistic effects due to the spin angular momentum of the electromagnetic wave has to be taken into account even in the limit of low intensities.

  4. Noninvariance of space- and time-scale ranges under a Lorentz Transformation and the implications for the study of relativistic interactions.

    PubMed

    Vay, J-L

    2007-03-30

    We present an analysis which shows that the ranges of space and time scales spanned by a system are not invariant under Lorentz transformation. This implies the existence of a frame of reference which minimizes an aggregate measure of the range of space and time scales. Such a frame is derived, for example, for the following cases: free electron laser, laser-plasma accelerator, and particle beams interacting with electron clouds. The implications for experimental, theoretical, and numerical studies are discussed. The most immediate relevance is the reduction by orders of magnitude in computer simulation run times for such systems. PMID:17501172

  5. Noninvariance of space- and time-scale ranges under a Lorentz Transformation and the implications for the study of relativistic interactions.

    PubMed

    Vay, J-L

    2007-03-30

    We present an analysis which shows that the ranges of space and time scales spanned by a system are not invariant under Lorentz transformation. This implies the existence of a frame of reference which minimizes an aggregate measure of the range of space and time scales. Such a frame is derived, for example, for the following cases: free electron laser, laser-plasma accelerator, and particle beams interacting with electron clouds. The implications for experimental, theoretical, and numerical studies are discussed. The most immediate relevance is the reduction by orders of magnitude in computer simulation run times for such systems.

  6. {sup 63}Cu and {sup 197}Au nuclear quadrupole moments from four-component relativistic density-functional calculations using correct long-range exchange

    SciTech Connect

    Thierfelder, Christian; Schwerdtfeger, Peter; Saue, Trond

    2007-09-15

    The electric field gradient in late transition metal compounds is incorrectly determined by most density functionals. We show that the coupling of short-range density functional based with long-range wave function based methods using a reparametrization of the Coulomb-attenuated Becke three-parameter Lee-Yang-Parr approximation gives reliable results for the electric field gradients of copper and gold for a series of compounds. This results in nuclear quadrupole moments of -0.208 b for {sup 63}Cu and +0.526 b for {sup 197}Au in good agreement with experimental values of -0.220(15) and +0.547(16)b, respectively.

  7. Noninvariance of Space and Time Scale Ranges under a Lorentz Transformation and the Implications for the Numerical Study of Relativistic Systems

    SciTech Connect

    Vay, J.-L.; Vay, J.-L.

    2007-11-12

    We present an analysis which shows that the ranges of space and time scales spanned by a system are not invariant under the Lorentz transformation. This implies the existence of a frame of reference which minimizes an aggregate measure of the range of space and time scales. Such a frame is derived for example cases: free electron laser, laser-plasma accelerator, and particle beam interacting with electron clouds. Implications for experimental, theoretical and numerical studies are discussed. The most immediate relevance is the reduction by orders of magnitude in computer simulation run times for such systems.

  8. Surface-emitting terahertz quantum cascade lasers with continuous-wave power in the tens of milliwatt range

    SciTech Connect

    Xu, Gangyi; Li, Lianhe; Giles Davies, A.; Linfield, Edmund H.; Isac, Nathalie; Halioua, Yacine; Colombelli, Raffaele

    2014-03-03

    We demonstrate efficient surface-emitting terahertz frequency quantum cascade lasers with continuous wave output powers of 20–25 mW at 15 K and maximum operating temperatures of 80–85 K. The devices employ a resonant-phonon depopulation active region design with injector, and surface emission is realized using resonators based on graded photonic heterostructures (GPHs). GPHs can be regarded as energy wells for photons and have recently been implemented through grading the period of the photonic structure. In this paper, we show that it is possible to keep the period constant and grade instead the lateral metal coverage across the GPH. This strategy ensures spectrally single-mode operation across the whole laser dynamic range and represents an additional degree of freedom in the design of confining potentials for photons.

  9. Opto-electronic device for frequency standard generation and terahertz-range optical demodulation based on quantum interference

    DOEpatents

    Georgiades, N.P.; Polzik, E.S.; Kimble, H.J.

    1999-02-02

    An opto-electronic system and technique for comparing laser frequencies with large frequency separations, establishing new frequency standards, and achieving phase-sensitive detection at ultra high frequencies are disclosed. Light responsive materials with multiple energy levels suitable for multi-photon excitation are preferably used for nonlinear mixing via quantum interference of different excitation paths affecting a common energy level. Demodulation of a carrier with a demodulation frequency up to 100`s THZ can be achieved for frequency comparison and phase-sensitive detection. A large number of materials can be used to cover a wide spectral range including the ultra violet, visible and near infrared regions. In particular, absolute frequency measurement in a spectrum from 1.25 {micro}m to 1.66 {micro}m for fiber optics can be accomplished with a nearly continuous frequency coverage. 7 figs.

  10. Opto-electronic device for frequency standard generation and terahertz-range optical demodulation based on quantum interference

    DOEpatents

    Georgiades, Nikos P.; Polzik, Eugene S.; Kimble, H. Jeff

    1999-02-02

    An opto-electronic system and technique for comparing laser frequencies with large frequency separations, establishing new frequency standards, and achieving phase-sensitive detection at ultra high frequencies. Light responsive materials with multiple energy levels suitable for multi-photon excitation are preferably used for nonlinear mixing via quantum interference of different excitation paths affecting a common energy level. Demodulation of a carrier with a demodulation frequency up to 100's THZ can be achieved for frequency comparison and phase-sensitive detection. A large number of materials can be used to cover a wide spectral range including the ultra violet, visible and near infrared regions. In particular, absolute frequency measurement in a spectrum from 1.25 .mu.m to 1.66 .mu.m for fiber optics can be accomplished with a nearly continuous frequency coverage.

  11. Superoscillations underlying remote state preparation for relativistic fields

    NASA Astrophysics Data System (ADS)

    Ber, Ran; Kenneth, Oded; Reznik, Benni

    2015-05-01

    We present a physical (gedanken) implementation of a generalized remote state preparation of relativistic quantum field states for an arbitrary set of observers. The prepared states are created in regions that are outside the future light cone of the generating region. The mechanism, which is based on utilizing the vacuum state of a relativistic quantum field as a resource, sheds light on the well known Reeh-Schlieder theorem, indicating its strong connection with the mathematical phenomenon of superoscillations.

  12. Duskside relativistic electron precipitation

    NASA Astrophysics Data System (ADS)

    Lorentzen, Kirsten Ruth

    1999-10-01

    On August 20, 1996, a balloon-borne X-ray pinhole camera and a high resolution germanium X-ray spectrometer observed an intense X-ray event near Kiruna, Sweden, at 1835 MLT, on an L-shell of 5.8. This X-ray event consisted of seven bursts spaced 100-200 seconds apart, with smaller 10-20 second variations observed within individual bursts. The energy spectra of these bursts show the presence of X-rays with energies greater than 1 MeV, which are best accounted for by atmospheric bremsstrahlung from mono-energetic 1.7 MeV precipitating electrons. The X-ray imager observed no significant motion or small-scale spatial structure in the event, implying that the bursts were temporal in nature. Ultra- violet images from the Polar satellite and energetic particle data from the Los Alamos geosynchronous satellites show a small magnetospheric substorm onset about 24 minutes before the start of the relativistic precipitation event. Since the balloon was south of the auroral oval and there was no associated increase in relativistic electron flux at geosynchronous altitude, the event must be the result of some mechanism selectively precipitating ambient relativistic electrons from the radiation belts. The balloon X-ray observations are analyzed in a magnetospheric context, in order to determine which of several mechanisms for selective precipitation of relativistic electrons can account for the event. Resonance with electromagnetic ion cyclotron mode waves on the equator is the most likely candidate. The drift of substorm-injected warm protons is calculated using input from the geosynchronous satellites. Wave growth in the model is driven by temperature anisotropies in the warm proton population. A numerical solution of the wave dispersion relation shows that electromagnetic ion cyclotron waves can be excited in high-density duskside regions such as the plasmasphere or detached plasma regions. These waves can selectively precipitate relativistic electrons of energy 1.7 MeV in

  13. Practical Relativistic Bit Commitment.

    PubMed

    Lunghi, T; Kaniewski, J; Bussières, F; Houlmann, R; Tomamichel, M; Wehner, S; Zbinden, H

    2015-07-17

    Bit commitment is a fundamental cryptographic primitive in which Alice wishes to commit a secret bit to Bob. Perfectly secure bit commitment between two mistrustful parties is impossible through an asynchronous exchange of quantum information. Perfect security is, however, possible when Alice and Bob each split into several agents exchanging classical information at times and locations suitably chosen to satisfy specific relativistic constraints. In this Letter we first revisit a previously proposed scheme [C. Crépeau et al., Lect. Notes Comput. Sci. 7073, 407 (2011)] that realizes bit commitment using only classical communication. We prove that the protocol is secure against quantum adversaries for a duration limited by the light-speed communication time between the locations of the agents. We then propose a novel multiround scheme based on finite-field arithmetic that extends the commitment time beyond this limit, and we prove its security against classical attacks. Finally, we present an implementation of these protocols using dedicated hardware and we demonstrate a 2 ms-long bit commitment over a distance of 131 km. By positioning the agents on antipodal points on the surface of Earth, the commitment time could possibly be extended to 212 ms.

  14. Refining a relativistic, hydrodynamic solver: Admitting ultra-relativistic flows

    NASA Astrophysics Data System (ADS)

    Bernstein, J. P.; Hughes, P. A.

    2009-09-01

    We have undertaken the simulation of hydrodynamic flows with bulk Lorentz factors in the range 102-106. We discuss the application of an existing relativistic, hydrodynamic primitive variable recovery algorithm to a study of pulsar winds, and, in particular, the refinement made to admit such ultra-relativistic flows. We show that an iterative quartic root finder breaks down for Lorentz factors above 102 and employ an analytic root finder as a solution. We find that the former, which is known to be robust for Lorentz factors up to at least 50, offers a 24% speed advantage. We demonstrate the existence of a simple diagnostic allowing for a hybrid primitives recovery algorithm that includes an automatic, real-time toggle between the iterative and analytical methods. We further determine the accuracy of the iterative and hybrid algorithms for a comprehensive selection of input parameters and demonstrate the latter’s capability to elucidate the internal structure of ultra-relativistic plasmas. In particular, we discuss simulations showing that the interaction of a light, ultra-relativistic pulsar wind with a slow, dense ambient medium can give rise to asymmetry reminiscent of the Guitar nebula leading to the formation of a relativistic backflow harboring a series of internal shockwaves. The shockwaves provide thermalized energy that is available for the continued inflation of the PWN bubble. In turn, the bubble enhances the asymmetry, thereby providing positive feedback to the backflow.

  15. The quantum measurement of time

    NASA Technical Reports Server (NTRS)

    Shepard, Scott R.

    1994-01-01

    Traditionally, in non-relativistic Quantum Mechanics, time is considered to be a parameter, rather than an observable quantity like space. In relativistic Quantum Field Theory, space and time are treated equally by reducing space to also be a parameter. Herein, after a brief review of other measurements, we describe a third possibility, which is to treat time as a directly observable quantity.

  16. Relativistic hydrodynamics on graphic cards

    NASA Astrophysics Data System (ADS)

    Gerhard, Jochen; Lindenstruth, Volker; Bleicher, Marcus

    2013-02-01

    We show how to accelerate relativistic hydrodynamics simulations using graphic cards (graphic processing units, GPUs). These improvements are of highest relevance e.g. to the field of high-energetic nucleus-nucleus collisions at RHIC and LHC where (ideal and dissipative) relativistic hydrodynamics is used to calculate the evolution of hot and dense QCD matter. The results reported here are based on the Sharp And Smooth Transport Algorithm (SHASTA), which is employed in many hydrodynamical models and hybrid simulation packages, e.g. the Ultrarelativistic Quantum Molecular Dynamics model (UrQMD). We have redesigned the SHASTA using the OpenCL computing framework to work on accelerators like graphic processing units (GPUs) as well as on multi-core processors. With the redesign of the algorithm the hydrodynamic calculations have been accelerated by a factor 160 allowing for event-by-event calculations and better statistics in hybrid calculations.

  17. 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.

  18. Relativistic electron beam generator

    DOEpatents

    Mooney, L.J.; Hyatt, H.M.

    1975-11-11

    A relativistic electron beam generator for laser media excitation is described. The device employs a diode type relativistic electron beam source having a cathode shape which provides a rectangular output beam with uniform current density.

  19. Lasing of multiperiod quantum-cascade lasers in the spectral range of (5.6–5.8)-μm under current pumping

    SciTech Connect

    Egorov, A. Yu. Babichev, A. V.; Karachinsky, L. Ya.; Novikov, I. I.; Nikitina, E. V.; Tchernycheva, M.; Sofronov, A. N.; Firsov, D. A.; Vorobjev, L. E.; Pikhtin, N. A.; Tarasov, I. S.

    2015-11-15

    The lasing of multiperiod quantum-cascade lasers in the spectral range of (5.6–5.8)-μm under current pumping are demonstrated. The quantum-cascade laser heterostructure is grown by molecular-beam epitaxy technique. Despite the relatively short laser cavity length and high level of external loss the laser shows the lasing in the temperature range of 80–220 K. The threshold current density below 4 kA/cm{sup 2} at 220 K with the characteristic temperature T{sub 0} = 123 K was demonstrated.

  20. PHYSICAL BASIS OF QUANTUM ELECTRONICS: Stimulated scattering of electromagnetic waves by a relativistic electron beam in a three-dimensional geometry

    NASA Astrophysics Data System (ADS)

    Karimov, A. R.; Poponin, V. P.; Rukhadze, Anri A.; Shcheglov, V. A.

    1999-05-01

    The properties of stimulated coherent scattering of an electromagnetic wave by a relativistic electron beam were studied in the framework of a three-wave approximation for a noncollinear geometry, when the incident and the scattered waves can propagate at arbitrary angles relative to the electron beam direction. The dispersion equation was obtained, making it possible to investigate the modes of collective (Raman) and single-particle (Compton) scattering from a unified viewpoint and to include the effect of an external longitudinal magnetic field on the electron motion in the field of a combination wave. Formulas were obtained for the amplitude increments of the scattered and the combination waves for those scattering modes, which can be used to make estimates when selecting the optimal scheme of a free-electron laser with a noncollinear scattering geometry.

  1. Selective removal of atherosclerotic plaque with a quantum cascade laser in the 5.7 µm wavelength range

    NASA Astrophysics Data System (ADS)

    Hashimura, Keisuke; Ishii, Katsunori; Awazu, Kunio

    2015-11-01

    Atherosclerotic plaques consist mainly of cholesteryl esters, and the C=O stretching vibration mode of cholesteryl esters strongly absorbs radiation at a wavelength of 5.75 µm. For clinical application of less-invasive laser angioplasty with 5.75 µm, a compact laser is required. Quantum cascade lasers (QCLs) are semiconductor lasers that can emit radiation in the mid-IR range. In this study, the potential of the QCL for less-invasive laser angioplasty was evaluated. At the average power density of 180 W/cm2, the atherosclerotic aorta was ablated for the irradiation time of 1 s or more, whereas the normal aorta was ablated for more than 10 s. This demonstrates that selective ablation of the atherosclerotic aorta was achieved. However, strong coagulation and carbonization were observed. For reducing thermal effects, improving the pulse structure is required. In conclusion, the QCL achieved the selective ablation of the atherosclerotic lesions, which indicates the potential of the QCL.

  2. Relativistic Iron Line Fits

    NASA Astrophysics Data System (ADS)

    Fink, M.; Dauser, T.; Beuchert, T.; Jeffreson, S.; Tawabutr, J.; Wilms, J.; García, J.; Walton, D. J.

    2016-08-01

    The 6.4 keV Iron reflection line possesses strong diagnostic potential for AGN-systems. In the rare case of unobscured AGN, this line receives a contribution from the very center of the accretion flow close to the event horizon that is subject to strong relativistic effects. The shape of this line distortion can be used infer important parameters of the central accretion region, especially the black hole spin parameter a* and the accretion disk inclination i. We analyze several (nine?) bare AGN spectra from the sample of Walton et al. 2012 using high resolution spectra from the XMM and NuStar archives. The relativistic reflection is modeled using the RELXILL code (Dauser 20XX). The newest iteration of the RELXILL model also supports a lamp post geometry for the irradiation of the accretion disk. By combining these detailed models with the wide spectral range of NuStar and XMM/NuStar joint observations we can put tight constraints on the aforementioned parameters and we can constrain the height of the source h in a possible lamp post geometry.

  3. Photon detectors with high quantum efficiency at NUV range using a confinement of wavelength-shifted signals and optical couplers

    NASA Astrophysics Data System (ADS)

    Takahashi, Y.; Hadaway, J.; Pakhomov, A.; Takizawa, Y.

    Near-UV wavelengths 300 - 400 nm have been in a death-valley for photon detectors due to very low quantum efficiencies QE in this range Conventional bi-alkali photocathodes of PMTs do not have QE better than 20-26 Much better photo-cathodes like GaAsP GaN and similar give better efficiencies but only at wavelengths 400nm and are severely plagued by very short lifetimes Avalanche Photo-diodes perform better at low temperatures but no better than 35 QE in the NUV region Silicon Photo-multipliers at Geiger mode SiPM with micro-pixels have high QEs 90 like CCD and CMOS as bare silicon but are severely plagued by very poor geometrical fill-factors 30 and their overallQMis limited to no better than 20 at NUV regime An optical interference-filter works as a half-mirror passing more than 90 of NUV lights 300-400 nm and reflect more than 90 of longer wavelength lights 400 nm UV photons after converted into blue-green lights by wavelength-shifter are reflected back and confined without much loss back into space A specific dichroic interference mirror with WLS was made by RIKEN Japan H Shimizu Y Takahashi Y Takizawa Patent pending 2000-399940 for this optical principle It also allows a better use of limited photo-sensitive micro-cells of SiPM overcoming the past serious problem of its very poor fill-factor As a result Half-mirror SiPM yields high final efficiency for NUV photons This new detector TRAPPER with optical couplers for SiPM or by GaAsP PMTs could be used for photon-hungry space experiments at NUV range TRAPPER

  4. Isospin flip as a relativistic effect: NN interactions

    NASA Technical Reports Server (NTRS)

    Buck, W. W.

    1993-01-01

    Results are presented of an analytic relativistic calculation of a OBE nucleon-nucleon (NN) interaction employing the Gross equation. The calculation consists of a non-relativistic reduction that keeps the negative energy states. The result is compared to purely non-relativistic OBEP results and the relativistic effects are separated out. One finds that the resulting relativistic effects are expressable as a power series in (tau(sub 1))(tau(sub 2)) that agrees, qualitatively, with NN scattering. Upon G-parity transforming this NN potential, one obtains, qualitatively, a short range NN spectroscopy in which the S-states are the lowest states.

  5. Crystallization and collapse in relativistically degenerate matter

    SciTech Connect

    Akbari-Moghanjoughi, M.

    2013-04-15

    In this paper, it is shown that a mass density limit exists beyond which the relativistically degenerate matter would crystallize. The mass density limit, found here, is quite analogous to the mass limit predicted by Chandrasekhar for a type of compact stars called white dwarfs (M{sub Ch} Asymptotically-Equal-To 1.43 Solar Mass). In this study, the old problem of white dwarf core collapse, which has been previously investigated by Chandrasekhar using hydrostatic stability criteria, is revisited in the framework of the quantum hydrodynamics model by inspection of the charge screening at atomic scales in the relativistic degeneracy plasma regime taking into account the relativistic Fermi-Dirac statistics and electron interaction features such as the quantum statistical pressure, Coulomb attraction, electron exchange-correlation, and quantum recoil effects. It is revealed that the existence of ion correlation and crystallization of matter in the relativistically degenerate plasma puts a critical mass density limit on white dwarf core region. It is shown that a white dwarf star with a core mass density beyond this critical limit can undergo the spontaneous core collapse (SCC). The SCC phenomenon, which is dominantly caused by the electron quantum recoil effect (interference and localization of the electron wave function), leads to a new exotic state of matter. In such exotic state, the relativistic electron degeneracy can lead the white dwarf crystallized core to undergo the nuclear fusion and an ultimate supernova by means of the volume reduction (due to the enhanced compressibility) and huge energy release (due to the increase in cohesive energy), under the stars huge inward gravitational pressure. Moreover, it is found that the SCC phenomenon is significantly affected by the core composition (it is more probable for heavier plasmas). The critical mass density found here is consistent with the values calculated for core density of typical white dwarf stars.

  6. 2 μm wavelength range InP-based type-II quantum well photodiodes heterogeneously integrated on silicon photonic integrated circuits.

    PubMed

    Wang, Ruijun; Sprengel, Stephan; Muneeb, Muhammad; Boehm, Gerhard; Baets, Roel; Amann, Markus-Christian; Roelkens, Gunther

    2015-10-01

    The heterogeneous integration of InP-based type-II quantum well photodiodes on silicon photonic integrated circuits for the 2 µm wavelength range is presented. A responsivity of 1.2 A/W at a wavelength of 2.32 µm and 0.6 A/W at 2.4 µm wavelength is demonstrated. The photodiodes have a dark current of 12 nA at -0.5 V at room temperature. The absorbing active region of the integrated photodiodes consists of six periods of a "W"-shaped quantum well, also allowing for laser integration on the same platform.

  7. Ro-vibrational quenching of CO (v = 1) by He impact in a broad range of temperatures: A benchmark study using mixed quantum/classical inelastic scattering theory.

    PubMed

    Semenov, Alexander; Ivanov, Mikhail; Babikov, Dmitri

    2013-08-21

    The mixed quantum/classical approach is applied to the problem of ro-vibrational energy transfer in the inelastic collisions of CO(v = 1) with He atom, in order to predict the quenching rate coefficient in a broad range of temperatures 5 < T < 2500 K. Scattering calculations are done in two different ways: direct calculations of quenching cross sections and, alternatively, calculations of the excitation cross sections plus microscopic reversibility. In addition, a symmetrized average-velocity method of Billing is tried. Combination of these methods allows reproducing experiment in a broad range of temperatures. Excellent agreement with experiment is obtained at 400 < T < 2500 K (within 10%), good agreement in the range 100 < T < 400 K (within 25%), and semi-quantitative agreement at 40 < T < 100 K(within a factor of 2). This study provides a stringent test of the mixed quantum/classical theory, because the vibrational quantum in CO molecule is rather large and the quencher is very light (He atom). For heavier quenchers and closer to dissociation limit of the molecule, the mixed quantum/classical theory is expected to work even better.

  8. Exact quantisation of the relativistic Hopfield model

    NASA Astrophysics Data System (ADS)

    Belgiorno, F.; Cacciatori, S. L.; Dalla Piazza, F.; Doronzo, M.

    2016-11-01

    We investigate the quantisation in the Heisenberg representation of a relativistically covariant version of the Hopfield model for dielectric media, which entails the interaction of the quantum electromagnetic field with the matter dipole fields, represented by a mesoscopic polarisation field. A full quantisation of the model is provided in a covariant gauge, with the aim of maintaining explicit relativistic covariance. Breaking of the Lorentz invariance due to the intrinsic presence in the model of a preferred reference frame is also taken into account. Relativistic covariance forces us to deal with the unphysical (scalar and longitudinal) components of the fields, furthermore it introduces, in a more tricky form, the well-known dipole ghost of standard QED in a covariant gauge. In order to correctly dispose of this contribution, we implement a generalised Lautrup trick. Furthermore, causality and the relation of the model with the Wightman axioms are also discussed.

  9. Quantum simulation of the Dirac equation.

    PubMed

    Gerritsma, R; Kirchmair, G; Zähringer, F; Solano, E; Blatt, R; Roos, C F

    2010-01-01

    The Dirac equation successfully merges quantum mechanics with special relativity. It provides a natural description of the electron spin, predicts the existence of antimatter and is able to reproduce accurately the spectrum of the hydrogen atom. The realm of the Dirac equation-relativistic quantum mechanics-is considered to be the natural transition to quantum field theory. However, the Dirac equation also predicts some peculiar effects, such as Klein's paradox and 'Zitterbewegung', an unexpected quivering motion of a free relativistic quantum particle. These and other predicted phenomena are key fundamental examples for understanding relativistic quantum effects, but are difficult to observe in real particles. In recent years, there has been increased interest in simulations of relativistic quantum effects using different physical set-ups, in which parameter tunability allows access to different physical regimes. Here we perform a proof-of-principle quantum simulation of the one-dimensional Dirac equation using a single trapped ion set to behave as a free relativistic quantum particle. We measure the particle position as a function of time and study Zitterbewegung for different initial superpositions of positive- and negative-energy spinor states, as well as the crossover from relativistic to non-relativistic dynamics. The high level of control of trapped-ion experimental parameters makes it possible to simulate textbook examples of relativistic quantum physics. PMID:20054392

  10. Lorentzian quantum reality: postulates and toy models.

    PubMed

    Kent, Adrian

    2015-08-01

    We describe postulates for a novel realist version of relativistic quantum theory or quantum field theory in Minkowski space and other background space-times, and illustrate their application with toy models. PMID:26124245

  11. Relativistic Linear Restoring Force

    ERIC Educational Resources Information Center

    Clark, D.; Franklin, J.; Mann, N.

    2012-01-01

    We consider two different forms for a relativistic version of a linear restoring force. The pair comes from taking Hooke's law to be the force appearing on the right-hand side of the relativistic expressions: d"p"/d"t" or d"p"/d["tau"]. Either formulation recovers Hooke's law in the non-relativistic limit. In addition to these two forces, we…

  12. Relativistic Guiding Center Equations

    SciTech Connect

    White, R. B.; Gobbin, M.

    2014-10-01

    In toroidal fusion devices it is relatively easy that electrons achieve relativistic velocities, so to simulate runaway electrons and other high energy phenomena a nonrelativistic guiding center formalism is not sufficient. Relativistic guiding center equations including flute mode time dependent field perturbations are derived. The same variables as used in a previous nonrelativistic guiding center code are adopted, so that a straightforward modifications of those equations can produce a relativistic version.

  13. Relativistic effects in Lyman-α forest

    NASA Astrophysics Data System (ADS)

    Iršič, Vid; Di Dio, Enea; Viel, Matteo

    2016-02-01

    We present the calculation of the Lyman-alpha (Lyman-α) transmitted flux fluctuations with full relativistic corrections to the first order. Even though several studies exist on relativistic effects in galaxy clustering, this is the first study to extend the formalism to a different tracer of underlying matter at unique redshift range (z=2-5). Furthermore, we show a comprehensive application of our calculations to the Quasar-Lyman-α cross-correlation function. Our results indicate that the signal of relativistic effects are sizeable at Baryonic Acoustic Oscillation (BAO) scale mainly due to the large differences in density bias factors of our tracers. We construct an observable, the anti-symmetric part of the cross-correlation function, that is dominated by the relativistic signal and offers a new way to measure the relativistic terms at relatively small scales. The analysis shows that relativistic effects are important when considering cross-correlations between tracers with very different biases, and should be included in the data analysis of the current and future surveys. Moreover, the idea presented in this paper is highly complementary to other techniques and observables trying to isolate the effect of the relativistic corrections and thus test the validity of the theory of gravity beyond the Newtonian regime.

  14. Coupled modes in magnetized dense plasma with relativistic-degenerate electrons

    SciTech Connect

    Khan, S. A.

    2012-01-15

    Low frequency electrostatic and electromagnetic waves are investigated in ultra-dense quantum magnetoplasma with relativistic-degenerate electron and non-degenerate ion fluids. The dispersion relation is derived for mobile as well as immobile ions by employing hydrodynamic equations for such plasma under the influence of electromagnetic forces and pressure gradient of relativistic-degenerate Fermi gas of electrons. The result shows the coexistence of shear Alfven and ion modes with relativistically modified dispersive properties. The relevance of results to the dense degenerate plasmas of astrophysical origin (for instance, white dwarf stars) is pointed out with brief discussion on ultra-relativistic and non-relativistic limits.

  15. Relativistic Runaway Electrons

    NASA Astrophysics Data System (ADS)

    Breizman, Boris

    2014-10-01

    This talk covers recent developments in the theory of runaway electrons in a tokamak with an emphasis on highly relativistic electrons produced via the avalanche mechanism. The rapidly growing population of runaway electrons can quickly replace a large part of the initial current carried by the bulk plasma electrons. The magnetic energy associated with this current is typically much greater than the particle kinetic energy. The current of a highly relativistic runaway beam is insensitive to the particle energy, which separates the description of the runaway current evolution from the description of the runaway energy spectrum. A strongly anisotropic distribution of fast electrons is generally prone to high-frequency kinetic instabilities that may cause beneficial enhancement of runaway energy losses. The relevant instabilities are in the frequency range of whistler waves and electron plasma waves. The instability thresholds reported in earlier work have been revised considerably to reflect strong dependence of collisional damping on the wave frequency and the role of plasma non-uniformity, including radial trapping of the excited waves in the plasma. The talk also includes a discussion of enhanced scattering of the runaways as well as the combined effect of enhanced scattering and synchrotron radiation. A noteworthy feature of the avalanche-produced runaway current is a self-sustained regime of marginal criticality: the inductive electric field has to be close to its critical value (representing avalanche threshold) at every location where the runaway current density is finite, and the current density should vanish at any point where the electric field drops below its critical value. This nonlinear Ohm's law enables complete description of the evolving current profile. Work supported by the U.S. Department of Energy Contract No. DEFG02-04ER54742 and by ITER contract ITER-CT-12-4300000273. The views and opinions expressed herein do not necessarily reflect those of

  16. Generalized charge-screening in relativistic Thomas-Fermi model

    NASA Astrophysics Data System (ADS)

    Akbari-Moghanjoughi, M.

    2014-10-01

    In this paper, we study the charge shielding within the relativistic Thomas-Fermi model for a wide range of electron number-densities and the atomic-number of screened ions. A generalized energy-density relation is obtained using the force-balance equation and taking into account the Chandrasekhar's relativistic electron degeneracy pressure. By numerically solving a second-order nonlinear differential equation, the Thomas-Fermi screening length is investigated, and the results are compared for three distinct regimes of the solid-density, warm-dense-matter, and white-dwarfs (WDs). It is revealed that our nonlinear screening theory is compatible with the exponentially decaying Thomas-Fermi-type shielding predicted by the linear response theory. Moreover, the variation of relative Thomas-Fermi screening length shows that extremely dense quantum electron fluids are relatively poor charge shielders. Calculation of the total number of screening electrons around a nucleus shows that there is a position of maximum number of screening localized electrons around the screened nucleus, which moves closer to the point-like nucleus by increase in the plasma number density but is unaffected due to increase in the atomic-number value. It is discovered that the total number of screening electrons, ( N s ∝ r T F 3 / r d 3 where rTF and rd are the Thomas-Fermi and interparticle distance, respectively) has a distinct limit for extremely dense plasmas such as WD-cores and neutron star crusts, which is unique for all given values of the atomic-number. This is equal to saying that in an ultrarelativistic degeneracy limit of electron-ion plasma, the screening length couples with the system dimensionality and the plasma becomes spherically self-similar. Current analysis can provide useful information on the effects of relativistic correction to the charge screening for a wide range of plasma density, such as the inertial-confined plasmas and compact stellar objects.

  17. Use of the Sturm expansion of the Coulomb Green function in quantum electrodynamics: photon scattering by a bound electron

    SciTech Connect

    Manakov, N.L.; Nekipelov, A.A.; Fai-brevenshtei-breven, A.G.

    1987-04-01

    The method of the Sturm expansion of the relativistic Coulomb Green function G(E) is extended to the continuum range chemically bondEchemically bond>mc/sup 2/. The cross section for elastic and inelastic scattering of a ..gamma.. quantum by a hydrogenlike ion is calculated. Asymmetry effects in the polarization dependence of the scattering cross section are considered.

  18. Carrier transfer and recombination dynamics of a long-lived and visible range emission from multi-stacked GaN/AlGaN quantum dots

    SciTech Connect

    Kim, Je-Hyung; Kwon, Bong-Joon; Cho, Yong-Hoon; Huault, Thomas; Leroux, Mathieu; Brault, Julien

    2010-08-09

    We have investigated the optical properties of multi-stacked GaN/AlGaN self-assembled quantum dots (QDs) grown by molecular beam epitaxy. The QDs that emit visible light have a broad spectral range without incorporation of indium alloy because of the quantum-confined Stark effect. We found differences in the structural and optical properties between the layers of multi-stacked QDs. The carriers are more effectively transferred from the AlGaN barrier to the low energy side of the GaN QD emission than to the high energy side. We also observed long-lived carrier recombination dynamics for the visible range emission from QDs.

  19. Relativistic decay widths of autoionization processes: The relativistic FanoADC-Stieltjes method

    SciTech Connect

    Fasshauer, Elke; Kolorenč, Přemysl; Pernpointner, Markus

    2015-04-14

    Electronic decay processes of ionized systems are, for example, the Auger decay or the Interatomic/ Intermolecular Coulombic Decay. In both processes, an energetically low lying vacancy is filled by an electron of an energetically higher lying orbital and a secondary electron is instantaneously emitted to the continuum. Whether or not such a process occurs depends both on the energetic accessibility and the corresponding lifetime compared to the lifetime of competing decay mechanisms. We present a realization of the non-relativistically established FanoADC-Stieltjes method for the description of autoionization decay widths including relativistic effects. This procedure, being based on the Algebraic Diagrammatic Construction (ADC), was adapted to the relativistic framework and implemented into the relativistic quantum chemistry program package Dirac. It is, in contrast to other existing relativistic atomic codes, not limited to the description of autoionization lifetimes in spherically symmetric systems, but is instead also applicable to molecules and clusters. We employ this method to the Auger processes following the Kr3d{sup −1}, Xe4d{sup −1}, and Rn5d{sup −1} ionization. Based on the results, we show a pronounced influence of mainly scalar-relativistic effects on the decay widths of autoionization processes.

  20. Using Quantum Mechanics to Facilitate the Introduction of a Broad Range of Chemical Concepts to First-Year Undergraduate Students

    ERIC Educational Resources Information Center

    deSouza, Romualdo T.; Iyengar, Srinivasan S.

    2013-01-01

    A first-year undergraduate course that introduces students to chemistry through a conceptually detailed description of quantum mechanics is outlined. Quantization as arising from the confinement of a particle is presented and these ideas are used to introduce the reasons behind resonance, molecular orbital theory, degeneracy of electronic states,…

  1. Quantum algorithms for quantum field theories.

    PubMed

    Jordan, Stephen P; Lee, Keith S M; Preskill, John

    2012-06-01

    Quantum field theory reconciles quantum mechanics and special relativity, and plays a central role in many areas of physics. We developed a quantum algorithm to compute relativistic scattering probabilities in a massive quantum field theory with quartic self-interactions (φ(4) theory) in spacetime of four and fewer dimensions. Its run time is polynomial in the number of particles, their energy, and the desired precision, and applies at both weak and strong coupling. In the strong-coupling and high-precision regimes, our quantum algorithm achieves exponential speedup over the fastest known classical algorithm. PMID:22654052

  2. Quantum algorithms for quantum field theories.

    PubMed

    Jordan, Stephen P; Lee, Keith S M; Preskill, John

    2012-06-01

    Quantum field theory reconciles quantum mechanics and special relativity, and plays a central role in many areas of physics. We developed a quantum algorithm to compute relativistic scattering probabilities in a massive quantum field theory with quartic self-interactions (φ(4) theory) in spacetime of four and fewer dimensions. Its run time is polynomial in the number of particles, their energy, and the desired precision, and applies at both weak and strong coupling. In the strong-coupling and high-precision regimes, our quantum algorithm achieves exponential speedup over the fastest known classical algorithm.

  3. Relativistic diffusive motion in thermal electromagnetic fields

    NASA Astrophysics Data System (ADS)

    Haba, Z.

    2013-04-01

    We discuss relativistic dynamics in a random electromagnetic field which can be considered as a high temperature limit of the quantum electromagnetic field in a heat bath (cavity) moving with a uniform velocity w. We derive a diffusion approximation for the particle’s dynamics generalizing the diffusion of Schay and Dudley. It is shown that the Jüttner distribution is the equilibrium state of the diffusion.

  4. Relativistic thermodynamics with an invariant energy scale

    SciTech Connect

    Das, Sudipta; Ghosh, Subir; Roychowdhury, Dibakar

    2009-12-15

    A particular framework for quantum gravity is the doubly special relativity (DSR) formalism that introduces a new observer independent scale, the Planck energy. Our aim in this paper is to study the effects of this energy upper bound in relativistic thermodynamics. We have explicitly computed the modified equation of state for an ideal fluid in the DSR framework. In deriving our result we exploited the scheme of treating DSR as a nonlinear representation of the Lorentz group in special relativity.

  5. Weyl, Dirac and Maxwell Quantum Cellular Automata

    NASA Astrophysics Data System (ADS)

    Bisio, Alessandro; D'Ariano, Giacomo Mauro; Perinotti, Paolo; Tosini, Alessandro

    2015-10-01

    Recent advances on quantum foundations achieved the derivation of free quantum field theory from general principles, without referring to mechanical notions and relativistic invariance. From the aforementioned principles a quantum cellular automata (QCA) theory follows, whose relativistic limit of small wave-vector provides the free dynamics of quantum field theory. The QCA theory can be regarded as an extended quantum field theory that describes in a unified way all scales ranging from an hypothetical discrete Planck scale up to the usual Fermi scale. The present paper reviews the automaton theory for the Weyl field, and the composite automata for Dirac and Maxwell fields. We then give a simple analysis of the dynamics in the momentum space in terms of a dispersive differential equation for narrowband wave-packets. We then review the phenomenology of the free-field automaton and consider possible visible effects arising from the discreteness of the framework. We conclude introducing the consequences of the automaton dispersion relation, leading to a deformed Lorentz covariance and to possible effects on the thermodynamics of ideal gases.

  6. Noise in gallium nitride-based quantum well structures used for nanometer devices in the frequency range 1 Hz--3 Mhz and temperature range 77K--324K

    NASA Astrophysics Data System (ADS)

    Duran, Rolando Silvano

    Electronic noise has been investigated in AlxGa1-x N/GaN Modulation-Doped Field Effect Transistors (MODFETs) of submicron dimensions, grown for us by MBE (Molecular Beam Epitaxy) techniques at Virginia Commonwealth University by Dr. H. Morkoc and coworkers. Some 20 devices were grown on a GaN substrate, four of which have leads bonded to source (S), drain (D), and gate (G) pads, respectively. Conduction takes place in the quasi-2D layer of the junction (xy plane) which is perpendicular to the quantum well (z-direction) of average triangular width ˜3 nm. A non-doped intrinsic buffer layer of ˜5 nm separates the Si-doped donors in the AlxGa1-xN layer from the 2D-transistor plane, which affords a very high electron mobility, thus enabling high-speed devices. Since all contacts (S, D, and G) must reach through the AlxGa1-xN layer to connect internally to the 2D plane, parallel conduction through this layer is a feature of all modulation-doped devices. While the shunting effect may account for no more than a few percent of the current IDS, it is responsible for most excess noise, over and above thermal noise of the device. The excess noise has been analyzed as a sum of Lorentzian spectra and 1/f noise. The Lorentzian noise has been ascribed to trapping of the carriers in the AlxGa1-xN layer. A detailed, multitrapping generation-recombination noise theory is presented, which shows that an exponential relationship exists for the time constants obtained from the spectral components as a function of 1/kT. The trap depths have been obtained from Arrhenius plots of log (tauT2) vs. 1000/T. Comparison with previous noise results for GaAs devices shows that: (a) many more trapping levels are present in these nitride-based devices; (b) the traps are deeper (farther below the conduction band) than for GaAs. Furthermore, the magnitude of the noise is strongly dependent on the level of depletion of the AlxGa1-xN donor layer, which can be altered by a negative or positive gate bias

  7. The Los Alamos suite of relativistic atomic physics codes

    SciTech Connect

    Fontes, C. J.; Zhang, H. L.; Jr, J. Abdallah; Clark, R. E. H.; Kilcrease, D. P.; Colgan, J.; Cunningham, R. T.; Hakel, P.; Magee, N. H.; Sherrill, M. E.

    2015-05-28

    The Los Alamos SuitE of Relativistic (LASER) atomic physics codes is a robust, mature platform that has been used to model highly charged ions in a variety of ways. The suite includes capabilities for calculating data related to fundamental atomic structure, as well as the processes of photoexcitation, electron-impact excitation and ionization, photoionization and autoionization within a consistent framework. These data can be of a basic nature, such as cross sections and collision strengths, which are useful in making predictions that can be compared with experiments to test fundamental theories of highly charged ions, such as quantum electrodynamics. The suite can also be used to generate detailed models of energy levels and rate coefficients, and to apply them in the collisional-radiative modeling of plasmas over a wide range of conditions. Such modeling is useful, for example, in the interpretation of spectra generated by a variety of plasmas. In this work, we provide a brief overview of the capabilities within the Los Alamos relativistic suite along with some examples of its application to the modeling of highly charged ions.

  8. The Los Alamos suite of relativistic atomic physics codes

    DOE PAGES

    Fontes, C. J.; Zhang, H. L.; Jr, J. Abdallah; Clark, R. E. H.; Kilcrease, D. P.; Colgan, J.; Cunningham, R. T.; Hakel, P.; Magee, N. H.; Sherrill, M. E.

    2015-05-28

    The Los Alamos SuitE of Relativistic (LASER) atomic physics codes is a robust, mature platform that has been used to model highly charged ions in a variety of ways. The suite includes capabilities for calculating data related to fundamental atomic structure, as well as the processes of photoexcitation, electron-impact excitation and ionization, photoionization and autoionization within a consistent framework. These data can be of a basic nature, such as cross sections and collision strengths, which are useful in making predictions that can be compared with experiments to test fundamental theories of highly charged ions, such as quantum electrodynamics. The suitemore » can also be used to generate detailed models of energy levels and rate coefficients, and to apply them in the collisional-radiative modeling of plasmas over a wide range of conditions. Such modeling is useful, for example, in the interpretation of spectra generated by a variety of plasmas. In this work, we provide a brief overview of the capabilities within the Los Alamos relativistic suite along with some examples of its application to the modeling of highly charged ions.« less

  9. Relativistic Definition of Spin Operators

    NASA Astrophysics Data System (ADS)

    Ryder, Lewis H.

    2002-12-01

    Some years ago Mashhoon [1] made the highly interesting suggestion that there existed a coupling of spin with rotations, just as there exists such a coupling with orbital angular momentum, as seen in the Sagnac effect, for example. Spin being essentially a quantum phenomenon, the obvious place to look for this was by studying the Dirac equation, and Hehl and Ni, in such an investigation [2], indeed found a coupling term of just the type Mashhoon had envisaged. Part of their procedure, however, was to take the nonrelativistic limit, and this was done by performing appropriate Foldy-Wouthuysen (FW) transformations. In the nonrelativistic limit, it is well-known that the spin operators for Dirac particles are in essence the Pauli matrices; but it is also well-known, and indeed was part of the motivation for Foldy and Wouthuysen's paper, that for fully-fledged Dirac particles the (4×4 generalisation of the) Pauli matrices do not yield satisfactory spin operators, since spin defined in this way would not be conserved. The question therefore presented itself: is there a relativistic spin operator for Dirac particles, such that in the relativistic, as well as the nonrelativistic, régime a Mashhoon spin-rotation coupling exists?...

  10. 24-Hour Relativistic Bit Commitment

    NASA Astrophysics Data System (ADS)

    Verbanis, Ephanielle; Martin, Anthony; Houlmann, Raphaël; Boso, Gianluca; Bussières, Félix; Zbinden, Hugo

    2016-09-01

    Bit commitment is a fundamental cryptographic primitive in which a party wishes to commit a secret bit to another party. Perfect security between mistrustful parties is unfortunately impossible to achieve through the asynchronous exchange of classical and quantum messages. Perfect security can nonetheless be achieved if each party splits into two agents exchanging classical information at times and locations satisfying strict relativistic constraints. A relativistic multiround protocol to achieve this was previously proposed and used to implement a 2-millisecond commitment time. Much longer durations were initially thought to be insecure, but recent theoretical progress showed that this is not so. In this Letter, we report on the implementation of a 24-hour bit commitment solely based on timed high-speed optical communication and fast data processing, with all agents located within the city of Geneva. This duration is more than 6 orders of magnitude longer than before, and we argue that it could be extended to one year and allow much more flexibility on the locations of the agents. Our implementation offers a practical and viable solution for use in applications such as digital signatures, secure voting and honesty-preserving auctions.

  11. A relativistic toy model for Unruh black holes

    NASA Astrophysics Data System (ADS)

    Carbonaro, P.

    2014-08-01

    We consider the wave propagation in terms of acoustic geometry in a quantum relativistic system. This reduces, in the hydrodynamic limit, to the equations which govern the motion of a relativistic Fermi-degenerate gas in one space dimension. The derivation of an acoustic metric for one-dimensional (1D) systems is in general plagued with the impossibility of defining a conformal factor. Here we show that, although the system is intrinsically one-dimensional, the Unruh procedure continues to work because of the particular structure symmetry of the model. By analyzing the dispersion relation, attention is also paid to the quantum effects on the wave propagation.

  12. Exact Relativistic Newtonian Representation of Gravitational static Spacetime Geometries

    NASA Astrophysics Data System (ADS)

    Ghosh, Shubhrangshu; Sarkar, Tamal; Bhadra, Arunava

    2016-09-01

    We construct a self-consistent relativistic Newtonian analogue corresponding to gravitational static spherical symmetric spacetime geometries, starting directly from a generalized scalar relativistic gravitational action in a Newtonian framework, which gives geodesic equations of motion identical to those of the parent metric. Consequently, the derived velocity-dependent relativistic scalar potential, which is a relativistic generalization of the Newtonian gravitational potential, exactly reproduces the relativistic gravitational features corresponding to any static spherical symmetric spacetime geometry in its entirety, including all the experimentally tested gravitational effects in the weak field up to the present. This relativistic analogous potential is expected to be quite useful in studying a wide range of astrophysical phenomena, especially in strong field gravity.

  13. Relativistic Tennis Using Flying Mirror

    SciTech Connect

    Pirozhkov, A. S.; Kando, M.; Ma, J.; Fukuda, Y.; Chen, L.-M.; Daito, I.; Ogura, K.; Homma, T.; Hayashi, Y.; Kotaki, H.; Sagisaka, A.; Mori, M.; Koga, J. K.; Kawachi, T.; Daido, H.; Kimura, T.; Kato, Y.; Tajima, T.; Esirkepov, T. Zh.; Bulanov, S. V.

    2008-06-24

    Upon reflection from a relativistic mirror, the electromagnetic pulse frequency is upshifted and the duration is shortened by the factor proportional to the relativistic gamma-factor squared due to the double Doppler effect. We present the results of the proof-of-principle experiment for frequency upshifting of the laser pulse reflected from the relativistic 'flying mirror', which is a wake wave near the breaking threshold created by a strong driver pulse propagating in underdense plasma. Experimentally, the wake wave is created by a 2 TW, 76 fs Ti:S laser pulse from the JLITE-X laser system in helium plasma with the electron density of {approx_equal}4-6x10{sup 19} cm{sup -3}. The reflected signal is observed with a grazing-incidence spectrograph in 24 shots. The wavelength of the reflected radiation ranges from 7 to 14 nm, the corresponding frequency upshifting factors are {approx}55-115, and the gamma-factors are y = 4-6. The reflected signal contains at least 3x10{sup 7} photons/sr. This effect can be used to generate coherent high-frequency ultrashort pulses that inherit temporal shape and polarization from the original (low-frequency) ones. Apart from this, the reflected radiation contains important information about the wake wave itself, e.g. location, size, phase velocity, etc.

  14. Relativistic Tennis Using Flying Mirror

    NASA Astrophysics Data System (ADS)

    Pirozhkov, A. S.; Kando, M.; Esirkepov, T. Zh.; Ma, J.; Fukuda, Y.; Chen, L.-M.; Daito, I.; Ogura, K.; Homma, T.; Hayashi, Y.; Kotaki, H.; Sagisaka, A.; Mori, M.; Koga, J. K.; Kawachi, T.; Daido, H.; Bulanov, S. V.; Kimura, T.; Kato, Y.; Tajima, T.

    2008-06-01

    Upon reflection from a relativistic mirror, the electromagnetic pulse frequency is upshifted and the duration is shortened by the factor proportional to the relativistic gamma-factor squared due to the double Doppler effect. We present the results of the proof-of-principle experiment for frequency upshifting of the laser pulse reflected from the relativistic "flying mirror", which is a wake wave near the breaking threshold created by a strong driver pulse propagating in underdense plasma. Experimentally, the wake wave is created by a 2 TW, 76 fs Ti:S laser pulse from the JLITE-X laser system in helium plasma with the electron density of ≈4-6×1019 cm-3. The reflected signal is observed with a grazing-incidence spectrograph in 24 shots. The wavelength of the reflected radiation ranges from 7 to 14 nm, the corresponding frequency upshifting factors are ˜55-115, and the gamma-factors are y = 4-6. The reflected signal contains at least 3×107 photons/sr. This effect can be used to generate coherent high-frequency ultrashort pulses that inherit temporal shape and polarization from the original (low-frequency) ones. Apart from this, the reflected radiation contains important information about the wake wave itself, e.g. location, size, phase velocity, etc.

  15. Relativistic effects on x-ray structure factors

    NASA Astrophysics Data System (ADS)

    Batke, Kilian; Eickerling, Georg

    2016-04-01

    Today, combined experimental and theoretical charge density studies based on quantum chemical calculations and x-ray diffraction experiments allow for the investigation of the topology of the electron density at subatomic resolution. When studying compounds containing transition metal elements, relativistic effects need to be adequately taken into account not only in quantum chemical calculations of the total electron density ρ ({r}), but also for the atomic scattering factors employed to extract ρ ({r}) from experimental x-ray diffraction data. In the present study, we investigate the magnitude of relativistic effects on x-ray structure factors and for this purpose {F}({{r}}*) have been calculated for the model systems M(C2H2) (M = Ni, Pd, Pt) from four-component molecular wave functions. Relativistic effects are then discussed by a comparison to structure factors obtained from a non-relativistic reference and different quasi-relativistic approximations. We show, that the overall effects of relativity on the structure factors on average amount to 0.81%, 1.51% and 2.78% for the three model systems under investigation, but that for individual reflections or reflection series the effects can be orders of magnitude larger. Employing the quasi-relativistic Douglas-Kroll-Hess second order or the zeroth order regular approximation Hamiltonian takes these effects into account to a large extend, reducing the differences between the (quasi-)relativistic and the non-relativistic result by one order of magnitude. In order to further determine the experimental significance of the results, the magnitude of the relativistic effects is compared to the changes of the model structure factor data when charge transfer and chemical bonding is taken into account by a multipolar expansion of {F}({{r}}*).

  16. Distinct optical properties of relativistically degenerate matter

    SciTech Connect

    Akbari-Moghanjoughi, M.

    2014-06-15

    In this paper, we use the collisional quantum magnetohydrodynamic (CQMHD) model to derive the transverse dielectric function of a relativistically degenerate electron fluid and investigate various optical parameters, such as the complex refractive index, the reflection and absorption coefficients, the skin-depth and optical conductivity. In this model we take into accounts effects of many parameters such as the atomic-number of the constituent ions, the electron exchange, electron diffraction effect and the electron-ion collisions. Study of the optical parameters in the solid-density, the warm-dense-matter, the big-planetary core, and the compact star number-density regimes reveals that there are distinct differences between optical characteristics of the latter and the former cases due to the fundamental effects of the relativistic degeneracy and other quantum mechanisms. It is found that in the relativistic degeneracy plasma regime, such as found in white-dwarfs and neutron star crusts, matter possess a much sharper and well-defined step-like reflection edge beyond the x-ray electromagnetic spectrum, including some part of gamma-ray frequencies. It is also remarked that the magnetic field intensity only significantly affects the plasma reflectivity in the lower number-density regime, rather than the high density limit. Current investigation confirms the profound effect of relativistic degeneracy on optical characteristics of matter and can provide an important plasma diagnostic tool for studying the physical processes within the wide scope of quantum plasma regimes be it the solid-density, inertial-confined, or astrophysical compact stars.

  17. The effect of finite-range THz radiation on the electronic transport in a quantum well wire

    NASA Astrophysics Data System (ADS)

    Asgharpoor, Bahareh; Hessami Pilehrood, Saeid

    2016-09-01

    A quantum well wire system with lateral parabolic confinement, partly irradiated by intense terahertz laser radiation, is considered. Using the exact electronic states of the system in the presence of the laser field, the transmission probabilities for the sideband components of the electronic states, through the irradiated region, are obtained. Then by considering the scattering of the emerging electronic states by a δ-function scatterer in a formalism based on the Lippmann-Schwinger approach, the contribution of the sideband components in the transmission coefficients and the conductance of the wire are determined. Results indicate the possibility to control the transmission pattern across the wire.

  18. Quantum-cascade lasers as local oscillators for heterodyne spectrometers in the spectral range around 4.745 THz

    NASA Astrophysics Data System (ADS)

    Schrottke, L.; Wienold, M.; Sharma, R.; Lü, X.; Biermann, K.; Hey, R.; Tahraoui, A.; Richter, H.; Hübers, H.-W.; Grahn, H. T.

    2013-03-01

    Local oscillators in terahertz heterodyne spectrometers have to be operated in continuous-wave mode at precisely defined target frequencies. In particular, for advanced airborne instruments, several specifications such as operating temperature and cooling requirements are necessary to be considered. We have developed a quantum-cascade laser (QCL) applicable as a local oscillator for heterodyne spectroscopy of the OI line at 4.745 THz, which is of particular interest for astronomy. We demonstrate a distributed-feedback QCL operating in continuous-wave mode up to about 60 K, which can be tuned precisely to the target frequency when operated in a mechanical cooler.

  19. Consistent relativistic treatment of the structure of the deuteron and its electromagnetic interactions

    SciTech Connect

    Franz Gross

    1996-02-01

    Relativistic calculations of deuteron static properties, the triton binding energy, and deuteron form factors are presented. The results show that the covariant formalism is capable of replacing nonrelativistic quantum mechanics, at least for the description of two and three body systems, and that some significant new insights emerge when the dynamics is described relativistically.

  20. One-Dimensional Relativistic Dissipative System with Constant Force and its Quantization

    NASA Astrophysics Data System (ADS)

    López, G.; López, X. E.; Hernández, H.

    2006-04-01

    For a relativistic particle under a constant force and a linear velocity dissipation force, a constant of motion is found. Problems are shown for getting the Hamiltonian of this system. Thus, the quantization of this system is carried out through the constant of motion and using the quantization on the velocity variable. The dissipative relativistic quantum bouncer is outlined within this quantization approach.

  1. Relativistic dynamics of quasistable states. II. Differentiable representations of the causal Poincare semigroup

    SciTech Connect

    Wickramasekara, S.

    2009-07-15

    We construct two rigged Hilbert spaces that furnish differentiable representations of the causal Poincare semigroup. These rigged Hilbert spaces provide the mathematical foundation for a theory of relativistic quasistable states that synthesizes the S-matrix description of resonance scattering with the Bakamjian-Thomas construction for interacting relativistic quantum systems.

  2. Relativistic Gravity Research

    NASA Astrophysics Data System (ADS)

    Ehlers, Jürgen; Schäfer, Gerhard

    17 readable articles give a thorough and self-contained overview of recent developments in relativistic gravity research. The subjects covered are: gravitational lensing, the general relativistic n-body problem, observable effects in the solar system, gravitational waves and their interferometric detection, very-long-baseline interferometry, international atomic time, lunar laserranging measurements, measurement of the gravitomagnetic field of the Earth, fermion and boson stars and black holes with hair, rapidly rotating neutron stars, matter wave interferometry, and the laboratory test of Newton's law of gravity. Any scientist interested in experimentally or observatio- nally oriented relativistic gravity will read the book with profit. In addition, it is perfectly suited as a complementary text for courses on general relativity and relativistic astrophysics.

  3. Relativistic spherical plasma waves

    NASA Astrophysics Data System (ADS)

    Bulanov, S. S.; Maksimchuk, A.; Schroeder, C. B.; Zhidkov, A. G.; Esarey, E.; Leemans, W. P.

    2012-02-01

    Tightly focused laser pulses that diverge or converge in underdense plasma can generate wake waves, having local structures that are spherical waves. Here we study theoretically and numerically relativistic spherical wake waves and their properties, including wave breaking.

  4. Exact Relativistic `Antigravity' Propulsion

    NASA Astrophysics Data System (ADS)

    Felber, Franklin S.

    2006-01-01

    The Schwarzschild solution is used to find the exact relativistic motion of a payload in the gravitational field of a mass moving with constant velocity. At radial approach or recession speeds faster than 3-1/2 times the speed of light, even a small mass gravitationally repels a payload. At relativistic speeds, a suitable mass can quickly propel a heavy payload from rest nearly to the speed of light with negligible stresses on the payload.

  5. Relativistic electron acceleration by oblique whistler waves

    SciTech Connect

    Yoon, Peter H.; Pandey, Vinay S.; Lee, Dong-Hun

    2013-11-15

    Test-particle simulations of electrons interacting with finite-amplitude, obliquely propagating whistler waves are carried out in order to investigate the acceleration of relativistic electrons by these waves. According to the present findings, an efficient acceleration of relativistic electrons requires a narrow range of oblique propagation angles, close to the whistler resonance cone angle, when the wave amplitude is held constant at relatively low value. For a constant wave propagation angle, it is found that a range of oblique whistler wave amplitudes permits the acceleration of relativistic electrons to O(MeV) energies. An initial distribution of test electrons is shown to form a power-law distribution when plotted in energy space. It is also found that the acceleration is largely uniform in electron pitch-angle space.

  6. Relativistic effects in chemistry

    SciTech Connect

    Yatsimirskii, K.B.

    1995-11-01

    Relativistic effects become apparent when the velocity of the electron is arbitrarily close to the speed of light (137 au) without actually attaining it (in heavy atoms of elements at the end of Mendeleev`s Periodic Table). At the orbital level, the relativistic effect is apparent in the radial contraction of penetrating s and p shells, expansion of nonpenetrating d and f shells, and the spin-orbit splitting of p-,d-, and f-shells. The appearance of a relativistic effect is indicated in the variation in the electronic configurations of the atoms in the Periodic Table, the appearance of new types of closed electron shells (6s{sub 1/2}{sup 2}, 6p{sub 1/2}{sup 2}, 7s{sub 1/2}{sup 2}, 5d{sub 3/2}{sup 4}), the stabilization of unstable oxidation states of heavy elements, the characteristic variation in the ionization enthalpies of heavy atoms, their electron affinity, hydration energies, redox potentials, and optical electronegativities. In the spectra of coordination compounds, a relativistic effect is observed when comparing the position of the charge transfer bands in analogous compounds, the parameters characterizing the ligand field strength (10Dq), the interatomic distances and angles in compounds of heavy elements. A relativistic effect is also apparent in the ability of heavy metals to form clusters and superclusters. Relativistic corrections also affect other properties of heavy metal compounds (force constants, dipole moments, biological activity, etc.).

  7. Relativistic Landau models and generation of fuzzy spheres

    NASA Astrophysics Data System (ADS)

    Hasebe, Kazuki

    2016-07-01

    Noncommutative geometry naturally emerges in low energy physics of Landau models as a consequence of level projection. In this work, we proactively utilize the level projection as an effective tool to generate fuzzy geometry. The level projection is specifically applied to the relativistic Landau models. In the first half of the paper, a detail analysis of the relativistic Landau problems on a sphere is presented, where a concise expression of the Dirac-Landau operator eigenstates is obtained based on algebraic methods. We establish SU(2) “gauge” transformation between the relativistic Landau model and the Pauli-Schrödinger nonrelativistic quantum mechanics. After the SU(2) transformation, the Dirac operator and the angular momentum operators are found to satisfy the SO(3, 1) algebra. In the second half, the fuzzy geometries generated from the relativistic Landau levels are elucidated, where unique properties of the relativistic fuzzy geometries are clarified. We consider mass deformation of the relativistic Landau models and demonstrate its geometrical effects to fuzzy geometry. Super fuzzy geometry is also constructed from a supersymmetric quantum mechanics as the square of the Dirac-Landau operator. Finally, we apply the level projection method to real graphene system to generate valley fuzzy spheres.

  8. Relativistic nuclear many-body theory

    SciTech Connect

    Serot, B.D. ); Walecka, J.D. . Continuous Electron Beam Accelerator Facility)

    1991-09-11

    Nonrelativistic models of nuclear systems have provided important insight into nuclear physics. In future experiments, nuclear systems will be examined under extreme conditions of density and temperature, and their response will be probed at momentum and energy transfers larger than the nucleon mass. It is therefore essential to develop reliable models that go beyond the traditional nonrelativistic many-body framework. General properties of physics, such as quantum mechanics, Lorentz covariance, and microscopic causality, motivate the use of quantum field theories to describe the interacting, relativistic, nuclear many-body system. Renormalizable models based on hadronic degrees of freedom (quantum hadrodynamics) are presented, and the assumptions underlying this framework are discussed. Some applications and successes of quantum hadrodynamics are described, with an emphasis on the new features arising from relativity. Examples include the nuclear equation of state, the shell model, nucleon-nucleus scattering, and the inclusion of zero-point vacuum corrections. Current issues and problems are also considered, such as the construction of improved approximations, the full role of the quantum vacuum, and the relationship between quantum hadrodynamics and quantum chromodynamics. We also speculate on future developments. 103 refs., 18 figs.

  9. On a relativistic particle and a relativistic position-dependent mass particle subject to the Klein-Gordon oscillator and the Coulomb potential

    NASA Astrophysics Data System (ADS)

    Vitória, R. L. L.; Furtado, C.; Bakke, K.

    2016-07-01

    The relativistic quantum dynamics of an electrically charged particle subject to the Klein-Gordon oscillator and the Coulomb potential is investigated. By searching for relativistic bound states, a particular quantum effect can be observed: a dependence of the angular frequency of the Klein-Gordon oscillator on the quantum numbers of the system. The meaning of this behaviour of the angular frequency is that only some specific values of the angular frequency of the Klein-Gordon oscillator are permitted in order to obtain bound state solutions. As an example, we obtain both the angular frequency and the energy level associated with the ground state of the relativistic system. Further, we analyse the behaviour of a relativistic position-dependent mass particle subject to the Klein-Gordon oscillator and the Coulomb potential.

  10. Exact tensor hypercontraction: a universal technique for the resolution of matrix elements of local finite-range N-body potentials in many-body quantum problems.

    PubMed

    Parrish, Robert M; Hohenstein, Edward G; Schunck, Nicolas F; Sherrill, C David; Martínez, Todd J

    2013-09-27

    Configuration-space matrix elements of N-body potentials arise naturally and ubiquitously in the Ritz-Galerkin solution of many-body quantum problems. For the common specialization of local, finite-range potentials, we develop the exact tensor hypercontraction method, which provides a quantized renormalization of the coordinate-space form of the N-body potential, allowing for a highly separable tensor factorization of the configuration-space matrix elements. This representation allows for substantial computational savings in chemical, atomic, and nuclear physics simulations, particularly with respect to difficult "exchangelike" contractions. PMID:24116775

  11. Shielding of relativistic protons.

    PubMed

    Bertucci, A; Durante, M; Gialanella, G; Grossi, G; Manti, L; Pugliese, M; Scampoli, P; Mancusi, D; Sihver, L; Rusek, A

    2007-06-01

    Protons are the most abundant element in the galactic cosmic radiation, and the energy spectrum peaks around 1 GeV. Shielding of relativistic protons is therefore a key problem in the radiation protection strategy of crewmembers involved in long-term missions in deep space. Hydrogen ions were accelerated up to 1 GeV at the NASA Space Radiation Laboratory, Brookhaven National Laboratory, New York. The proton beam was also shielded with thick (about 20 g/cm2) blocks of lucite (PMMA) or aluminium (Al). We found that the dose rate was increased 40-60% by the shielding and decreased as a function of the distance along the axis. Simulations using the General-Purpose Particle and Heavy-Ion Transport code System (PHITS) show that the dose increase is mostly caused by secondary protons emitted by the target. The modified radiation field after the shield has been characterized for its biological effectiveness by measuring chromosomal aberrations in human peripheral blood lymphocytes exposed just behind the shield block, or to the direct beam, in the dose range 0.5-3 Gy. Notwithstanding the increased dose per incident proton, the fraction of aberrant cells at the same dose in the sample position was not significantly modified by the shield. The PHITS code simulations show that, albeit secondary protons are slower than incident nuclei, the LET spectrum is still contained in the low-LET range (<10 keV/microm), which explains the approximately unitary value measured for the relative biological effectiveness. PMID:17256178

  12. Relativistic differential-difference momentum operators and noncommutative differential calculus

    SciTech Connect

    Mir-Kasimov, R. M.

    2013-09-15

    The relativistic kinetic momentum operators are introduced in the framework of the Quantum Mechanics (QM) in the Relativistic Configuration Space (RCS). These operators correspond to the half of the non-Euclidean distance in the Lobachevsky momentum space. In terms of kinetic momentum operators the relativistic kinetic energy is separated as the independent term of the total Hamiltonian. This relativistic kinetic energy term is not distinguishing in form from its nonrelativistic counterpart. The role of the plane wave (wave function of the motion with definite value of momentum and energy) plays the generating function for the matrix elements of the unitary irreps of Lorentz group (generalized Jacobi polynomials). The kinetic momentum operators are the interior derivatives in the framework of the noncommutative differential calculus over the commutative algebra generated by the coordinate functions over the RCS.

  13. A relativistically interacting exactly solvable multi-time model for two massless Dirac particles in 1 + 1 dimensions

    SciTech Connect

    Lienert, Matthias

    2015-04-15

    The question how to Lorentz transform an N-particle wave function naturally leads to the concept of a so-called multi-time wave function, i.e., a map from (space-time){sup N} to a spin space. This concept was originally proposed by Dirac as the basis of relativistic quantum mechanics. In such a view, interaction potentials are mathematically inconsistent. This fact motivates the search for new mechanisms for relativistic interactions. In this paper, we explore the idea that relativistic interaction can be described by boundary conditions on the set of coincidence points of two particles in space-time. This extends ideas from zero-range physics to a relativistic setting. We illustrate the idea at the simplest model which still possesses essential physical properties like Lorentz invariance and a positive definite density: two-time equations for massless Dirac particles in 1 + 1 dimensions. In order to deal with a spatio-temporally non-trivial domain, a necessity in the multi-time picture, we develop a new method to prove existence and uniqueness of classical solutions: a generalized version of the method of characteristics. Both mathematical and physical considerations are combined to precisely formulate and answer the questions of probability conservation, Lorentz invariance, interaction, and antisymmetry.

  14. Relativistic Dipole Matrix Element Zeros

    NASA Astrophysics Data System (ADS)

    Lajohn, L. A.; Pratt, R. H.

    2002-05-01

    There is a special class of relativistic high energy dipole matrix element zeros (RZ), whose positions with respect to photon energy ω , only depend on the bound state l quantum number according to ω^0=mc^2/(l_b+1) (independent of primary quantum number n, nuclear charge Z, central potential V and dipole retardation). These RZ only occur in (n,l_b,j_b)arrow (ɛ , l_b+1,j_b) transitions such as ns_1/2arrow ɛ p_1/2; np_3/2arrow ɛ d_3/2: nd_5/2arrow ɛ f_5/2 etc. The nonrelativistic limit of these matrix elements can be established explicitly in the Coulomb case. Within the general matrix element formalism (such as that in [1]); when |κ | is substituted for γ in analytic expressions for matrix elements, the zeros remain, but ω^0 now becomes dependent on n and Z. When the reduction to nonrelativistic form is completed by application of the low energy approximation ω mc^2 mc^2, the zeros disappear. This nonzero behavior was noted in nonrelativistic dipole Coulomb matrix elements by Fano and Cooper [2] and later proven by Oh and Pratt[3]. (J. H. Scofield, Phys. Rev. A 40), 3054 (1989 (U. Fano and J. W. Cooper, Rev. Mod. Phys. 40), 441 (1968). (D. Oh and R. H. Pratt, Phys. Rev. A 34), 2486 (1986); 37, 1524 (1988); 45, 1583 (1992).

  15. On the description of subsystems in relativistic hypersurface Bohmian mechanics.

    PubMed

    Dürr, Detlef; Lienert, Matthias

    2014-09-01

    A candidate for a realistic relativistic quantum theory is the hypersurface Bohm-Dirac model. Its formulation uses a foliation of space-time into space-like hypersurfaces. In order to apply the theory and to make contact with the usual quantum formalism, one needs a framework for the description of subsystems. The presence of spin together with the foliation renders the subsystem description more complicated than in the non-relativistic case with spin. In this paper, we provide such a framework in terms of an appropriate conditional density matrix and an effective wave function as well as clarify their relation, thereby generalizing previous subsystem descriptions in the non-relativistic case. PMID:25197244

  16. Relativistic corrections to the pair Bc-meson production in e+e- annihilation

    NASA Astrophysics Data System (ADS)

    Karyasov, A. A.; Martynenko, A. P.; Martynenko, F. A.

    2016-10-01

    Relativistic corrections to the pair Bc-meson production in e+e--annihilation are calculated. We investigate a production of pair pseudoscalar, vector and pseudoscalar+vector Bc-mesons in the leading order perturbative quantum chromodynamics and relativistic quark model. Relativistic expressions of the pair production cross sections are obtained. Their numerical evaluation shows that relativistic effects in the production amplitudes and bound state wave functions three times reduce nonrelativistic results at the center-of-mass energy s = 22 GeV.

  17. 2.3 µm range InP-based type-II quantum well Fabry-Perot lasers heterogeneously integrated on a silicon photonic integrated circuit.

    PubMed

    Wang, Ruijun; Sprengel, Stephan; Boehm, Gerhard; Muneeb, Muhammad; Baets, Roel; Amann, Markus-Christian; Roelkens, Gunther

    2016-09-01

    Heterogeneously integrated InP-based type-II quantum well Fabry-Perot lasers on a silicon waveguide circuit emitting in the 2.3 µm wavelength range are demonstrated. The devices consist of a "W"-shaped InGaAs/GaAsSb multi-quantum-well gain section, III-V/silicon spot size converters and two silicon Bragg grating reflectors to form the laser cavity. In continuous-wave (CW) operation, we obtain a threshold current density of 2.7 kA/cm2 and output power of 1.3 mW at 5 °C for 2.35 μm lasers. The lasers emit over 3.7 mW of peak power with a threshold current density of 1.6 kA/cm2 in pulsed regime at room temperature. This demonstration of heterogeneously integrated lasers indicates that the material system and heterogeneous integration method are promising to realize fully integrated III-V/silicon photonics spectroscopic sensors in the 2 µm wavelength range.

  18. 2.3 µm range InP-based type-II quantum well Fabry-Perot lasers heterogeneously integrated on a silicon photonic integrated circuit.

    PubMed

    Wang, Ruijun; Sprengel, Stephan; Boehm, Gerhard; Muneeb, Muhammad; Baets, Roel; Amann, Markus-Christian; Roelkens, Gunther

    2016-09-01

    Heterogeneously integrated InP-based type-II quantum well Fabry-Perot lasers on a silicon waveguide circuit emitting in the 2.3 µm wavelength range are demonstrated. The devices consist of a "W"-shaped InGaAs/GaAsSb multi-quantum-well gain section, III-V/silicon spot size converters and two silicon Bragg grating reflectors to form the laser cavity. In continuous-wave (CW) operation, we obtain a threshold current density of 2.7 kA/cm2 and output power of 1.3 mW at 5 °C for 2.35 μm lasers. The lasers emit over 3.7 mW of peak power with a threshold current density of 1.6 kA/cm2 in pulsed regime at room temperature. This demonstration of heterogeneously integrated lasers indicates that the material system and heterogeneous integration method are promising to realize fully integrated III-V/silicon photonics spectroscopic sensors in the 2 µm wavelength range. PMID:27607711

  19. Form factor for a two-particle system within a relativistic quasipotential approach: Case of arbitrary masses and of a vector current

    SciTech Connect

    Chernichenko, Yu. D. E-mail: chyud@mail.ru

    2015-03-15

    A new relativistic form factor for a bound two-particle system was obtained for the case of a vector current. The present consideration was performed within the relativistic quasipotential approach based on the covariant Hamiltonian formulation of quantum field theory by going over to the three-dimensional relativistic configuration representation for the case of interaction between two relativistic spinless particles of arbitrary mass.

  20. Relativistic Weierstrass random walks.

    PubMed

    Saa, Alberto; Venegeroles, Roberto

    2010-08-01

    The Weierstrass random walk is a paradigmatic Markov chain giving rise to a Lévy-type superdiffusive behavior. It is well known that special relativity prevents the arbitrarily high velocities necessary to establish a superdiffusive behavior in any process occurring in Minkowski spacetime, implying, in particular, that any relativistic Markov chain describing spacetime phenomena must be essentially Gaussian. Here, we introduce a simple relativistic extension of the Weierstrass random walk and show that there must exist a transition time t{c} delimiting two qualitative distinct dynamical regimes: the (nonrelativistic) superdiffusive Lévy flights, for trelativistic) Gaussian diffusion, for t>t{c} . Implications of this crossover between different diffusion regimes are discussed for some explicit examples. The study of such an explicit and simple Markov chain can shed some light on several results obtained in much more involved contexts. PMID:20866862

  1. Relativistic Bursian diode equilibria

    SciTech Connect

    Ender, A. Y.; Kuznetsov, V. I.; Schamel, H.

    2011-03-15

    A comprehensive study of steady-states of a planar vacuum diode driven by a cold relativistic electron beam is presented. The emitter electric field as a characteristic function for their existence is evaluated in dependence of the diode length, the applied potential V, and the relativistic beam factor at injection {gamma}{sub 0}. It is used to classify the different branches of possible solutions, which encompass electron flows that are (i) transmitted through the diode completely, (ii) partially reflected from a virtual cathode (VC) either within the diode region or at the collector side, and (iii) reflected totally. As a byproduct, the V and {gamma}{sub 0} dependences of both bifurcation points of the minimum potential and of the transmitted current are obtained and the ultrarelativistic limit, {gamma}{sub 0}>>1, is performed. In this highly relativistic regime, the density of electrons appears to be constant across the diode region except for a small area around the VC.

  2. Relativistic Weierstrass random walks.

    PubMed

    Saa, Alberto; Venegeroles, Roberto

    2010-08-01

    The Weierstrass random walk is a paradigmatic Markov chain giving rise to a Lévy-type superdiffusive behavior. It is well known that special relativity prevents the arbitrarily high velocities necessary to establish a superdiffusive behavior in any process occurring in Minkowski spacetime, implying, in particular, that any relativistic Markov chain describing spacetime phenomena must be essentially Gaussian. Here, we introduce a simple relativistic extension of the Weierstrass random walk and show that there must exist a transition time t{c} delimiting two qualitative distinct dynamical regimes: the (nonrelativistic) superdiffusive Lévy flights, for trelativistic) Gaussian diffusion, for t>t{c} . Implications of this crossover between different diffusion regimes are discussed for some explicit examples. The study of such an explicit and simple Markov chain can shed some light on several results obtained in much more involved contexts.

  3. Magnetogenesis through Relativistic Velocity Shear

    NASA Astrophysics Data System (ADS)

    Miller, Evan

    Magnetic fields at all scales are prevalent in our universe. However, current cosmological models predict that initially the universe was bereft of large-scale fields. Standard magnetohydrodynamics (MHD) does not permit magnetogenesis; in the MHD Faraday's law, the change in magnetic field B depends on B itself. Thus if B is initially zero, it will remain zero for all time. A more accurate physical model is needed to explain the origins of the galactic-scale magnetic fields observed today. In this thesis, I explore two velocity-driven mechanisms for magnetogenesis in 2-fluid plasma. The first is a novel kinematic 'battery' arising from convection of vorticity. A coupling between thermal and plasma oscillations, this non-relativistic mechanism can operate in flows that are incompressible, quasi-neutral and barotropic. The second mechanism results from inclusion of thermal effects in relativistic shear flow instabilities. In such flows, parallel perturbations are ubiquitously unstable at small scales, with growth rates of order with the plasma frequency over a defined range of parameter-space. Of these two processes, instabilities seem far more likely to account for galactic magnetic fields. Stable kinematic effects will, at best, be comparable to an ideal Biermann battery, which is suspected to be orders of magnitude too weak to produce the observed galactic fields. On the other hand, instabilities grow until saturation is reached, a topic that has yet to be explored in detail on cosmological scales. In addition to investigating these magnetogenesis sources, I derive a general dispersion relation for three dimensional, warm, two species plasma with discontinuous shear flow. The mathematics of relativistic plasma, sheared-flow instability and the Biermann battery are also discussed.

  4. Novel Quantum Criticality in Two Dimensional Topological Phase transitions

    PubMed Central

    Cho, Gil Young; Moon, Eun-Gook

    2016-01-01

    Topological quantum phase transitions intrinsically intertwine self-similarity and topology of many-electron wave-functions, and divining them is one of the most significant ways to advance understanding in condensed matter physics. Our focus is to investigate an unconventional class of the transitions between insulators and Dirac semimetals whose description is beyond conventional pseudo relativistic Dirac Hamiltonian. At the transition without the long-range Coulomb interaction, the electronic energy dispersion along one direction behaves like a relativistic particle, linear in momentum, but along the other direction it behaves like a non-relativistic particle, quadratic in momentum. Various physical systems ranging from TiO2-VO2 heterostructure to organic material α-(BEDT-TTF)2I3 under pressure have been proposed to have such anisotropic dispersion relation. Here, we discover a novel quantum criticality at the phase transition by incorporating the long range Coulomb interaction. Unique interplay between the Coulomb interaction and electronic critical modes enforces not only the anisotropic renormalization of the Coulomb interaction but also marginally modified electronic excitation. In connection with experiments, we investigate several striking effects in physical observables of our novel criticality. PMID:26791803

  5. 1.55-μm mode-locked quantum-dot lasers with 300 MHz frequency tuning range

    SciTech Connect

    Sadeev, T. Arsenijević, D.; Bimberg, D.; Franke, D.; Kreissl, J.; Künzel, H.

    2015-01-19

    Passive mode-locking of two-section quantum-dot mode-locked lasers grown by metalorganic vapor phase epitaxy on InP is reported. 1250-μm long lasers exhibit a wide tuning range of 300 MHz around the fundamental mode-locking frequency of 33.48 GHz. The frequency tuning is achieved by varying the reverse bias of the saturable absorber from 0 to −2.2 V and the gain section current from 90 to 280 mA. 3 dB optical spectra width of 6–7 nm leads to ex-facet optical pulses with full-width half-maximum down to 3.7 ps. Single-section quantum-dot mode-locked lasers show 0.8 ps broad optical pulses after external fiber-based compression. Injection current tuning from 70 to 300 mA leads to 30 MHz frequency tuning.

  6. Study of optically trapped living Trypanosoma cruzi/Trypanosoma rangeli - Rhodnius prolixus interactions by real time confocal images using CdSe quantum dots

    NASA Astrophysics Data System (ADS)

    de Thomaz, A. A.; Almeida, D. B.; Faustino, W. M.; Jacob, G. J.; Fontes, A.; Barbosa, L. C.; Cesar, C. L.; Stahl, C. V.; Santos-Mallet, J. R.; Gomes, S. A. O.; Feder, D.

    2008-08-01

    One of the fundamental goals in biology is to understand the interplay between biomolecules of different cells. This happen, for example, in the first moments of the infection of a vector by a parasite that results in the adherence to the cell walls. To observe this kind of event we used an integrated Optical Tweezers and Confocal Microscopy tool. This tool allow us to use the Optical Tweezers to trigger the adhesion of the Trypanosoma cruzi and Trypanosoma rangeli parasite to the intestine wall cells and salivary gland of the Rhodnius prolixus vector and to, subsequently observe the sequence of events by confocal fluorescence microscopy under optical forces stresses. We kept the microorganism and vector cells alive using CdSe quantum dot staining. Besides the fact that Quantum Dots are bright vital fluorescent markers, the absence of photobleaching allow us to follow the events in time for an extended period. By zooming to the region of interested we have been able to acquire confocal images at the 2 to 3 frames per second rate.

  7. Mathematical structure of relativistic Coulomb integrals

    NASA Astrophysics Data System (ADS)

    Suslov, Sergei K.

    2010-03-01

    We show that the diagonal matrix elements , where O={1,β,iαnβ} are the standard Dirac matrix operators and the angular brackets denote the quantum-mechanical average for the relativistic Coulomb problem, may be considered as difference analogs of the radial wave functions. Such structure provides an independent way of obtaining closed forms of these matrix elements by elementary methods of the theory of difference equations without explicit evaluation of the integrals. Three-term recurrence relations for each of these expectation values are derived as a by-product. Transformation formulas for the corresponding generalized hypergeometric series are discussed.

  8. Optical conductivity of warm dense matter within a wide frequency range using quantum statistical and kinetic approaches

    NASA Astrophysics Data System (ADS)

    Veysman, M.; Röpke, G.; Winkel, M.; Reinholz, H.

    2016-07-01

    Fundamental properties of warm dense matter are described by the dielectric function, which gives access to the frequency-dependent electrical conductivity; absorption, emission, and scattering of radiation; charged particles stopping; and further macroscopic properties. Different approaches to the dielectric function and the related dynamical collision frequency are compared in a wide frequency range. The high-frequency limit describing inverse bremsstrahlung and the low-frequency limit of the dc conductivity are considered. Sum rules and Kramers-Kronig relation are checked for the generalized linear response theory and the standard approach following kinetic theory. The results are discussed in application to aluminum, xenon, and argon plasmas.

  9. Optical conductivity of warm dense matter within a wide frequency range using quantum statistical and kinetic approaches.

    PubMed

    Veysman, M; Röpke, G; Winkel, M; Reinholz, H

    2016-07-01

    Fundamental properties of warm dense matter are described by the dielectric function, which gives access to the frequency-dependent electrical conductivity; absorption, emission, and scattering of radiation; charged particles stopping; and further macroscopic properties. Different approaches to the dielectric function and the related dynamical collision frequency are compared in a wide frequency range. The high-frequency limit describing inverse bremsstrahlung and the low-frequency limit of the dc conductivity are considered. Sum rules and Kramers-Kronig relation are checked for the generalized linear response theory and the standard approach following kinetic theory. The results are discussed in application to aluminum, xenon, and argon plasmas. PMID:27575226

  10. The Relativistic Rocket

    ERIC Educational Resources Information Center

    Antippa, Adel F.

    2009-01-01

    We solve the problem of the relativistic rocket by making use of the relation between Lorentzian and Galilean velocities, as well as the laws of superposition of successive collinear Lorentz boosts in the limit of infinitesimal boosts. The solution is conceptually simple, and technically straightforward, and provides an example of a powerful…

  11. Radiation from Relativistic Jets

    NASA Technical Reports Server (NTRS)

    Nishikawa, K.-I.; Mizuno, Y.; Hardee, P.; Sol, H.; Medvedev, M.; Zhang, B.; Nordlund, A.; Frederiksen, J. T.; Fishman, G. J.; Preece, R.

    2008-01-01

    Nonthermal radiation observed from astrophysical systems containing relativistic jets and shocks, e.g., gamma-ray bursts (GRBs), active galactic nuclei (AGNs), and Galactic microquasar systems usually have power-law emission spectra. Recent PIC simulations of relativistic electron-ion (electron-positron) jets injected into a stationary medium show that particle acceleration occurs within the downstream jet. In the presence of relativistic jets, instabilities such as the Buneman instability, other two-streaming instability, and the Weibel (filamentation) instability create collisionless shocks, which are responsible for particle (electron, positron, and ion) acceleration. The simulation results show that the Weibel instability is responsible for generating and amplifying highly nonuniform, small-scale magnetic fields. These magnetic fields contribute to the electron's transverse deflection behind the jet head. The 'jitter' radiation from deflected electrons in small-scale magnetic fields has different properties than synchrotron radiation which is calculated in a uniform magnetic field. This jitter radiation, a case of diffusive synchrotron radiation, may be important to understand the complex time evolution and/or spectral structure in gamma-ray bursts, relativistic jets, and supernova remnants.

  12. The Euler current and relativistic parity odd transport

    NASA Astrophysics Data System (ADS)

    Golkar, Siavash; Roberts, Matthew M.; Son, Dam T.

    2015-04-01

    For a spacetime of odd dimensions endowed with a unit vector field, we introduce a new topological current that is identically conserved and whose charge is equal to the Euler character of the even dimensional spacelike foliations. The existence of this current allows us to introduce new Chern-Simons-type terms in the effective field theories describing relativistic quantum Hall states and (2 + 1) dimensional superfluids. Using effective field theory, we calculate various correlation functions and identify transport coefficients. In the quantum Hall case, this current provides the natural relativistic generalization of the Wen-Zee term, required to characterize the shift and Hall viscosity in quantum Hall systems. For the superfluid case this term is required to have nonzero Hall viscosity and to describe superfluids with non s-wave pairing.

  13. Relativistic effects on plasma expansion

    SciTech Connect

    Benkhelifa, El-Amine; Djebli, Mourad

    2014-07-15

    The expansion of electron-ion plasma is studied through a fully relativistic multi-fluids plasma model which includes thermal pressure, ambipolar electrostatic potential, and internal energy conversion. Numerical investigation, based on quasi-neutral assumption, is performed for three different regimes: nonrelativistic, weakly relativistic, and relativistic. Ions' front in weakly relativistic regime exhibits spiky structure associated with a break-down of quasi-neutrality at the expanding front. In the relativistic regime, ion velocity is found to reach a saturation limit which occurs at earlier stages of the expansion. This limit is enhanced by higher electron velocity.

  14. Photoluminescence quantum yields of PbSe and PbS QDs in the range of 1000 nm to 2000 nm (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Beard, Matthew C.; Semonin, Octavi E.; Johnson, Justin C.; Marshall, Ashley; Zhang, Jianbing; Chernomordik, Boris D.

    2016-03-01

    PbS and PbSe quantum dots (QDs) are promising strong infrared emitters. We have developed several synthetic routes to producing PbS and PbSe QDs with a variety of sizes such that the bandgap can be continuously tuned from 2000 to 1000 nm. We provide a simple and accurate synthetic route to reproducibly produce PbS QDs with a narrow size-distribution and high chemical yield. The different synthetic routes lead to differences in their surface chemistry and to differences in their air stability and photoluminescence quantum yields (PLQY). To characterize the PLQY we directly measured the PLQY IR-26 (a standard IR emitting organic dye) at a range of concentrations as well as the PLQY of PbS and PbSe QDs for a range of sizes. We find that the PLQY of IR-26 has a weak concentration dependence due to reabsorption, with a PLQY of 0:048_0:002% for low concentrations, lower than previous reports by a full order of magnitude. We also find a dramatic size dependence for both PbS and PbSe QDs, with the smallest dots exhibiting a PLQY in excess of 60% while larger dots fall below 3%. A model, including nonradiative transition between electronic states and energy transfer to ligand vibrations, appears to explain this size dependence. These findings provide both a better characterization of photoluminescence for near infrared emitters. Halogen surface passivation provides both a larger PLQY (~ 30% improvement) as well as increased air stability.

  15. Theoretical grounds of relativistic methods for calculation of spin-spin coupling constants in nuclear magnetic resonance spectra

    NASA Astrophysics Data System (ADS)

    Rusakova, I. L.; Rusakov, Yu Yu; Krivdin, L. B.

    2016-04-01

    The theoretical grounds of the modern relativistic methods for quantum chemical calculation of spin-spin coupling constants in nuclear magnetic resonance spectra are considered. Examples and prospects of application of relativistic calculations of these constants in the structural studies of organic and heteroorganic compounds are discussed. Practical recommendations on relativistic calculations of spin-spin coupling constants using the available software are given. The bibliography includes 622 references.

  16. Theoretical grounds of relativistic methods for calculation of spin–spin coupling constants in nuclear magnetic resonance spectra

    NASA Astrophysics Data System (ADS)

    Rusakova, I. L.; Rusakov, Yu Yu; Krivdin, L. B.

    2016-04-01

    The theoretical grounds of the modern relativistic methods for quantum chemical calculation of spin–spin coupling constants in nuclear magnetic resonance spectra are considered. Examples and prospects of application of relativistic calculations of these constants in the structural studies of organic and heteroorganic compounds are discussed. Practical recommendations on relativistic calculations of spin–spin coupling constants using the available software are given. The bibliography includes 622 references.

  17. Generalized charge-screening in relativistic Thomas–Fermi model

    SciTech Connect

    Akbari-Moghanjoughi, M.

    2014-10-15

    In this paper, we study the charge shielding within the relativistic Thomas-Fermi model for a wide range of electron number-densities and the atomic-number of screened ions. A generalized energy-density relation is obtained using the force-balance equation and taking into account the Chandrasekhar's relativistic electron degeneracy pressure. By numerically solving a second-order nonlinear differential equation, the Thomas-Fermi screening length is investigated, and the results are compared for three distinct regimes of the solid-density, warm-dense-matter, and white-dwarfs (WDs). It is revealed that our nonlinear screening theory is compatible with the exponentially decaying Thomas-Fermi-type shielding predicted by the linear response theory. Moreover, the variation of relative Thomas-Fermi screening length shows that extremely dense quantum electron fluids are relatively poor charge shielders. Calculation of the total number of screening electrons around a nucleus shows that there is a position of maximum number of screening localized electrons around the screened nucleus, which moves closer to the point-like nucleus by increase in the plasma number density but is unaffected due to increase in the atomic-number value. It is discovered that the total number of screening electrons, (N{sub s}∝r{sub TF}{sup 3}/r{sub d}{sup 3} where r{sub TF} and r{sub d} are the Thomas-Fermi and interparticle distance, respectively) has a distinct limit for extremely dense plasmas such as WD-cores and neutron star crusts, which is unique for all given values of the atomic-number. This is equal to saying that in an ultrarelativistic degeneracy limit of electron-ion plasma, the screening length couples with the system dimensionality and the plasma becomes spherically self-similar. Current analysis can provide useful information on the effects of relativistic correction to the charge screening for a wide range of plasma density, such as the inertial-confined plasmas and compact stellar

  18. Au-induced quantum chains on Ge(001)-symmetries, long-range order and the conduction path.

    PubMed

    Blumenstein, C; Meyer, S; Mietke, S; Schäfer, J; Bostwick, A; Rotenberg, E; Matzdorf, R; Claessen, R

    2013-01-01

    Atomic nanowires on the Au/Ge(001) surface are investigated for their structural and electronic properties using scanning tunneling microscopy (STM) and angle-resolved photoemission spectroscopy (ARPES). STM reveals two distinct symmetries: a c(8 × 2) describing the basic repeating distances, while the fine structure on top of the wires causes an additional superstructure of p(4 × 1). Both symmetries are long-range ordered as judged from low-energy electron diffraction. The Fermi surface is composed of almost perfectly straight sheets. Thus, the electronic states are one-dimensionally confined. Spatial dI/dV maps, where both topography and density of states (DOS) are probed simultaneously, reveal that the DOS at low energies, i.e. the conduction path, is oriented along the chain direction. This is fully consistent with the recently reported Tomonaga-Luttinger liquid phase of Au/Ge(001), with the density of states being suppressed by a power-law towards the Fermi energy. PMID:23220774

  19. Pair correlations, short-range order, and dispersive excitations in the quasi-kagome quantum magnet volborthite

    NASA Astrophysics Data System (ADS)

    Nilsen, G. J.; Coomer, F. C.; de Vries, M. A.; Stewart, J. R.; Deen, P. P.; Harrison, A.; Rønnow, H. M.

    2011-11-01

    We present spatial and dynamic information on the s=1/2 distorted kagome antiferromagnet volborthite, Cu3V2O7(OD)2·2D2O, obtained by polarized and inelastic neutron scattering. The instantaneous structure factor, S(Q), is dominated by nearest-neighbor pair correlations, with short-range order at wave vectors Q1=0.65(3) Å-1 and Q2=1.15(5) Å-1 emerging below 5 K. The excitation spectrum, S(Q,ω), reveals two steep branches dispersing from Q1 and Q2, and a flat mode at ωf=5.0(2) meV. The results allow us to identify the crossover at T*˜1 K in 51V NMR and specific-heat measurements as the buildup of correlations at Q1. We compare our data to theoretical models proposed for volborthite, and also demonstrate that the excitation spectrum can be explained by spin-wave-like excitations with anisotropic exchange parameters, as suggested by recent local-density calculations.

  20. Au-induced quantum chains on Ge(001)-symmetries, long-range order and the conduction path.

    PubMed

    Blumenstein, C; Meyer, S; Mietke, S; Schäfer, J; Bostwick, A; Rotenberg, E; Matzdorf, R; Claessen, R

    2013-01-01

    Atomic nanowires on the Au/Ge(001) surface are investigated for their structural and electronic properties using scanning tunneling microscopy (STM) and angle-resolved photoemission spectroscopy (ARPES). STM reveals two distinct symmetries: a c(8 × 2) describing the basic repeating distances, while the fine structure on top of the wires causes an additional superstructure of p(4 × 1). Both symmetries are long-range ordered as judged from low-energy electron diffraction. The Fermi surface is composed of almost perfectly straight sheets. Thus, the electronic states are one-dimensionally confined. Spatial dI/dV maps, where both topography and density of states (DOS) are probed simultaneously, reveal that the DOS at low energies, i.e. the conduction path, is oriented along the chain direction. This is fully consistent with the recently reported Tomonaga-Luttinger liquid phase of Au/Ge(001), with the density of states being suppressed by a power-law towards the Fermi energy.

  1. Au-induced quantum chains on Ge(001)—symmetries, long-range order and the conduction path

    NASA Astrophysics Data System (ADS)

    Blumenstein, C.; Meyer, S.; Mietke, S.; Schäfer, J.; Bostwick, A.; Rotenberg, E.; Matzdorf, R.; Claessen, R.

    2013-01-01

    Atomic nanowires on the Au/Ge(001) surface are investigated for their structural and electronic properties using scanning tunneling microscopy (STM) and angle-resolved photoemission spectroscopy (ARPES). STM reveals two distinct symmetries: a c(8 × 2) describing the basic repeating distances, while the fine structure on top of the wires causes an additional superstructure of p(4 × 1). Both symmetries are long-range ordered as judged from low-energy electron diffraction. The Fermi surface is composed of almost perfectly straight sheets. Thus, the electronic states are one-dimensionally confined. Spatial dI/dV maps, where both topography and density of states (DOS) are probed simultaneously, reveal that the DOS at low energies, i.e. the conduction path, is oriented along the chain direction. This is fully consistent with the recently reported Tomonaga-Luttinger liquid phase of Au/Ge(001), with the density of states being suppressed by a power-law towards the Fermi energy.

  2. Classical fields method for a relativistic interacting Bose gas

    SciTech Connect

    Witkowska, Emilia; Zin, Pawel; Gajda, Mariusz

    2009-01-15

    We formulate a classical fields method for the description of relativistic interacting bosonic particles at nonzero temperatures. The method relies on the assumption that at low temperatures the Bose field can be described by a c-number function. We discuss a very important role of the cutoff momentum which divides the field into a dominant classical part and a small quantum correction. We illustrate the method by studying the thermodynamics of a relativistic Bose field which is governed by the Klein-Gordon equation with a {lambda}{psi}{sup 4} term responsible for the interactions.

  3. Microscopic picture of non-relativistic classicalons

    SciTech Connect

    Berkhahn, Felix; Müller, Sophia; Niedermann, Florian; Schneider, Robert E-mail: sophia.x.mueller@physik.uni-muenchen.de E-mail: robert.bob.schneider@physik.uni-muenchen.de

    2013-08-01

    A theory of a non-relativistic, complex scalar field with derivatively coupled interaction terms is investigated. This toy model is considered as a prototype of a classicalizing theory and in particular of general relativity, for which the black hole constitutes a prominent example of a classicalon. Accordingly, the theory allows for a non-trivial solution of the stationary Gross-Pitaevskii equation corresponding to a black hole in the case of GR. Quantum fluctuations on this classical background are investigated within the Bogoliubov approximation. It turns out that the perturbative approach is invalidated by a high occupation of the Bogoliubov modes. Recently, it was proposed that a black hole is a Bose-Einstein condensate of gravitons that dynamically ensures to stay at the verge of a quantum phase transition. Our result is understood as an indication for that claim. Furthermore, it motivates a non-linear numerical analysis of the model.

  4. The Relativistic Heavy Ion Collider

    NASA Astrophysics Data System (ADS)

    Fischer, Wolfram

    The Relativistic Heavy Ion Collider (RHIC), shown in Fig. 1, was build to study the interactions of quarks and gluons at high energies [Harrison, Ludlam and Ozaki (2003)]. The theory of Quantum Chromodynamics (QCD) describes these interactions. One of the main goals for the RHIC experiments was the creation and study of the Quark-Gluon Plasma (QGP), which was expected to be formed after the collision of heavy ions at a temperature of approximately 2 trillion kelvin (or equivalently an energy of 150 MeV). The QGP is the substance which existed only a few microseconds after the Big Bang. The QGP was anticipated to be weakly interacting like a gas but turned out to be strongly interacting and more like a liquid. Among its unusual properties is its extremely low viscosity [Auerbach and Schlomo (2009)], which makes the QGP the substance closest to a perfect liquid known to date. The QGP is opaque to moderate energy quarks and gluons leading to a phenomenon called jet quenching, where of a jet and its recoil jet only one is observable and the other suppressed after traversing and interacting with the QGP [Jacak and Müller (2012)]...

  5. Relativistic Pseudospin Symmetry

    SciTech Connect

    Ginocchio, Joseph N.

    2011-05-06

    We show that the pseudospin symmetry that Akito Arima discovered many years ago (with collaborators) is a symmetry of the the Dirac Hamiltonian for which the sum of the scalar and vector potentials are a constant. In this paper we discuss some of the implications of this relativistic symmetry and the experimental data that support these predictions. In his original paper Akito also discussed pseudo-U(3) symmetry. We show that pseudo-U(3) symmetry is a symmetry of the Dirac Hamiltonian for which the sum of harmonic oscillator vector and scalar potentials are equal to a constant, and we give the generators of pseudo-U(3) symmetry. Going beyond the mean field we summarize new results on non relativistic shell model Hamiltonians that have pseudospin symmetry and pseudo-orbital angular momentum symmetry as a dynamical symmetries.

  6. Relativistic multiwave Cerenkov generators

    SciTech Connect

    Bugaev, S.P.; Cherepenin, V.A.; Kanavets, V.I.; Klimov, A.I.; Kopenkin, A.D.; Koshelev, V.I.; Popov, V.A.; Slepkov, A.I. )

    1990-06-01

    A review of research on relativistic multiwave Cherenkov generators (MWCG) is provided. Presented is the linear theory of these devices, allowing a detailed description of multiwave interaction of a relativistic electron beam with an electromagnetic field in an electro-dynamic superdimensional MWCG system. The results of theoretical research on the starting parameters of generation, power flows, and the structure of the radiated field in a MWCG of a 3-cm-wave band are reported. The experiments on obtaining and investigating high-power pulses of microwave radiation in a MWCG of 3-cm- and 8-mm-wavelength bands are described. In particular, the results of research on a MWCG with the power of 15 GW in a 3-cm-wavelength band and the power of 3 GW in a 8-mm-wavelength band are presented. The results of research of spatial and temporal coherence of such generator radiation are reported.

  7. Relativistic electrons in space.

    NASA Technical Reports Server (NTRS)

    Simnett, G. M.

    1972-01-01

    This paper reviews the current state of knowledge concerning relativistic electrons, above 0.3 MeV, in interplanetary space, as measured by detectors on board satellites operating beyond the influence of the magnetosphere. The electrons have a galactic component, which at the lower energies is subject both to solar modulation and to spasmodic 'quiet time' increases and a direct solar component correlated with flare activity. The recent measurements have established the form of the differential energy spectrum of solar flare electrons. Electrons have been detected from flares behind the visible solar disk. Relativistic electrons do not appear to leave the sun at the time of the flash phase of the flare, although there are several signatures of electron acceleration at this time. The delay is interpreted as taking place during the transport of the electrons through the lower corona.

  8. Dielectric cavity relativistic magnetron

    NASA Astrophysics Data System (ADS)

    Hashemi, S. M. A.

    2010-02-01

    An alteration in the structure of the A6 relativistic magnetron is proposed, which introduces an extra degree of freedom to its design and enhances many of its quality factors. This modification involves the partial filling of the cavities of the device with a low-loss dielectric material. The operation of a dielectric-filled A6 is simulated; the results indicate single-mode operation at the desired π mode and a substantially cleaner rf spectrum.

  9. Active Stand-off Detection of Gas Leaks Using a Short Range Hard-target Backscatter Differential Optical Absorption System Based on a Quantum Cascade Laser Transmitter

    NASA Astrophysics Data System (ADS)

    Diaz, Adrian; Thomas, Benjamin; Castillo, Paulo; Gross, Barry; Moshary, Fred

    2016-06-01

    Fugitive gas emissions from agricultural or industrial plants and gas pipelines are an important environmental concern as they can contribute to the global increase of greenhouse gas concentration. Moreover, they are also a security and safety concern because of possible risk of fire/explosion or toxicity. This study presents gas concentration measurements using a quantum cascade laser open path system (QCLOPS). The system retrieves the pathaveraged concentration of N2O and CH4 by collecting the backscattered light from a scattering target. The gas concentration measurements have a high temporal resolution (68 ms) and are achieved at sufficient range (up to 40 m, ~ 130 feet) with a detection limit of 2.6 ppm CH4 and 0.4 ppm for N2O. Given these characteristics, this system is promising for mobile/multidirectional remote detection and evaluation of gas leaks. The instrument is monostatic with a tunable QCL emitting at ~ 7.7 μm wavelength range. The backscattered radiation is collected by a Newtonian telescope and focused on an infrared light detector. Puffs of N2O and CH4 are released along the optical path to simulate a gas leak. The measured absorption spectrum is obtained using the thermal intra-pulse frequency chirped DFB QCL and is analyzed to obtain path averaged gas concentrations.

  10. Selective ablation of WHHLMI rabbit atherosclerotic plaque by quantum cascade laser in the 5.7 μm wavelength range for less-invasive laser angioplasty

    NASA Astrophysics Data System (ADS)

    Hashimura, Keisuke; Ishii, Katsunori; Akikusa, Naota; Edamura, Tadataka; Yoshida, Harumasa; Awazu, Kunio

    2013-06-01

    We investigated the potential of a compact and high-power quantum cascade laser (QCL) in the 5.7 μm wavelength range for less-invasive laser angioplasty. Atherosclerotic plaques consist mainly of cholesteryl esters. Radiation at a wavelength of 5.75 μm is strongly absorbed in C=O stretching vibration mode of cholesteryl esters. Our previous study achieved to make cutting differences between a normal artery and an atherosclerotic lesions using nanosecond pulsed laser by difference-frequency generation (DFG laser) at the wavelength of 5.75 μm. For applying this technique to clinical treatment, a compact laser device is required. In this study, QCL irradiation effects to a porcine normal aorta were compared with DFG laser. Subsequently, QCL irradiation effects on an atherosclerotic aorta of myocardial infarction-prone Watanabe heritable hyperlipidemic rabbit (WHHLMI rabbit) and a normal rabbit aorta were observed. As a result, the QCL could make cutting differences between the rabbit atherosclerotic and normal aortas. On the other hand, the QCL induced more thermal damage to porcine normal aorta than the DFG laser at the irradiation condition of comparable ablation depths. In conclusion, the possibility of less-invasive and selective treatment of atherosclerotic plaques using the QCL in the 5.7 μm wavelength range was revealed, although improvement of QCL was required to prevent the thermal damage of a normal artery.

  11. Evidence of quantum correction to conductivity and variable range hopping conduction in nano-crystalline Cu{sub 3}N thin film

    SciTech Connect

    Sahoo, Guruprasad Jain, Mahaveer K.

    2015-10-15

    We have investigated the temperature dependent carrier transport properties of nano-crystalline copper nitride thin films synthesized by modified activated reactive evaporation. The films, prepared in a Cu-rich growth condition are found to be highly disordered and the carrier transport in these films is mainly attributed to the impurity band conduction. We have observed that no single conduction mechanism is appropriate to elucidate the carrier transport in the entire temperature range of 20 – 300 K. Therefore, we have employed different conduction mechanisms in different temperature regimes. The carrier transport of the films in the low temperature regime (20 – 150 K) has been interpreted by implementing quantum correction to the conductivity. In the high temperature regime (200 – 300 K), the conduction mechanism has been successfully analyzed on the basis of Mott’s variable range hopping mechanism. Furthermore, it can be predicted that copper ions present at the surface of the crystallites are responsible for the hopping conduction mechanism.

  12. Communication: Quantum mechanics without wavefunctions

    SciTech Connect

    Schiff, Jeremy; Poirier, Bill

    2012-01-21

    We present a self-contained formulation of spin-free non-relativistic quantum mechanics that makes no use of wavefunctions or complex amplitudes of any kind. Quantum states are represented as ensembles of real-valued quantum trajectories, obtained by extremizing an action and satisfying energy conservation. The theory applies for arbitrary configuration spaces and system dimensionalities. Various beneficial ramifications--theoretical, computational, and interpretational--are discussed.

  13. Relativistic model of disk-jet variability

    NASA Astrophysics Data System (ADS)

    Mohan, P.; Mangalam, A.

    2014-07-01

    We present a relativistic model of disk-jet variability in the optical/UV and X-ray wavelengths from AGN. The model treats the kinematics of a bulk inflow in orbital motion in a relativistic thin disk. A part of the advected plasma continues in a helical orbital motion onto a relativistic jet shaped by a magnetic surface with foot points near the innermost stable circular orbit. The model, cast in Kerr geometry includes Doppler and gravitational shifts, aberration, light bending and time delay effects on the outgoing radiation. Light curves are simulated for studying effects of the relativistic beaming and the quasi-periodic oscillation (QPO) phenomena with resulting typical timescales ranging between a few 1000 s and a few days. A power law power spectral density shape results with a typical slope of ˜ -2.5. Also, using a model for the quality factor of the QPO, we place constraints on black hole mass, spin and the size of the emission region.

  14. Constraining relativistic models through heavy ion collisions

    SciTech Connect

    Menezes, D. P.; Providencia, C.; Chiapparini, M.; Bracco, M. E.; Delfino, A.; Malheiro, M.

    2007-12-15

    Relativistic models can be successfully applied to the description of compact star properties in nuclear astrophysics as well as to nuclear matter and finite nuclei properties, these studies taking place at low and moderate temperatures. Nevertheless, all results are model dependent, and so far it is unclear whether some of them should be discarded. Moreover, in the regime of hot hadronic matter, very few calculations exist using these relativistic models, in particular when applied to particle yields in heavy ion collisions. A very important investigation is the simulation of a supernova explosion that is based on the construction of an adequate equation of state that needs to be valid within very large ranges of temperatures (0 to 100 MeV at least) and densities (very low to ten times the nuclear saturation density at least). In the present work, we comment on the known constraints that can help the selection of adequate models in this wide regime and investigate the main differences that arise when the particle production during a Au+Au collision at the BNL Relativistic Heavy Ion Collider is calculated with different relativistic models. We conclude that most of the models investigated in the present work give a very good overall description of the data and make predictions for not yet measured particle ratios.

  15. Relativistic tidal disruption events

    NASA Astrophysics Data System (ADS)

    Levan, A.

    2012-12-01

    In March 2011 Swift detected an extremely luminous and long-lived outburst from the nucleus of an otherwise quiescent, low luminosity (LMC-like) galaxy. Named Swift J1644+57, its combination of high-energy luminosity (1048 ergs s-1 at peak), rapid X-ray variability (factors of >100 on timescales of 100 seconds) and luminous, rising radio emission suggested that we were witnessing the birth of a moderately relativistic jet (Γ ˜ 2 - 5), created when a star is tidally disrupted by the supermassive black hole in the centre of the galaxy. A second event, Swift J2058+0516, detected two months later, with broadly similar properties lends further weight to this interpretation. Taken together this suggests that a fraction of tidal disruption events do indeed create relativistic outflows, demonstrates their detectability, and also implies that low mass galaxies can host massive black holes. Here, I briefly outline the observational properties of these relativistic tidal flares observed last year, and their evolution over the first year since their discovery.

  16. Relativistic mean field for nuclear periphery

    NASA Astrophysics Data System (ADS)

    Gambhir, Y. K.; Bhagwat, A. A.

    2002-09-01

    The antiproton annihilation experiments help to extract so-called peripheral factors representing the ratio of neutron to proton densities at the annihilation site that is about 2.5 fm away from the half-density radius of the nucleus. The relativistic mean field (RMF) approach is used to calculate the peripheral factors. The RMF equations (with frozen gap) and relativistic Hartree-Bogoliubov (RHB) equations (with finite range Gogny interaction-D1S for pairing) are solved employing the basis expansion method. The RHB equations are also solved in the coordinate space using a large box (30 fm); with an effective zero range density dependent interaction (consistent with Gogny D1S interaction) for pairing. The results are analyzed to ascertain quantitatively the effect of using these different techniques for solving the RMF/RHB equations. The calculated peripheral factors obtained by solving RHB equations in the coordinate space are relatively closer to the corresponding experimental values.

  17. Quantum Optics

    NASA Astrophysics Data System (ADS)

    Orvil Scully, Marlan; Zubairy, Muhammad Suhail

    1997-09-01

    Quantum optics has witnessed significant theoretical and experimental developments in recent years. This book provides an in-depth and wide-ranging introduction to the subject, emphasizing throughout the basic principles and their applications. The book begins by developing the basic tools of quantum optics, and goes on to show the application of these tools in a variety of quantum optical systems, including lasing without inversion, squeezed states, and atom optics. The final four chapters discuss quantum optical tests of the foundations of quantum mechanics, and particular aspects of measurement theory. Assuming only a background of standard quantum mechanics and electromagnetic theory, and containing many problems and references, this book will be invaluable to graduate students of quantum optics, as well as to researchers in this field.

  18. Anomalously slow spin dynamics and short-range correlations in the quantum spin ice systems Yb2Ti2O7 and Yb2Sn2O7

    NASA Astrophysics Data System (ADS)

    Maisuradze, A.; Dalmas de Réotier, P.; Yaouanc, A.; Forget, A.; Baines, C.; King, P. J. C.

    2015-09-01

    We report a positive muon spin relaxation and rotation (μ SR ) study of the quantum spin ice materials Yb2Ti2O7 and Yb2Sn2O7 focusing on the low field response. In agreement with earlier reports, data recorded in small longitudinal fields evidence anomalously slow spin dynamics in the microsecond range below the temperature Tc at which the specific heat displays an intense peak, namely Tc=0.24 K and 0.15 K, respectively, for the two systems. We found that slow dynamics extends above Tc up to at least 0.7 K for both compounds. The conventional dynamical Gaussian Kubo-Toyabe model describes the μ SR spectra recorded above Tc. At lower temperatures a published analytical extension of the Gaussian Kubo-Toyabe model provides a good description, consistent with the existence of short-range magnetic correlations. While the physical response of the two systems is qualitatively the same, Yb2Ti2O7 exhibits a much larger local magnetic susceptibility than Yb2Sn2O7 below Tc. Considering previously reported ac susceptibility, neutron scattering, and μ SR results, we suggest the existence of anomalously slow spin dynamics to be a common physical property of pyrochlore magnetic materials. The possibility of molecular spin substructures to be associated to the slow dynamics and therefore the short-range correlations is mentioned. The slow spin dynamics observed under field does not exclude the presence of much faster dynamics detected in extremely low or zero field.

  19. Improvement of thermal effects to rabbit atherosclerotic aortas by macro pulse irradiation of a quantum cascade laser in the 5.7 μm wavelength range

    NASA Astrophysics Data System (ADS)

    Hashimura, Keisuke; Ishii, Katsunori; Awazu, Kunio

    2015-03-01

    Atherosclerotic plaques mainly consist of cholesteryl esters. Cholesteryl esters have an absorption peak at the wavelength of 5.75 μm originated from C=O stretching vibration mode of ester bond. Our group achieved making cutting difference between atherosclerotic lesions and normal vessels using a quantum cascade laser (QCL) in the 5.7 μm wavelength range. QCLs are relatively new types of semiconductor lasers that can emit mid-infrared range. They are sufficiently compact and have recently achieved their high-power emission. However, large thermal damage was observed because the QCL worked as a quasi-continuous wave laser due to its short pulse interval. To realize less invasive ablation by the QCL, reducing thermal effects to normal vessels is needed. In this study, we tried improving the thermal effects by changing the pulse structure. First, irradiation effects to rabbit atherosclerotic aortas by macro pulse irradiation (irradiation of pulses at intervals) and conventional continuous pulse irradiation were compared. The macro pulse width and the macro pulse interval were set to 0.54 and 12 ms, respectively, because the thermal relaxation time of rabbit normal and atherosclerotic aortas in the oscillation wavelength was 0.54-12 ms. As a result, ablation depth became longer and coagulation width became shorter by the macro pulse irradiation. In addition, cutting difference between rabbit normal and atherosclerotic aortas was observed by the macro pulse irradiation. Therefore, the macro pulse irradiation achieved the improvement of thermal effects by the QCL in the 5.7 μm wavelength range. The QCL has the potential of realizing less-invasive laser angioplasty.

  20. Quantum Complexity in Graphene

    NASA Astrophysics Data System (ADS)

    Baskaran, G.

    Carbon has a unique position among elements in the periodic table. It produces an allotrope, graphene, a mechanically robust two dimensional semimetal. The multifarious properties that graphene exhibits has few parallels among elemental metals. From simplicity, namely carbon atoms connected by pure sp2 bonds, a wealth of novel quantum properties emerge. In classical complex systems such as a spin glass or a finance market, several competing agents or elements are responsible for unanticipated and difficult to predict emergent properties. The complex (sic) structure of quantum mechanics is responsbile for an unanticipated set of emergent properties in graphene. We call this quantum complexity. In fact, most quantum systems, phenomena and modern quantum field theory could be viewed as examples of quantum complexity. After giving a brief introduction to the quantum complexity we focus on our own work, which indicates the breadth in the type of quantum phenomena that graphene could support. We review our theoretical suggestions of, (i) spin-1 collective mode in netural graphene, (ii) relativistic type of phenomena in crossed electric and magnetic fields, (iii) room temperature superconductivity in doped graphene and (iv) composite Fermi sea in neutral graphene in uniform magnetic field and (v) two-channel Kondo effect. Except for the relativistic type of phenomena, the rest depend in a fundamental way on a weak electron correlation that exists in the broad two-dimensional band of graphene.

  1. Notes on nonlocal projective measurements in relativistic systems

    SciTech Connect

    Lin, Shih-Yuin

    2014-12-15

    In quantum mechanical bipartite systems, naive extensions of von Neumann’s projective measurement to nonlocal variables can produce superluminal signals and thus violate causality. We analyze the projective quantum nondemolition state-verification in a two-spin system and see how the projection introduces nonlocality without entanglement. For the ideal measurements of “R-nonlocal” variables, we argue that causality violation can be resolved by introducing further restrictions on the post-measurement states, which makes the measurement “Q-nonlocal”. After we generalize these ideas to quantum mechanical harmonic oscillators, we look into the projective measurements of the particle number of a single mode or a wave-packet of a relativistic quantum field in Minkowski space. It turns out that the causality-violating terms in the expectation values of the local operators, generated either by the ideal measurement of the “R-nonlocal” variable or the quantum nondemolition verification of a Fock state, are all suppressed by the IR and UV cutoffs of the theory. Thus relativistic quantum field theories with such projective measurements are effectively causal.

  2. Relativistic interactions and realistic applications

    SciTech Connect

    Hoch, T.; Madland, D.; Manakos, P.; Mannel, T.; Nikolaus, B.A.; Strottman, D. |

    1992-12-31

    A four-fermion-coupling Lagrangian (relativistic Skyrme-type) interaction has been proposed for relativistic nuclear structure calculations. This interaction, which has the merit of simplicity, is from the outset tailored as an effective interaction for relativistic Hartree-Fock calculations. Various extensions of such a model are discussed and compared with Walecka`s meson-nucleon mean field approach. We also present results of the calculation of nuclear ground state properties with an extended (density dependent) version of the four fermion interaction in a relativistic Hartree-Fock approximation.

  3. Recent Progress in Quantum Hadrodynamics

    SciTech Connect

    John Dirk Walecka, Brian D. Serot

    1997-01-01

    Quantum hadrodynamics (QHD) is a framework for describing the nuclear many-body problem as a relativistic system of baryons and mesons. Motivation is given for the utility of such an approach and for the importance of basing it on a local, Lorentz-invariant lagrangian density. Calculations of nuclear matter and finite nuclei in both renormalizable and nonrenormalizable, effective QHD models are discussed. Connections are made between the effective and renormalizable models, as well as between relativistic mean-field theory and more sophisticated treatments. Recent work in QHD involving nuclear structure, electroweak interactions in nuclei, relativistic transport theory, nuclear matter under extreme conditions, and the evaluation of loop diagrams is reviewed.

  4. Long-life relativistic electron enhancement events

    NASA Astrophysics Data System (ADS)

    Xiaochao, Y.

    2012-12-01

    Chinese 'Fengyun-1' series are low earth orbit satellites, the Space Particle Component Detector on 'Fengyun-1' have detected continuously relativistic electrons at the low earth orbit for a long time, obtained plenty of observations. From July, 2004 to February, 2005 'Fengyun-1'observed two strong relativistic electron enhancement (REE) events lasting a long time. These two events were all very intense, electron fluxes enhanced more than 3 orders of magnitude. And they all lasted a long time, are all rarely long-life events, the 'lifetime' of electrons during these two events are 24 and 23 days individually. The enhancement extent of electron fluxes is varied at different L-positions. In order to seek causes of these special events and the acceleration mechanism driving them, we investigate the simultaneous interplanetary and magnetospheric environments. Then it is found: before or on commencements of these two events, interplanetary and magnetospheric environments disturbed intensively, Dst index disturbed continuously for three times; evident southward interplanetary magnetic field and strong substorm activities are important factors to drive relativistic electrons enhancement dramatically, the substorm activities produced copious quantities of energetic electrons in the energy range 100~300keV, and provided an important seed population of energetic electrons needed for major relativistic electron events; frequently dynamic pressure fluctuations in the solar wind may be another key factor for these two extraordinary events, Fourier transforms of the solar wind dynamic pressure confirms that the pulsations occurred at several discrete frequencies about mHz, these fluctuations could lead to magnetospheric ULF pulsations at the same frequencies, and the mode numbers of these ULF pulsations were appropriate, then they could accelerated the 'seed' electrons to relativistic electrons effectively.

  5. Landau damping in relativistic plasmas

    NASA Astrophysics Data System (ADS)

    Young, Brent

    2016-02-01

    We examine the phenomenon of Landau damping in relativistic plasmas via a study of the relativistic Vlasov-Poisson (rVP) system on the torus for initial data sufficiently close to a spatially uniform steady state. We find that if the steady state is regular enough (essentially in a Gevrey class of degree in a specified range) and if the deviation of the initial data from this steady state is small enough in a certain norm, the evolution of the system is such that its spatial density approaches a uniform constant value quasi-exponentially fast (i.e., like exp ( - C |" separators=" t | ν ¯ ) for ν ¯ ∈ ( 0 , 1 ) ). We take as a priori assumptions that solutions launched by such initial data exist for all times (by no means guaranteed with rVP, but a reasonable assumption since we are close to a spatially uniform state) and that the various norms in question are continuous in time (which should be a consequence of an abstract version of the Cauchy-Kovalevskaya theorem). In addition, we must assume a kind of "reverse Poincaré inequality" on the Fourier transform of the solution. In spirit, this assumption amounts to the requirement that there exists 0 < ϰ < 1 so that the mass in the annulus ϰ ≤ |" separators=" v | < 1 for the solution launched by the initial data is uniformly small for all t. Typical velocity bounds for solutions to rVP launched by small initial data (at least on ℝ6) imply this bound. We note that none of our results require spherical symmetry (a crucial assumption for many current results on rVP).

  6. Selective ablation of atherosclerotic lesions with less thermal damage by controlling the pulse structure of a quantum cascade laser in the 5.7-µm wavelength range

    NASA Astrophysics Data System (ADS)

    Hashimura, Keisuke; Ishii, Katsunori; Awazu, Kunio

    2016-04-01

    Cholesteryl esters are the main components of atherosclerotic plaques, and they have an absorption peak at the wavelength of 5.75 µm. To realize less-invasive ablation of the atherosclerotic plaques using a quasi-continuous wave (quasi-CW) quantum cascade laser (QCL), the thermal effects on normal vessels must be reduced. In this study, we attempted to reduce the thermal effects by controlling the pulse structure. The irradiation effects on rabbit atherosclerotic aortas using macro pulse irradiation (irradiation of pulses at intervals) and conventional quasi-CW irradiation were compared. The macro pulse width and the macro pulse interval were determined based on the thermal relaxation time of atherosclerotic and normal aortas in the oscillation wavelength of the QCL. The ablation depth increased and the coagulation width decreased using macro pulse irradiation. Moreover, difference in ablation depth between the atherosclerotic and normal rabbit aortas using macro pulse irradiation was confirmed. Therefore, the QCL in the 5.7-µm wavelength range with controlling the pulse structure was effective for less-invasive laser angioplasty.

  7. Unraveling the differences of the hydrolytic activity of Trypanosoma cruzi trans-sialidase and Trypanosoma rangeli sialidase: a quantum mechanics-molecular mechanics modeling study.

    PubMed

    Bueren-Calabuig, Juan A; Pierdominici-Sottile, Gustavo; Roitberg, Adrian E

    2014-06-01

    Chagas' disease, also known as American trypanosomiasis, is a lethal, chronic disease that currently affects more than 10 million people in Central and South America. The trans-sialidase from Trypanosoma cruzi (T. cruzi, TcTS) is a crucial enzyme for the survival of this parasite: sialic acids from the host are transferred to the cell surface glycoproteins of the trypanosome, thereby evading the host's immune system. On the other hand, the sialidase of T. rangeli (TrSA), which shares 70% sequence identity with TcTS, is a strict hydrolase and shows no trans-sialidase activity. Therefore, TcTS and TrSA represent an excellent framework to understand how different catalytic activities can be achieved with extremely similar structures. By means of combined quantum mechanics-molecular mechanics (QM/MM, SCC-DFTB/Amberff99SB) calculations and umbrella sampling simulations, we investigated the hydrolysis mechanisms of TcTS and TrSA and computed the free energy profiles of these reactions. The results, together with our previous computational investigations, are able to explain the catalytic mechanism of sialidases and describe how subtle differences in the active site make TrSA a strict hydrolase and TcTS a more efficient trans-sialidase.

  8. Mimicking interacting relativistic theories with stationary pulses of light.

    PubMed

    Angelakis, Dimitris G; Huo, Ming-Xia; Chang, Darrick; Kwek, Leong Chuan; Korepin, Vladimir

    2013-03-01

    One of the most well known relativistic field theory models is the Thirring model. Its realization can demonstrate the famous prediction for the renormalization of mass due to interactions. However, experimental verification of the latter requires complex accelerator experiments whereas analytical solutions of the model can be extremely cumbersome to obtain. In this work, following Feynman's original proposal, we propose an alternative quantum system as a simulator of the Thirring model dynamics. Here, the relativistic particles are mimicked, counterintuitively, by polarized photons in a quantum nonlinear medium. We show that the entire set of regimes of the Thirring model--bosonic or fermionic, and massless or massive--can be faithfully reproduced using coherent light trapping techniques. The correlation functions of the model can be extracted by simple probing of the coherence functions of the output light using standard optical techniques.

  9. The relativist stance.

    PubMed

    Rössler, O E; Matsuno, K

    1998-04-01

    The two mindsets of absolutism and relativism are juxtaposed, and the relational or relativist stance is vindicated. The only 'absolute' entity which undeniably exists, consciousness has the reality of a dream. The escape hatch from this prison is relational, as Descartes and Levinas found out: Unfalsified relational consistency implies exteriority. Exteriority implies infinite power which in turn makes compassion inevitable. Aside from ethics as a royal way to enlightenment, a new technology called 'deep technology' may be accessible. It changes the whole world in a demonstrable fashion by manipulation of the micro frame--that is, the observer-world interface.

  10. The relativist stance.

    PubMed

    Rössler, O E; Matsuno, K

    1998-04-01

    The two mindsets of absolutism and relativism are juxtaposed, and the relational or relativist stance is vindicated. The only 'absolute' entity which undeniably exists, consciousness has the reality of a dream. The escape hatch from this prison is relational, as Descartes and Levinas found out: Unfalsified relational consistency implies exteriority. Exteriority implies infinite power which in turn makes compassion inevitable. Aside from ethics as a royal way to enlightenment, a new technology called 'deep technology' may be accessible. It changes the whole world in a demonstrable fashion by manipulation of the micro frame--that is, the observer-world interface. PMID:9648695

  11. Modeling relativistic nuclear collisions.

    SciTech Connect

    Anderlik, C.; Magas, V.; Strottman, D.; Csernai, L. P.

    2001-01-01

    Modeling Ultra-Relativistic Heavy Ion Collisioiis at RHIC and LHC energies using a Multi Module Model is presented. The first Module is the Effective String Rope Model for the calculation of the initial stages of the reaction; the output of this module is used as the initial state for the subsequent one-fluid hydrodynainical calculation module. It is shown that such an initial state leads to the creation of the third flow component. The hydrodynamical evolution of the energy density distribution is presented for RHIC energies. The final module describing the Freeze Out; and Hadronization is also discussed.

  12. Nonlinear waves and shocks in relativistic two-fluid hydrodynamics

    NASA Astrophysics Data System (ADS)

    Haim, L.; Gedalin, M.; Spitkovsky, A.; Krasnoselskikh, V.; Balikhin, M.

    2012-06-01

    Relativistic shocks are present in a number of objects where violent processes are accompanied by relativistic outflows of plasma. The magnetization parameter σ = B2/4πnmc2 of the ambient medium varies in wide range. Shocks with low σ are expected to substantially enhance the magnetic fields in the shock front. In non-relativistic shocks the magnetic compression is limited by nonlinear effects related to the deceleration of flow. Two-fluid analysis of perpendicular relativistic shocks shows that the nonlinearities are suppressed for σ<<1 and the magnetic field reaches nearly equipartition values when the magnetic energy density is of the order of the ion energy density, Beq2 ~ 4πnmic2γ. A large cross-shock potential eφ/mic2γ0 ~ B2/Beq2 develops across the electron-ion shock front. This potential is responsible for electron energization.

  13. Kernel functions and Baecklund transformations for relativistic Calogero-Moser and Toda systems

    SciTech Connect

    Hallnaes, Martin; Ruijsenaars, Simon

    2012-12-15

    We obtain kernel functions associated with the quantum relativistic Toda systems, both for the periodic version and for the nonperiodic version with its dual. This involves taking limits of previously known results concerning kernel functions for the elliptic and hyperbolic relativistic Calogero-Moser systems. We show that the special kernel functions at issue admit a limit that yields generating functions of Baecklund transformations for the classical relativistic Calogero-Moser and Toda systems. We also obtain the nonrelativistic counterparts of our results, which tie in with previous results in the literature.

  14. Relativistic Effects on Chemical Properties.

    ERIC Educational Resources Information Center

    McKelvey, Donald R.

    1983-01-01

    Discusses how anomalous chemical properties may be explained by considering relativistic effects. Traces development of the relativistic wave equation (Dirac equation) starting with the Borh treatment of the hydrogen atom and discusses major consequences of the Dirac equation. Suggests that these topics receive greater attention in the…

  15. relline: Relativistic line profiles calculation

    NASA Astrophysics Data System (ADS)

    Dauser, Thomas

    2015-05-01

    relline calculates relativistic line profiles; it is compatible with the common X-ray data analysis software XSPEC (ascl:9910.005) and ISIS (ascl:1302.002). The two basic forms are an additive line model (RELLINE) and a convolution model to calculate relativistic smearing (RELCONV).

  16. Relativistic and nonrelativistic quarkonium models

    SciTech Connect

    Ono, S.

    1982-11-01

    We propose a quarkonium potential for the Klein-Gordon equation. The relativistic effects are small even for uu-bar and dd-bar systems because the introduction of a scalar constant potential in a Klein-Gordon equation allows a minimization of relativistic effects via cancellations in our model.

  17. Stationary relativistic jets

    NASA Astrophysics Data System (ADS)

    Komissarov, Serguei S.; Porth, Oliver; Lyutikov, Maxim

    2015-11-01

    In this paper we describe a simple numerical approach which allows to study the structure of steady-state axisymmetric relativistic jets using one-dimensional time-dependent simulations. It is based on the fact that for narrow jets with vz≈ c the steady-state equations of relativistic magnetohydrodynamics can be accurately approximated by the one-dimensional time-dependent equations after the substitution z=ct. Since only the time-dependent codes are now publicly available this is a valuable and efficient alternative to the development of a high-specialised code for the time-independent equations. The approach is also much cheaper and more robust compared to the relaxation method. We tested this technique against numerical and analytical solutions found in literature as well as solutions we obtained using the relaxation method and found it sufficiently accurate. In the process, we discovered the reason for the failure of the self-similar analytical model of the jet reconfinement in relatively flat atmospheres and elucidated the nature of radial oscillations of steady-state jets.

  18. A relativistic trolley paradox

    NASA Astrophysics Data System (ADS)

    Matvejev, Vadim N.; Matvejev, Oleg V.; Grøn, Ø.

    2016-06-01

    We present an apparent paradox within the special theory of relativity, involving a trolley with relativistic velocity and its rolling wheels. Two solutions are given, both making clear the physical reality of the Lorentz contraction, and that the distance on the rails between each time a specific point on the rim touches the rail is not equal to 2 π R , where R is the radius of the wheel, but 2 π R / √{ 1 - R 2 Ω 2 / c 2 } , where Ω is the angular velocity of the wheels. In one solution, the wheel radius is constant as the velocity of the trolley increases, and in the other the wheels contract in the radial direction. We also explain two surprising facts. First that the shape of a rolling wheel is elliptical in spite of the fact that the upper part of the wheel moves faster than the lower part, and thus is more Lorentz contracted, and second that a Lorentz contracted wheel with relativistic velocity rolls out a larger distance between two successive touches of a point of the wheel on the rails than the length of a circle with the same radius as the wheels.

  19. Relativistic effects in astronomical timing measurements

    NASA Technical Reports Server (NTRS)

    Hellings, R. W.

    1986-01-01

    In this paper the relativistic transformations that are necessary to transform the results of earth-based astronomical timing observations from the terrestrial frame in which the observations are made to the proper frame of the astronomical object being observed are derived. Two coordinate systems are considered, the first being the parametrized post-Newtonian coordinate system and the second being a coordinate system based on the use of temps dynamique barycentrique as a time coordinate. Effects due to propagation of signals through curved spacetime and due to the relativistic gravitational time dilation for the earth are derived in each system. The results are then applied to three modern accurate data types spacecraft ranging, pulsar timing, and VLBI. A new effect is found in the analysis of VLBI data, amounting to a rescaling of VLBI-determined baselines produced by the curvature of space in the neighborhood of the sun.

  20. Relativistic fluid formulation and theory of intense relativistic electron beams

    SciTech Connect

    Siambis, J.G.

    1984-01-01

    A new general relativistic fluid formulation has been obtained for intense relativistic electron beams (IREB) with arbitrarily high relativistic mass factor ..gamma... This theory is valid for confined IREB equilibria such as those found inside high energy accelerators as well as in the pinched and ion-focused regimes of beam propagation in plasma channels. The new relativistic fluid formulation is based on the covariant relativistic fluid formulation of Newcomb with the parameter lambda identical to 1, in order to allow for realistic confined equilibria. The resulting equilibrium constraints require that the beam has a slow rotational velocity around its direction of propagation and that the off-diagonal thermal stress element, associated with these two directions of motion, be nonzero. The effective betatron oscillation frequency of the fluid elements of the beam is modified by the radial gradient and anisotropies in the thermal stress elements of the beam fluid. The wave equation, for sausage, hose and filamentation excitations on the relativistic fluid beam, is found to be formally identical to that obtained from the Vlasov equation approach, hence phase-mixing damping is a generic and self-consistent correlate of the new relativistic fluid formulation.

  1. Free Quantum Field Theory from Quantum Cellular Automata

    NASA Astrophysics Data System (ADS)

    Bisio, Alessandro; D'Ariano, Giacomo Mauro; Perinotti, Paolo; Tosini, Alessandro

    2015-10-01

    After leading to a new axiomatic derivation of quantum theory (see D'Ariano et al. in Found Phys, 2015), the new informational paradigm is entering the domain of quantum field theory, suggesting a quantum automata framework that can be regarded as an extension of quantum field theory to including an hypothetical Planck scale, and with the usual quantum field theory recovered in the relativistic limit of small wave-vectors. Being derived from simple principles (linearity, unitarity, locality, homogeneity, isotropy, and minimality of dimension), the automata theory is quantum ab-initio, and does not assume Lorentz covariance and mechanical notions. Being discrete it can describe localized states and measurements (unmanageable by quantum field theory), solving all the issues plaguing field theory originated from the continuum. These features make the theory an ideal framework for quantum gravity, with relativistic covariance and space-time emergent solely from the interactions, and not assumed a priori. The paper presents a synthetic derivation of the automata theory, showing how the principles lead to a description in terms of a quantum automaton over a Cayley graph of a group. Restricting to Abelian groups we show how the automata recover the Weyl, Dirac and Maxwell dynamics in the relativistic limit. We conclude with some new routes about the more general scenario of non-Abelian Cayley graphs. The phenomenology arising from the automata theory in the ultra-relativistic domain and the analysis of corresponding distorted Lorentz covariance is reviewed in Bisio et al. (Found Phys 2015, in this same issue).

  2. Gravimetry with Quantum Methods and Quantum Standards

    NASA Astrophysics Data System (ADS)

    Flury, J.

    2015-12-01

    Quantum metrology enables new methods for measuring gravitational quantities. Currently, significant progress in the development of quantum gravimeters, quantum optical clocks, and optical frequency transfer is underway. Quantum gravimeters use a variety of techniques to determine the gravity acceleration acting on clouds of atoms with coherent matter wave phase. We discuss configurations with very small and very large trajectories. Optical atomic clocks and optical frequency transfer allow the determination of gravity potential differences through the gravitational frequency redshift. Recent progress in clock development and in frequency transfer through optical fiber is leading to results with high relevance for geodesy. First experiments for long distance clock comparisons and chronometric leveling are underway. Concepts for geodetic modeling with relativistic quantities are being investigated.

  3. Geometric relativistic phase from Lorentz symmetry breaking effects in the cosmic string spacetime

    NASA Astrophysics Data System (ADS)

    Belich, H.; Bakke, K.

    2016-04-01

    In this paper, we have investigated the arising of geometric quantum phases in a relativistic quantum dynamics of a Dirac neutral particle from the spontaneous Lorentz symmetry violation effects in the cosmic string spacetime. We started by the Dirac equation in an effective metric, and we have observed a relativistic geometric phase which stems from the topology of the cosmic string spacetime and an intrinsic Lorentz symmetry breaking effects. It is shown that both Lorentz symmetry breaking effects and the topology of the defect yields a phase shift in the wave function of the nonrelativistic spin-1/2 particle.

  4. Some problems in relativistic thermodynamics

    SciTech Connect

    Veitsman, E. V.

    2007-11-15

    The relativistic equations of state for ideal and real gases, as well as for various interface regions, have been derived. These dependences help to eliminate some controversies in the relativistic thermodynamics based on the special theory of relativity. It is shown, in particular, that the temperature of system whose velocity tends to the velocity of light in vacuum varies in accordance with the Ott law T = T{sub 0}/{radical}1 - v{sup 2}/c{sup 2}. Relativistic dependences for heat and mass transfer, for Ohm's law, and for a viscous flow of a liquid have also been derived.

  5. General Relativistic Effects in Atom Interferometry

    SciTech Connect

    Dimopoulos, Savas; Graham, Peter W.; Hogan, Jason M.; Kasevich, Mark A.; /Stanford U., Phys. Dept.

    2008-03-17

    Atom interferometry is now reaching sufficient precision to motivate laboratory tests of general relativity. We begin by explaining the non-relativistic calculation of the phase shift in an atom interferometer and deriving its range of validity. From this we develop a method for calculating the phase shift in general relativity. This formalism is then used to find the relativistic effects in an atom interferometer in a weak gravitational field for application to laboratory tests of general relativity. The potentially testable relativistic effects include the non-linear three-graviton coupling, the gravity of kinetic energy, and the falling of light. We propose experiments, one currently under construction, that could provide a test of the principle of equivalence to 1 part in 10{sup 15} (300 times better than the present limit), and general relativity at the 10% level, with many potential future improvements. We also consider applications to other metrics including the Lense-Thirring effect, the expansion of the universe, and preferred frame and location effects.

  6. Efficient quantum walk on a quantum processor.

    PubMed

    Qiang, Xiaogang; Loke, Thomas; Montanaro, Ashley; Aungskunsiri, Kanin; Zhou, Xiaoqi; O'Brien, Jeremy L; Wang, Jingbo B; Matthews, Jonathan C F

    2016-01-01

    The random walk formalism is used across a wide range of applications, from modelling share prices to predicting population genetics. Likewise, quantum walks have shown much potential as a framework for developing new quantum algorithms. Here we present explicit efficient quantum circuits for implementing continuous-time quantum walks on the circulant class of graphs. These circuits allow us to sample from the output probability distributions of quantum walks on circulant graphs efficiently. We also show that solving the same sampling problem for arbitrary circulant quantum circuits is intractable for a classical computer, assuming conjectures from computational complexity theory. This is a new link between continuous-time quantum walks and computational complexity theory and it indicates a family of tasks that could ultimately demonstrate quantum supremacy over classical computers. As a proof of principle, we experimentally implement the proposed quantum circuit on an example circulant graph using a two-qubit photonics quantum processor. PMID:27146471

  7. Efficient quantum walk on a quantum processor

    NASA Astrophysics Data System (ADS)

    Qiang, Xiaogang; Loke, Thomas; Montanaro, Ashley; Aungskunsiri, Kanin; Zhou, Xiaoqi; O'Brien, Jeremy L.; Wang, Jingbo B.; Matthews, Jonathan C. F.

    2016-05-01

    The random walk formalism is used across a wide range of applications, from modelling share prices to predicting population genetics. Likewise, quantum walks have shown much potential as a framework for developing new quantum algorithms. Here we present explicit efficient quantum circuits for implementing continuous-time quantum walks on the circulant class of graphs. These circuits allow us to sample from the output probability distributions of quantum walks on circulant graphs efficiently. We also show that solving the same sampling problem for arbitrary circulant quantum circuits is intractable for a classical computer, assuming conjectures from computational complexity theory. This is a new link between continuous-time quantum walks and computational complexity theory and it indicates a family of tasks that could ultimately demonstrate quantum supremacy over classical computers. As a proof of principle, we experimentally implement the proposed quantum circuit on an example circulant graph using a two-qubit photonics quantum processor.

  8. Efficient quantum walk on a quantum processor.

    PubMed

    Qiang, Xiaogang; Loke, Thomas; Montanaro, Ashley; Aungskunsiri, Kanin; Zhou, Xiaoqi; O'Brien, Jeremy L; Wang, Jingbo B; Matthews, Jonathan C F

    2016-05-05

    The random walk formalism is used across a wide range of applications, from modelling share prices to predicting population genetics. Likewise, quantum walks have shown much potential as a framework for developing new quantum algorithms. Here we present explicit efficient quantum circuits for implementing continuous-time quantum walks on the circulant class of graphs. These circuits allow us to sample from the output probability distributions of quantum walks on circulant graphs efficiently. We also show that solving the same sampling problem for arbitrary circulant quantum circuits is intractable for a classical computer, assuming conjectures from computational complexity theory. This is a new link between continuous-time quantum walks and computational complexity theory and it indicates a family of tasks that could ultimately demonstrate quantum supremacy over classical computers. As a proof of principle, we experimentally implement the proposed quantum circuit on an example circulant graph using a two-qubit photonics quantum processor.

  9. Efficient quantum walk on a quantum processor

    PubMed Central

    Qiang, Xiaogang; Loke, Thomas; Montanaro, Ashley; Aungskunsiri, Kanin; Zhou, Xiaoqi; O'Brien, Jeremy L.; Wang, Jingbo B.; Matthews, Jonathan C. F.

    2016-01-01

    The random walk formalism is used across a wide range of applications, from modelling share prices to predicting population genetics. Likewise, quantum walks have shown much potential as a framework for developing new quantum algorithms. Here we present explicit efficient quantum circuits for implementing continuous-time quantum walks on the circulant class of graphs. These circuits allow us to sample from the output probability distributions of quantum walks on circulant graphs efficiently. We also show that solving the same sampling problem for arbitrary circulant quantum circuits is intractable for a classical computer, assuming conjectures from computational complexity theory. This is a new link between continuous-time quantum walks and computational complexity theory and it indicates a family of tasks that could ultimately demonstrate quantum supremacy over classical computers. As a proof of principle, we experimentally implement the proposed quantum circuit on an example circulant graph using a two-qubit photonics quantum processor. PMID:27146471

  10. Relativistic spectra of bound fermions

    SciTech Connect

    Giachetti, Riccardo; Sorace, Emanuele

    2007-02-27

    A two fermion relativistic invariant wave equation is used for numerical calculations of the hyperfine shifts of the Positronium levels in a Breit interaction scheme. The results agree with known data up to the order {alpha}4.

  11. Simulating relativistic binaries with Whisky

    NASA Astrophysics Data System (ADS)

    Baiotti, L.

    We report about our first tests and results in simulating the last phase of the coalescence and the merger of binary relativistic stars. The simulations were performed using our code Whisky and mesh refinement through the Carpet driver.

  12. Relativistic Transformation of Solid Angle.

    ERIC Educational Resources Information Center

    McKinley, John M.

    1980-01-01

    Rederives the relativistic transformations of light intensity from compact sources (stars) to show where and how the transformation of a solid angle contributes. Discusses astrophysical and other applications of the transformations. (Author/CS)

  13. Conductivity of a relativistic plasma

    SciTech Connect

    Braams, B.J.; Karney, C.F.F.

    1989-03-01

    The collision operator for a relativistic plasma is reformulated in terms of an expansion in spherical harmonics. This formulation is used to calculate the electrical conductivity. 13 refs., 1 fig., 1 tab.

  14. Relativistic Hartree-Bogoliubov description of the halo nuclei

    SciTech Connect

    Meng, J.; Ring, P.

    1996-12-31

    Here the authors report the development of the relativistic Hartree-Bogoliubov theory in coordinate space. Pairing correlations are taken into account by both density dependent force of zero range and finite range Gogny force. As a primary application the relativistic HB theory is used to describe the chain of Lithium isotopes reaching from {sup 6}Li to {sup 11}Li. In contrast to earlier investigations within a relativistic mean field theory and a density dependent Hartree Fock theory, where the halo in {sup 11}Li could only be reproduced by an artificial shift of the 1p{sub 1/2} level close to the continuum limit, the halo is now reproduced in a self-consistent way without further modifications using the scattering of Cooper pairs to the 2s{sub 1/2} level in the continuum. Excellent agreement with recent experimental data is observed.

  15. The quantum mechanics of cosmology.

    NASA Astrophysics Data System (ADS)

    Hartle, James B.

    to the Quantum Mechanics of a Non-Relativistic Particle * Semiclassical Prediction in Quantum Cosmology * ACKNOWLEDGEMENTS * REFERENCES * APPENDIX: BUZZWORDS

  16. Composition in the Quantum World

    NASA Astrophysics Data System (ADS)

    Hall, Edward Jonathan

    This thesis presents a problem for the foundations of quantum mechanics. It arises from the way that theory describes the composition of larger systems in terms of smaller ones, and renders untenable a wide range of interpretations of quantum mechanics. That quantum mechanics is difficult to interpret is old news, given the well-known Measurement Problem. But the problem I raise is quite different, and in important respects more fundamental. In brief: The physical world exhibits mereological structure: physical objects have parts, which in turn have parts, and so on. A natural way to try to represent this structure is by means of a particle theory, according to which the physical world consists entirely enduring physical objects which themselves have no proper parts, but aggregates of which are, or compose, all physical objects. Elementary, non-relativistic quantum mechanics can be cast in this mold--at least, according to the usual expositions of that theory. But herein lies the problem: the standard attempt to give a systematic particle interpretation to elementary quantum mechanics results in nonsense, thanks to the well-established principle of Permutation Invariance, which constrains the quantum -mechanical description of systems containing identical particles. Specifically, it follows from the most minimal principles of a particle interpretation (much weaker than those needed to generate the Measurement Problem), together with Permutation Invariance, that systems identical in composition must have the same physical state. In other words, systems which merely have the same numbers of the same types of particles are therefore, at all times, perfect physical duplicates. This conclusion is absurd: e.g., it is quite plausible that some of those particles which compose my body make up a system identical in composition to some pepperoni pizza. Yet no part of me is a qualitative physical duplicate of any pepperoni pizza. Perhaps "you are what you eat" --but not in

  17. Minimal relativistic three-particle equations

    SciTech Connect

    Lindesay, J.

    1981-07-01

    A minimal self-consistent set of covariant and unitary three-particle equations is presented. Numerical results are obtained for three-particle bound states, elastic scattering and rearrangement of bound pairs with a third particle, and amplitudes for breakup into states of three free particles. The mathematical form of the three-particle bound state equations is explored; constraints are set upon the range of eigenvalues and number of eigenstates of these one parameter equations. The behavior of the number of eigenstates as the two-body binding energy decreases to zero in a covariant context generalizes results previously obtained non-relativistically by V. Efimov.

  18. Photovoltaic Detector Based on Type II Heterostructure with Deep AlSb/InAsSb/AlSb Quantum Well in the Active Region for the Mid-Infrared Spectral Range

    NASA Astrophysics Data System (ADS)

    Konovalov, G. G.; Mikhailova, M. P.; Andreev, I. A.; Moiseev, K. D.; Ivanov, E. V.; Mikhailov, M. Yu; Yakovlev, Yu P.

    2013-08-01

    Photodetectors for the spectral range 2-4 μm, based on an asymmetric type-II heterostructure p-InAs/AlSb/InAsSb/AlSb/(p, n)-GaSb with a single deep quantum well (QW) or three deep QWs at the heterointerface, have been grown by metal-organic vapor phase epitaxy and analysed. The transport, luminescent, photoelectric, current-voltage, and capacitance-voltage characteristics of these structures have been examined. A high-intensity positive and negative luminescence was observed in the spectral range 3-4 μm at high temperatures (300-400 K). The photosensitivity spectra were in the range 1.2-3.6 μm (T = 77 K). Large values of quantum efficiency (η = 0.6-0.7), responsivity (Sλ = 0.9-1.4 A·W1), and detectivity D*λ 3.5·1011 to 1010 cm·Hz1/2·W-1) were obtained at T = 77-200 K. The small capacitance of the structures (C = 1.5 pF at V = -1 V and T = 300 K) enabled an estimate of the response time of the photodetector at τ = 75 ps, which corresponds to a bandwidth of about 6 GHz. Photodetectors of this kind are promising for heterodyne detection of the emission of quantum-cascade lasers and IR spectroscopy.

  19. A numerical investigation of relativistic turbulence

    NASA Astrophysics Data System (ADS)

    Zrake, Jonathan J.

    We present a program of numerical simulations designed to investigate the fundamental properties and phenomenological consequences of relativistic hydrodynamic and magnetohydrodynamic (MHD) turbulence. For the hydrodynamic case, we simulate a relativistically warm gas in a cubic periodic domain continuously driven at large scales with Lorentz factor of about 3. We employ a fifth-order accurate conservative finite-difference scheme on a uniform mesh with resolution up to 20483. The power spectrum of four-velocity scales with the -5/3 power of the wave-number, although deviations from strict scale similarity are evident. A Lorentz-covariant generalization of the longitudinal structure function is introduced, and found to be consistent with existing intermittency models. One-point statistics of the density field Gammarho are approximately log-normal, with skewness toward low densities being well modeled by recent advances in the compressible turbulence literature. Fundamental properties of driven, trans-relativistic, trans-Alfvenic MHD turbulence are studied on uniform meshes up to $10243. Classical predictions from the non-relativistic turbulence literature, such as the scale dependence of anisotropy with respect to the local magnetic field, are verified to hold in trans-relativistic conditions. Detailed studies of the small-scale turbulent dynamo for the conditions of merging neutron star binaries have been conducted. The dynamo is studied at a range of resolutions between 163 and 10243, from the kinematic through non-linear and saturation phases. Good agreement is found with classical predictions of the kinematic phase, and comparisons are made with recent measurements of non-linear dynamo efficiency. We find that very robustly, seed fields are amplified to magnetar strength (4 x1016 Gauss) within the ˜1 ms merger time-scale over 1 km turbulent volumes. The global magnetic energy budget is controlled by the prevalence and vigor of the turbulent volumes, with

  20. Relativistic calculations of magnetic resonance parameters: background and some recent developments.

    PubMed

    Autschbach, Jochen

    2014-03-13

    This article outlines some basic concepts of relativistic quantum chemistry and recent developments of relativistic methods for the calculation of the molecular properties that define the basic parameters of magnetic resonance spectroscopic techniques, i.e. nuclear magnetic resonance shielding, indirect nuclear spin-spin coupling and electric field gradients (nuclear quadrupole coupling), as well as with electron paramagnetic resonance g-factors and electron-nucleus hyperfine coupling. Density functional theory (DFT) has been very successful in molecular property calculations, despite a number of problems related to approximations in the functionals. In particular, for heavy-element systems, the large electron count and the need for a relativistic treatment often render the application of correlated wave function ab initio methods impracticable. Selected applications of DFT in relativistic calculation of magnetic resonance parameters are reviewed.

  1. `Relativistic' corrections to the mass of a plucked guitar string

    NASA Astrophysics Data System (ADS)

    Kolodrubetz, Michael; Polkovnikov, Anatoli

    Quantum systems respond non-adiabaticity when parameters controlling them are ramped at a finite rate. If the parameters themselves are dynamical - for instance the position of a box that defines the boundary of a quantum field - the feedback of these excitations gives rise to effective Newtonian equations of motion for the parameter. For the age old problem of photons in a box, this correction gives rise to a mass proportional to the energy of the photons. We show that a similar correction arises for a classical guitar string plucked with energy E; moving clamps at the ends of the string requires inertial mass m = 2 E /cs2 , where cs is the speed of sound. This quasi-relativistic effect should be observable in freshman physics level experiments. We then comment on how these simple methods have been readily extended to treat problems such as ramps and quenches of strongly-interacting superconductors and dynamical trapping near a quantum critical point.

  2. Relativistic collapse dynamics and black hole information loss

    NASA Astrophysics Data System (ADS)

    Bedingham, Daniel; Modak, Sujoy K.; Sudarsky, Daniel

    2016-08-01

    We study a proposal for the resolution of the black hole information puzzle within the context of modified versions of quantum theory involving spontaneous reduction of the quantum state. The theories of this kind, which were developed in order to address the so-called measurement problem in quantum theory have, in the past, been framed in a nonrelativistic setting and in that form they were previously applied to the black hole information problem. Here, and for the first time, we show in a simple toy model, a treatment of the problem within a fully relativistic setting. We also discuss the issues that the present analysis leaves as open problems to be dealt with in future refinements of the present approach.

  3. Relativistic description of inclusive quasielastic proton-nucleus scattering with relativistic distorted-wave impulse approximation and random-phase approximation

    NASA Astrophysics Data System (ADS)

    van Niekerk, D. D.; van der Ventel, B. I. S.; Titus, N. P.; Hillhouse, G. C.

    2011-04-01

    We present a fully relativistic model for polarized inclusive quasielastic proton-nucleus scattering that includes relativistic distorted waves for the projectile and ejectile (RDWIA), as well as the relativistic random-phase approximation (RPA) applied to the target nucleus. Using a standard relativistic impulse approximation treatment of quasielastic scattering and a two-body Scalar, Pseudoscalar, Vector, Axial vector, Tensor (SPVAT) form of the current operator, it is shown how the behavior of the projectile/ejectile and target can be decoupled. Distortion effects are included via a full partial-wave expansion of the relativistic wave functions. Target correlations are included via the relativistic RPA applied to mean-field theory in quantum hadrodynamics. A number of novel analytical and numerical techniques are employed to aid in this highly nontrivial calculation. A baseline plane-wave calculation is performed for the reaction Ca40(p⃗,p⃗') at an energy of 500 MeV and an angle θc.m.=40°. Here it is found that the effect of isoscalar correlations is a quenching of the cross section that is expected to become more pronounced at lower energies or for higher-density targets. A RDWIA calculation shows additional reduction and if isoscalar target correlations are included this effect is enhanced.

  4. Relativistic description of inclusive quasielastic proton-nucleus scattering with relativistic distorted-wave impulse approximation and random-phase approximation

    SciTech Connect

    Niekerk, D. D. van; Ventel, B. I. S. van der; Titus, N. P.; Hillhouse, G. C.

    2011-04-15

    We present a fully relativistic model for polarized inclusive quasielastic proton-nucleus scattering that includes relativistic distorted waves for the projectile and ejectile (RDWIA), as well as the relativistic random-phase approximation (RPA) applied to the target nucleus. Using a standard relativistic impulse approximation treatment of quasielastic scattering and a two-body Scalar, Pseudoscalar, Vector, Axial vector, Tensor (SPVAT) form of the current operator, it is shown how the behavior of the projectile/ejectile and target can be decoupled. Distortion effects are included via a full partial-wave expansion of the relativistic wave functions. Target correlations are included via the relativistic RPA applied to mean-field theory in quantum hadrodynamics. A number of novel analytical and numerical techniques are employed to aid in this highly nontrivial calculation. A baseline plane-wave calculation is performed for the reaction {sup 40}Ca(p-vector,p-vector{sup '}) at an energy of 500 MeV and an angle {theta}{sub c.m.}=40 deg. Here it is found that the effect of isoscalar correlations is a quenching of the cross section that is expected to become more pronounced at lower energies or for higher-density targets. A RDWIA calculation shows additional reduction and if isoscalar target correlations are included this effect is enhanced.

  5. Relativistic astrophysics - The view from Texas in Baltimore /Review/

    NASA Technical Reports Server (NTRS)

    Trimble, V. L.; Maran, S. P.

    1981-01-01

    Recent observational and theoretical work presented at the Tenth Texas Symposium on Relativistic Astrophysics held in Baltimore, Maryland from December 15-19, 1980, is outlined. Areas covered include the theoretical foundations of relativistic astrophysics in general relativity, quantum gravitational theory and the association of grand unification with astronomical and cosmological issues, the cosmic microwave, X-ray, gamma-ray, UV, cosmic ray and gravitational wave backgrounds, the current expansion rate and average mass-energy density of the universe, and mechanisms of galaxy formation. Also discussed are the characteristics of active galaxies and clusters emitting in the gamma-ray and X-ray regions, and compact objects formed from supernova explosions, including pulsars, X-ray-emitting neutron stars, Sco X-1 and SS 433, gamma-ray sources, and X-ray and gamma-ray bursters.

  6. On pseudosupersymmetric oscillators and reality of relativistic energies for vector mesons

    NASA Technical Reports Server (NTRS)

    Beckers, Jules; Debergh, Nathalie

    1995-01-01

    Specific oscillators - hereafter called pseudosupersymmetric oscillators - appear as interesting nonrelativistic concepts in connection with the study of relativistic vector mesons interacting with an external constant magnetic field when the real character of the energy eigenvalues is required as expected. A new pseudosupersymmetric quantum mechanics can then be developed and the corresponding pseudosupersymmetries can be pointed out.

  7. Causal Wave Propagation for Relativistic Massive Particles: Physical Asymptotics in Action

    ERIC Educational Resources Information Center

    Berry, M. V.

    2012-01-01

    Wavepackets representing relativistic quantum particles injected into a half-space, from a source that is switched on at a definite time, are represented by superpositions of plane waves that must include negative frequencies. Propagation is causal: it is a consequence of analyticity that at time t no part of the wave has travelled farther than…

  8. Introduction to the Quantum Theory of Elementary Cycles

    NASA Astrophysics Data System (ADS)

    Dolce, Donatello

    Elementary Cycles Theory (ECT) is a novel exact formulation of quantum-relativistic mechanics. Here, we present an introduction to its basic quantum aspects. On the one hand, Newton's law of inertia states that every isolated particle has persistent motion, i.e. constant energy and momentum. On the other hand, undulatory mechanics associates, by means of the Planck constant, a recurrence in time and space to the energy and the momentum of an elementary particle, respectively. Paraphrasing these two fundamental principles of modern physics, ECT postulates that every elementary constituent of nature (every elementary particle) is characterized by persistent intrinsic periodicity (as long it does not interact) whose space-time duration determines its kinematical state (energy and momentum). In other words, undulatory mechanics is imposed as constraint "overdetermining" relativistic mechanics, with fundamental motivations on Einstein's proposal of unification of quantum and relativistic theories. Every free particle is a (de Broglie) "periodic phenomenon" which can also be regarded as a reference clock and every system is decomposable in modulated elementary cycles. Indeed, ECT introduces a cyclic nature to the ordinary relativistic space-time coordinates. The resulting classical-relativistic mechanics turns out to be fully consistent with relativity and, at the same time, reproduces exactly all the fundamental aspects of ordinary quantum-relativistic mechanics (without any explicit quantisation). Relativity only fixes the differential structure of space-time without giving any prescription about the boundary of space-time, and the constraint of covariant periodicity (or similar relativistic boundary conditions) is allowed by the variational principle for relativistic theories. The constraint of intrinsic periodicity enforces the local nature of relativistic space-time and the wave-particle duality. Besides such unified description of relativistic and quantum dynamics

  9. Relativistic breakdown in planetary atmospheres

    SciTech Connect

    Dwyer, J. R.

    2007-04-15

    In 2003, a new electrical breakdown mechanism involving the production of runaway avalanches by positive feedback from runaway positrons and energetic photons was introduced. This mechanism, which shall be referred to as 'relativistic feedback', allows runaway discharges in gases to become self-sustaining, dramatically increasing the flux of runaway electrons, the accompanying high-energy radiation, and resulting ionization. Using detailed Monte Carlo calculations, properties of relativistic feedback are investigated. It is found that once relativistic feedback fully commences, electrical breakdown will occur and the ambient electric field, extending over cubic kilometers, will be discharged in as little as 2x10{sup -5} s. Furthermore, it is found that the flux of energetic electrons and x rays generated by this mechanism can exceed the flux generated by the standard relativistic runaway electron model by a factor of 10{sup 13}, making relativistic feedback a good candidate for explaining terrestrial gamma-ray flashes and other high-energy phenomena observed in the Earth's atmosphere.

  10. Intermediate quantum statistics for identical objects

    SciTech Connect

    Kuryshkin, V.V.

    1988-11-01

    Methods to construct various algebras of creation and annihilation operators of physical objects in complex quantum state spaces with a nonnegative metric are proposed. All allowed algebras for the cases of identical nonrelativistic systems in the second quantization of the Schrodinger equation, of identical quanta of relativistic tensor fields, and of identical quanta of relativistic spinor fields are constructed. A comparison of the obtained algebras with the well-known algebras of this type (Fermi, Bose, para-Fermi, and superalgebras) is given.

  11. Quantum probabilities from quantum entanglement: experimentally unpacking the Born rule

    NASA Astrophysics Data System (ADS)

    Harris, Jérémie; Bouchard, Frédéric; Santamato, Enrico; Zurek, Wojciech H.; Boyd, Robert W.; Karimi, Ebrahim

    2016-05-01

    The Born rule, a foundational axiom used to deduce probabilities of events from wavefunctions, is indispensable in the everyday practice of quantum physics. It is also key in the quest to reconcile the ostensibly inconsistent laws of the quantum and classical realms, as it confers physical significance to reduced density matrices, the essential tools of decoherence theory. Following Bohr’s Copenhagen interpretation, textbooks postulate the Born rule outright. However, recent attempts to derive it from other quantum principles have been successful, holding promise for simplifying and clarifying the quantum foundational bedrock. A major family of derivations is based on envariance, a recently discovered symmetry of entangled quantum states. Here, we identify and experimentally test three premises central to these envariance-based derivations, thus demonstrating, in the microworld, the symmetries from which the Born rule is derived. Further, we demonstrate envariance in a purely local quantum system, showing its independence from relativistic causality.

  12. Quantum probabilities from quantum entanglement: experimentally unpacking the Born rule

    DOE PAGES

    Harris, Jérémie; Bouchard, Frédéric; Santamato, Enrico; Zurek, Wojciech H.; Boyd, Robert W.; Karimi, Ebrahim

    2016-05-11

    The Born rule, a foundational axiom used to deduce probabilities of events from wavefunctions, is indispensable in the everyday practice of quantum physics. It is also key in the quest to reconcile the ostensibly inconsistent laws of the quantum and classical realms, as it confers physical significance to reduced density matrices, the essential tools of decoherence theory. Following Bohr's Copenhagen interpretation, textbooks postulate the Born rule outright. But, recent attempts to derive it from other quantum principles have been successful, holding promise for simplifying and clarifying the quantum foundational bedrock. Moreover, a major family of derivations is based on envariance,more » a recently discovered symmetry of entangled quantum states. Here, we identify and experimentally test three premises central to these envariance-based derivations, thus demonstrating, in the microworld, the symmetries from which the Born rule is derived. Furthermore, we demonstrate envariance in a purely local quantum system, showing its independence from relativistic causality.« less

  13. Frontiers in Relativistic Celestial Mechanics, Vol. 1. Theory

    NASA Astrophysics Data System (ADS)

    Kopeikin, Sergei

    2014-10-01

    Relativistic celestial mechanics - investigating the motion celestial bodies under the influence of general relativity - is a major tool of modern experimental gravitational physics. With a wide range of prominent authors from the field, this two-volume series consists of reviews on a multitude of advanced topics in the area of relativistic celestial mechanics - starting from more classical topics such as the regime of asymptotically-flat spacetime, light propagation and celestial ephemerides, but also including its role in cosmology and alternative theories of gravity as well as modern experiments in this area. This first volume of a two-volume series is concerned with theoretical foundations such as post-Newtonian solutions to the two-body problem, light propagation through time-dependent gravitational fields, as well as cosmological effects on the movement of bodies in the solar systems. On the occasion of his 80-th birthday, these two volumes honor V. A. Brumberg - one of the pioneers in modern relativistic celestial mechanics. Contributions include: M. Soffel: On the DSX-framework T. Damour: The general relativistic two body problem G. Schaefer: Hamiltonian dynamics of spinning compact binaries through high post-Newtonian approximations A. Petrov and S. Kopeikin: Post-Newtonian approximations in cosmology T. Futamase: On the backreaction problem in cosmology Y. Xie and S. Kopeikin: Covariant theory of the post-Newtonian equations of motion of extended bodies S. Kopeikin and P. Korobkov: General relativistic theory of light propagation in multipolar gravitational fields

  14. Properties of Doubly Heavy Baryons in the Relativistic Quark Model

    SciTech Connect

    Ebert, D.; Faustov, R.N.; Galkin, V.O.; Martynenko, A.P.

    2005-05-01

    Mass spectra and semileptonic decay rates of baryons consisting of two heavy (b or c) and one light quark are calculated in the framework of the relativistic quark model. The doubly heavy baryons are treated in the quark-diquark approximation. The ground and excited states of both the diquark and quark-diquark bound systems are considered. The quark-diquark potential is constructed. The light quark is treated completely relativistically, while the expansion in the inverse heavy-quark mass is used. The weak transition amplitudes of heavy diquarks bb and bc going, respectively, to bc and cc are explicitly expressed through the overlap integrals of the diquark wave functions in the whole accessible kinematic range. The relativistic baryon wave functions of the quark-diquark bound system are used for the calculation of the decay matrix elements, the Isgur-Wise function, and decay rates in the heavy-quark limit.

  15. Long range coherence in free electron lasers

    NASA Technical Reports Server (NTRS)

    Colson, W. B.

    1984-01-01

    The simple free electron laser (FEL) design uses a static, periodic, transverse magnetic field to undulate relativistic electrons traveling along its axis. This allows coupling to a co-propagating optical wave and results in bunching to produce coherent radiation. The advantages of the FEL are continuous tunability, operation at wavelengths ranging from centimeters to angstroms, and high efficiency resulting from the fact that the interaction region only contains light, relativistic electrons, and a magnetic field. Theoretical concepts and operational principles are discussed.

  16. Remote State Preparation for Quantum Fields

    NASA Astrophysics Data System (ADS)

    Ber, Ran; Zohar, Erez

    2016-07-01

    Remote state preparation is generation of a desired state by a remote observer. In spite of causality, it is well known, according to the Reeh-Schlieder theorem, that it is possible for relativistic quantum field theories, and a "physical" process achieving this task, involving superoscillatory functions, has recently been introduced. In this work we deal with non-relativistic fields, and show that remote state preparation is also possible for them, hence obtaining a Reeh-Schlieder-like result for general fields. Interestingly, in the nonrelativistic case, the process may rely on completely different resources than the ones used in the relativistic case.

  17. Smooth relativistic two-body propagators

    NASA Astrophysics Data System (ADS)

    Cooper, E. D.; Jennings, B. K.

    1988-06-01

    In this paper we develop two-body propagators for use in relativistic systems. The starting point is the observation of Thies that the success of the Dirac approach may be attributed to the cancellation of short-range structure generated by the iteration of a momentum dependent potential in the Lippmann-Schwinger equation. We elevate this observation to a principle and look for two-body propagators that have as little short-range structure as possible. The propagators so found treat the two particles symmetrically, reduce to the correct relativistic equation when either one of the two particles becomes very massive and have the correct contribution from the two-body cut. For the pi-nucleon system we find that both the soft-pion theorems and unitarity can be easily satisfied. For proton-nucleus or electron-nucleus scattering we get a simple method of including nuclear recoil. The present approach generates propagators similar to those of Todorov and of Crater and Van Alstine.

  18. Fluctuations in relativistic causal hydrodynamics

    NASA Astrophysics Data System (ADS)

    Kumar, Avdhesh; Bhatt, Jitesh R.; Mishra, Ananta P.

    2014-05-01

    Formalism to calculate the hydrodynamic fluctuations by applying the Onsager theory to the relativistic Navier-Stokes equation is already known. In this work, we calculate hydrodynamic fluctuations within the framework of the second order hydrodynamics of Müller, Israel and Stewart and its generalization to the third order. We have also calculated the fluctuations for several other causal hydrodynamical equations. We show that the form for the Onsager-coefficients and form of the correlation functions remain the same as those obtained by the relativistic Navier-Stokes equation and do not depend on any specific model of hydrodynamics. Further we numerically investigate evolution of the correlation function using the one dimensional boost-invariant (Bjorken) flow. We compare the correlation functions obtained using the causal hydrodynamics with the correlation function for the relativistic Navier-Stokes equation. We find that the qualitative behavior of the correlation functions remains the same for all the models of the causal hydrodynamics.

  19. Toward a relativistic gas dynamics

    SciTech Connect

    Solovev, L.S.

    1982-01-01

    Macroscopic gas dynamics on the basis of general-relativity equations is examined. An additional equation is derived which provides for completeness of the system of relativistic gasdynamic equations. Relativistic equations of two-fluid electromagnetic gas dynamics are obtained. The introduction of appropriate energy-momentum tensors makes it possible to allow for dissipative processes conditioned by viscosity, thermal conductivity, radiative thermal conductivity, ohmic resistance, and ion-electron temperature difference. The problem of generalizing the Friedmann cosmological model in the case of particle production and annihilation is considered. Also, considered are gas equilibrium in a spherically symmetric gravitational field and a two-fluid relativistic stream in an intrinsic electromagnetic field. 16 references.

  20. WKB analysis of relativistic Stern-Gerlach measurements

    NASA Astrophysics Data System (ADS)

    Palmer, Matthew C.; Takahashi, Maki; Westman, Hans F.

    2013-09-01

    Spin is an important quantum degree of freedom in relativistic quantum information theory. This paper provides a first-principles derivation of the observable corresponding to a Stern-Gerlach measurement with relativistic particle velocity. The specific mathematical form of the Stern-Gerlach operator is established using the transformation properties of the electromagnetic field. To confirm that this is indeed the correct operator we provide a detailed analysis of the Stern-Gerlach measurement process. We do this by applying a WKB approximation to the minimally coupled Dirac equation describing an interaction between a massive fermion and an electromagnetic field. Making use of the superposition principle we show that the +1 and -1 spin eigenstates of the proposed spin operator are split into separate packets due to the inhomogeneity of the Stern-Gerlach magnetic field. The operator we obtain is dependent on the momentum between particle and Stern-Gerlach apparatus, and is mathematically distinct from two other commonly used operators. The consequences for quantum tomography are considered.

  1. Doppler factors in satellite-to-satellite tracking. [with relativistic effects

    NASA Technical Reports Server (NTRS)

    Marini, J. W.

    1974-01-01

    The Doppler factors occurring in range rate satellite-to-satellite tracking measurements are derived with special relativistic effects included. The error resulting from the use of simplified expressions for these factors is discussed.

  2. Correction to the Alfven-Lawson criterion for relativistic electron beams

    SciTech Connect

    Dodin, I. Y.; Fisch, N. J.

    2006-10-15

    The Alfven-Lawson criterion for relativistic electron beams is revised. The parameter range is found, in which a stationary beam can carry arbitrarily large current, regardless of its transverse structure.

  3. Phenomenological Relativistic Energy Density Functionals

    SciTech Connect

    Lalazissis, G. A.; Kartzikos, S.; Niksic, T.; Paar, N.; Vretenar, D.; Ring, P.

    2009-08-26

    The framework of relativistic nuclear energy density functionals is applied to the description of a variety of nuclear structure phenomena, not only in spherical and deformed nuclei along the valley of beta-stability, but also in exotic systems with extreme isospin values and close to the particle drip-lines. Dynamical aspects of exotic nuclear structure is explored using the fully consistent quasiparticle random-phase approximation based on the relativistic Hartree-Bogoliubov model. Recent applications of energy density functionals with explicit density dependence of the meson-nucleon couplings are presented.

  4. Relativistic three-partite non-locality

    NASA Astrophysics Data System (ADS)

    Moradpour, Hooman; Montakhab, Afshin

    2016-05-01

    Bell-like inequalities have been used in order to distinguish non-local quantum pure states by various authors. The behavior of such inequalities under Lorentz transformation (LT) has been a source of debate and controversies in the past. In this paper, we consider the two most commonly studied three-particle pure states, that of W and Greenberger-Horne-Zeilinger (GHZ) states which exhibit distinctly different types of entanglement. We discuss the various types of three-particle inequalities used in previous studies and point to their corresponding shortcomings and strengths. Our main result is that if one uses Czachor’s relativistic spin operator and Svetlichny’s inequality as the main measure of non-locality and uses the same angles in the rest frame (S) as well as the moving frame (S‧), then maximally violated inequality in S will decrease in the moving frame, and will eventually lead to lack of non-locality (i.e. satisfaction of inequality) in the v→c limit. This is shown for both the GHZ and W states and in two different configurations which are commonly studied (Cases 1 and 2). Our results are in line with a more familiar case of two particle case. We also show that the satisfaction of Svetlichny’s inequality in the v→c limit is independent of initial particles’ velocity. Our study shows that whenever we use Czachor’s relativistic spin operator, results draws a clear picture of three-particle non-locality making its general properties consistent with previous studies on two-particle systems regardless of the W state or the GHZ state is involved. Throughout the paper, we also address the results of using Pauli’s operator in investigating the behavior of |Sv| under LT for both of the GHZ and W states and two cases (Cases 1 and 2). Our investigation shows that the violation of |Sv| in moving frame depends on the particle’s energy in the lab frame, which is in agreement with some previous works on two and three-particle systems. Our work may

  5. Spacetime and Quantum Propagation From Digital Clocks

    NASA Astrophysics Data System (ADS)

    Ord, Garnet. N.

    2013-09-01

    Minkowski spacetime predates quantum mechanics and is frequently regarded as an extension of the classical paradigm of Newtonian physics, rather than a harbinger of quantum mechanics. By inspecting how discrete clocks operate in a relativistic world we show that this view is misleading. Discrete relativistic clocks implicate classical spacetime provided a continuum limit is taken in such a way that successive ticks of the clock yield a smooth worldline. The classical picture emerges but does so by confining unitary propagation into spacetime regions between ticks that have zero area in the continuum limit. Clocks allowed a continuum limit that does not force inter-event intervals to zero, satisfy the Dirac equation. This strongly suggests that the origin of quantum propagation is to be found in the shift from Newton's absolute time to Minkowski's frame dependent time and is ultimately relativistic in origin.

  6. Relativistic Hydrodynamics for Heavy-Ion Collisions

    ERIC Educational Resources Information Center

    Ollitrault, Jean-Yves

    2008-01-01

    Relativistic hydrodynamics is essential to our current understanding of nucleus-nucleus collisions at ultrarelativistic energies (current experiments at the Relativistic Heavy Ion Collider, forthcoming experiments at the CERN Large Hadron Collider). This is an introduction to relativistic hydrodynamics for graduate students. It includes a detailed…

  7. Relativistic treatment of inertial spin effects

    NASA Astrophysics Data System (ADS)

    Ryder, Lewis

    1998-03-01

    A relativistic spin operator for Dirac particles is identified and it is shown that a coupling of spin to angular velocity arises in the relativistic case, just as Mashhoon had speculated, and Hehl and Ni had demonstrated, in the non-relativistic case.

  8. Frontiers in Relativistic Celestial Mechanics, Vol. 2, Applications and Experiments

    NASA Astrophysics Data System (ADS)

    Kopeikin, Sergei

    2014-08-01

    Relativistic celestial mechanics - investigating the motion celestial bodies under the influence of general relativity - is a major tool of modern experimental gravitational physics. With a wide range of prominent authors from the field, this two-volume series consists of reviews on a multitude of advanced topics in the area of relativistic celestial mechanics - starting from more classical topics such as the regime of asymptotically-flat spacetime, light propagation and celestial ephemerides, but also including its role in cosmology and alternative theories of gravity as well as modern experiments in this area. This second volume of a two-volume series covers applications of the theory as well as experimental verifications. From tools to determine light travel times in curved space-time to laser ranging between earth and moon and between satellites, and impacts on the definition of time scales and clock comparison techniques, a variety of effects is discussed. On the occasion of his 80-th birthday, these two volumes honor V. A. Brumberg - one of the pioneers in modern relativistic celestial mechanics. Contributions include: J. Simon, A. Fienga: Victor Brumberg and the French school of analytical celestial mechanics T. Fukushima: Elliptic functions and elliptic integrals for celestial mechanics and dynamical astronomy P. Teyssandier: New tools for determining the light travel time in static, spherically symmetric spacetimes beyond the order G2 J. Müller, L. Biskupek, F. Hofmann and E. Mai: Lunar laser ranging and relativity N. Wex: Testing relativistic celestial mechanics with radio pulsars I. Ciufolini et al.: Dragging of inertial frames, fundamental physics, and satellite laser ranging G. Petit, P. Wolf, P. Delva: Atomic time, clocks, and clock comparisons in relativistic spacetime: a review

  9. Relativistic symmetries in nuclear single-particle spectra

    NASA Astrophysics Data System (ADS)

    Guo, Jian-You; Liang, Hao Zhao; Meng, Jie; Zhou, Shan-Gui

    Symmetry is a fundamental concept in quantum physics. The quasi-degeneracy between single-particle orbitals (n, l, j = l + 1/2) and (n -1, l + 2, j = l + 3/2) indicates a hidden symmetry in atomic nuclei, the so-called pseudospin symmetry. Since the pseudospin symmetry was recognized as a relativistic symmetry in 1990s, many special features, including the spin symmetry for anti-nucleons, and many new concepts have been introduced. In this Chapter, we will illustrate the schematic picture of spin and pseudospin symmetries, derive the basic formalism, highlight the recent progress from several different aspects, and discuss selected open issues in this topic.

  10. Relativistic Effects Break Periodicity in Group 6 Diatomic Molecules.

    PubMed

    Wang, Yi-Lei; Hu, Han-Shi; Li, Wan-Lu; Wei, Fan; Li, Jun

    2016-02-01

    The finding of the periodic law is a milestone in chemical science. The periodicity of light elements in the Periodic Table is fully accounted for by quantum mechanics. Here we report that relativistic effects change the bond multiplicity of the group 6 diatomic molecules M2 (M = Cr, Mo, W, Sg) from hextuple bonds for Cr2, Mo2, W2 to quadruple bonds for Sg2, thus breaking the periodicity in the nonrelativistic domain. The same trend is also found for other superheavy-element diatomics Rf2, Db2, Bh2, and Hs2.

  11. Relativistic Effects Break Periodicity in Group 6 Diatomic Molecules.

    PubMed

    Wang, Yi-Lei; Hu, Han-Shi; Li, Wan-Lu; Wei, Fan; Li, Jun

    2016-02-01

    The finding of the periodic law is a milestone in chemical science. The periodicity of light elements in the Periodic Table is fully accounted for by quantum mechanics. Here we report that relativistic effects change the bond multiplicity of the group 6 diatomic molecules M2 (M = Cr, Mo, W, Sg) from hextuple bonds for Cr2, Mo2, W2 to quadruple bonds for Sg2, thus breaking the periodicity in the nonrelativistic domain. The same trend is also found for other superheavy-element diatomics Rf2, Db2, Bh2, and Hs2. PMID:26787134

  12. Generalized relativistic wave equations with intrinsic maximum momentum

    NASA Astrophysics Data System (ADS)

    Ching, Chee Leong; Ng, Wei Khim

    2014-05-01

    We examine the nonperturbative effect of maximum momentum on the relativistic wave equations. In momentum representation, we obtain the exact eigen-energies and wave functions of one-dimensional Klein-Gordon and Dirac equation with linear confining potentials, and the Dirac oscillator. Bound state solutions are only possible when the strength of scalar potential is stronger than vector potential. The energy spectrum of the systems studied is bounded from above, whereby classical characteristics are observed in the uncertainties of position and momentum operators. Also, there is a truncation in the maximum number of bound states that is allowed. Some of these quantum-gravitational features may have future applications.

  13. Particle Acceleration in Relativistic Outflows

    NASA Technical Reports Server (NTRS)

    Bykov, Andrei; Gehrels, Neil; Krawczynski, Henric; Lemoine, Martin; Pelletier, Guy; Pohl, Martin

    2012-01-01

    In this review we confront the current theoretical understanding of particle acceleration at relativistic outflows with recent observational results on various source classes thought to involve such outflows, e.g. gamma-ray bursts, active galactic nuclei, and pulsar wind nebulae. We highlight the possible contributions of these sources to ultra-high-energy cosmic rays.

  14. Simplified Relativistic Force Transformation Equation.

    ERIC Educational Resources Information Center

    Stewart, Benjamin U.

    1979-01-01

    A simplified relativistic force transformation equation is derived and then used to obtain the equation for the electromagnetic forces on a charged particle, calculate the electromagnetic fields due to a point charge with constant velocity, transform electromagnetic fields in general, derive the Biot-Savart law, and relate it to Coulomb's law.…

  15. The He + H2+ --> HeH+ + H reaction: Ab initio studies of the potential energy surface, benchmark time-independent quantum dynamics in an extended energy range and comparison with experiments

    NASA Astrophysics Data System (ADS)

    De Fazio, Dario; de Castro-Vitores, Miguel; Aguado, Alfredo; Aquilanti, Vincenzo; Cavalli, Simonetta

    2012-12-01

    In this work we critically revise several aspects of previous ab initio quantum chemistry studies [P. Palmieri et al., Mol. Phys. 98, 1835 (2000);, 10.1080/00268970009483387 C. N. Ramachandran et al., Chem. Phys. Lett. 469, 26 (2009)], 10.1016/j.cplett.2008.12.035 of the HeH_2^+ system. New diatomic curves for the H_2^+ and HeH+ molecular ions, which provide vibrational frequencies at a near spectroscopic level of accuracy, have been generated to test the quality of the diatomic terms employed in the previous analytical fittings. The reliability of the global potential energy surfaces has also been tested performing benchmark quantum scattering calculations within the time-independent approach in an extended interval of energies. In particular, the total integral cross sections have been calculated in the total collision energy range 0.955-2.400 eV for the scattering of the He atom by the ortho- and para-hydrogen molecular ion. The energy profiles of the total integral cross sections for selected vibro-rotational states of H_2^+ (v = 0, …,5 and j = 1, …,7) show a strong rotational enhancement for the lower vibrational states which becomes weaker as the vibrational quantum number increases. Comparison with several available experimental data is presented and discussed.

  16. Fast lattice Boltzmann solver for relativistic hydrodynamics.

    PubMed

    Mendoza, M; Boghosian, B M; Herrmann, H J; Succi, S

    2010-07-01

    A lattice Boltzmann formulation for relativistic fluids is presented and numerically validated through quantitative comparison with recent hydrodynamic simulations of relativistic fluids. In order to illustrate its capability to handle complex geometries, the scheme is also applied to the case of a three-dimensional relativistic shock wave, generated by a supernova explosion, impacting on a massive interstellar cloud. This formulation opens up the possibility of exporting the proven advantages of lattice Boltzmann methods, namely, computational efficiency and easy handling of complex geometries, to the context of (mildly) relativistic fluid dynamics at large, from quark-gluon plasmas up to supernovae with relativistic outflows.

  17. Fast lattice Boltzmann solver for relativistic hydrodynamics.

    PubMed

    Mendoza, M; Boghosian, B M; Herrmann, H J; Succi, S

    2010-07-01

    A lattice Boltzmann formulation for relativistic fluids is presented and numerically validated through quantitative comparison with recent hydrodynamic simulations of relativistic fluids. In order to illustrate its capability to handle complex geometries, the scheme is also applied to the case of a three-dimensional relativistic shock wave, generated by a supernova explosion, impacting on a massive interstellar cloud. This formulation opens up the possibility of exporting the proven advantages of lattice Boltzmann methods, namely, computational efficiency and easy handling of complex geometries, to the context of (mildly) relativistic fluid dynamics at large, from quark-gluon plasmas up to supernovae with relativistic outflows. PMID:20867451

  18. Relativistic formulation of the Voigt profile

    NASA Astrophysics Data System (ADS)

    Wcisło, P.; Amodio, P.; Ciuryło, R.; Gianfrani, L.

    2015-02-01

    The relativistic formulation of the Voigt profile is reported for the spontaneous emission from an atomic or molecular cloud, in coincidence with a given spectral line. We considered the simultaneous occurrence of homogeneous broadening and thermal broadening, this latter being determined by the relativistic Doppler effect. Our formula for the relativistic Voigt profile reproduces those characterizing the two available limit cases, namely, the relativistic Gaussian profile and the classical Voigt convolution. The relativistic deformation of the Voigt profile was carefully quantified at different temperatures, in the case of the molecular hydrogen spectrum.

  19. Constraint algebra for interacting quantum systems

    NASA Astrophysics Data System (ADS)

    Fubini, S.; Roncadelli, M.

    1988-04-01

    We consider relativistic constrained systems interacting with external fields. We provide physical arguments to support the idea that the quantum constraint algebra should be the same as in the free quantum case. For systems with ordering ambiguities this principle is essential to obtain a unique quantization. This is shown explicitly in the case of a relativistic spinning particle, where our assumption about the constraint algebra plus invariance under general coordinate transformations leads to a unique S-matrix. On leave from Dipartimento di Fisica Nucleare e Teorica, Università di Pavia and INFN, I-27100 Pavia, Italy.

  20. Simulations of Relativistic Extragalactic Jets

    NASA Astrophysics Data System (ADS)

    Hughes, P. A.; Duncan, G. C.

    1994-05-01

    We present results for 2-D, axisymmetric simulations of flows with Lorentz factors ~ 5 -- 10, typical of values inferred for superluminal BL Lacs and QSOs. The simulations were performed with a numerical hydrodynamic code that admits relativistic flow speed. We exploit the property that the relativistic Euler equations for mass, momentum and total energy densities in the laboratory frame have the same form as the nonrelativistic equations, to solve for laboratory frame variables using a conventional Godunov-type scheme with approximate Riemann solver: the HLLE method. The relativistic nature of the flow is incorporated by performing a Lorentz transformation at every step, at each cell center or cell boundary where pressure, sound speed or velocity are required. Determination of the velocity in this manner is a robust algebraic procedure within which we can ensure that vrelativistic flows exhibit a less pronounced pattern of incident and reflection shocks on axis. For flows which have propagated to a fixed number of jet radii, the Kelvin-Helmholtz instability at the contact surface is much less evident in the high Lorentz factor cases, supporting the contention that relativistic flows are less prone to such instability. We describe how the morphology of the cocoon and shocked ambient gas change with increasing Lorentz factor. This work was supported by NSF grant AST 9120224 and by the Ohio Supercomputer Center from a Cray Research Software Development Grant.

  1. Colloidal Synthesis of Quantum Confined Single Crystal CsPbBr3 Nanosheets with Lateral Size Control up to the Micrometer Range

    PubMed Central

    2016-01-01

    We report the nontemplated colloidal synthesis of single crystal CsPbBr3 perovskite nanosheets with lateral sizes up to a few micrometers and with thickness of just a few unit cells (i.e., below 5 nm), hence in the strong quantum confinement regime, by introducing short ligands (octanoic acid and octylamine) in the synthesis together with longer ones (oleic acid and oleylamine). The lateral size is tunable by varying the ratio of shorter ligands over longer ligands, while the thickness is mainly unaffected by this parameter and stays practically constant at 3 nm in all the syntheses conducted at short-to-long ligands volumetric ratio below 0.67. Beyond this ratio, control over the thickness is lost and a multimodal thickness distribution is observed. PMID:27228475

  2. Colloidal Synthesis of Quantum Confined Single Crystal CsPbBr3 Nanosheets with Lateral Size Control up to the Micrometer Range.

    PubMed

    Shamsi, Javad; Dang, Zhiya; Bianchini, Paolo; Canale, Claudio; Stasio, Francesco Di; Brescia, Rosaria; Prato, Mirko; Manna, Liberato

    2016-06-15

    We report the nontemplated colloidal synthesis of single crystal CsPbBr3 perovskite nanosheets with lateral sizes up to a few micrometers and with thickness of just a few unit cells (i.e., below 5 nm), hence in the strong quantum confinement regime, by introducing short ligands (octanoic acid and octylamine) in the synthesis together with longer ones (oleic acid and oleylamine). The lateral size is tunable by varying the ratio of shorter ligands over longer ligands, while the thickness is mainly unaffected by this parameter and stays practically constant at 3 nm in all the syntheses conducted at short-to-long ligands volumetric ratio below 0.67. Beyond this ratio, control over the thickness is lost and a multimodal thickness distribution is observed.

  3. Quantum Fictitious Forces

    NASA Astrophysics Data System (ADS)

    Białynicki-Birula, I.; Cirone, M. A.; Dahl, J. P.; Seligman, T. H.; Straub, F.; Schleich, W. P.

    2003-09-01

    We present Heisenberg's equation of motion for the radial variable of a free non-relativistic particle in D dimensions. The resulting radial force consists of three contributions: (i) the quantum fictitious force which is either attractive or repulsive depending on the number of dimensions, (ii) a singular quantum force located at the origin, and (iii) the centrifugal force associated with non-vanishing angular momentum. Moreover, we use Heisenberg's uncertainty relation to introduce a lower bound for the kinetic energy of an ensemble of neutral particles. This bound is quadratic in the number of atoms and can be traced back to the repulsive quantum fictitious potential. All three forces arise for a free particle: “Force without force”.

  4. Relativistic Energy Density Functionals: beyond mean-field description of exotic structures

    SciTech Connect

    Vretenar, D.; Niksic, T.; Ring, P.; Lalazissis, G. A.

    2009-01-28

    The framework of relativistic energy density functionals is extended to include correlations related to the restoration of broken symmetries and to fluctuations of collective variables. The generator coordinate method is used to perform configuration mixing of angular-momentum and particle-number projected relativistic wave functions. This approach enables a quantitative description of the evolution of shell-structure, deformation and shape coexistence phenomena in nuclei with soft potential energy surfaces, and singular properties of excitation spectra and transition rates at critical points of quantum shape phase transitions.

  5. NUCLEAR CROSS-SECTION CALCULATIONS IN THE 1 MEV TO 5 GEV RANGE WITH COMBINED SEMI-CLASSICAL AND QUANTUM MECHANICAL MODELS

    SciTech Connect

    Guimaraes, F.B.

    2002-03-07

    In this work we describe neutron and proton induced reaction cross-sections for iron produced by the codes TNG and CEM95 in the 5 to 300 MeV energy range. TNG calculations cover the 5-90 MeV range, while CEM95 covers the 50-300 MeV high energy range. The two codes show some disagreements in the overlap energy range, both among themselves and with the experimental data, which are presently being addressed. The experimental data used are from NNDC and/or from LA150 NSE references. We also describe some developments for combining TNG and CEM95 into a new code called CETNG (Cascade Exciton TNG).

  6. Quantum work statistics of charged Dirac particles in time-dependent fields.

    PubMed

    Deffner, Sebastian; Saxena, Avadh

    2015-09-01

    The quantum Jarzynski equality is an important theorem of modern quantum thermodynamics. We show that the Jarzynski equality readily generalizes to relativistic quantum mechanics described by the Dirac equation. After establishing the conceptual framework we solve a pedagogical, yet experimentally relevant, system analytically. As a main result we obtain the exact quantum work distributions for charged particles traveling through a time-dependent vector potential evolving under Schrödinger as well as under Dirac dynamics, and for which the Jarzynski equality is verified. Special emphasis is put on the conceptual and technical subtleties arising from relativistic quantum mechanics.

  7. Quantum work statistics of charged Dirac particles in time-dependent fields

    SciTech Connect

    Deffner, Sebastian; Saxena, Avadh

    2015-09-28

    The quantum Jarzynski equality is an important theorem of modern quantum thermodynamics. We show that the Jarzynski equality readily generalizes to relativistic quantum mechanics described by the Dirac equation. After establishing the conceptual framework we solve a pedagogical, yet experimentally relevant, system analytically. As a main result we obtain the exact quantum work distributions for charged particles traveling through a time-dependent vector potential evolving under Schrödinger as well as under Dirac dynamics, and for which the Jarzynski equality is verified. Thus, special emphasis is put on the conceptual and technical subtleties arising from relativistic quantum mechanics.

  8. Neutral-atom electron binding energies from relaxed-orbital relativistic Hartree-Fock-Slater calculations for Z between 2 and 106

    NASA Technical Reports Server (NTRS)

    Huang, K.-N.; Aoyagi, M.; Mark, H.; Chen, M. H.; Crasemann, B.

    1976-01-01

    Electron binding energies in neutral atoms have been calculated relativistically, with the requirement of complete relaxation. Hartree-Fock-Slater wave functions served as zeroth-order eigenfunctions to compute the expectation of the total Hamiltonian. A first-order correction to the local approximation was thus included. Quantum-electrodynamic corrections were made. For all elements with atomic numbers ranging from 2 to 106, the following quantities are listed: total energies, electron kinetic energies, electron-nucleus potential energies, electron-electron potential energies consisting of electrostatic and Breit interaction (magnetic and retardation) terms, and vacuum polarization energies. Binding energies including relaxation are listed for all electrons in all atoms over the indicated range of atomic numbers. A self-energy correction is included for the 1s, 2s, and 2p(1/2) levels. Results for selected atoms are compared with energies calculated by other methods and with experimental values.

  9. Theoretical studies on light emission characteristics of high-efficiency BInGaN/GaN quantum well structures with blue spectral range

    NASA Astrophysics Data System (ADS)

    Park, Seoung-Hwan; Ahn, Doyeol

    2016-08-01

    Light emission characteristics of blue BxInyGa1-x-y N/GaN quantum well (QW) structures were using the multiband effective-mass theory. The In composition (y) to give the transition wavelength of 440 nm is reduced with the inclusion of the B composition (x). We find that the spontaneous emission peak rapidly increases with increasing x. In particular, the peak intensity of the BInGaN/GaN QW structure with x = 0.18 and y = 0.008 is about twice larger than that of the conventional InGaN/GaN QW structure. This can be explained by the fact that the internal field (-0.40 MV/cm) in the BInGaN well is In greatly reduced, compared to that (-1.04 MV/cm) in the conventional InGaN well. Also, the strain (-1.7%) in the BInGaN well is shown to be reduced slightly, compare to that (-2.0%) in InGaN well. Hence, we expect that BInGaN/GaN QW structures with a reduced strain can be used as a light source with a high efficiency.

  10. GaSb-based composite quantum wells for laser diodes operating in the telecom wavelength range near 1.55-μm

    SciTech Connect

    Cerutti, L.; Rodriguez, J.-B.; Madiomanana, K.; Tournié, E.; Castellano, A.; Bahri, M.; Largeau, L.; Patriarche, G.; Balocchi, A.; Marie, X.; Lelarge, F.

    2015-03-09

    We have investigated in detail the material, optical, and lasing properties of innovative GaInSb/AlInSb composite quantum wells (CQWs). The CQWs are confined by AlGaAsSb barrier layers, and a monolayer-thin AlInSb barrier layer has been inserted within the GaInSb QWs in order to achieve lasing emission within the telecom window. High-resolution X-ray diffraction, transmission electron microscopy, and photoluminescence spectroscopies reveal high structural quality of the samples. Inserting AlInSb layers allows wider QWs, and thus higher gain-material volume and CQW/optical mode overlap. This translates into better laser performances. Near room temperature, a threshold current of 85 mA and an output power of ∼30 mW/uncoated-facet under continuous wave operation are demonstrated at 1.55 μm with 10 μm × 1 mm laser diodes.

  11. Spin-orbital short-range order in the honeycomb-based quantum magnet Ba3CuSb2O9

    NASA Astrophysics Data System (ADS)

    Nakatsuji, Satoru

    2013-03-01

    The realization of quantum correlated matter beyond one dimension has been vigorously pursued in geometrically frustrated spin systems for decades. In frustrated magnetic materials, however, symmetry breaking of orbital and chemical origin is usually found to induce semi-classical spin freezing. In this talk, I present a contrast case where spins and possibly orbitals remain in a liquid state down to low temperature even in a highly disordered structure of 6H-perovskite Ba3CuSb2O9. Our comprehensive experimental analysis indicates that the geometrical frustration of Wannier's Ising antiferromagnet on a triangular lattice can be exploited to build a nano-structured bipartite honeycomb lattice from electric dipolar spin-1/2 molecules. Despite a strong local Jahn-Teller distortion about the Cu2+ ion, the resulting spin-orbital random bond lattice not only retains hexagonal symmetry averaged over time and space, but it supports a gapless excitation spectrum without spin freezing down to ultralow temperatures. This is the work based on the collaboration with K. Kuga, K. Kimura, R. Satake, N. Katayama, E. Nishibori, H. Sawa, R. Ishii, M. Hagiwara, F. Bridges, T. U. Ito, W. Higemoto, Y. Karaki, M. Halim, A. A. Nugroho, J. A. Rodriguez-Rivera, M. A. Green, C. Broholm. This work is partially supported by Grant-in-Aid for Scientific Research (No. 20340089,21684019) from JSPS, by Grant-in-Aid for Scientific Research on Priority Areas (No. 1951010,19052003) from MEXT, Japan.

  12. Coherent forward and backward diffraction radiation of relativistic electrons in a dielectric targets

    NASA Astrophysics Data System (ADS)

    Naumenko, G. A.; Shevelev, M. V.; Popov, Yu A.

    2016-08-01

    During the interaction of the relativistic electrons field with a dielectric target various types of electromagnetic radiation, such as Cerenkov radiation, diffraction radiation, transition radiation can be generated. In this report we present the results of experimental studies of the diffraction radiation generated by relativistic electrons in a dielectric target at the interface vacuum-insulator and insulator-conductor in the millimeter wavelength range. The experimental results show that the component of the diffraction radiation of relativistic electrons at the interface insulator-conductor, for any significant refractive index of insulator, is suppressed. The analysis of the results from different points of view was done.

  13. Cold and ultracold dynamics of the barrierless D{sup +} + H{sub 2} reaction: Quantum reactive calculations for ∼R{sup −4} long range interaction potentials

    SciTech Connect

    Lara, Manuel; Jambrina, P. G.; Aoiz, F. J.; Launay, J.-M.

    2015-11-28

    Quantum reactive and elastic cross sections and rate coefficients have been calculated for D{sup +} + H{sub 2} (v = 0, j = 0) collisions in the energy range from 10{sup −8} K (deep ultracold regime), where only one partial wave is open, to 150 K (Langevin regime) where many of them contribute. In systems involving ions, the ∼R{sup −4} behavior extends the interaction up to extremely long distances, requiring a special treatment. To this purpose, we have used a modified version of the hyperspherical quantum reactive scattering method, which allows the propagations up to distances of 10{sup 5} a{sub 0} needed to converge the elastic cross sections. Interpolation procedures are also proposed which may reduce the cost of exact dynamical calculations at such low energies. Calculations have been carried out on the PES by Velilla et al. [J. Chem. Phys. 129, 084307 (2008)] which accurately reproduces the long range interactions. Results on its prequel, the PES by Aguado et al. [J. Chem. Phys. 112, 1240 (2000)], are also shown in order to emphasize the significance of the inclusion of the long range interactions. The calculated reaction rate coefficient changes less than one order of magnitude in a collision energy range of ten orders of magnitude, and it is found in very good agreement with the available experimental data in the region where they exist (10-100 K). State-to-state reaction probabilities are also provided which show that for each partial wave, the distribution of HD final states remains essentially constant below 1 K.

  14. Relativistic rocket: Dream and reality

    NASA Astrophysics Data System (ADS)

    Semyonov, Oleg G.

    2014-06-01

    The dream of interstellar flights persists since the first pioneers in astronautics and has never died. Many concepts of thruster capable to propel a rocket to the stars have been proposed and the most suitable among them are thought to be photon propulsion and propulsion by the products of proton-antiproton annihilation in magnetic nozzle. This article addresses both concepts allowing for cross-section of annihilation among other issues in order to show their vulnerability and to indicate the problems. The concept of relativistic matter propulsion is substantiated and discussed. The latter is argued to be the most straightforward way to build-up a relativistic rocket firstly because it is based on the existing technology of ion generators and accelerators and secondly because it can be stepped up in efflux power starting from interplanetary spacecrafts powered by nuclear reactors to interstellar starships powered by annihilation reactors. The problems imposed by thermodynamics and heat disposal are accentuated.

  15. Classical-Quantum Correspondence by Means of Probability Densities

    NASA Technical Reports Server (NTRS)

    Vegas, Gabino Torres; Morales-Guzman, J. D.

    1996-01-01

    Within the frame of the recently introduced phase space representation of non relativistic quantum mechanics, we propose a Lagrangian from which the phase space Schrodinger equation can be derived. From that Lagrangian, the associated conservation equations, according to Noether's theorem, are obtained. This shows that one can analyze quantum systems completely in phase space as it is done in coordinate space, without additional complications.

  16. Relativistic gravity and parity-violating nonrelativistic effective field theories

    NASA Astrophysics Data System (ADS)

    Wu, Chaolun; Wu, Shao-Feng

    2015-06-01

    We show that the relativistic gravity theory can offer a framework to formulate the nonrelativistic effective field theory in a general coordinate invariant way. We focus on the parity violating case in 2 +1 dimensions which is particularly appropriate for the study on quantum Hall effects and chiral superfluids. We discuss how the nonrelativistic spacetime structure emerges from relativistic gravity. We present covariant maps and constraints that relate the field contents in the two theories, which also serve as the holographic dictionary in the context of gauge/gravity duality. A low energy effective action for fractional quantum Hall states is constructed, which captures universal geometric properties and generates nonuniversal corrections systematically. We give another holographic example with dyonic black brane background to calculate thermodynamic and transport properties of strongly coupled nonrelativistic fluids in magnetic field. In particular, by identifying the shift function in the gravity as a minus of guiding center velocity, we obtain the Hall viscosity with its relation to Landau orbital angular momentum density proportional to Wen-Zee shift. Our formalism has a good projection to lowest Landau level.

  17. Pythagoras Theorem and Relativistic Kinematics

    NASA Astrophysics Data System (ADS)

    Mulaj, Zenun; Dhoqina, Polikron

    2010-01-01

    In two inertial frames that move in a particular direction, may be registered a light signal that propagates in an angle with this direction. Applying Pythagoras theorem and principles of STR in both systems, we can derive all relativistic kinematics relations like the relativity of simultaneity of events, of the time interval, of the length of objects, of the velocity of the material point, Lorentz transformations, Doppler effect and stellar aberration.

  18. Relativistic opacities for astrophysical applications

    DOE PAGES

    Fontes, Christopher John; Fryer, Christopher Lee; Hungerford, Aimee L.; Hakel, Peter; Colgan, James Patrick; Kilcrease, David Parker; Sherrill, Manalo Edgar

    2015-06-29

    Here, we report on the use of the Los Alamos suite of relativistic atomic physics codes to generate radiative opacities for the modeling of astrophysically relevant plasmas under local thermodynamic equilibrium (LTE) conditions. The atomic structure calculations are carried out in fine-structure detail, including full configuration interaction. Three example applications are considered: iron opacities at conditions relevant to the base of the solar convection zone, nickel opacities for the modeling of stellar envelopes, and samarium opacities for the modeling of light curves produced by neutron star mergers. In the first two examples, comparisons are made between opacities that are generatedmore » with the fully and semi-relativistic capabilities in the Los Alamos suite of codes. As expected for these highly charged, iron-peak ions, the two methods produce reasonably similar results, providing confidence that the numerical methods have been correctly implemented. However, discrepancies greater than 10% are observed for nickel and investigated in detail. In the final application, the relativistic capability is used in a preliminary investigation of the complicated absorption spectrum associated with cold lanthanide elements.« less

  19. Quantum chaos inside space-temporal Sinai billiards

    NASA Astrophysics Data System (ADS)

    Addazi, Andrea

    2016-04-01

    We discuss general aspects of non-relativistic quantum chaos theory of scattering of a quantum particle on a system of a large number of naked singularities. We define such a system space-temporal Sinai billiard. We discuss the problem in semiclassical approach. We show that in semiclassical regime the formation of trapped periodic semiclassical orbits inside the system is unavoidable. This leads to general expression of survival probabilities and scattering time delays, expanded to the chaotic Pollicott-Ruelle resonances. Finally, we comment on possible generalizations of these aspects to relativistic quantum field theory.

  20. EDITORIAL: Focus on Quantum Control

    NASA Astrophysics Data System (ADS)

    Rabitz, Herschel

    2009-10-01

    Control of quantum phenomena has grown from a dream to a burgeoning field encompassing wide-ranging experimental and theoretical activities. Theoretical research in this area primarily concerns identification of the principles for controlling quantum phenomena, the exploration of new experimental applications and the development of associated operational algorithms to guide such experiments. Recent experiments with adaptive feedback control span many applications including selective excitation, wave packet engineering and control in the presence of complex environments. Practical procedures are also being developed to execute real-time feedback control considering the resultant back action on the quantum system. This focus issue includes papers covering many of the latest advances in the field. Focus on Quantum Control Contents Control of quantum phenomena: past, present and future Constantin Brif, Raj Chakrabarti and Herschel Rabitz Biologically inspired molecular machines driven by light. Optimal control of a unidirectional rotor Guillermo Pérez-Hernández, Adam Pelzer, Leticia González and Tamar Seideman Simulating quantum search algorithm using vibronic states of I2 manipulated by optimally designed gate pulses Yukiyoshi Ohtsuki Efficient coherent control by sequences of pulses of finite duration Götz S Uhrig and Stefano Pasini Control by decoherence: weak field control of an excited state objective Gil Katz, Mark A Ratner and Ronnie Kosloff Multi-qubit compensation sequences Y Tomita, J T Merrill and K R Brown Environment-invariant measure of distance between evolutions of an open quantum system Matthew D Grace, Jason Dominy, Robert L Kosut, Constantin Brif and Herschel Rabitz Simplified quantum process tomography M P A Branderhorst, J Nunn, I A Walmsley and R L Kosut Achieving 'perfect' molecular discrimination via coherent control and stimulated emission Stephen D Clow, Uvo C Holscher and Thomas C Weinacht A convenient method to simulate and visually

  1. On the Simulation of the Laser Ranging Instrument for GRACE Follow-on

    NASA Astrophysics Data System (ADS)

    Darbeheshti, N.; Mueller, V.; Hewitson, M.; Heinzel, G.

    2015-12-01

    GRACE Follow-On will be the first satellite mission to use inter-satellite laser interferometryin space. The laser ranging instrument (LRI) will provide two additional measurements compared to GRACE mission: Interferometric inter-satellite ranging with nanometer precisionand inter-satellite pointing information from Differential wavefront Sensing.We will discuss these two LRI measurements and errors; and present models how to simulate two major noise sources in LRI, namely pointing jitter and laser frequency noise.The LRI simulated data will be available to the geodesy community by Geo-Q (Relativistic Geodesy and Gravimetry with Quantum Sensors) project before the GRACE Follow-On launch to enable the timely development of data analysis tools around the world.The LRI simulation will demonstrate potentials and limitations of the LRI measurements for gravity field recovery.

  2. Relativistic three-body bound states in scalar QFT: Variational basis-state approach

    SciTech Connect

    Emami-Razavi, Mohsen; Bergeron, Nantel; Darewych, Jurij W.; Kowalski, Marian

    2009-10-15

    We use the Hamiltonian formalism of quantum field theory and the variational basis-state method to derive relativistic three-body wave equations for scalar particles interacting via a massive or massless mediating scalar field (the scalar Yukawa model). A variational trial state comprised of three and five Fock-space states is used to derive coupled wave equations for a relativistic three- (and five-) body system. Approximate variational three-body ground-state solutions of the relativistic equations are obtained for various strengths of coupling, for both massive and massless mediating fields. The results show that the inclusion of virtual pairs has a large effect on the three-body binding energy at strong coupling.

  3. Relativistic high harmonics and (sub-)attosecond pulses: relativistic spikes and relativistic mirror

    NASA Astrophysics Data System (ADS)

    Pukhov, A.; Baeva, T.; An der Brügge, D.; Münster, S.

    2009-11-01

    Using particle-in-cell simulations, we study high harmonic generation from overdense plasmas in the relativistic regime. Different incidence angles as well as different laser polarizations are considered and scalings are recovered. It is shown that the theory of relativistic spikes and the BGP power-law spectra [Phys. Rev. E 74, 046404 (2006)] describes well the normal incidence and s-polarized obliquely incident laser pulses. In the case of p-polarized laser pulses, exceptions from the BGP theory can appear when the quasi-static vector potential build-up at the plasma boundary becomes equal to that of the laser. In this case, the spectrum flattens significantly and has a lower cutoff.

  4. Relativistic Navigation: A Theoretical Foundation

    NASA Technical Reports Server (NTRS)

    Turyshev, Slava G.

    1996-01-01

    We present a theoretical foundation for relativistic astronomical measurements in curved space-time. In particular, we discuss a new iterative approach for describing the dynamics of an isolated astronomical N-body system in metric theories of gravity. To do this, we generalize the Fock-Chandrasekhar method of the weak-field and slow-motion approximation (WFSMA) and develop a theory of relativistic reference frames (RF's) for a gravitationally bounded many-extended-body problem. In any proper RF constructed in the immediate vicinity of an arbitrary body, the N-body solutions of the gravitational field equations are formally presented as a sum of the Riemann-flat inertial space-time, the gravitational field generated by the body itself, the unperturbed solutions for each body in the system transformed to the coordinates of this proper RF, and the gravitational interaction term. We develop the basic concept of a general WFSMA theory of the celestial RF's applicable to a wide class of metric theories of gravity and an arbitrary model of matter distribution. We apply the proposed method to general relativity. Celestial bodies are described using a perfect fluid model; as such, they possess any number of internal mass and current multipole moments that explicitly characterize their internal structures. The obtained relativistic corrections to the geodetic equations of motion arise because of a coupling of the bodies' multiple moments to the surrounding gravitational field. The resulting relativistic transformations between the different RF's extend the Poincare group to the motion of deformable self-gravitating bodies. Within the present accuracy of astronomical measurements we discuss the properties of the Fermi-normal-like proper RF that is defined in the immediate vicinity of the extended compact bodies. We further generalize the proposed approximation method and include two Eddington parameters (gamma, Beta). This generalized approach was used to derive the

  5. Loading relativistic Maxwell distributions in particle simulations

    SciTech Connect

    Zenitani, Seiji

    2015-04-15

    Numerical algorithms to load relativistic Maxwell distributions in particle-in-cell (PIC) and Monte-Carlo simulations are presented. For stationary relativistic Maxwellian, the inverse transform method and the Sobol algorithm are reviewed. To boost particles to obtain relativistic shifted-Maxwellian, two rejection methods are proposed in a physically transparent manner. Their acceptance efficiencies are ≈50% for generic cases and 100% for symmetric distributions. They can be combined with arbitrary base algorithms.

  6. Relativistic radiation transport in dispersive media

    SciTech Connect

    Kichenassamy, S.; Krikorian, R.A.

    1985-10-15

    A general-relativistic radiative transfer equation in an isotropic, weakly absorbing, nonmagnetized dispersive medium is derived using the kinetic-theoretical approach and the relativistic Hamiltonian theory of geometrical optics in those media. It yields the generally accepted classical equation in the special-relativistic approximation and in stationary conditions. The influence of the gravitational field and of space-time variations of the refractive index n on the radiation distribution is made explicit in the case of spherical symmetry.

  7. Mesoscopic Superposition States in Relativistic Landau Levels

    SciTech Connect

    Bermudez, A.; Martin-Delgado, M. A.; Solano, E.

    2007-09-21

    We show that a linear superposition of mesoscopic states in relativistic Landau levels can be built when an external magnetic field couples to a relativistic spin 1/2 charged particle. Under suitable initial conditions, the associated Dirac equation produces unitarily superpositions of coherent states involving the particle orbital quanta in a well-defined mesoscopic regime. We demonstrate that these mesoscopic superpositions have a purely relativistic origin and disappear in the nonrelativistic limit.

  8. Relativistic Celestial Mechanics of the Solar System

    NASA Astrophysics Data System (ADS)

    Kopeikin, Sergei; Efroimsky, Michael; Kaplan, George

    2011-09-01

    The general theory of relativity was developed by Einstein a century ago. Since then, it has become the standard theory of gravity, especially important to the fields of fundamental astronomy, astrophysics, cosmology, and experimental gravitational physics. Today, the application of general relativity is also essential for many practical purposes involving astrometry, navigation, geodesy, and time synchronization. Numerous experiments have successfully tested general relativity to a remarkable level of precision. Exploring relativistic gravity in the solar system now involves a variety of high-accuracy techniques, for example, very long baseline radio interferometry, pulsar timing, spacecraft Doppler tracking, planetary radio ranging, lunar laser ranging, the global positioning system (GPS), torsion balances and atomic clocks. Over the last few decades, various groups within the International Astronomical Union have been active in exploring the application of the general theory of relativity to the modeling and interpretation of high-accuracy astronomical observations in the solar system and beyond. A Working Group on Relativity in Celestial Mechanics and Astrometry was formed in 1994 to define and implement a relativistic theory of reference frames and time scales. This task was successfully completed with the adoption of a series of resolutions on astronomical reference systems, time scales, and Earth rotation models by the 24th General Assembly of the IAU, held in Manchester, UK, in 2000. However, these resolutions only form a framework for the practical application of relativity theory, and there have been continuing questions on the details of the proper application of relativity theory to many common astronomical problems. To ensure that these questions are properly addressed, the 26th General Assembly of the IAU, held in Prague in August 2006, established the IAU Commission 52, "Relativity in Fundamental Astronomy". The general scientific goals of the new

  9. Magnetic short-range correlations and quantum critical scattering in the non-Fermi liquid regime of URu{sub 2-x}Re{sub x}Si{sub 2} (x = 0.2-0.6).

    SciTech Connect

    Krishnamurthy, V. V.; Adroja, D. T.; Butch, N. P.; Osborn, R.; Sinha, S. K.; Robertson, J. L.; Aronson, M. C.; Nagler, S. E.; Maple, M. B.; ORNL; Rutherford Appleton Lab.; Univ. California at San Diego; Univ. Michigan

    2008-01-01

    The spin dynamics of uranium ions in the non-Fermi liquid compounds URu{sub 2-x}Re{sub x}Si{sub 2}, for x=0.2 to 0.6, have been investigated using inelastic neutron scattering. The wave vector (q) dependence of the magnetic scattering provides evidence of short-range antiferromagnetic correlations at low temperatures for x=0.2,0.25, but the scattering is nearly q independent at x=0.35,0.6. The magnetic response, {bar S}({omega}), obtained from the q-independent part of neutron scattering, varies as {omega}{sup -{alpha}} with a composition-dependent exponent {alpha} = 0.2-0.5. The dynamic magnetic susceptibility {chi}{double_prime}(q,{omega}) of the q-independent part exhibits {omega}/T scaling for the energy transfer {bar h}{omega} between 3.5 and 17 meV in the temperature (T) range of 5-300 K at all the compositions. This scaling, which indicates local quantum criticality, breaks down in the q range, 0.6-1.1 {angstrom}{sup -1} at x = 0.2 and 0.25, that is dominated by short-range antiferromagnetic correlations. The appearance of power laws in the magnetic response measured by inelastic neutron scattering over a wide Re doping region indicates a disorder driven non-Fermi liquid mechanism for the low-temperature physical properties in these compounds.

  10. Dissipation in relativistic pair-plasma reconnection

    SciTech Connect

    Hesse, Michael; Zenitani, Seiji

    2007-11-15

    An investigation into the relativistic dissipation in magnetic reconnection is presented. The investigated system consists of an electron-positron plasma. A relativistic generalization of Ohm's law is derived. A set of numerical simulations is analyzed, composed of runs with and without guide magnetic field, and of runs with different species temperatures. The calculations indicate that the thermal inertia-based dissipation process survives in relativistic plasmas. For antiparallel reconnection, it is found that the pressure tensor divergence remains the sole contributor to the reconnection electric field, whereas relativistic guide field reconnection exhibits a similarly important role of the bulk inertia terms.

  11. Relativistic Bernstein waves in a degenerate plasma

    SciTech Connect

    Ali, Muddasir; Hussain, Azhar; Murtaza, G.

    2011-09-15

    Bernstein mode for a relativistic degenerate electron plasma is investigated. Using relativistic Vlasov-Maxwell equations, a general expression for the conductivity tensor is derived and then employing Fermi-Dirac distribution function a generalized dispersion relation for the Bernstein mode is obtained. Two limiting cases, i.e., non-relativistic and ultra-relativistic are discussed. The dispersion relations obtained are also graphically presented for some specific values of the parameters depicting how the propagation characteristics of Bernstein waves as well as the Upper Hybrid oscillations are modified with the increase in plasma number density.

  12. Dissipation in Relativistic Pair-Plasma Reconnection

    NASA Technical Reports Server (NTRS)

    Hesse, Michael; Zenitani, Seiji

    2007-01-01

    We present an investigation of the relativistic dissipation in magnetic reconnection. The investigated system consists of an electron-positron plasma. A relativistic generalization of Ohm's law is derived. We analyze a set of numerical simulations, composed of runs with and without guide magnetic field, and of runs with different species temperatures. The calculations indicate that the thermal inertia-based dissipation process survives in relativistic plasmas. For anti-parallel reconnection, it is found that the pressure tensor divergence remains the sole contributor to the reconnection electric field, whereas relativistic guide field reconnection exhibits a similarly important role of the bulk inertia terms.

  13. Relativistic and non-relativistic solitons in plasmas

    NASA Astrophysics Data System (ADS)

    Barman, Satyendra Nath

    This thesis entitled as "Relativistic and Non-relativistic Solitons in Plasmas" is the embodiment of a number of investigations related to the formation of ion-acoustic solitary waves in plasmas under various physical situations. The whole work of the thesis is devoted to the studies of solitary waves in cold and warm collisionless magnetized or unmagnetized plasmas with or without relativistic effect. To analyze the formation of solitary waves in all our models of plasmas, we have employed two established methods namely - reductive perturbation method to deduce the Korteweg-de Vries (KdV) equation, the solutions of which represent the important but near exact characteristic concepts of soliton-physics. Next, the pseudopotential method to deduce the energy integral with total nonlinearity in the coupling process for exact characteristic results of solitons has been incorporated. In Chapter 1, a brief description of plasma in nature and laboratory and its generation are outlined elegantly. The nonlinear differential equations to characterize solitary waves and the relevant but important methods of solutions have been mentioned in this chapter. The formation of solitary waves in unmagnetized and magnetized plasmas, and in relativistic plasmas has been described through mathematical entity. Applications of plasmas in different fields are also put forwarded briefly showing its importance. The study of plasmas as they naturally occur in the universe encompasses number of topics including sun's corona, solar wind, planetary magnetospheres, ionospheres, auroras, cosmic rays and radiation. The study of space weather to understand the universe, communications and the activities of weather satellites are some useful areas of space plasma physics. The surface cleaning, sterilization of food and medical appliances, killing of bacteria on various surfaces, destroying of viruses, fungi, spores and plasma coating in industrial instruments ( like computers) are some of the fields

  14. Increasing complexity with quantum physics.

    PubMed

    Anders, Janet; Wiesner, Karoline

    2011-09-01

    We argue that complex systems science and the rules of quantum physics are intricately related. We discuss a range of quantum phenomena, such as cryptography, computation and quantum phases, and the rules responsible for their complexity. We identify correlations as a central concept connecting quantum information and complex systems science. We present two examples for the power of correlations: using quantum resources to simulate the correlations of a stochastic process and to implement a classically impossible computational task. PMID:21974665

  15. Increasing complexity with quantum physics.

    PubMed

    Anders, Janet; Wiesner, Karoline

    2011-09-01

    We argue that complex systems science and the rules of quantum physics are intricately related. We discuss a range of quantum phenomena, such as cryptography, computation and quantum phases, and the rules responsible for their complexity. We identify correlations as a central concept connecting quantum information and complex systems science. We present two examples for the power of correlations: using quantum resources to simulate the correlations of a stochastic process and to implement a classically impossible computational task.

  16. Nonthermal Particle Acceleration and Radiation in Relativistic Magnetic Reconnection

    NASA Astrophysics Data System (ADS)

    Werner, Gregory

    2015-11-01

    Many spectacular and violent phenomena in the high-energy universe exhibit nonthermal radiation spectra, from which we infer power-law energy distributions of the radiating particles. Relativistic magnetic reconnection, recognized as a leading mechanism of nonthermal particle acceleration, can efficiently transfer magnetic energy to energetic particles. We present a comprehensive particle-in-cell study of particle acceleration in 2D relativistic reconnection in both electron-ion and pair plasmas without guide field. We map out the power-law index α and the high-energy cutoff of the electron energy spectrum as functions of three key parameters: the system size (and initial layer length) L, the ambient plasma magnetization σ, and the ion/electron mass ratio (from 1 to 1836). We identify the transition between small- and large-system regimes: for small L, the system size affects the slope and extent of the high-energy spectrum, while for large enough L, α and the cutoff energy are independent of L. We compare high energy particle spectra and radiative (synchrotron and inverse Compton) signatures of the electrons, for pair and electron-ion reconnection. The latter cases maintain highly relativistic electrons, but include a range of different magnetizations yielding sub- to highly-relativistic ions. Finally, we show how nonthermal acceleration and radiative signatures alter when the radiation back-reaction becomes important. These results have important implications for assessing the promise and the limitations of relativistic reconnection as an astrophysically-important particle acceleration mechanism. This work is funded by NSF, DOE, and NASA.

  17. Quantum critical scaling in graphene.

    PubMed

    Sheehy, Daniel E; Schmalian, Jörg

    2007-11-30

    We show that the emergent relativistic symmetry of electrons in graphene near its quantum critical point (QCP) implies a crucial importance of the Coulomb interaction. We derive scaling laws, valid near the QCP, that dictate the nontrivial magnetic and charge response of interacting graphene. Our analysis yields numerous predictions for how the Coulomb interaction will be manifested in experimental observables such as the diamagnetic response and electronic compressibility. PMID:18233313

  18. Geometrizing the Quantum - A Toy Model

    SciTech Connect

    Koch, Benjamin

    2009-12-15

    It is shown that the equations of relativistic Bohmian mechanics for multiple bosonic particles have a dual description in terms of a classical theory of conformally 'curved' space-time. This shows that it is possible to formulate quantum mechanics as a purely classical geometrical theory. The results are further generalized to interactions with an external electromagnetic field.

  19. Chandra Discovers Relativistic Pinball Machine

    NASA Astrophysics Data System (ADS)

    2006-12-01

    New clues about the origins of cosmic rays, mysterious high-energy particles that bombard the Earth, have been revealed using NASA's Chandra X-ray Observatory. An extraordinarily detailed image of the remains of an exploded star provides crucial insight into the generation of cosmic rays. For the first time, astronomers have mapped the rate of acceleration of cosmic ray electrons in a supernova remnant. The new map shows that the electrons are being accelerated at close to the theoretically maximum rate. This discovery provides compelling evidence that supernova remnants are key sites for energizing charged particles. The map was created from an image of Cassiopeia A, a 325-year-old remnant produced by the explosive death of a massive star. The blue, wispy arcs in the image trace the expanding outer shock wave where the acceleration takes place. The other colors in the image show debris from the explosion that has been heated to millions of degrees. Acceleration Map of Cassiopeia A Acceleration Map of Cassiopeia A "Scientists have theorized since the 1960s that cosmic rays must be created in the tangle of magnetic fields at the shock, but here we can see this happening directly," said Michael Stage of the University of Massachusetts, Amherst. "Explaining where cosmic rays come from helps us to understand other mysterious phenomena in the high-energy universe." Examples are the acceleration of charged particles to high energies in a wide variety of objects, ranging from shocks in the magnetosphere around Earth to awesome extragalactic jets that are produced by supermassive black holes and are thousands of light years in length. Temperature Map of Cassiopeia A Temperature Map of Cassiopeia A Scientists had previously developed a theory to explain how charged particles can be accelerated to extremely high energies - traveling at almost the speed of light - by bouncing back and forth across a shock wave many times. "The electrons pick up speed each time they bounce

  20. Maxwell's equations, quantum physics and the quantum graviton

    NASA Astrophysics Data System (ADS)

    Gersten, Alexander; Moalem, Amnon

    2011-12-01

    Quantum wave equations for massless particles and arbitrary spin are derived by factorizing the d'Alembertian operator. The procedure is extensively applied to the spin one photon equation which is related to Maxwell's equations via the proportionality of the photon wavefunction Ψ to the sum E + iB of the electric and magnetic fields. Thus Maxwell's equations can be considered as the first quantized one-photon equation. The photon wave equation is written in two forms, one with additional explicit subsidiary conditions and second with the subsidiary conditions implicitly included in the main equation. The second equation was obtained by factorizing the d'Alembertian with 4×4 matrix representation of "relativistic quaternions". Furthermore, scalar Lagrangian formalism, consistent with quantization requirements is developed using derived conserved current of probability and normalization condition for the wavefunction. Lessons learned from the derivation of the photon equation are used in the derivation of the spin two quantum equation, which we call the quantum graviton. Quantum wave equation with implicit subsidiary conditions, which factorizes the d'Alembertian with 8×8 matrix representation of relativistic quaternions, is derived. Scalar Lagrangian is formulated and conserved probability current and wavefunction normalization are found, both consistent with the definitions of quantum operators and their expectation values. We are showing that the derived equations are the first quantized equations of the photon and the graviton.