Fractional excitations in the Luttinger liquid
NASA Astrophysics Data System (ADS)
Pham, K.-V.; Gabay, M.; Lederer, P.
2000-06-01
We reconsider the spectrum of the Luttinger liquid (LL) usually understood in terms of phonons (density fluctuations), and within the context of bosonization we give an alternative representation in terms of fractional states. This allows us to make contact with the Bethe Ansatz which predicts similar fractional states. As an example we study the spinon operator in the absence of spin rotational invariance and derive it from first principles: we find that it is not a semion in general; a trial Jastrow wave function is also given for that spinon state. Our construction of the spectroscopy based on fractional states leads to several unique physical insights: in the low-energy limit, we find that the Sz=0 continuum of gapless spin chains is due to pairs of fractional quasiparticle-quasihole states which are the one-dimensional counterpart of the Laughlin fractional Quantum Hall effect quasiparticles. The holon operator for the Luttinger liquid with spin is also derived. In the presence of a magnetic field, spin-charge separation is not realized any longer in a LL: the holon and the spinon are then replaced by new fractional states that we are able to describe.
Excitation energy after a smooth quench in a Luttinger liquid
Jacek Dziarmaga; Marek Tylutki
2011-12-28
Low energy physics of quasi-one-dimensional ultracold atomic gases is often described by a gapless Luttinger liquid (LL). It is nowadays routine to manipulate these systems by changing their parameters in time but, no matter how slow the manipulation is, it must excite a gapless system. We study a smooth change of parameters of the LL (a smooth "quench") with a variable quench time and find that the excitation energy decays with an inverse power of the quench time. This universal exponent is -2 at zero temperature, and -1 for slow enough quenches at finite temperature. The smooth quench does not excite beyond the range of validity of the low energy LL description.
Chiral Luttinger liquid and the edge excitations in the fractional quantum Hall states
X. G. Wen
1990-01-01
The low-energy effective theory of the edge excitations in the fractional quantum Hall (FQH) states is derived. The edge excitations are shown to form a new kind of state which is called the chiral Luttinger liquid (ÏLL). The effective theory is exactly soluble. This enables us to easily calculate all the low-energy properties of the edge excitations. We calculate the
P. J. Burke
2002-01-01
We present a technique to directly excite Luttinger liquid collective modes\\u000ain carbon nanotubes at GHz frequencies. By modeling the nanotube as a\\u000anano-transmission line with distributed kinetic and magnetic inductance as well\\u000aas distributed quantum and electrostatic capacitance, we calculate the complex,\\u000afrequency dependent impedance for a variety of measurement geometries. Exciting\\u000avoltage waves on the nano-transmission line is
Chiral Luttinger liquid and the edge excitations in the fractional quantum Hall states
Wen, X.G. (School of Natural Sciences, Institute for Advanced Study, Princeton, New Jersey 08540 (USA))
1990-06-15
The low-energy effective theory of the edge excitations in the fractional quantum Hall (FQH) states is derived. The edge excitations are shown to form a new kind of state which is called the chiral Luttinger liquid ({chi}LL). The effective theory is exactly soluble. This enables us to easily calculate all the low-energy properties of the edge excitations. We calculate the electron propagator and the spectral function, which clearly demonstrate the non-Fermi-liquid behaviors of the {chi}LL. We also calculate the interference effects between excitations on different edges. We demonstrate that the properties of the edge excitations are closely related to the properties of the FQH states on compacted spaces. Thus the properties of the edge excitations can be used to characterize the topological orders in the FQH states. We also show that the FQH states with filling fractions {nu}{ne}1/{ital l} must have at least two branches of edge excitations.
Fermi liquids and Luttinger liquids
H. J. Schulz; G. Cuniberti; P. Pieri
1998-01-01
In these lecture notes, the basic physics of Fermi liquids and Luttinger liquids is presented. Fermi liquids are discussed both from a phenomenological viewpoint, in relation to microscopic approaches, and as renormalization group fixed points. Luttinger liquids are introduced using the bosonization formalism, and their essential differences with Fermi liquids are pointed out. Applications to transport effects, the effect of
Fractons and Luttinger liquids
Wellington da Cruz
2000-10-05
We consider the concept of fractons as particles or quasiparticles which obey a specific fractal statistics in connection with a one-dimensional Luttinger liquid theory. We obtain a dual statistics parameter ${\\tilde{\
Transport in Luttinger Liquids
NASA Astrophysics Data System (ADS)
Rao, Sumathi
We give a brief introduction to Luttinger liquids and to the phenomena of electronic transport or conductance in quantum wires. We explain why the subject of transport in Luttinger liquids is relevant and fascinating and review some important results on tunneling through barriers in a one-dimensional quantum wire and the phenomena of persistent currents in mesoscopic rings. We give a brief description of our own work on transport through doubly-crossed Luttinger liquids and transport in the Schulz-Shastry exactly solvable Luttinger-like model. With a view to making this article accessible to researchers in diverse fields such as nuclear physics, particle physics, formal field theory and condensed matter physics, we begin by first giving a brief introduction. In Sec. 1, we explain the words such as "Luttinger liquid" and "transport" in the title. We also motivate the study of this subject by showing that field is very important at the current time from the applications point of view and describe why it is theoretically fascinating. We then give a quick review of some of the important results in the field in Sec. 2, before we go on to describe some work that we have recently done and are doing in this field in Sec. 3. Finally, in Sec. 4, we conclude by re-emphasizing the importance of this area and drawing attention towards future possibilities.
A brief introduction to Luttinger liquids
NASA Astrophysics Data System (ADS)
Voit, Johannes
2000-11-01
I give a brief introduction to Luttinger liquids. Luttinger liquids are paramagnetic one-dimensional metals without Landau quasi-particle excitations. The elementary excitations are collective charge and spin modes, leading to charge-spin separation. Correlation functions exhibit power-law behavior. All physical properties can be calculated, e.g. by bosonization, and depend on three parameters only: the renormalized coupling constant K?, and the charge and spin velocities. I also discuss the stability of Luttinger liquids with respect to temperature, interchain coupling, lattice effects and phonons, and list important open problems.
Luttinger-liquid behaviour in carbon nanotubes
NASA Astrophysics Data System (ADS)
Bockrath, Marc; Cobden, David H.; Lu, Jia; Rinzler, Andrew G.; Smalley, Richard E.; Balents, Leon; McEuen, Paul L.
1999-02-01
Electron transport in conductors is usually well described by Fermi-liquid theory, which assumes that the energy states of the electrons near the Fermi level EF are not qualitatively altered by Coulomb interactions. In one-dimensional systems, however, even weak Coulomb interactions cause strong perturbations. The resulting system, known as a Luttinger liquid, is predicted to be distinctly different from its two- and three-dimensional counterparts. For example, tunnelling into a Luttinger liquid at energies near the Fermi level is predicted to be strongly suppressed, unlike in two- and three-dimensional metals. Experiments on one-dimensional semiconductor wires, have been interpreted by using Luttinger-liquid theory, but an unequivocal verification of the theoretical predictions has not yet been obtained. Similarly, the edge excitations seen in fractional quantum Hall conductors are consistent with Luttinger-liquid behaviour, , but recent experiments failed to confirm the predicted relationship between the electrical properties of the bulk state and those of the edge states. Electrically conducting single-walled carbon nanotubes (SWNTs) represent quantum wires that may exhibit Luttinger-liquid behaviour, . Here we present measurements of the conductance of bundles (`ropes') of SWNTs as a function of temperature and voltage that agree with predictions for tunnelling into a Luttinger liquid. In particular, we find that the conductance and differential conductance scale as power laws with respect to temperature and bias voltage, respectively, and that the functional forms and the exponents are in good agreement with theoretical predictions.
Ballistic thermoelectric transport in a Luttinger liquid.
Ivanov, Y V
2010-06-23
The Seebeck and Peltier coefficients of a homogeneous Luttinger liquid are calculated in the ballistic regime. Nonlinearity of the electron spectrum is taken into account. It is shown that, in the framework of the defined approximations, the thermoelectric power of a Luttinger liquid is equal to zero, in agreement with the exponentially small thermopower of a one-dimensional degenerate Fermi gas. The Peltier coefficient is controlled by a nonequilibrium state of the system. It is finite and renormalized by the interaction in the case of a convective flow of a Luttinger liquid. The zero modes of bosonic excitations and the dispersion-induced contribution to the electric current operator are taken into account in calculations. PMID:21393787
Quantum wires as Luttinger liquids: theory
NASA Astrophysics Data System (ADS)
Sassetti, M.; Kramer, B.
The present understanding of the physics of correlated electrons in quantum wires is summarized in terms of non-Fermi liquid collective excitations. The latter are determined within the Luttinger liquid model by using the bosonization technique. Charge and spin density modes are derived. Comparison with the data from resonant Raman scattering experiments indicates that interactions dominate the low-frequency collective excitations. The latter are determined within the Luttinger liquid model by using the bosonization technique. Charge and spin density modes are derived. Comparison with the data from resonant Raman scattering experiments indicates that interactions dominate the low-frequency collective modes in semiconductor quantum wires. Former "single particle excitations" in the resonant Raman spectra have been found to be due to higher-order spin modes that appear in both polarizations of incident and scattered light. The interplay in the non-linear DC-transport properties of a Luttinger liquid model with two impurities between interaction, spin, and backscattering by the impurities is discussed and compared with recent experiments. The results indicate that linear transport probes the global properties of the system, including the leads and the contacts. On the other hand, the non-linear differential conductance probes the local correlations near the electron island between the impurities.
Conductivity in Luttinger Liquids and Beyond
NASA Astrophysics Data System (ADS)
Kuehner, Till D.
2000-03-01
Luttinger Liquids contain the low-energy physics of gap-less strongly interacting quantum systems in one dimension. Several analytical studies of Luttinger Liquids made predictions on their ac-conductivity. Since the dispersion relations of Luttinger Liquids are linearized, it is not clear to which extent these predictions hold for actual quantum lattice Hamiltonians. We use the Density Matrix Renormalization Group (DMRG) to calculate the ac-conductivity for strongly interacting fermions with and without spin, and compare our results to the analytic expectations for the Luttinger Liquids.
Luttinger liquid behavior in carbon nanotubes
NASA Astrophysics Data System (ADS)
Egger, Reinhold
The low-energy theory of metallic carbon nanotubes is derived by bosonization methods. For single-wall nanotubes, the electron-electron interaction destroys the Fermi liquid state and leads to Luttinger liquid behavior. For individual multi-wall nanotubes or a rope of single-wall nanotubes, correlations are also important and can imply Luttinger liquid behavior again. Characteristic Luttinger liquid power laws are found for the tunneling density of states and the linear conductance in the presence of a backscatterer, with exponents approaching their Fermi liquid value only very slowly as the number of conducting shells or tubes increases.
Tunneling between coupled Luttinger liquids
Paul Fendley; Chetan Nayak
2000-08-16
We consider the problem of tunneling between spinless 1D Luttinger liquid chains. We show how to map the problem onto the 4-state chiral clock model together with a free boson for the total charge mode. We use a variety of results, some of them exact, from the integrable chiral Potts model and the study of commensurate/incommensurate transitions to deduce the physics of coupled Luttinger liquids. For those intrachain interaction strengths for which interchain tunneling is relevant, we find that it can lead to the formation of symmetric and antisymmetric bands with split Fermi surfaces, depending on the relative strengths of interchain tunneling and interchain interactions. With split Fermi surfaces, the tunneling is coherent. It is not possible to have two gapless Fermi surfaces with the same Fermi momentum when interchain tunneling is relevant. However, interchain interactions can drive the formation of a gap, in which case interchain transport will be incoherent. We comment on the possible relevance of our results to c-axis transport in high-T_c superconductors.
Anyons in generalized Luttinger liquid models
NASA Astrophysics Data System (ADS)
Pham, K.-V.; Gabay, M.; Lederer, P.
2000-07-01
Schulz and Shastry recently introduced a new class of exactly solvable one-dimensional models with non-Fermi-liquid physics. First, we show that this behavior is caused by the existence of anyonic excitations (i.e. states with non-trivial conformal spin) with charge [(?)/(2?)], where ? is the phase shift of the potential. Since ? is an arbitrary real number, these anyons may therefore carry an irrational charge. Next, in view of this result we revisit the general classification of non-Fermi-liquid two-species gapless 1D models: while it is usually thought that c = 1 × c = 1 theories form a four-parameter space, we establish that the most general non-relativistic conformal field theory has ten parameters. This defines a single larger universality class with sub-manifolds associated with the standard Luttinger liquid (with spin-charge separation), and the Schulz-Shastry class of models.
Spin Injection into a Luttinger Liquid
NASA Astrophysics Data System (ADS)
Si, Qimiao
1998-10-01
We study the effect of spin injection into a Luttinger liquid. The spin-injection-detection setup of Johnson and Silsbee is considered: spins injected into the Luttinger liquid induce, across an interface with a ferromagnetic metal, either a spin-dependent current \\(Is\\) or a spin-dependent boundary voltage \\(Vs\\). We find that the spin-charge separation nature of the Luttinger liquid affects Is and Vs in a very different fashion. In particular, in the Ohmic regime, Vs depends on the spin transport properties of the Luttinger liquid in essentially the same way as it would in the case of a Fermi liquid. The implications of our results for the spin-injection-detection experiments in the high- Tc cuprates are discussed.
Breakdown of the Chiral Luttinger Liquid in One Dimension
NASA Astrophysics Data System (ADS)
Ho, A. F.; Coleman, P.
1999-08-01
We have developed a fermionic boot-strap method to solve a class of chiral one-dimensional fermion models. Using this scheme, we show that Luttinger liquid behavior in a gas of four interacting chiral Majorana fermions is highly sensitive to the velocity degeneracy. Upon changing the velocity of one chiral fermion, a sharp bound (or antibound) state splits off from the original Luttinger liquid continuum, cutting off the x-ray singularity to form a broad incoherent excitation with a lifetime that grows linearly with frequency.
Particle partition entanglement of bosonic Luttinger liquids
C. M. Herdman; A. Del Maestro
2015-02-25
We consider the R\\'{e}nyi entanglement entropy of bosonic Luttinger liquids under a particle bipartition and demonstrate that the leading order finite-size scaling is logarithmic in the system size with a prefactor equal to the inverse Luttinger parameter. While higher order corrections involve a microscopic length scale, the leading order scaling depends only on this sole dimensionless parameter which characterizes the low energy quantum hydrodynamics. This result contrasts the leading entanglement entropy scaling under a spatial bipartition, for which the coefficient is universal and independent of the Luttinger parameter. Using quantum Monte Carlo calculations, we explicitly confirm the scaling predictions of Luttinger liquid theory for the Lieb-Liniger model of $\\delta$-function interacting bosons in the one dimensional spatial continuum.
Anomalous Superconductivity in Coupled Luttinger Liquids
NASA Astrophysics Data System (ADS)
Mastropietro, Vieri
According to Anderson ([1&rsqb,; p. 54) ``the equivalent of BCS theory for a fully spin-charge separated Luttinger liquid has not been formally worked out''. We consider a model for two one-dimensional spinning Luttinger liquids coupled via a Cooper tunnelling Hamiltonian. We show that the partition function is the four-dimensional integral of an exponential whose exponent has an extremal point obtained solving an anomalous non-BCS self-consistence equation. If the extremal point is a global minimum the model is completely solved by the saddle point theorem and the anomalous gap generation is proved. We find that the Luttinger interaction enhances strongly Tc if the intrachain Luttinger interaction is much bigger than the interchain interaction.
Particle partition entanglement of bosonic Luttinger liquids
NASA Astrophysics Data System (ADS)
Herdman, C. M.; Del Maestro, A.
2015-05-01
We consider the Rényi entanglement entropy of bosonic Tomonaga-Luttinger liquids under a particle bipartition and demonstrate that the leading order finite-size scaling is logarithmic in the system size with a prefactor equal to the inverse Luttinger parameter. While higher-order corrections involve a microscopic length scale, the leading-order scaling depends only on this sole dimensionless parameter which characterizes the low-energy quantum hydrodynamics. This result contrasts the leading entanglement entropy scaling under a spatial bipartition, for which the coefficient is universal and independent of the Luttinger parameter. Using quantum Monte Carlo calculations, we explicitly confirm the scaling predictions of Tomonaga-Luttinger liquid theory for the Lieb-Liniger model of ? -function interacting bosons in the one-dimensional spatial continuum.
Equilibration in a chiral Luttinger liquid
NASA Astrophysics Data System (ADS)
Protopopov, I. V.; Gutman, D. B.; Mirlin, A. D.
2015-05-01
We explore the weak-strong-coupling Bose-Fermi duality in a model of a single-channel integer or fractional quantum Hall edge state with a finite-range interaction. The system is described by a chiral Luttinger liquid with nonlinear dispersion of bosonic and fermonic excitations. We use the bosonization, a unitary transformation, and a refermionization to map the system onto that of weakly interacting fermions at low temperature T or weakly interacting bosons at high T . We calculate the equilibration rate which is found to scale with temperature as T5 and T14 in the high-temperature ("bosonic") and the low-temperature ("fermonic") regimes, respectively. The relaxation rate of a hot particle with the momentum k in the fermonic regime scales as k7T7 .
Dimensional crossover from Fermi to Luttinger liquid
Castellani, C.; Di Castro, C.; Metzner, W. (Dipartimento di Fisica, Universita La Sapienza'', piazzale A. Moro 2, 00185 Roma (Italy))
1994-01-17
We analyze the low energy behavior of interacting fermions in continuous dimensions [ital d] between one and two. It is shown that Fermi liquid fixed points are stable with respect to residual scattering of quasiparticles by regular interactions in any dimension above one, while the structure of corrections to quasiparticle behavior changes drastically below two dimensions. The crossover from Luttinger liquid behavior in 1D to Fermi liquid behavior in higher dimensions is described by a tomographic Luttinger model with effective interactions approaching zero with a power [ital d][minus]1 of the distance from the Fermi surface.
Luttinger-liquid behaviour in carbon nanotubes
Marc Bockrath; David H. Cobden; Jia Lu; Andrew G. Rinzler; Richard E. Smalley; Leon Balents; Paul L. McEuen
1999-01-01
Electron transport in conductors is usually well described by Fermi-liquid theory, which assumes that the energy states of the electrons near the Fermi level EF are not qualitatively altered by Coulomb interactions. In one-dimensional systems, however, even weak Coulomb interactions cause strong perturbations. The resulting system, known as a Luttinger liquid, is predicted to be distinctly different from its two-
Kondo effect in crossed Luttinger liquids
NASA Astrophysics Data System (ADS)
Le Hur, Karyn
2000-01-01
We present results for the Kondo effect in two crossed Luttinger liquids by using boundary conformal field theory. We predict two types of critical behaviors: either a two-channel Kondo fixed point with a nonuniversal Wilson ratio or a theory with an anomalous reponse that is identical to that found by Furusaki and Nagaosa for the Kondo effect in a single Luttinger liquid. Moreover, we discuss the relevance of perturbations like channel anisotropy in restoring a Fermi-liquid-like Kondo fixed point, and compare our results with the Kondo effect in a two-band Hubbard system modeled by a channel-dependent Luttinger Hamiltonian. The suppression of backscattering off the impurity produces a model similar to the four-channel Kondo theory. Consequences are discussed.
Fermionic Luttinger liquids from a microscopic perspective
Manuel Valiente; Lawrence G. Phillips; Nikolaj T. Zinner; Patrik Ohberg
2015-05-13
We consider interacting one-dimensional, spinless Fermi gases, whose low-energy properties are described by Luttinger liquid theory. We perform a systematic, in-depth analysis of the relation between the macroscopic, phenomenological parameters of Luttinger liquid effective field theory, and the microscopic interactions of the Fermi gas. In particular, we begin by explaining how to model effective interactions in one dimension, which we then apply to the main forward scattering channel -- the interbranch collisions -- common to these systems. We renormalise the corresponding interbranch phenomenological constants in favour of scattering phase shifts. Interestingly, our renormalisation procedure shows (i) how Luttinger's model arises in a completely natural way -- and not as a convenient approximation -- from Tomonaga's model, and (ii) the reasons behind the interbranch coupling constant remaining unrenormalised in Luttinger's model. We then consider the so-called intrabranch processes, whose phenomenological coupling constant is known to be fixed by charge conservation, but whose microscopic origin is not well understood. We show that, contrary to general belief and common sense, the intrabranch interactions appearing in Luttinger liquid theory do not correspond to an intrabranch scattering channel, nor an energy shift due to intrabranch interactions, in the microscopic theory. Instead, they are due to interbranch processes. We finally apply our results to a particular example of an exactly solvable model, namely the fermionic dual to the Lieb-Liniger model in the Tonks-Girardeau and super-Tonks-Girardeau regimes.
Spin Dimers: from BEC to Luttinger liquids
NASA Astrophysics Data System (ADS)
Giamarchi, Thierry
2011-03-01
Localized spin systems, and in particular dimer systems, provide a fantastic laboratory to study the interplay between quantum effects and the interaction between excitations. Magnetic field and temperature allow an excellent control on the density of excitations and various very efficient probes such as neutrons and NMR are available. They can thus be used as ``quantum simulators'' to tackle with great success questions that one would normally search in itinerant interacting quantum systems. In particular they have provided excellent realizations of Bose-Einstein condensates [1,2]. This allowed not only to probe the properties of interacting bosons in a variety of dimensions but also to study in a controlled way additional effects such as disorder. If the dimensionality is reduced they also allow to test in a quantitative way Luttinger liquid physics [3,4,5]. I will discuss these various cases, and show that we have now good theoretical tools to make quantitative comparisons with the experiments. Finally, how to go from this low dimensional case where the spins behave essentially as fermions, to the higher dimensional case where they behave as (essentially free) bosons, is a very challenging, and experimentally relevant issue. This work was supported in part by the Swiss SNF under MaNEP and division II.
Luttinger Liquid Behavior in Multiwall Carbon Nanotubes
NASA Astrophysics Data System (ADS)
Egger, Reinhold
1999-12-01
The low-energy theory for multiwall carbon nanotubes including the long-ranged Coulomb interactions, internal screening effects, and single-electron hopping between graphite shells is derived and analyzed by bosonization methods. Characteristic Luttinger liquid power laws are found for the tunneling density of states, with exponents approaching their Fermi liquid value only very slowly as the number of conducting shells increases. With minor modifications, the same conclusions apply to transport in ropes of single-wall nanotubes.
Thermal Transport in a Luttinger Liquid
C. L. Kane; Matthew P. A. Fisher
1996-01-01
We study thermal transport in a one-dimensional (1d) interacting electron\\u000agas, employing the Luttinger liquid model. Both thermal conductance and\\u000athermopower are analyzed for a pure 1d gas and with impurities. The universal\\u000aratio of electrical to thermal conductance in a Fermi-liquid - the\\u000aWiedeman-Franz law - is modified, whereas the thermopower is still linear in\\u000atemperature. For a single
Luttinger Liquid Behavior in Multiwall Carbon Nanotubes
Reinhold Egger; A. Bachtold; M. Fuhrer; M. Bockrath; D. Cobden; P. McEuen
1999-01-01
The low-energy theory for multiwall carbon nanotubes including the long-ranged Coulomb interactions, internal screening effects, and single-electron hopping between graphite shells is derived and analyzed by bosonization methods. Characteristic Luttinger liquid power laws are found for the tunneling density of states, with exponents approaching their Fermi liquid value only very slowly as the number of conducting shells increases. With minor
Interface resistances and AC transport in a Luttinger liquid
K.-V. Pham
2003-01-01
We consider a Luttinger liquid (LL) connected to two reservoirs when the two sample-reservoir interface resistances R S and R D are arbitrary (not necessarily quantized at half-the-quantum of resistance). We compute exactly the dynamical impedance of a Luttinger liquid and generalize earlier expressions for its dynamical conductance in the following situations. (i) We first consider a gated Luttinger liquid.
Multiwalled carbon nanotube: Luttinger versus Fermi liquid
R. Tarkiainen; M. Ahlskog; J. Penttilä; L. Roschier; P. Hakonen; M. Paalanen; E. Sonin
2001-01-01
We have measured IV curves of multiwalled carbon nanotubes using end contacts. At low voltages, the tunneling conductance obeys non-Ohmic power law, which is predicted both by the Luttinger liquid and the environment-quantum-fluctuation theories. However, at higher voltages we observe a crossover to Ohm's law with a Coulomb-blockade offset, which agrees with the environment-quantum-fluctuation theory, but cannot be explained by
Response functions in multicomponent Luttinger liquids
NASA Astrophysics Data System (ADS)
Orignac, E.; Citro, R.
2012-12-01
We derive an analytic expression for the zero temperature Fourier transform of the density-density correlation function of a multicomponent Luttinger liquid with different velocities. By employing a Schwinger identity and a generalized Feynman identity exact integral expressions are derived, and approximate analytical forms are given for frequencies close to each component singularity. We find power-law singularities and compute the corresponding exponents. Numerical results are shown for N = 3 components and implications for experiments on cold atoms are discussed.
Measure of equilibration in Luttinger liquids
NASA Astrophysics Data System (ADS)
Medvedyeva, Mariya; Kehrein, Stefan
2015-03-01
We consider the properties of the Luttinger liquid in the echo protocol (forward evolution in time followed by the backward evolution of slightly perturbed system) and explore the relation of the Loschmidt echo (the overlap of the initial and final wavefunctions) and the measurable properties of the system. We first study the linear Luttinger liquid as an example of an integrable system and find that the momentum distribution function exhibits almost complete recurrence while the Loschmidt echo does not, as the diagonal basis is different during the forward and backward time evolution. For a nonlinear Luttinger liquid the recurrence strength of the momentum distribution function drops as the nonlinearity of the fermion dispersion relation grows. We conclude that there is no simple relation of the Loschmidt echo to the behavior of the observables and that more work is needed to understand how to interpret the echo in the context of experiment. This work was supported through SFB 1073 (project B03) of the Deutsche Forschungsgemeinschaft (DFG).
Electrical and Thermal Transport in Inhomogeneous Luttinger Liquids
NASA Astrophysics Data System (ADS)
DeGottardi, Wade; Matveev, K. A.
2015-06-01
We study the transport properties of long quantum wires by generalizing the Luttinger liquid approach to allow for the finite lifetime of the bosonic excitations. Our theory accounts for long-range disorder and strong electron interactions, both of which are common features of experiments with quantum wires. We obtain the electrical and thermal resistances and thermoelectric properties of such quantum wires and find a strong deviation from perfect conductance quantization. We cast our results in terms of the thermal conductivity and bulk viscosity of the electron liquid and give the temperature scale above which the transport can be described by classical hydrodynamics.
Resonant heat transport through a Luttinger liquid
NASA Astrophysics Data System (ADS)
Krive, I. V.
1999-05-01
Thermal transport through one-dimensional systems of strongly interacting electrons is studied in two cases: (i) a finite Luttinger liquid (LL) wire containing a strong impurity, and (ii) a LL ring connected by quantum wires to noninteracting electron reservoirs. It is shown that, for (i), a temperature-induced resonant transport takes place under certain conditions. In case (ii) the heat conductance under resonance conditions does not depend on the electron-electron interaction and the system thermal conductance coincides with the maximal Fermi-liquid thermal value.
Crossover from Fermi Liquid to Multichannel Luttinger Liquid in High-Mobility Quantum Wires
Mitin, Vladimir
Crossover from Fermi Liquid to Multichannel Luttinger Liquid in High-Mobility Quantum Wires M. Bell disordered Fermi liquid to a multichannel Luttinger liquid. DOI: 10.1103/PhysRevLett.104.046805 PACS numbers- sence of disorder, interacting electrons in quasi-1D con- ductors are often described by the Luttinger
Transverse electric field in a mesoscopic Luttinger-liquid ring
NASA Astrophysics Data System (ADS)
Šimánek, E.
1999-08-01
The electric field within a ring containing repulsively interacting electrons is estimated using the spinless Luttinger-liquid model extended to allow transverse excitations due to the radial centrifugal force. The radial voltage drop across a ring, threaded by the Aharonov-Bohm flux, consists of a flux-periodic part that is independent of the interaction, and a flux-independent part that is proportional to the square root of the inverse compressibility of the electron gas. The voltage drop obtained from perturbation theory is consistent with Bernoulli's equation.
Tunneling into a periodically modulated Luttinger liquid
Gramada, A.; Raikh, M.E. [Department of Physics, University of Utah, Salt Lake City, Utah 84112 (United States)] [Department of Physics, University of Utah, Salt Lake City, Utah 84112 (United States)
1997-01-01
We study the tunneling into the edge of the Luttinger liquid with a periodically modulated concentration of electrons. It is shown that the modulation, by causing a gap in the spectrum of plasmons, leads to an additional anomaly in the density of states at a frequency corresponding to the center of the gap. The shape of the anomaly depends strongly on the {ital phase} of the modulation. The sensitivity to the phase is related to the plasmon mode, localized at the edge, its frequency lying within the gap (analog of the Tamm state for an electron in a periodic potential). {copyright} {ital 1997} {ital The American Physical Society}
Transport in double-crossed Luttinger liquids
NASA Astrophysics Data System (ADS)
Durganandini, P.; Rao, Sumathi
1999-05-01
We study transport through two Luttinger liquids (one-dimensional electrons interacting through a Coulomb repulsion in a metal) coupled together at two points. External voltage biases are incorporated through boundary conditions. We include density-density couplings as well as single-particle hops at the contacts. For weak repulsive interactions, transport through the wires remains undisturbed by the interwire couplings, which renormalize to zero. For strong repulsive interactions, the interwire couplings become strong. For symmetric barriers and no external voltage bias, a single gate voltage is sufficient to tune for resonance transmission in both wires. However, for asymmetric couplings or for finite external biases, the system is insulating.
Scanning Tunneling Microscopy of a Luttinger Liquid
NASA Astrophysics Data System (ADS)
Eggert, Sebastian
2000-05-01
Explicit predictions for scanning tunneling microscopy (STM) on interacting one-dimensional electron systems are made using the Luttinger liquid formalism. The STM current changes with the distance from an impurity or boundary in a characteristic way, which reveals the spin-charge separation and the interaction strength in the system. The current exhibits Friedel-like oscillations, but also carries additional modulated behavior as a function of voltage and distance, which shows the spin-charge separation in real space. Moreover, very close to the boundary the current is strongly reduced, which is an indication of the interaction strength in the system.
Scanning tunneling microscopy of a luttinger liquid
Eggert
2000-05-01
Explicit predictions for scanning tunneling microscopy (STM) on interacting one-dimensional electron systems are made using the Luttinger liquid formalism. The STM current changes with the distance from an impurity or boundary in a characteristic way, which reveals the spin-charge separation and the interaction strength in the system. The current exhibits Friedel-like oscillations, but also carries additional modulated behavior as a function of voltage and distance, which shows the spin-charge separation in real space. Moreover, very close to the boundary the current is strongly reduced, which is an indication of the interaction strength in the system. PMID:10990699
Current-carrying states and Luttinger-liquid behavior in the spin-1/2 [ital XXZ] linear chain
Gomez-Santos, G. (Departamento de Fisica de la Materia Condensada, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain))
1992-12-01
Recent Bethe-ansatz results for the spin-1/2 [ital XXZ] model in a ring with a magnetic flux are used to identify current-carrying states and interpreted in terms of Haldane's Luttinger-liquid theory. The velocity associated with these current excitations in a Luttinger-liquid picture is extracted and compared with the velocities corresponding to charge and sound-wave excitations. The validity of the scaling relation between velocities predicted by Luttinger-liquid theory is confirmed from exact, independent evaluation of the three velocities.
Decoherence of Schrödinger cat states in a Luttinger liquid
NASA Astrophysics Data System (ADS)
Degiovanni, P.; Peysson, S.
2000-10-01
Schrödinger cat states built from quantum superpositions of left or right Luttinger fermions located at different positions in a spinless Luttinger liquid are considered. Their decoherence rates are computed within the bosonization approach, using as environments the quantum electromagnetic field or two- or three-dimensional acoustic phonon baths. Emphasis is put on the differences between the electromagnetic and acoustic environments.
Quantum wires as Luttinger liquids: experiment
NASA Astrophysics Data System (ADS)
Wegscheider, Werner; Rother, Martin; Ertl, Frank; Deutschmann, Rainer A.; Bichler, Max; Abstreiter, Gerhard
The low-temperature ballistic transport properties of quantum wires prepared by the cleaved edge overgrowth method in the GaAs/AlGaAs material system are presented. As the Fermi energy in these one-dimensional (1D) systems is varied by application of a gate voltage a series of quantized conductance plateaus is observed. The plateau values significantly deviate from integer multiples of 2·e 2 /h and show a power law increase with increasing temperature as predicted by Luttinger liquid (LL) theory. The characteristic power law scaling exponent is obtained as a function of the Fermi energy and the number of occupied 1D subbands. From nonlinear current-voltage characteristics across the quantum wires independent LL power law scaling exponents can be deduced. The latter are found to be consistent with those obtained from temperature dependent measurements. In order to rule out contact effects as the only origin of the observed deviations we have investigated a series of quantum wires of different lengths and find quenching of the Luttinger liquid behavior as the wire length is increased. This observation is in agreement with a detailed analysis of reproducable conductance fluctuations which are superimposed on the conductance plateaus.
Brownian scattering of a spinon in a Luttinger liquid
NASA Astrophysics Data System (ADS)
Rieder, M.-T.; Levchenko, A.; Micklitz, T.
2014-12-01
We consider strongly interacting one-dimensional electron liquids where elementary excitations carry either spin or charge. At small temperatures a spinon created at the bottom of its band scatters off low-energy spin and charge excitations and follows the diffusive motion of a Brownian particle in momentum space. We calculate the mobility characterizing these processes and show that the resulting diffusion coefficient of the spinon is parametrically enhanced at low temperatures compared to that of a mobile impurity in a spinless Luttinger liquid. We briefly discuss that this hints at the relevance of spin in the process of equilibration of strongly interacting one-dimensional electrons, and comment on implications for transport in clean single-channel quantum wires.
Luttinger-liquid instability in the one-dimensional [ital t]-[ital J] model
Hellberg, C.S.; Mele, E.J. (Department of Physics, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6396 (United States))
1993-07-01
We study the [ital t]-[ital J] model in one dimension by numerically projecting the true ground state from a Luttinger-liquid trial wave function. We find the model exhibits Luttinger-liquid behavior for most of the phase diagram in which interaction strength and density are varied. However, at small densities and high interaction strengths a new phase with a gap to spin excitations and enhanced superconducting correlations is found. We show that this phase is a Luther-Emery liquid and study its correlation functions.
Properties of superconductor-Luttinger-liquid hybrid systems
NASA Astrophysics Data System (ADS)
Fazio, Rosario; Hekking, F. W. J.; Odintsov, A. A.; Raimondi, R.
1999-05-01
In this paper, we review some recent results concerning the physics of superconductor-Luttinger-liquid proximity systems. We discuss both equilibrium (the pair amplitude, Josephson current, and the local density of states) and nonequilibrium (the subgap current) properties.
Driven Spin-Boson Luttinger Liquids
Andreas Kurcz; Juan Jose Garcia-Ripoll; Alejandro Bermudez
2014-11-27
We introduce a lattice model of interacting spins and bosons that leads to Luttinger-liquid physics, and allows for quantitative tests of the theory of bosonization by means of trapped-ion or superconducting-circuit experiments. By using a variational bosonization ansatz, we calculate the power-law decay of spin and boson correlation functions, and study their dependence on a single tunable parameter, namely a bosonic driving. For small drivings, Matrix-Product-States (MPS) numerical methods are shown to be efficient and validate our ansatz. Conversely, even static MPS become inefficient for large-driving regimes, such that the experiment can potentially outperform classical numerics, achieving one of the goals of quantum simulations.
Trapped one-dimensional Bose gas as a Luttinger liquid
NASA Astrophysics Data System (ADS)
Monien, H.; Linn, M.; Elstner, N.
1998-11-01
The low-energy fluctuations of a trapped, interacting quasi-one-dimensional Bose gas are studied. Our considerations apply to experiments with highly anisotropic traps. We show that under suitable experimental conditions the system can be described as a Luttinger liquid. This implies that the correlation function of the bosons decays algebraically, preventing Bose-Einstein condensation. At significantly lower temperatures a finite-size gap destroys the Luttinger liquid picture and Bose-Einstein condensation is again possible.
Where is the luttinger liquid in one-dimensional semiconductor quantum wire structures?
Wang; Millis; Das Sarma S
2000-11-20
We present the theoretical basis for analyzing resonant Raman scattering experiments in one-dimensional systems described by the Luttinger-liquid fixed point. We make experimentally testable predictions for distinguishing Luttinger liquids from the Fermi liquid and argue that presently available quantum wire systems are not in the regime where Luttinger-liquid effects are important. PMID:11082598
Where is the Luttinger Liquid in One-Dimensional Semiconductor Quantum Wire Structures?
NASA Astrophysics Data System (ADS)
Wang, D. W.; Millis, A. J.; Das Sarma, S.
2000-11-01
We present the theoretical basis for analyzing resonant Raman scattering experiments in one-dimensional systems described by the Luttinger-liquid fixed point. We make experimentally testable predictions for distinguishing Luttinger liquids from the Fermi liquid and argue that presently available quantum wire systems are not in the regime where Luttinger-liquid effects are important.
Exact results for the Kondo effect in a Luttinger liquid
Schiller, A.; Ingersent, K. (Department of Physics, University of Florida, 215 Williamson Hall, Gainesville, Florida 32611 (United States))
1995-02-15
The Kondo effect in a Luttinger liquid composed of right-moving, spin-up electrons and left-moving, spin-down electrons is mapped exactly onto the Kondo effect in a Fermi liquid. The transformation generates anisotropy in the exchange coupling, which explains the two most notable features of the Kondo effect in a full Luttinger liquid: the quenching of the impurity moment for ferromagnetic, as well as antiferromagnetic, exchange and a power-law dependence of the Kondo temperature on the exchange coupling. Impurity contributions to the low-energy thermodynamics have the same temperature dependence as in a Fermi liquid.
Josephson current and proximity effect in Luttinger liquids
Maslov, D.L. [Department of Physics and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)] [Department of Physics and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States); [Institute for Microelectronics Technology, Academy of Sciences of the Russian Federation, Chernogolovka, 142432 (Russia); Stone, M. [Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)] [Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States); Goldbart, P.M. [Department of Physics, Materials Research Laboratory, and Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)] [Department of Physics, Materials Research Laboratory, and Beckman Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States); Loss, D. [Department of Physics, Simon Fraser University, Burnaby, British Columbia, V5A 1S6 (CANADA)] [Department of Physics, Simon Fraser University, Burnaby, British Columbia, V5A 1S6 (CANADA)
1996-01-01
A theory describing a one-dimensional Luttinger liquid in contact with a superconductor is developed. Boundary conditions for the fermion fields describing Andreev reflection at the contacts are derived and used to construct a bosonic representation of the fermions. The Josephson current through a superconductor/Luttinger liquid/superconductor junction is considered for both perfectly and poorly transmitting interfaces. In the former case, the Josephson current at low temperatures is found to be essentially unaffected by electron-electron interactions. In the latter case, significant renormalization of the Josephson current occurs. The profile of the (induced) condensate wave function in a semi-infinite Luttinger liquid in contact with a superconductor is shown to decay as a power law, the exponent depending on the sign and strength of the interactions. In the case of repulsive (attractive) interactions the decay is faster (slower) than in their absence. An equivalent method of calculating the Josephson current through a Luttinger liquid, which employs the bosonization of the system as a whole (i.e., superconductor, as well as Luttinger liquid) is developed and shown to give the results equivalent to those obtained via boundary conditions describing Andreev reflection. {copyright} {ital 1996 The American Physical Society.}
Boyer, Edmond
Screening of a Luttinger liquid wire by a scanning tunneling microscope tip: II. Transport the effect of an electrostatic coupling between a scanning tunneling microscope tip and a Luttinger liquid, the tunneling current between two Luttinger liquids is typically expressed as a convo
Luttinger-Liquid Parameter of Hubbard Chain and Hubbard Ladder
NASA Astrophysics Data System (ADS)
Sano, Kazuhiro
2000-04-01
We study the Luttinger-liquid parameter K? of the Hubbard chainand the Hubbard ladder models using the ordinary perturbation methodcombined with the Luttinger-liquid relation.According to the Luttinger-liquid relation,the critical exponent K? is related to the charge susceptibility?c and the Drude weight D by K\\sb?=\\frac{1}{2}(? ?_cD)1/2.By calculating these quantities with the perturbation method, we obtainK? on the first-order analytically and up to the second-ordernumerically.We compare these results with the results of the Bethe ansatz for theHubbard chain and those of the numerical diagonalization for the Hubbardladder.This comparision shows that the perturbation calculation of K? isreliable in the weak coupling regime.
Boundary effects on one-particle spectra of Luttinger liquids
NASA Astrophysics Data System (ADS)
Schönhammer, K.; Meden, V.; Schneider, O.; Metzner, W.; Schollwöck, U.; Gunnarsson, O.
2000-03-01
Renormalization group calculations indicate that the low-energy properties of Luttinger liquids with impurities might be similar to those of Luttinger liquids with open ends. This motivates us to study the one-particle spectral properties for a variety of models of Luttinger liquids with open boundaries. We find that for the repulsive Hubbard model with interaction U the spectral weight near the boundary is enhanced in a large energy range around the chemical potential. At smaller energies a power law suppression, predicted by bosonization, sets in. We present an analytical discussion of the crossover and show that it occurs at energies exponentially (in -1/U) close to the chemical potential. This implies that bosonization only holds on exponentially small energy scales. We argue that the crossover can also be found in other models. Our comparison with exact spectra shows that the effects of boundaries can largely be understood within the Hartree-Fock approximation.
Characterization of One-Dimensional Luttinger Liquids in Terms of Fractional Exclusion Statistics
Yong-Shi Wu; Yue Yu; Huan-Xiong Yang
2000-02-09
We develop a bosonization approach to study the low temperature properties of one-dimensional gas of particles obeying fractional exclusion statistics (FES). It is shown that such ideal gas reproduces the low-energy excitations and asymptotic exponents of a one-component Luttinger liquid (with no internal degrees of freedom). The bosonized effective theory at low energy (or temperature) is identified to a $c=1$ conformal field theory (CFT) with compactified radius determined by the statistics parameter $\\lambda$. Moreover, this CFT can be put into a form of the harmonic fluid description for Luttinger liquids, with the Haldane controlling parameter identified with the statistics parameter (of quasi-particle excitations). Thus we propose to use the latter to characterize the fixed points of 1-d Luttinger liquids. Such a characterization is further shown to be valid for generalized ideal gas of particles with mutual statistics in momentum space and for non-ideal gas with Luttinger-type interactions: In either case, the low temperature behavior is controlled by an effective statistics varying in a fixed-point line.
Quantum dissociation of an edge of a Luttinger liquid
Eugene B. Kolomeisky; Michael Timmins
2005-06-15
In a Luttinger liquid phase of one-dimensional molecular matter the strength of zero-point motion can be characterized by dimensionless De Boer's number quantifying the interplay of quantum fluctuations and two-body interactions. Selecting the latter in the Morse form we show that dissociation of the Luttinger liquid is a process initiated at the system edge. The latter becomes unstable against quantum fluctuations at a value of De Boer's number which is smaller than that of the bulk instability which parallels the classical phenomenon of surface melting.
Spin-gap phases in Tomonaga-Luttinger liquids
NASA Astrophysics Data System (ADS)
Nakamura, Masaaki; Kitazawa, Atsuhiro; Nomura, Kiyohide
1999-09-01
We give details of the analysis of critical properties of spin-gap phases in one-dimensional lattice electron models. In Tomonaga-Luttinger (TL) liquid theory, the spin-gap instability occurs when the backward scattering changes from repulsive to attractive. This transition point is shown to be equivalent to that of the level-crossing of the singlet and triplet excitation spectra, using the c=1 conformal field theory and the renormalization group. Based on this notion, the transition point between the TL liquid and the spin-gap phases can be determined with high-accuracy from the numerical data of finite-size clusters. We also discuss the boundary conditions and discrete symmetries to extract these excitation spectra. This technique is applied to the extended Hubbard model, the t-J model, and the t-J-J' model, and their phase diagrams are obtained. We also discuss the relation between our results and analytical solutions in weak-coupling and low-density limits.
Bounded Luttinger liquids as a universality class of quantum critical behavior
NASA Astrophysics Data System (ADS)
Voit, Johannes; Wang, Yupeng; Grioni, Marco
2000-03-01
We show that one-dimensional quantum systems with gapless degrees of freedom and open boundary conditions form a universality class of quantum critical behavior, which we propose to call ``bounded Luttinger liquids.'' They share the following properties with ordinary (periodic) Luttinger liquids: the absence of fermionic quasiparticle excitations, charge-spin separation, and anomalous power-law correlations with exponents whose scaling relations are parametrized by a single coupling constant per degree of freedom, K?. The values of K? are independent of boundary conditions, but the representation of the critical exponents in terms of these K?'s depends on boundary conditions. We illustrate these scaling relations by exploring general rules for boundary critical exponents derived earlier using the Bethe ansatz solution of the one-dimensional Hubbard model together with boundary conformal field theory, and the theory of Luttinger liquids in finite-size systems. We apply this theory to the photoemission properties of the organic conductors (TMTSF)2X, where TMTSF is tetramethyltetraselenafulvalene, and X=ClO9, PF6, ReO4, and discuss to what extent the assumption of finite strands with open boundaries at the sample surface can reconcile the experimental results with independent information on the Luttinger-liquid state in these materials.
Nonuniversality of the one-particle Green's function of a Luttinger liquid
NASA Astrophysics Data System (ADS)
Meden, V.
1999-08-01
The one-particle Green's function of the Tomonaga-Luttinger model for one-dimensional interacting electrons is discussed. For certain directions within the plane of space-time coordinates the exponent of the asymptotic power law decay is not given by the Luttinger liquid parameters K? and K?. The consequences for Luttinger liquids in general and their spectral properties are discussed.
Hall effect in the two-dimensional Luttinger liquid
P. Anderson
1991-01-01
The temperature dependence of the Hall effect in the normal state is a commom theme of all the cuprate superconductors and has been one of the more puzzling observations on these puzzling materials. We describe a general scheme within the Luttinger liquid theory of these two-dimensional quantum fluids which corrrelates the anomalous Hall and resistivity observations on a wide variety
Correlation functions of higher-dimensional Luttinger liquids
NASA Astrophysics Data System (ADS)
Bartosch, Lorenz; Kopietz, Peter
1999-02-01
Using higher-dimensional bosonization we study correlation functions of fermions with singular forward scattering. Following Bares and Wen [Phys. Rev. B 48, 8636 (1993)] we consider density-density interactions in d dimensions that diverge in Fourier space for small momentum transfers \\|q\\| as \\|q\\|-? with ?=2(d-1). In this case the single-particle Green's function shows Luttinger-liquid behavior. However, in contrast to d=1, in higher dimensions the singularity of the momentum distribution nk for wave vectors k close to the Fermi wave vector kF is characterized by a different exponent than the singularity of the density of states ?(?) for frequencies ? close to zero. We also calculate the irreducible polarization ?*(q,?) for \\|q\\|~2kF. Whereas in the one-dimensional Tomonaga-Luttinger model ?*(+/-2kF+q,?) exhibits anomalous scaling, we show that in d>1 the leading singular corrections cancel. Thus, even though singular density-density interactions in d>1 lead to Luttinger liquid behavior of the single-particle Green's function, gauge invariant correlation functions such as the polarization or the conductivity show conventional Fermi-liquid behavior. We discuss consequences for the effect of disorder on higher-dimensional Luttinger liquids.
Universal AC response of a 1D Luttinger liquid ring
NASA Astrophysics Data System (ADS)
Moskalets, M. V.
2000-12-01
The response of a spinless ballistic Luttinger liquid ring to an oscillating in time magnetic flux is considered in the discrete spectrum limit. The dependence of the magnitude of both AC response and the DC current on the frequency and magnitude of a magnetic flux at nonzero temperatures is calculated.
Luttinger liquid behavior in single-wall nanotubes
NASA Astrophysics Data System (ADS)
Komnik, Andrei; Egger, Reinhold
1999-09-01
Transport properties of metallic single-wall nanotubes are examined based on the Luttinger liquid theory. Focusing on a nanotube transistor setup, the linear conductance is computed from the Kubo formula using perturbation theory in the lead-tube tunnel conductances. For sufficiently long nanotubes and high temperature, phonon backscattering should lead to an anomalous temperature dependence of the resistivity.
Effect of Hund coupling on one-dimensional Luttinger liquids
NASA Astrophysics Data System (ADS)
Lee, H. C.; Eric Yang, S.-R.
2000-07-01
Two one-dimensional Luttinger liquid systems coupled by Hund coupling are studied by the renormalization-group and non-Abelian bosonization methods. It is found that the Hund coupling is always relevant irrespective of the repulsive interaction between electrons within each chain. The properties of the resulting strong coupling fixed point are discussed.
Real Space Imaging of One-Dimensional Standing Waves: Direct Evidence for a Luttinger Liquid
Jhinhwan Lee; Sebastian Eggert; H. Kim; S.-J. Kahng; H. Shinohara; Y. Kuk
2004-01-01
Electronic standing waves with two different wavelengths were directly mapped near one end of a single-wall carbon nanotube as a function of the tip position and the sample bias voltage with high-resolution position-resolved scanning tunneling spectroscopy. The observed two standing waves caused by separate spin and charge bosonic excitations are found to constitute direct evidence for a Luttinger liquid. The
Fractionalized wave packets from an artificial Tomonaga-Luttinger liquid.
Kamata, H; Kumada, N; Hashisaka, M; Muraki, K; Fujisawa, T
2014-03-01
The model of interacting fermion systems in one dimension known as a Tomonaga-Luttinger liquid (TLL) provides a simple and exactly solvable theoretical framework that predicts various intriguing physical properties. Evidence of a TLL has been observed as power-law behaviour in electronic transport on various types of one-dimensional conductor. However, these measurements, which rely on d.c. transport involving electron tunneling processes, cannot identify the long-awaited hallmark of charge fractionalization, in which an injection of elementary charge e from a non-interacting lead is divided into the non-trivial effective charge e* and the remainder, e-e* (refs 6, 7, 8). Here, we report time-resolved transport measurements on an artificial TLL composed of coupled integer quantum Hall edge channels, in which we successfully identify single charge fractionalization processes. A wave packet of charge q incident from a non-interacting region breaks up into several fractionalized charge wave packets at the edges of the artificial TLL, from which transport eigenmodes can be evaluated directly. These results are informative for elucidating the nature of TLLs and low-energy excitations in the edge channels. PMID:24509659
Magnetotunneling as a Probe of Luttinger-Liquid Behavior
NASA Astrophysics Data System (ADS)
Altland, Alexander; Barnes, C. H. W.; Hekking, F. W. J.; Schofield, A. J.
1999-08-01
A novel method for detecting Luttinger-liquid behavior is proposed. The idea is to measure the tunneling conductance between a quantum wire and a parallel two-dimensional electron system as a function of both the potential difference between them, V, and an in-plane magnetic field, B. We show that the two-parameter dependence on B and V allows for a determination of the characteristic dependence on wave vector q and frequency ? of the spectral function, ALL\\(q,?\\), of the quantum wire. In particular, the separation of spin and charge in the Luttinger liquid should manifest itself as singularities in the I- V characteristics. The experimental feasibility of the proposal is discussed.
Hall effect in the two-dimensional Luttinger liquid
Anderson, P.W. (Joseph Henry Laboratories of Physics, Jadwin Hall, Princeton University, Princeton, New Jersey (USA))
1991-10-07
The temperature dependence of the Hall effect in the normal state is a commom theme of all the cuprate superconductors and has been one of the more puzzling observations on these puzzling materials. We describe a general scheme within the Luttinger liquid theory of these two-dimensional quantum fluids which corrrelates the anomalous Hall and resistivity observations on a wide variety of both pure and doped single crystals, especially the data in the accompanying Letter of Chien, Wang, and Ong.
Transport in a one-dimensional Luttinger liquid
Matthew P. A. Fisher; Leonid I. Glazman
1996-01-01
In this paper we review recent theoretical results for transport in a one-dimensional (1d) Luttinger liquid. For simplicity, we ignore electron spin, and focus exclusively on the case of a single-mode. Moreover, we consider only the effects of a single (or perhaps several) spatially localized impurities. Even with these restrictions, the predicted behavior is very rich, and strikingly different than
Interchain conductivity of coupled Luttinger liquids and organic conductors
NASA Astrophysics Data System (ADS)
Georges, Antoine; Giamarchi, Thierry; Sandler, Nancy
2000-06-01
We reconsider the theory of dc and ac interchain conductivity in quasi-one dimensional systems. Our results are in good agreement with the measured c-axis optical conductivity of (TMTSF)2ClO4 and suggest that the c-axis dc conductivity of (TMTSF)2PF6 in the 150 K
Julius Bonart; Leticia F. Cugliandolo
2013-07-24
Recent experiments with cold atoms on the impurity motion in one-dimensional liquids of interacting bosons have revealed an interesting interplay between the polaronic impurity mass shift and the renormalization of the optical potential. We show that the influence of the external trap on the Bose gas leads to a steeper effective potential for the impurity. We propose a framework in which this potential renormalization and the mass shift can be quantitatively understood by combining a semi-classical theory of density wave excitations in the Luttinger liquid with the non equilibrium formalism of a quantum Brownian particle. The obtained theoretical results reproduce well recent experimental data.
Plasmon decay and thermal transport from spin-charge coupling in generic Luttinger liquids.
Levchenko, Alex
2014-11-01
We discuss the violation of spin-charge separation in generic nonlinear Luttinger liquids and investigate its effect on the relaxation and thermal transport of genuine spin-1/2 electron liquids in ballistic quantum wires. We identify basic scattering processes compatible with the symmetry of the problem and conservation laws that lead to the decay of plasmons into the spin modes. We derive a closed set of coupled kinetic equations for the spin-charge excitations and solve the problem of thermal conductance of interacting electrons for an arbitrary relation between the quantum wire length and spin-charge thermalization length. PMID:25415912
Detection of Spin Entanglement via Spin-Charge Separation in Crossed Tomonaga-Luttinger Liquids
NASA Astrophysics Data System (ADS)
Schroer, Alexander; Braunecker, Bernd; Levy Yeyati, Alfredo; Recher, Patrik
2014-12-01
We investigate tunneling between two spinful Tomonaga-Luttinger liquids (TLLs) realized, e.g., as two crossed nanowires or quantum Hall edge states. When injecting into each TLL one electron of opposite spin, the dc current measured after the crossing differs for singlet, triplet, or product states. This is a striking new non-Fermi liquid feature because the (mean) current in a noninteracting beam splitter is insensitive to spin entanglement. It can be understood in terms of collective excitations subject to spin-charge separation. This behavior may offer an easier alternative to traditional entanglement detection schemes based on current noise, which we show to be suppressed by the interactions.
LETTER TO THE EDITOR: Fractons and Luttinger liquids
NASA Astrophysics Data System (ADS)
da Cruz, Wellington
2000-11-01
We consider the concept of fractons as particles or quasiparticles which obey a specific fractal statistics in connection with a one-dimensional Luttinger liquid theory. We obtain a dual statistics parameter tilde-nu = ? + 1 which is identified with the controlling parameter e-2? of the Luttinger model. In this way, a bosonic system characterized by a fractal index if[h] = if[2] = 1 is considered in a conformal field theory with central charge c[? = 0] = 1 = if[2] with a compactified radius R = 1 tilde-nu 1/2 = 1. Thus, we have a mapping of a bosonic theory to a fermionic one and vice versa, i.e. the duality symmetry tilde h = 3-h of the universal class h of fractons defined in the interval 1
Luttinger-liquid behavior of one-dimensional 3He
NASA Astrophysics Data System (ADS)
Astrakharchik, G. E.; Boronat, J.
2014-12-01
The ground-state properties of one-dimensional 3He are studied using quantum Monte Carlo methods. The equation of state is calculated in a wide range of physically relevant densities and is well interpolated by a power-series fit. The Luttinger liquid theory is found to describe the long-range properties of the correlation functions. The density dependence of the Luttinger parameter is explicitly found, and interestingly it shows a nonmonotonic behavior. Depending on the density, the static structure factor can be a smooth function of the momentum or might contain a peak of a finite or infinite height. Although no phase transitions are present in the system, we identify a number of physically different regimes, including an ideal Fermi gas, a "Bose gas." a "super-Tonks-Girardeau" regime, and a "quasicrystal." The obtained results are applicable to unpolarized, partially, or fully polarized 3He.
Phase transitions for a collective coordinate coupled to Luttinger liquids.
Horovitz, Baruch; Giamarchi, Thierry; Le Doussal, Pierre
2013-09-13
We study various realizations of collective coordinates, e.g., the position of a particle, the charge of a Coulomb box, or the phase of a Bose or a superconducting condensate, coupled to Luttinger liquids with N flavors. We find that for a Luttinger parameter (1/2)
Phase Transitions for a Collective Coordinate Coupled to Luttinger Liquids
NASA Astrophysics Data System (ADS)
Horovitz, Baruch; Giamarchi, Thierry; Le Doussal, Pierre
2013-09-01
We study various realizations of collective coordinates, e.g., the position of a particle, the charge of a Coulomb box, or the phase of a Bose or a superconducting condensate, coupled to Luttinger liquids with N flavors. We find that for a Luttinger parameter (1/2)
Nonequilibrium dc noise in a Luttinger liquid with an impurity
Fendley, P.; Saleur, H. [Department of Physics, University of Southern California, Los Angeles, California 90089-0484 (United States)] [Department of Physics, University of Southern California, Los Angeles, California 90089-0484 (United States)
1996-10-01
We compute exactly the nonequilibrium dc noise in a Luttinger liquid with an impurity and an applied voltage. By generalizing Landauer transport theory for Fermi liquids to interacting, integrable systems, we relate this noise to the density fluctuations of quasiparticles. We then show how to compute these fluctuations using the Bethe ansatz. The nontrivial density correlations from the interactions result in a substantial part of the nonequilibrium noise. The final result for the noise is a scaling function of the voltage, temperature, and impurity coupling. It may eventually be observable in tunneling between edges of a fractional quantum Hall effect device. {copyright} {ital 1996 The American Physical Society.}
One-dimensional fermions with neither Luttinger-liquid nor Fermi-liquid behavior.
Rozhkov, A V
2014-03-14
It is well known that, generically, one-dimensional interacting fermions cannot be described in terms of a Fermi liquid. Instead, they present a different phenomenology, that of a Tomonaga-Luttinger liquid: the Landau quasiparticles are ill defined, and the fermion occupation number is continuous at the Fermi energy. We demonstrate that suitable fine tuning of the interaction between fermions can stabilize a peculiar state of one-dimensional matter, which is dissimilar to both Tomonaga-Luttinger and Fermi liquids. We propose to call this state a quasi-Fermi liquid. Technically speaking, such a liquid exists only when the fermion interaction is irrelevant (in the renormalization group sense). The quasi-Fermi liquid exhibits the properties of both a Tomonaga-Luttinger liquid and a Fermi liquid. Similar to a Tomonaga-Luttinger liquid, no finite-momentum quasiparticles are supported by the quasi-Fermi liquid; on the other hand, its fermion occupation number demonstrates a finite discontinuity at the Fermi energy, which is a hallmark feature of a Fermi liquid. A possible realization of the quasi-Fermi liquid with the help of cold atoms in an optical trap is discussed. PMID:24679312
Luttinger liquid behavior in low-dimensional systems
NASA Astrophysics Data System (ADS)
Sandler, Nancy Patricia
The purpose of this thesis is the study of different low-dimensional systems displaying the physical properties of Luttinger liquids (LL). In recent years, the LL model has been successfully applied to understand the transport properties, and recently noise measurements, of low-dimensional electronic systems. In this thesis, I focus on quantum wires (QW) and two-dimensional systems exhibiting the fractional quantum Hall effect (FQHE) as two different examples of systems showing Luttinger liquid behavior. In the case of QW, I analyze the effect of the dimensionality crossover on the finite temperature conductance in weakly disordered quantum wires. I show that although the quasi-one-dimensional QW exhibits a typical Luttinger liquid behavior for a small number of channels in the wire, the well-established Fermi liquid picture sets in when the number of channels increases. As another example of LL behavior, I study junctions between fractional quantum Hall (FQH) systems with different filling fractions. These junctions display a rich and interesting array of new physics. For example, I show that, by analyzing the scattering processes at the junction site, processes analogous to Andreev reflection present in superconductor/normal metal junctions are also present in the FQH junctions. I also analyze the noise spectrum of FQH junctions, and show that the scale of the noise spectrum is determined by the conductance of the junction. Furthermore, I discuss the implications of these results on the interpretation of recent experiments in terms of quasiparticles with fractional charge. Finally, I introduce the concept of generalized noise Wilson ratios as universal quotients between noise amplitudes in the thermal and shot noise regimes and discuss their experimental consequences.
Experimental evidence for resonant tunneling in a luttinger liquid
Auslaender; Yacoby; de Picciotto R; Baldwin; Pfeiffer; West
2000-02-21
We have measured the low-temperature conductance of a one-dimensional island embedded in a single mode quantum wire. The quantum wire is fabricated using the cleaved edge overgrowth technique and the tunneling is through a single state of the island. Our results show that while the resonance line shape fits the derivative of the Fermi function the intrinsic linewidth decreases in a power law fashion as the temperature is reduced. This behavior agrees quantitatively with Furusaki's model for resonant tunneling in a Luttinger liquid. PMID:11017620
Tunneling between two luttinger liquids induced by a driving field.
Schmeltzer, D
2000-11-01
Tunneling between two Luttinger liquids driven by a time-dependent field with a frequency f is investigated using the zero-mode bosonization. We show that inclusion of the zero modes is essential in order to obtain correct results in the limit L(T)/L>1 ( L is the channel length and L(T) is the thermal length). We find that the tunneling current is quantized in units of "ef" and takes the form I approximately ef SUM(n = 1)(infinity)delta[mu(F)-2pi / LvPlanck's over 2pi(n-1 / 2)]. PMID:11056642
Conservation laws and bosonization in integrable Luttinger liquids
Carmelo, J.M.P.; Castro Neto, A.H.; Campbell, D.K. (Instituto de Ciencia de Materiales, Consejo Superior de Investigaciones Cientificas, Cantoblanco, SP-28949 Madrid (Spain) Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801-3080 (United States))
1994-08-15
We examine and explain the Luttinger-liquid character of models solvable by the Bethe ansatz by introducing a suitable bosonic operator algebra. In the case of the Hubbard chain, this involves two bosonic algebras which apply to [ital all] values of [ital U], electronic density, and magnetization. Only at zero magnetization does [ital not] lead to the usual charge-spin separation. We show that our pseudoparticle'' operator approach clarifies, unifies, and extends several recent results, including the existence of independent right and left equations of motion and the concept of pseudoparticle'' (also known as Bethe quasiparticle'').
Luttinger-liquid state of the zigzag double chain
NASA Astrophysics Data System (ADS)
Müller, T. F. A.; Rice, T. M.
1999-07-01
The zigzag double chain is investigated using Lanczos techniques. The weak-coupling limit is similar to that of a ladder system which is known to have a spin gap at half-filling at all coupling strengths. But the half-filled zigzag system is gapless at strong coupling. The question whether a spin gap occurs upon doping is investigated. It is shown that the doped zigzag chain is a Luttinger liquid in which the holes repel each other. The criterion is based on exact diagonalization techniques for open shell boundary conditions. As a further corroboration, the hole-hole and the hole-spin correlations are also computed.
Experimental Evidence for Resonant Tunneling in a Luttinger Liquid
NASA Astrophysics Data System (ADS)
Auslaender, O. M.; Yacoby, A.; de Picciotto, R.; Baldwin, K. W.; Pfeiffer, L. N.; West, K. W.
2000-02-01
We have measured the low-temperature conductance of a one-dimensional island embedded in a single mode quantum wire. The quantum wire is fabricated using the cleaved edge overgrowth technique and the tunneling is through a single state of the island. Our results show that while the resonance line shape fits the derivative of the Fermi function the intrinsic linewidth decreases in a power law fashion as the temperature is reduced. This behavior agrees quantitatively with Furusaki's model for resonant tunneling in a Luttinger liquid.
Potential scattering in a Luttinger liquid: weak versus strong correlations
NASA Astrophysics Data System (ADS)
Sa, Debanand
1999-12-01
The effect of a scalar impurity in Luttinger liquid is analysed. In the weak Coulomb correlation limit, the scenario presented by Oreg and Finkel'stein seems to be correct, where the problem resembles the physics of Kondo resonance. On the contrary, we propose an emergence of new physics when the correlation energy is larger than the Kondo scale, i.e. the resonance breaks, but still either the left or the right moving electron might get localised near the impurity site, giving rise to a local moment and hence a Curie-like impurity susceptibility in the system.
Applying voltage sources to a Luttinger liquid with arbitrary transmission
NASA Astrophysics Data System (ADS)
Egger, Reinhold; Grabert, Hermann
1998-10-01
The Landauer approach to transport in mesoscopic conductors has been generalized to allow for strong electronic correlations in a single-channel quantum wire. We describe in detail how to account for external voltage sources in adiabatic contact with a quantum wire containing a backscatterer of arbitrary strength. Assuming that the quantum wire is in the Luttinger liquid state, voltage sources lead to radiative boundary conditions applied to the displacement field employed in the bosonization scheme. We present the exact solution of the transport problem for arbitrary backscattering strength at the special Coulomb interaction parameter g=1/2.
Tunneling between Two Luttinger Liquids Induced by a Driving Field
NASA Astrophysics Data System (ADS)
Schmeltzer, D.
2000-11-01
Tunneling between two Luttinger liquids driven by a time-dependent field with a frequency f is investigated using the zero-mode bosonization. We show that inclusion of the zero modes is essential in order to obtain correct results in the limit LT/L>>1 ( L is the channel length and LT is the thermal length). We find that the tunneling current is quantized in units of `` ef'' and takes the form I~efn = 1??[?F-2?Lv?\\(n-12\\)].
Boundary effects on one-particle spectra of Luttinger liquids
NASA Astrophysics Data System (ADS)
Schönhammer, K.; Meden, V.; Metzner, W.; Schollwöck, U.; Gunnarsson, O.
2000-02-01
We calculate one-particle spectra for a variety of models of Luttinger liquids with open boundary conditions. For the repulsive Hubbard model, the spectral weight close to the boundary is enhanced in a large energy range around the chemical potential. A power-law suppression, previously predicted by bosonization, only occurs after a crossover at energies very close to the chemical potential. Our comparison with exact spectra shows that the effects of boundaries can partly be understood within the Hartree-Fock approximation.
Experimental evidence for resonant tunneling in a luttinger liquid.
Auslaender, O M; Yacoby, A; de Picciotto, R; Baldwin, K W; Pfeiffer, L N; West, K W
2000-02-21
We have measured the low-temperature conductance of a one-dimensional island embedded in a single mode quantum wire. The quantum wire is fabricated using the cleaved edge overgrowth technique and the tunneling is through a single state of the island. Our results show that while the resonance line shape fits the derivative of the Fermi function the intrinsic linewidth decreases in a power law fashion as the temperature is reduced. This behavior agrees quantitatively with Furusaki's model for resonant tunneling in a Luttinger liquid. PMID:21923208
Multipartite states and Luttinger liquids of composite fermions
NASA Astrophysics Data System (ADS)
Ganesh Jaya, Sreejith
Materials exhibiting exotic quantum phenomena at a macroscopic level are of great interest because of its intrinsic value to Physics, and also because of its potential applications in technology. Strongly correlated electronic systems form interesting examples of these. Exploring them calls for a good understanding of its physics, and development of new tools that are applicable to their analysis. Robustness of the fractional quantum Hall effect (FQHE) makes it an ideal stage to study strongly correlated electron systems. The complexity of the FQHE problem stems directly from the strong interactions between the constituent particles and not from the specific nature of the material it is implemented in. This work attempts to gain a theoretical description of some of the less understood aspects of FQHE. FQHE in the lowest Landau level is well understood using the theory of weakly interacting emergent particles called composite fermions. Composite fermions formed in the second Landau level however appear to be strongly interacting. Of particular interest is the FQHE at 2 + 1/2 filling fraction, where the many body ground state is believed to be described by a paired state of composite fermions, represented by the Pfaffian wavefunction. Based on predicted properties of its excitations, there has been proposals for implementing topological quantum computations in this system. However a good understanding of the nature of these excitations is still lacking. This thesis introduces a class of many body wavefunctions called "bipartite composite fermion states" that provide a unified description of all excitations of the paired state at 5/2. In the bipartite composite fermion (BCF) picture, constituent composite fermions split into two partitions which are correlated to each other. Within each partition, they fill the lowest composite fermion Landau level of its partition. Properties of the BCF state can now be related to the properties of the individual partitions, which are well understood in terms of the composite fermion theory. In particular, we show that the excitations of BCF states are obtained by creating excitations in the individual partitions. The paired state with odd number of composite fermions should have an unpaired composite fermion. The BCF model predicts that this unpaired composite fermion behaves as an exciton in the quasiparticle and quasihole are in separate partitions. We confirm this prediction numerically in finite size systems. Generalizations of bipartite composite fermion functions to other filling fractions especially 2 + 4/7 and 2 + ? are also studied. Idea of bipartite composite fermions can be generalized to the case of more partitions. Specifically, we look at tripartite composite fermion states which are similar to the bipartite states, except that these have three correlated partitions instead of two. Tripartite states have a filling fraction of ? = ?, and its particle hole conjugate is a candidate wavefunction for describing the ? = 2 + ? FQHE. Numerical comparisons of these "multipartite" composite fermion states with exact spectrum of finite systems show that these states give a very good description of the low energy spectra of the corresponding systems. Another interesting aspect of the FQH system is the realization of a chiral Luttinger liquid at the edge of an incompressible state. Effective field theory description of the system makes a non-trivial prediction that tunnelling exponents, which can be experimentally measured, are quantized. Starting from the composite fermion theory, we develop a microscopic model for the edge of the ? = ? filling fraction. The ? edge has composite fermions occupying lowest two composite fermion Landau levels each of which contributes to the edge excitations. The existence of two modes causes the edge spectrum to split into quasi-degenerate sectors of states with each sector representing a specific distribution of the composite fermions in the two levels. Calculations show that in the low energy limit, an electron tunnellin
Bound-state instability of the chiral Luttinger liquid in one dimension
NASA Astrophysics Data System (ADS)
Ho, A. F.; Coleman, P.
2000-07-01
We have developed a ``bootstrap'' method for solving a class of interacting one-dimensional chiral fermions. The conventional model for interacting right-moving electrons with spin has an SO(4) symmetry, and can be written as four interacting Majorana fermions, each with the same velocity. We have found a method for solving some cases when the velocities of these Majorana fermions are no longer equal. We demonstrate in some detail the remarkable result that corrections to the skeleton self-energy identically vanish for these models, and this enables us to solve them exactly. For the cases where the model can be solved by bosonization, our method can be explicitly checked. However, we are also able to solve some cases where the excitation spectrum differs qualitatively from a Luttinger liquid. Of particular interest is the so-called SO(3) model, where a triplet of Majorana fermions, moving at one velocity, interact with a single Majorana fermion moving at another velocity. Using our method we show, that a sharp bound (or antibound) state splits off from the original Luttinger-liquid continuum, cutting off the x-ray singularity to form a broad incoherent excitation with a lifetime that grows linearly with frequency.
Luttinger liquids with boundaries: Power-laws and energy scales
NASA Astrophysics Data System (ADS)
Meden, V.; Metzner, W.; Schollwöck, U.; Schneider, O.; Stauber, T.; Schönhammer, K.
2000-08-01
We present a study of the one-particle spectral properties for a variety of models of Luttinger liquids with open boundaries. We first consider the Tomonaga-Luttinger model using bosonization. For weak interactions the boundary exponent of the power-law suppression of the spectral weight close to the chemical potential is dominated by a term linear in the interaction. This motivates us to study the spectral properties also within the Hartree-Fock approximation. It already gives power-law behavior and qualitative agreement with the exact spectral function. For the lattice model of spinless fermions and the Hubbard model we present numerically exact results obtained using the density-matrix renormalization-group algorithm. We show that many aspects of the behavior of the spectral function close to the boundary can again be understood within the Hartree-Fock approximation. For the repulsive Hubbard model with interaction U the spectral weight is enhanced in a large energy range around the chemical potential. At smaller energies a power-law suppression, as predicted by bosonization, sets in. We present an analytical discussion of the crossover and show that for small U it occurs at energies exponentially (in -1/U) close to the chemical potential, i.e. that bosonization only holds on exponentially small energy scales. We show that such a crossover can also be found in other models.
Tunneling between helical Majorana modes and helical Luttinger liquids
NASA Astrophysics Data System (ADS)
Chao, Sung-Po; Schmidt, Thomas L.; Chung, Chung-Hou
2015-06-01
We propose and study the charge transport through single and double quantum point contacts setup between helical Majorana modes and an interacting helical Luttinger liquid. We show that the differential conductance decreases for stronger repulsive interactions and that the point contacts become insulating above a critical interaction strength. For a single-point contact, the differential conductance as a function of bias voltage shows a series of peaks due to Andreev reflection of electrons in the Majorana modes. In the case of two point contacts, interference phenomena make the structure of the individual resonance peaks less universal and show modulations with different separation distance between the contacts. For small separation distance, the overall features remain similar to the case of a single-point contact.
Coherence and Localization in 2D Luttinger Liquids
Anderson, P.W.; Ramakrishnan, T.V.; Strong, S.; Clarke, D.G. [Department of Physics, Jadwin Hall, Princeton University, Princeton, New Jersey 08544 (United States)] [Department of Physics, Jadwin Hall, Princeton University, Princeton, New Jersey 08544 (United States); [Department of Physics, Indian Institute of Science, Bangalore, 560 012 (India); [NEC Research, 4 Independence Way, Princeton, New Jersey 08540 (United States); [TCM, Cavendish Laboratory, Madingley Road, Cambridge, CB3 0HE (England)
1996-11-01
Recent measurements on the resistivity of (La-Sr){sub 2}CuO{sub 4} are shown to fit within the general framework of Luttinger liquid transport theory. They exhibit a crossover from the spin-charge separated {open_quote}{open_quote}holon nondrag regime{close_quote}{close_quote} usually observed, with {rho}{sub {ital ab}}{approximately}{ital T}, to a {open_quote}{open_quote}localizing{close_quote}{close_quote} regime dominated by impurity scattering at low temperature. The proportionality of {rho}{sub {ital c}} and {rho}{sub {ital ab}} and the giant anisotropy follow directly from the theory. {copyright} {ital 1996 The American Physical Society.}
Entanglement entropy between two coupled Tomonaga-Luttinger liquids
Shunsuke Furukawa; Yong Baek Kim
2013-03-07
We consider a system of two coupled Tomonaga-Luttinger liquids (TLL) on parallel chains and study the Renyi entanglement entropy $S_n$ between the two chains. Here the entanglement cut is introduced between the chains, not along the perpendicular direction as used in previous studies of one-dimensional systems. The limit $n\\to1$ corresponds to the von Neumann entanglement entropy. The system is effectively described by two-component bosonic field theory with different TLL parameters in the symmetric/antisymmetric channels as far as the coupled system remains in a gapless phase. We argue that in this system, $S_n$ is a linear function of the length of the chains (boundary law) followed by a universal subleading constant $\\gamma_n$ determined by the ratio of the two TLL parameters. The formulae of $\\gamma_n$ for integer $n\\ge 2$ are derived using (a) ground-state wave functionals of TLLs and (b) boundary conformal field theory, which lead to the same result. These predictions are checked in a numerical diagonalization analysis of a hard-core bosonic model on a ladder. Although the analytic continuation of $\\gamma_n$ to $n\\to 1$ turns out to be a difficult problem, our numerical result suggests that the subleading constant in the von Neumann entropy is also universal. Our results may provide useful characterization of inherently anisotropic quantum phases such as the sliding Luttinger liquid phase via qualitatively different behaviors of the entanglement entropy with the entanglement partitions along different directions.
The separated spin-charge Luttinger liquid in a magnetic field
NASA Astrophysics Data System (ADS)
Yang, Kaihua; Chen, Bin; Sun, Yunfeng; Han, Rushan
As well know one-dimensional Luttinger liquid includes many striking properties. In our paper, we study the question of the physical properties of the separated spin-charge Luttinger liquid in an external magnetic field (h). We include more completely interaction such forward scattering (g 2 and g 4). Charge and spin cannot completely be separated due to the effect of magnetic field. We calculated also the correlation function and manifestly show the action of the interaction parameters.
Ren, Y.; Zhang, F.C. [Department of Physics, University of Cincinnati, Cincinnati, Ohio 45221 (United States)] [Department of Physics, University of Cincinnati, Cincinnati, Ohio 45221 (United States)
1995-07-01
We generalize exact scaling relations between various correlation functions in one- and two-dimensional (2D) Luttinger liquids. This relation can be used to show that in the presence of strong antiferromagnetic fluctuation, there will be no enhancement of the superconducting instability from within the layer for a 2D Luttinger liquid. Possible relevance to high-{ital T}{sub {ital c}} superconducting cuprates is discussed.
Detection of spin entanglement via spin-charge separation in crossed Tomonaga-Luttinger liquids.
Schroer, Alexander; Braunecker, Bernd; Levy Yeyati, Alfredo; Recher, Patrik
2014-12-31
We investigate tunneling between two spinful Tomonaga-Luttinger liquids (TLLs) realized, e.g., as two crossed nanowires or quantum Hall edge states. When injecting into each TLL one electron of opposite spin, the dc current measured after the crossing differs for singlet, triplet, or product states. This is a striking new non-Fermi liquid feature because the (mean) current in a noninteracting beam splitter is insensitive to spin entanglement. It can be understood in terms of collective excitations subject to spin-charge separation. This behavior may offer an easier alternative to traditional entanglement detection schemes based on current noise, which we show to be suppressed by the interactions. PMID:25615359
Kohn-Luttinger effect in nested Fermion liquids
Hyok-Jon Kwon
1997-01-29
We study the Kohn-Luttinger effect in a two-dimensional (2D) nested Fermion liquid with a repulsive interaction via the renormalization group method and identify the resulting order parameter symmetry. Using the band structure of the 2D Hubbard model close to half-filling as a prototype, we construct an effective low-energy theory. We use multidimensional bosonization to incorporate the zero-sound channel and find marginal Fermi liquid behavior in the absence of any instability. We show an analog of the Landau theorem in nested Fermion liquids, which serves as the criterion of the BCS instability. Including repulsive or antiferromagnetic exchange interactions in the low-energy theory, we show that the $d_{x^2-y^2}$-wave BCS channel is renormalized to be the most attractive. Below half-filling, when the nesting is not perfect, there is competition between the spin-density-wave (SDW) and the BCS channels; when the SDW coupling is small enough, there occurs a $d_{x^2-y^2}$-wave superconducting instability at sufficiently low temperatures.
Exact thermodynamics and Luttinger liquid properties of the integrable t-J model
G. Juttner; A. Klumper; J. Suzuki
1996-11-08
A Trotter-Suzuki mapping is used to calculate the finite-temperature properties of the one-dimensional supersymmetric $t-J$ model. This approach allows for the exact calculation of various thermodynamical properties by means of the quantum transfer matrix (QTM). The free energy and other interesting quantities are obtained such as the specific heat and compressibility. For the largest eigenvalue of the QTM leading to the free energy a set of just two non-linear integral equations is presented. These equations are studied analytically and numerically for different particle densities and temperatures. The structure of the specific heat is discussed in terms of the elementary charge as well as spin excitations. Special emphasis is placed on the study of the low-temperature behavior confirming scaling predictions by conformal field theory and Luttinger liquid theory. To our knowledge this is the first complete investigation of a strongly correlated electron system on a lattice at finite temperature.
to -12pt [-12pt]to 16pt Rapid Note Wavefunctions for the Luttinger liquid
NASA Astrophysics Data System (ADS)
Pham, K.-V.; Gabay, M.; Lederer, P.
1999-07-01
Standard bosonization techniques lead to phonon-like excitations in a Luttinger liquid (LL), reflecting the absence of Landau quasiparticles in these systems. Yet in addition to the above excitations some LL are known to possess solitonic states carrying fractional quantum numbers (e.g. the spin 1/2 Heisenberg chain). We have reconsidered the zero modes in the low-energy spectrum of the gaussian boson LL hamiltonian both for fermionic and bosonic LL: in the spinless case we find that two elementary excitations carrying fractional quantum numbers allow to generate all the charge and current excited states of the LL. We explicitly compute the wavefunctions of these two objects and show that one of them can be identified with the 1D version of the Laughlin quasiparticle introduced in the context of the Fractional Quantum Hall effect. For bosons, the other quasiparticle corresponds to a spinon excitation. The eigenfunctions of Wen's chiral LL hamiltonian are also derived: they are quite simply the one dimensional restrictions of the 2D bulk Laughlin wavefunctions.
Impurity-induced thermopower in a Luttinger liquid wire
NASA Astrophysics Data System (ADS)
Krive, I. V.; Bogachek, E. N.; Scherbakov, A. G.; Landman, Uzi
2000-03-01
The thermopower S_L(T) of a finite Luttinger liquid (LL) wire containing an impurity and connected to leads of noninteracting electrons, is calculated. It is shown that at low temperatures T<< triangle _L~= hbar s/L (L is the length of a wire and s is the plasmon velocity in the LL) S_L(T) is described by a Mott-type formula. However at ''high'' temperatures triangle _L<= T<< EF (EF is the Fermi energy) the expression for S_L(T) contains an interaction-dependent factor. For strong interelectron interaction the enhancement of the thermopower is large and it is much more pronounced for spinless electrons. The thermopower of an impurity-free multi-mode LL wire, adiabatically connected to the leads, vanishes (as a function of the gate voltage) on the conductance plateaus, and it is narrowly peaked at the conductance steps. Unlike the case of noninteracting electrons the thermopower peaks are very sharp and practically temperature independent.
Non-equilibrium quantum noise in chiral Luttinger liquids
C. de C. Chamon; D. E. Freed; X. G. Wen
1995-07-18
We study non-equilibrium noise in Chiral Luttinger Liquids using the Landauer-Buttiker Scattering approach, obtaining the current/voltage noise spectrum for a four-terminal measurement scheme. Experimental consequences of the tunneling of charges are present in the four-terminal measurement of both the low-frequency shot noise ($\\omega$ near 0), and the high-frequency Josephson noise ($\\omega$ near $\\omega_J=e^*V/\\hbar$). Within perturbation theory, an algebraic singularity is present (to all orders) at the Josephson frequency $\\omega_J=e^*V/\\hbar$, whose position depends on the charge $e^*$ of the tunneling particles, either electrons or fractionally charged quasiparticles. We show in a non-perturbative calculation for an exactly solvable point that the singularity at the quasiparticle frequency exists only in the limit of vanishing coupling, whereas the singularity at the electron frequency is present for all coupling strengths. The vanishing coupling limit corresponds to perfectly quantized Hall conductance in the case of quasiparticle tunneling between edge states in the fractional quantum Hall regime, and thus tunneling destroys the singularity at the quasiparticle frequency concomitantly with the quantized current.
Indications of a Luttinger liquid in the fractional quantum Hall regime
R. A. Webb
1996-01-01
We have studied the transmission through a point contact in a gated GaAs?AlGaAs heterostructure. At the v = 13 quantum Hall plateau measurements of the tunneling conductance exhibit non-Fermi liquid like resonance properties. The temperature dependence of the off-resonance conductances and resonance line shapes agrees with recent predictions of Luttinger liquid theory.
dc and ac Josephson effect in a superconductor{endash}Luttinger-liquid{endash}superconductor system
Fazio, R. [Institut fuer Theoretische Festkoerperphysik, Universtitaet Karlsruhe, 76128 Karlsruhe (Germany)] [Institut fuer Theoretische Festkoerperphysik, Universtitaet Karlsruhe, 76128 Karlsruhe (Germany); [Istituto di Fisica, Universita di Catania, viale A. Doria 6, 95129 Catania (Italy); Hekking, F.W. [Theoretical Physics Institute, University of Minnesota, 116 Church Street SE, Minneapolis, Minnesota 55455 (United States)] [Theoretical Physics Institute, University of Minnesota, 116 Church Street SE, Minneapolis, Minnesota 55455 (United States); Odintsov, A.A. [Department of Applied Physics, Delft University of Technology, P.O. Box 5046, 2600 GA Delft (The Netherlands)] [Department of Applied Physics, Delft University of Technology, P.O. Box 5046, 2600 GA Delft (The Netherlands); [Nuclear Physics Institute, Moscow State University, Moscow 119899 GSP (Russia)
1996-03-01
We calculate both the dc and the ac Josephson current through a 1-D system of interacting electrons, connected to two superconductors by tunnel junctions. We treat the (repulsive) Coulomb interaction in the framework of the one-channel, spin-1/2 Luttinger model. The Josephson current is obtained for two geometries of experimental relevance: a quantum wire and a ring. At T=0, the critical current is found to decay algebraically with increasing distance {ital d} between the junctions. The decay is characterized by an exponent which depends on the strength of the interaction. At finite temperatures {ital T}, lower than the superconducting transition temperature {ital T}{sub {ital c}}, there is a crossover from algebraic to exponential decay of the critical current as a function of {ital d}, at a distance of the order of {h_bar}{ital v}{sub {ital F}}/{ital k}{sub {ital BT}}. Moreover, the dependence of critical current on temperature shows nonmonotonic behavior. If the Luttinger liquid is confined to a ring of circumference {ital L}, coupled capacitively to a gate voltage and threaded by a magnetic flux, the Josephson current shows remarkable parity effects under the variation of these parameters. For some values of the gate voltage and applied flux, the ring acts as a {pi} junction. These features are robust against thermal fluctuations up to temperatures on the order of {h_bar}{ital v}{sub {ital F}}/{ital k}{sub {ital BL}}. For the wire geometry, we have also studied the ac-Josephson effect. The amplitude and the phase of the time-dependent Josephson current are affected by electron-electron interactions. Specifically, the amplitude shows pronounced oscillations as a function of the bias voltage due to the difference between the velocities of spin and charge excitations in the Luttinger liquid. Therefore, the ac-Josephson effect can be used as a tool for the observation of {ital spin}-{ital charge} separation. {copyright} {ital 1996 The American Physical Society.}
Tunneling into 1D and quasi-1D conductors and Luttinger-liquid behavior
E. B. Sonin
2001-01-01
The paper addresses the problem whether and how it is possible to detect the\\u000aLuttinger-liquid behavior from the $IV$ curves for tunneling to 1D or quasi-1D\\u000aconductors. The power-law non-ohmic $IV$ curve, which is usually considered as\\u000aa manifestation of the Luttinger-liquid behavior, can be also deduced from the\\u000atheory of the Coulomb blockaded junction between 3D conductors affected by
Phase shift, the Marshall sign, and the Luttinger-liquid behavior in one dimension
Weng, Z.Y. (Texas Center for Superconductivity and Department of Physics, University of Houston, Houston, Texas 77204-5506 (United States))
1994-11-01
The phase shift as a key concept to understand the Luttinger liquid behavior in one dimension is explored in the strong-coupling regime of the Hubbard model, where a simple charge-spin separation picture exists. We demonstrate an explicit connection between the phase shift upon doping and the Marshall sign hidden in the spin background. The obtained many-body phase-shift field reproduces the known non-Fermi-liquid behavior where the phase-shift effect also plays a crucial role to shift the Fermi surface to satisfy the Luttinger volume. The connection of the phase shift and the fractional statistics transformation is also discussed.
Evidence of Luttinger liquid behavior in GaAs//AlGaAs quantum wires
NASA Astrophysics Data System (ADS)
Rother, M.; Wegscheider, W.; Deutschmann, R. A.; Bichler, M.; Abstreiter, G.
2000-02-01
We present low-temperature measurements of the ballistic transport in high-quality quantum wires. As the Fermi energy is varied, the conductance of these wires exhibits quantized plateaus at values lower than integer multiples of 2 e2/ h. We observe Luttinger liquid power laws in the temperature dependence of the plateau conductances as well as in the non-linear current-voltage characteristics. From these power laws we extract the Luttinger liquid scaling exponent ?N as a function of the Fermi energy and the number of occupied subbands.
G. Juttner; A. Klumper; J. Suzuki
1997-11-28
We present a novel treatment of finite temperature properties of the one-dimensional Hubbard model. Our approach is based on a Trotter-Suzuki mapping utilizing Shastry's classical model and a subsequent investigation of the quantum transfer matrix. We derive non-linear integral equations for three auxiliary functions which have a clear physical interpretation of elementary excitations of spin type and charge excitations in lower and upper Hubbard bands. This allows for a transparent analytical study of certain limiting cases as well as for precise numerical investigations. We present data for the specific heat, magnetic and charge susceptibilities for various particle densities and coupling strengths U. The structure exposed by these curves is discussed in terms of the elementary charge and spin excitations. Special emphasis is placed on the study of the low-temperature behavior within our ab initio approach confirming the scaling predictions by Tomonaga-Luttinger liquid theory. In addition we make contact with the ``dressed energy'' formalism established for the analysis of ground state properties.
Direct observation of Tomonaga-Luttinger-liquid state in carbon nanotubes at low temperatures
Hiroyoshi Ishii; Hiromichi Kataura; Hidetsugu Shiozawa; Hideo Yoshioka; Hideo Otsubo; Yasuhiro Takayama; Tsuneaki Miyahara; Shinzo Suzuki; Yohji Achiba; Masashi Nakatake; Takamasa Narimura; Mitsuharu Higashiguchi; Hirofumi Namatame; Masaki Taniguchi
2003-01-01
The electronic transport properties of conventional three-dimensional metals are successfully described by Fermi-liquid theory. But when the dimensionality of such a system is reduced to one, the Fermi-liquid state becomes unstable to Coulomb interactions, and the conduction electrons should instead behave according to Tomonaga-Luttinger-liquid (TLL) theory. Such a state reveals itself through interaction-dependent anomalous exponents in the correlation functions, density
Magnetism and superconductivity in the Luttinger liquid theory of high T{sub c}
Ren, Y.; Anderson, P.W. [Princeton Univ., NJ (United States)
1992-12-01
The authors discuss the competetion and interplay of the antiferromagnetic and superconducting instabilities in the Luttinger liquid high T{sub c} theory. While providing good explanation for the experiments on the magnetic fluctuations in high T{sub c} materials, they also confirm the RVB picture of superconductivity.
Non-linear ac-transport in a Luttinger liquid with a potential barrier
NASA Astrophysics Data System (ADS)
Fechner, A.; Sassetti, M.; Kramer, B.
1999-03-01
The time- and space-dependent non-linear current response to a monochromatic ac-electric field at a tunnel barrier in a one-dimensional interacting electron system is investigated within the Luttinger liquid model. The current harmonics are studied and the corresponding emitted electromagnetic powers are calculated.
Spatial properties of nonlinear ac transport in a Luttinger liquid with an impurity
Sassetti, M. [Istituto di Fisica Ingegneria, Istituto Nazionale di Fisica della Materia, Universita di Genova, Via Dodecaneso 33, I-16146 Genova (Italy)] [Istituto di Fisica Ingegneria, Istituto Nazionale di Fisica della Materia, Universita di Genova, Via Dodecaneso 33, I-16146 Genova (Italy); Kramer, B. [I. Institut fuer Theoretische Physik, Universitaet Hamburg, Jungiusstra Se 9, D-20355 Hamburg (Germany)] [I. Institut fuer Theoretische Physik, Universitaet Hamburg, Jungiusstra Se 9, D-20355 Hamburg (Germany)
1996-08-01
The nonlinear transport in a Luttinger liquid with finite-range interaction is considered for a general time-dependent driving electric field, in the presence of an impurity. In the static limit, the nonlinear current-voltage characteristic depends only on the integral of the driving field. For a time-dependent field, a relation between the currents at different sites is derived which depends only on the nonlocal ac conductivity of the Luttinger system without impurity, but is independent of the strength and the shape of the electric field. Experimental consequences are discussed. {copyright} {ital 1996 The American Physical Society.}
Bosonization of One-Dimensional Exclusons and Characterization of Luttinger Liquids
Yong-Shi Wu; Yue Yu
1995-05-08
We achieve a bosonization of one-dimensional ideal gas of exclusion statistics $\\lambda$ at low temperatures, resulting in a new variant of $c=1$ conformal field theory with compactified radius $R=\\sqrt{1/\\lambda}$. These ideal excluson gases exactly reproduce the low-$T$ critical properties of Luttinger liquids, so they can be used to characterize the fixed points of the latter. Generalized ideal gases with mutual statistics and non-ideal gases with Luttinger-type interactions have also similar behavior, controlled by an effective statistics varying in a fixed-point line.
Fingerprints of Luttinger Liquid Behavior in GaAs/AlGaAs Quantum Wires
NASA Astrophysics Data System (ADS)
Rother, Martin; Ertl, Frank; Wegscheider, Werner; Deutschmann, Rainer A.; Bichler, Max; Abstreiter, Gerhard
2000-03-01
We present measurements of the low-temperature transport properties of GaAs/AlGaAs quantum wires fabricated by cleaved egde overgrowth. As the Fermi energy is varied, the conductance of these wires exhibits quantized plateaus at values lower than integer multiples of 2e^2/h. The plateaus show a power law dependence on temperature as predicted by Luttinger liquid theory for temperatures above approx. 1K. Below this temperature the Luttinger behavior is cut off by the finite wire length. We also observe a Luttinger liquid power law and the corresponding cut-off in the non-linear current voltage characteristics and in the temperature dependence of conductance fluctuations superimposed on the plateaus. From these measurements we consistently derive the Luttinger liquid scaling exponent as a function of the Fermi energy, the number of occupied subbands and the length of the quantum wire. The exponent stays roughly constant within each subband, but changes with the number of occupied subbands.
Spectral functions of the Luttinger liquid in a magnetic field
NASA Astrophysics Data System (ADS)
Rabello, Silvio; Si, Qimiao
2000-03-01
We study the single-particle properties of the one-dimensional Luttinger model in the presence of a magnetic field. The single-particle spectral functions are calculated and it is shown that the magnetic field induce shifts on both the spinon and holon peak positions, but with different magnitude. From these results, we discuss the possibility of using angular-resolved photoemission in a magnetic field to probe spin-charge separation.
Kondo effect in a Luttinger liquid: a two-channel Kondo fixed point is not possible
NASA Astrophysics Data System (ADS)
Le Hur, Karyn
1999-01-01
The fixed point of the two-channel Kondo (TCK) model does not respect the vacuum of the backward Kondo scattering exchange. It proves rigorously that such a solution for the Kondo effect in a Luttinger liquid is forbidden while backscattering effects are prominent. When U?0, a description of the fixed point in terms of a local Fermi-liquid is not completely satisfactory since the Wilson ratio is not universal.
Ding, Lin-Jie; Yao, Kai-Lun; Fu, Hua-Hua
2010-10-25
The thermodynamics and transport properties of strong-rail ladder systems are investigated by means of Green's function theory. It is shown that the magnetic behavior clearly manifests a typical antiferromagnetism with gapped or gapless low-lying excitations, which is in agreement with the experimental results. In addition, the temperature-field-induced phase diagram is explored, and we demonstrate a Luttinger liquid behavior in the window h(c) (marking the ending of the M=0 plateau)
Ground-state properties of one-dimensional matter and quantum dissociation of a Luttinger liquid
Eugene B. Kolomeisky; Xiaoya Qi; Michael Timmins
2002-10-27
We analyze ground-state properties of strictly one-dimensional molecular matter comprised of identical particles of mass m. Such a class of systems can be described by an additive two-body potential whose functional form is common to all substances which only differ in the energy \\epsilon and range l scales of the potential. With this choice De Boer's quantum theorem of corresponding states holds thus implying that ground-state properties expressed in appropriate reduced form are only determined by the dimensionless parameter \\lambda_{0}^{2} \\sim \\hbar^{2}/ml^{2}\\epsilon measuring the strength of zero-point motion in the system. The presence of a minimum in the two-body interaction potential leads to a many-body bound state which is a Luttinger liquid. As \\lambda_{0} increases, the asymmetry of the two-body potential causes quantum expansion, softening, and eventual evaporation of the Luttinger liquid into a gas phase. Selecting the pair interaction potential in the Morse form we analytically compute the properties of the Luttinger liquid and its range of existence. As lambda_{0} increases, the system first undergoes a discontinuous evaporation transition into a diatomic gas followed by a continuous dissociation transition into a monoatomic gas. In particular we find that spin-polarized isotopes of hydrogen and He-3 are monoatomic gases, He-4 is a diatomic gas, while molecular hydrogen and heavier substances are Luttinger liquids. We also investigate the effect of finite pressure on the properties of the liquid and monoatomic gas phases. In particular we estimate a pressure at which molecular hydrogen undergoes an inverse Peierls transition into a metallic state which is a one-dimensional analog of the transition predicted by Wigner and Huntington in 1935.
Duality of weak and strong scatterer in a Luttinger liquid coupled to massless bosons.
Yurkevich, Igor V; Galda, Alexey; Yevtushenko, Oleg M; Lerner, Igor V
2013-03-29
We study electronic transport in a Luttinger liquid with an embedded impurity, which is either a weak scatterer (WS) or a weak link (WL), when interacting electrons are coupled to one-dimensional massless bosons (e.g., acoustic phonons). We find that the duality relation, ?WS?WL=1, between scaling dimensions of the electron backscattering in the WS and WL limits, established for the standard Luttinger liquid, holds in the presence of the additional coupling for an arbitrary fixed strength of boson scattering from the impurity. This means that at low temperatures such a system remains either an ideal insulator or an ideal metal, regardless of the scattering strength. On the other hand, when fermion and boson scattering from the impurity are correlated, the system has a rich phase diagram that includes a metal-insulator transition at some intermediate values of the scattering. PMID:23581351
NASA Astrophysics Data System (ADS)
Jüttner, G.; Klümper, A.; Suzuki, J.
1999-01-01
We present results of a novel treatment of finite temperature properties of the one-dimensional Hubbard model based on a Trotter-Suzuki mapping and a subsequent investigation of the quantum transfer matrix. Data are obtained for the specific heat, magnetic and charge susceptibilities for various particle densities and coupling strengths U. Special emphasis is placed on the study of the low-temperature behavior within our ab initio approach confirming the scaling predictions by Tomonaga-Luttinger liquid theory. The physical properties at finite temperature outside the universal Tomonaga-Luttinger liquid range are compared for the Hubbard and the supersymmetric tJ model. In particular the charge susceptibility shows interesting non-universal signatures.
Optimal control for unitary preparation of many-body states: application to Luttinger liquids
Armin Rahmani; Claudio Chamon
2011-05-27
Many-body ground states can be prepared via unitary evolution in cold atomic systems. Given the initial state and a fixed time for the evolution, how close can we get to a desired ground state if we can tune the Hamiltonian in time? Here we study this optimal control problem focusing on Luttinger liquids with tunable interactions. We show that the optimal protocol can be obtained by simulated annealing. We find that the optimal interaction strength of the Luttinger liquid can have a nonmonotonic time dependence. Moreover, the system exhibits a marked transition when the ratio $\\tau/L$ of the preparation time to the system size exceeds a critical value. In this regime, the optimal protocols can prepare the states with almost perfect accuracy. The optimal protocols are robust against dynamical noise.
NASA Astrophysics Data System (ADS)
Škori?, B.; Pruisken, A. M. M.
1999-10-01
We derive, from first principles, the complete Luttinger liquid theory of abelian quantum Hall edge states. This theory includes disorder and Coulomb interactions as well as the coupling to external electromagnetic fields. We introduce a theory of spatially separated edge modes, find an enlarged dual symmetry and obtain a complete classification of quasiparticle operators and tunneling exponents. The chiral anomaly on the edge is used to obtain unambiguously the Hall conductance. In resolving the problem of counter-flowing edge modes, we find that the long range Coulomb interactions play a fundamental role. In order to set up a theory for arbitrary ? we use the idea of a two-dimensional network of percolating edge modes. We derive an effective, single mode Luttinger liquid theory for tunneling processes into the edge which yields a continuous tunneling exponent 1/?. The network approach is also used to re-derive the instanton vacuum theory for plateau transitions.
Kondo effect in a Luttinger liquid: A boundary-conformal-field-theory approach
Durganandini, P. [Department of Physics, University of Poona, Pune 411 007 (India)] [Department of Physics, University of Poona, Pune 411 007 (India)
1996-04-01
The Kondo problem in a Luttinger liquid has been studied recently using a poor-man{close_quote}s-scaling method. Here, the problem is formulated using the recent boundary-conformal-field-theory technique, which allows us to describe the critical points exactly. We recover the results for the specific heat and susceptibility calculated for low temperatures. {copyright} {ital 1996 The American Physical Society.}
Frequency dependences in transport through a Tomonaga-Luttinger liquid wire
V. V. Ponomarenko
1996-01-01
Dynamics of one-dimensional electron transport between two reservoirs are studied based on the inhomogeneous Tomonaga-Luttinger-liquid model in the case when the effect of the electron backscattering on the impurities is negligible. The inhomogeneities of the interaction lead to a charge-wave reflection. This effect supposes a special behavior of the transport characteristics at the microwave frequencies. Different features are predicted in
Exact Nonequilibrium dc Shot Noise in Luttinger Liquids and Fractional Quantum Hall Devices
P. Fendley; A. W. W. Ludwig; H. Saleur
1995-01-01
A point contact in a Luttinger liquid couples left- and right-moving channels, producing shot noise. We calculate exactly the dc shot noise at zero temperature in the out-of-equilibrium steady state where current is flowing. Integrability ensures the existence of a quasiparticle basis where scattering is ``one by one'' off the point contact, enabling us to generalize the Landauer approach to
Evidence for Luttinger-Liquid Behavior in Crossed Metallic Single-Wall Nanotubes
B. Gao; A. Komnik; R. Egger; D. C. Glattli; A. Bachtold
2004-01-01
Transport measurements through crossed metallic single-wall nanotubes are presented. We observe a zero-bias anomaly in one tube which is suppressed by a current flowing through the other nanotube. These results are compared with a Luttinger-liquid model which takes into account electrostatic tube-tube coupling together with crossing-induced backscattering processes. Explicit solution of a simplified model is able to describe qualitatively the
Luttinger Liquid in the Core of a Screw Dislocation in Helium4
M. Boninsegni; A. B. Kuklov; L. Pollet; N. V. Prokof'Ev; B. V. Svistunov; M. Troyer
2007-01-01
On the basis of first-principles Monte Carlo simulations we find that the screw dislocation along the hexagonal axis of an hcp He4 crystal features a superfluid (at T-->0) core. This is the first example of a regular quasi-one-dimensional supersolid---the phase featuring both translational and superfluid orders, and one of the cleanest cases of a Luttinger-liquid system. In contrast, the same
Fermi-edge singularity with backscattering in the Luttinger-liquid model
Prokof'ev, N.V. (Physics Department, University of British Columbia, 6224 Agricultural Road, Vancouver, British Columbia, V6T 1Z1 (Canada))
1994-01-15
We study the response of the interacting electron gas in one-dimension (1D) to a local external potential. In the low-frequency limit the power-law singularities are essentially modified by backscattering effects which, in the case of zero forward scattering, result in the universal critical exponent depending only on the Luttinger-liquid interactions. The results obtained may be used to describe singular responses of the 1D boson chains.
Static and dynamic image potential for tunneling into a Luttinger liquid
NASA Astrophysics Data System (ADS)
Hügle, S.; Egger, R.; Grabert, H.
2000-12-01
We study electron tunneling from a tip or a lead into an interacting quantum wire described by Luttinger liquid theory. Within a WKB-type approach, the Coulomb interaction between the wire and the tunneling electrons, as well as the finite traversal time are taken into account. Although the static image potential is only logarithmically suppressed against the bare Coulomb interaction, the dynamic image potential is not strong enough to alter power-law exponents entering the tunneling density of states.
Enrico Arrigoni
1999-01-01
We consider the low-energy region of an array of Luttinger liquids coupled by a weak interchain hopping. The leading-logarithmic divergences can be resummed to all orders, within a self-consistent perturbative expansion in the hopping, in the large-dimension limit. The anomalous exponent scales to zero below the one-particle crossover temperature. As a consequence, coherent quasiparticles with finite weight appear along the
Tunneling spectroscopy of a spiral Luttinger liquid in contact with superconductors
NASA Astrophysics Data System (ADS)
Liu, Dong E.; Levchenko, Alex
2014-03-01
One-dimensional wires with Rashba spin-orbit coupling, magnetic field, and strong electron-electron interactions are described by a spiral Luttinger liquid model. We develop a theory to investigate the tunneling density of states into a spiral Luttinger liquid in contact with superconductors at its two ends. This approach provides a way to disentangle the delicate interplay between superconducting correlations and strong electron interactions. If the wire-superconductor boundary is dominated by Andreev reflection, we find that in the vicinity of the interface the zero-bias tunneling anomaly reveals a power law enhancement with the unusual exponent. This zero-bias due to Andreev reflections may coexist and thus mask possible peak due to Majorana bound states. Far away from the interface strong correlations inherent to the Luttinger liquid prevail and restore conventional suppression of the tunneling density of states at the Fermi level, which acquires a Friedel-like oscillatory envelope with the period renormalized by the strength of the interaction. D.E.L. was supported by Michigan State University and in part by ARO through Contract No. W911NF-12-1-0235. A.L. acknowledges support from NSF under Grant No. PHYS-1066293, and the hospitality of the Aspen Center for Physics.
H. Rauf; T. Pichler; M. Knupfer; J. Fink; H. Kataura
2004-01-01
We report on the first direct observation of a transition from a Tomonaga-Luttinger liquid to a Fermi-liquid behavior in potassium-intercalated mats of single-wall carbon nanotubes. Using high resolution photoemission spectroscopy, an analysis of the spectral shape near the Fermi level reveals a Tomonaga-Luttinger liquid power law scaling in the density of states for the pristine sample and for low dopant
Kohn-Luttinger Effect in a Two-dimensional Dense Fermi Liquid with Coulomb Repulsion.
NASA Astrophysics Data System (ADS)
Galitski, Victor
2000-03-01
In 1965 Kohn and Luttinger showed that a Fermi-liquid is unstable against the superconductive transition even in the case of purely repulsive interaction among particles. It has been shown that there is a pairing due to this singularity at least for large orbital momenta l. Recent experiments on 2-D electron gas have renewed interest in Kohn-Luttinger effect. In this work we consider the case of 2-D dense Fermi-liquid with pure Coulomb interaction among electrons. We show that such a system becomes superconductive at very low temperatures. Following Chubukov [2], we calculate the singular part of the scattering amplitude ?(q) up to the third order in the perturbation theory. To calculate diagrams we use screened Coulomb interaction. This allows us to avoid divergencies of the scattering amplitude appearing due to the Coulomb potential being long-range and also makes the problem similar to the one for the dilute Fermi-gas with short-range repulsive forces. The desired singularity ?^sing(q) ~ ?( 2 pF )^2 -q^2 appears in the third order perturbation theory and allows us to find the transition temperature Tc for large l. [1] W. Kohn and J. H. Luttinger, Phys. Rev. Lett. 15, 524 (1965), [2] A. Chubukov, Phys. Rev. B 48, 1097 (1993).
Luttinger-liquid behavior and superconducting correlations in {ital t}-{ital J} ladders
Hayward, C.A.; Poilblanc, D. [Laboratoire de Physique Quantique, Universite Paul Sabatier, 31062 Toulouse (France)] [Laboratoire de Physique Quantique, Universite Paul Sabatier, 31062 Toulouse (France)
1996-05-01
The low-energy behavior of the isotropic {ital t}-{ital J} ladder system is investigated using exact diagonalization techniques, specifically finding the Drude weight, the charge velocity, and the compressibility. By applying the ideas of Luttinger-liquid theory, we determine the correlation exponent {ital K}{sub {rho}} which defines the behavior of the long-range correlations in the system. The boundary to phase separation is determined and a phase diagram is presented. At low electron density, a Tomonaga-Luttinger-like phase is stabilized while at higher electron densities a gapped phase with power law pairing correlations is stabilized: A large region of this gapped phase is found to exhibit dominant superconducting correlations. {copyright} {ital 1996 The American Physical Society.}
A unified framework for the Kondo problem and for an impurity in a Luttinger liquid
P. Fendley; F. Lesage; H. Saleur
1995-10-11
We develop a unified theoretical framework for the anisotropic Kondo model and the boundary sine-Gordon model. They are both boundary integrable quantum field theories with a quantum-group spin at the boundary which takes values, respectively, in standard or cyclic representations of the quantum group $SU(2)_q$. This unification is powerful, and allows us to find new results for both models. For the anisotropic Kondo problem, we find exact expressions (in the presence of a magnetic field) for all the coefficients in the ``Anderson-Yuval'' perturbative expansion. Our expressions hold initially in the very anisotropic regime, but we show how to continue them beyond the Toulouse point all the way to the isotropic point using an analog of dimensional regularization. For the boundary sine-Gordon model, which describes an impurity in a Luttinger liquid, we find the non-equilibrium conductance for all values of the Luttinger coupling.
NASA Astrophysics Data System (ADS)
Arrigoni, Enrico
1999-07-01
We consider the low-energy region of an array of Luttinger liquids coupled by a weak interchain hopping. The leading-logarithmic divergences can be resummed to all orders, within a self-consistent perturbative expansion in the hopping, in the large-dimension limit. The anomalous exponent scales to zero below the one-particle crossover temperature. As a consequence, coherent quasiparticles with finite weight appear along the whole Fermi surface. Extending the expansion self-consistently to all orders turns out to be crucial to restore the correct Fermi-liquid behavior.
Nicole Fabbri; Milosz Panfil; David Clément; Leonardo Fallani; Massimo Inguscio; Chiara Fort; Jean-Sébastien Caux
2015-03-23
Interactions are known to have dramatic effects on bosonic gases in one dimension (1D). Not only does the ground state transform from a condensate-like state to an effective Fermi sea, but new fundamental excitations, which do not have any higher-dimensional equivalents, are predicted to appear. In this work, we trace these elusive excitations via their effects on the dynamical structure factor of 1D strongly-interacting Bose gases at low temperature. An array of 1D Bose gases is obtained by loading a $^{87}$Rb condensate in a 2D lattice potential. The dynamical structure factor of the system is probed by energy deposition through low-momentum Bragg excitations. The experimental signals are compared to recent theoretical predictions for the dynamical structure factor of the Lieb-Liniger model at $T > 0$. Our results demonstrate that the main contribution to the spectral widths stems from the dynamics of the interaction-induced excitations in the gas, which cannot be described by the Luttinger liquid theory.
NASA Astrophysics Data System (ADS)
Fabbri, N.; Panfil, M.; Clément, D.; Fallani, L.; Inguscio, M.; Fort, C.; Caux, J.-S.
2015-04-01
Interactions are known to have dramatic effects on bosonic gases in one dimension (1D). Not only does the ground state transform from a condensate like state to an effective Fermi sea, but new fundamental excitations, which do not have any higher-dimensional equivalents, are predicted to appear. In this work, we trace these elusive excitations via their effects on the dynamical structure factor of 1D strongly interacting Bose gases at low temperature. An array of 1D Bose gases is obtained by loading a 87Rb condensate in a two-dimensional lattice potential. The dynamical structure factor of the system is probed by energy deposition through low-momentum Bragg excitations. The experimental signals are compared to recent theoretical predictions for the dynamical structure factor of the Lieb-Liniger model at T >0 . Our results demonstrate that the main contribution to the spectral widths stems from the dynamics of the interaction-induced excitations in the gas, which cannot be described by the Luttinger liquid theory.
Exact nonequilibrium dc shot noise in Luttinger liquids and fractional quantum Hall devices
Fendley, P.; Ludwig, A.W.W.; Saleur, H. [Department of Physics, University of Southern California, Los Angeles, California 90089-0484 (United States)] [Department of Physics, University of Southern California, Los Angeles, California 90089-0484 (United States); [Physics Department, University of California, Santa Barbara, California 93106 (United States)
1995-09-11
A point contact in a Luttinger liquid couples left- and right-moving channels, producing shot noise. We calculate exactly the dc shot noise at zero temperature in the out-of-equilibrium steady state where current is flowing. Integrability ensures the existence of a quasiparticle basis where scattering is ``one by one`` off the point contact, enabling us to generalize the Landauer approach to shot noise to this interacting model. Experiments in a fractional quantum Hall effect device should test our results, providing a clear signal of the fractional charge of the Laughlin quasiparticles.
NASA Astrophysics Data System (ADS)
Hirai, Takashi; Kusakabe, Koichi; Tanaka, Yukio
2000-07-01
We present a theory for the Josephson effect in an unconventional superconductor/Luttinger liquid/unconventional superconductor (s/LL/s) junction where the Josephson current is carried by components injected perpendicular to the interface. We apply the bosonization method by Haldane and Maslov to the cases with arbitrary barrier height of the insulator formed between the superconductor and the LL. When superconductors on both sides have triplet symmetries, the Josephson current is enhanced at low temperatures due to the zero-energy states formed near the interface independent of the strength of electron-electron interaction and the transparency of the junction.
Breakdown of Luttinger liquid state in a one-dimensional frustrated spinless fermion model
NASA Astrophysics Data System (ADS)
Zhuravlev, A. K.; Katsnelson, M. I.
2000-06-01
The Haldane hypothesis about the universality of the Luttinger liquid (LL) behavior in conducting one-dimensional fermion systems is checked numerically for the spinless fermion model with next-nearest-neighbor interactions. It is shown that for the large enough interactions the ground state can be gapless due to frustrations but at the same time might not belong to the same universality class as a simple LL. The exponents of the correlation functions for this unusual conducting state are found numerically by a finite-size method.
Coulomb blockade effects on quantization of charge and persistent current in a Luttinger liquid ring
Sandstroem, P. [Department of Applied Physics, Chalmers University of Technology and Goeteborg University, S-412 96 Goeteborg (Sweden)] [Department of Applied Physics, Chalmers University of Technology and Goeteborg University, S-412 96 Goeteborg (Sweden); Krive, I.V. [Department of Applied Physics, Chalmers University of Technology and Goeteborg University, S-412 96 Goeteborg, Sweden, and B. Verkin Institute for Low Temperature Physics and Engineering, Academy of Sciences of Ukraine, 310164 Kharkov (Ukraine)] [Department of Applied Physics, Chalmers University of Technology and Goeteborg University, S-412 96 Goeteborg, Sweden, and B. Verkin Institute for Low Temperature Physics and Engineering, Academy of Sciences of Ukraine, 310164 Kharkov (Ukraine)
1997-06-01
We show that in a ring-shaped Luttinger liquid (LL) in contact with an electron reservoir{emdash}the electrostatic potential in the ring being controlled by a gate voltage{emdash}both the average ring charge and the persistent current in the ring are step-like functions of the gate voltage at low temperatures. The step positions are determined by the LL parameter {alpha}=v{sub F}/s, which therefore can be directly measured. We study electrons both with and without spin, taking into account long-range interactions in the ring. {copyright} 1997 Academic Press, Inc.
Luttinger liquid to Al'tshuler-Aronov transition in disordered, many-channel carbon nanotubes.
Kar, Swastik; Soldano, Caterina; Chen, Li; Talapatra, Saikat; Vajtai, Robert; Nayak, Saroj; Ajayan, Pulickel M
2009-01-27
We present a simple method to increase the conductance of individual template-grown carbon nanotubes contacted with platinum electrodes using a high-bias treatment process which decorates the nanotubes with Pt nanoclusters. The temperature dependence of conductance of the modified carbon nanotubes follows very closely a Luttinger-liquid to Al'tshuler-Aronov anomaly and reveals enhanced number of channels and decreased disorder-density compared to the pristine tubes. Low temperature magnetotransport shows evidence of Rashba spin-orbit coupling, usually absent in bare nanotubes, and a strong suppression of phase coherence at low electronic energies due to electron-electron interactions. PMID:19206268
Luttinger Liquid in the Core of a Screw Dislocation in Helium-4
Boninsegni, M. [Department of Physics, University of Alberta, Edmonton, Alberta T6G 2J1 (Canada); Kuklov, A. B. [Department of Engineering Science and Physics, CUNY, Staten Island, New York 10314 (United States); Pollet, L.; Troyer, M. [Theoretische Physik, ETH Zuerich, CH-8093 Zurich (Switzerland); Prokof'ev, N. V.; Svistunov, B. V. [Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003 (United States); Russian Research Center 'Kurchatov Institute', 123182 Moscow (Russian Federation)
2007-07-20
On the basis of first-principles Monte Carlo simulations we find that the screw dislocation along the hexagonal axis of an hcp {sup 4}He crystal features a superfluid (at T{yields}0) core. This is the first example of a regular quasi-one-dimensional supersolid--the phase featuring both translational and superfluid orders, and one of the cleanest cases of a Luttinger-liquid system. In contrast, the same type of screw dislocation in solid H{sub 2} is insulating.
Crossover from Fermi liquid to Luttinger-liquid-like behavior in the two-dimensional Hubbard model
Aristov, D.N.; Maleyev, S.V.; Yashenkin, A.G. (Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg 188350 (Russian Federation))
1993-08-01
The crossover from conventional Fermi-liquid (FL) behavior to the Luttinger-liquid-like behavior in the two-dimensional single-band small-[ital U] Hubbard model near half filling is demonstrated. The applicability of the FL picture is discussed. This crossover is reproduced in the fermionic channel of the [ital t]-[ital J] model, if the fermion-fermion interaction is taken into account. The results are in qualitative agreement with the normal-state resistivity and photoemission data on the high-[ital T][sub [ital c
Review: Luttinger or fermi liquids versus topological superconductivity
G. G. N. Angilella; N. H. March; R. Pucci; R. H. Squire
2002-01-01
Superconductors, classified by materials, embrace at least four broad groups: (i) BCS metals and alloys; (ii) heavy Fermion materials; (iii) high- T c cuprates and (some) organic compounds, and (iv) fullerides. Broadly speaking, in classes (i) and (iv), with (i) possibly embracing the recent discovery of superconductivity in MgB 2 with T c ? 40 K, electron liquids flow through
Kohn-Luttinger effect and the instability of a repulsive Fermi-liquid at T = 0
Chubukov, A.V. [Univ. of Illinois, Urbana (United States)]|[P.L. Kapitza Inst. for Physical Problems, Moscow (Russian Federation)
1992-11-01
The author considers the possibility for a pairing instability in a 2D repulsive Fermi-liquid due to the singularity in the scattering amplitude {Gamma}(q) at the momentum transfer q {approx} 2p{sub F} (Kohn-Luttinger effect). For arbitrary Fermi-liquid, {Gamma}(q) for the particles at the Fermi surface is found to have a singular part. For large 2D orbital momentum l, this term gives a dominant attractive contribution to the scattering amplitude and leads to a pairing instability in a 2D Fermi-liquid with arbitrary short-range repulsion. In the dilute limit, numerical studies show that the effect survives down to l = 1 and gives rise to a p-wave pairing. 12 refs.
Cluster Luttinger Liquids of Rydberg-dressed Atoms in Optical Lattices
Marco Mattioli; Marcello Dalmonte; Wolfgang Lechner; Guido Pupillo
2013-09-27
We investigate the zero-temperature phases of bosonic and fermionic gases confined to one dimension and interacting via a class of finite-range soft-shoulder potentials (i.e. soft-core potentials with an additional hard-core onsite interaction). Using a combination of analytical and numerical methods, we demonstrate the stabilization of critical quantum liquids with qualitatively new features with respect to the Tomonaga-Luttinger liquid paradigm. These features result from frustration and cluster formation in the corresponding classical ground-state. Characteristic signatures of these liquids are accessible in state-of-the-art experimental setups with Rydberg-dressed ground-state atoms trapped in optical lattices.
Stability of the Tomonaga-Luttinger liquid state in gamma-irradiated carbon nanotube bundles
NASA Astrophysics Data System (ADS)
Danilchenko, B. A.; Tripachko, N. A.; Voitsihovska, E. A.; Yaskovets, I. I.; Uvarova, I. Y.; Sundqvist, B.
2013-11-01
We report experimental results for the changes in conductivity of single-wall carbon nanotube bundles when irradiated by 60Co ?-rays in various environments. In the current study the samples investigated were irradiated in hermetic cells, either evacuated (0.1 Pa) or filled with hydrogen or deuterium at atmospheric pressure. In situ measurements of the resistance change as a function of irradiation dose at room temperature are presented. It was found that, for all irradiation conditions, the normalized resistance versus irradiation dose demonstrates a logarithmic behaviour. A phenomenological model for the observed dependence is derived. The current-voltage characteristics of the irradiated samples were measured in the temperature range from 4.5 to 300 K using short (10 ns) electric pulses, and the results demonstrate a scaling behaviour. This scaling occurs in the universal coordinates that correspond to the Tomonaga-Luttinger liquid concept. Our results confirm the existence of the Tomonaga-Luttinger liquid phase up to room temperature in carbon nanotubes after ?-irradiation to a dose of 5 × 107 rad in vacuum, 1.7 × 107 rad in hydrogen and 1.24 × 108 rad in deuterium.
Denlinger, J.D.; Gweon, G.; Allen, J.W.; Schlenker, C.; Hsu, L. [Randall Laboratory of Physics, University of Michigan, Ann Arbor, Michigan 48109-1120 (United States)] [Randall Laboratory of Physics, University of Michigan, Ann Arbor, Michigan 48109-1120 (United States); Olson, C.G. [Ames Laboratory, Iowa State University, Ames, Iowa 50011 (United States)] [Ames Laboratory, Iowa State University, Ames, Iowa 50011 (United States); Marcus, J. [Laboratoire d`Etudes des Proprietes Electroniques des Solides--CNRS, BP166, 38042 Grenoble Cedex (France)] [Laboratoire d`Etudes des Proprietes Electroniques des Solides--CNRS, BP166, 38042 Grenoble Cedex (France)
1999-03-01
We report the detailed non-Fermi-liquid (NFL) line shape of the dispersing excitation which defines the Fermi surface for quasi-one-dimensional Li{sub 0.9}Mo {sub 6}O{sub 17} . The properties of Li{sub 0.9}Mo {sub 6}O{sub 17} strongly suggest that the NFL behavior has a purely electronic origin. In relation to the theoretical Luttinger liquid line shape, we identify significant similarities, but also important differences. {copyright} {ital 1999} {ital The American Physical Society}
Anderson, P.W. (Joseph Henry Laboratories of Physics, Jadwin Hall, Princeton University, Princeton, NJ (USA))
1990-08-01
The resonating valence bond--Luttinger liquid theory for the high-{Tc} normal state permits some predictions about the effect of superconductivity on two measures of the one-particle Green's function: angle-resolved photoemission and tunneling for a high-{Tc}--insulator--high-{Tc} junction. These are compared to preliminary experimental data.
NASA Astrophysics Data System (ADS)
Schmeltzer, D.; Berkovits, R.
1999-03-01
A zero mode bosonization technique treatment of the Hamiltonian is applied to the calculation of the persisten current carried by a Luttinger liquid with a single impurity. Analytical expressions are obtained for the suppression of the current as function of the impurity strength and the electron-electron interaction. The expression in the weak limit is confirmed numerically.
LETTER TO THE EDITOR: Luttinger-liquid-like transport in long InSb nanowires
NASA Astrophysics Data System (ADS)
Zaitsev-Zotov, S. V.; Kumzerov, Yu A.; Firsov, Yu A.; Monceau, P.
2000-05-01
Long nanowires of degenerate semiconductor InSb in asbestos matrix (wire diameter about 50 Å, length 0.1-1 mm) have been prepared. The electrical conduction of these nanowires has been studied over a temperature range 1.5-350 K. The zero-field electrical conductance is a power function of temperature G?T? with a typical exponent ??4. Current-voltage characteristics of such nanowires are nonlinear and, at sufficiently low temperatures, follow the power law I?V?. The electrical conduction of the nanowires cannot be accounted for in terms of ordinary single-electron theories and exhibits features expected for impure Luttinger liquid (LL). For the simple approximation of an impure LL as a pure liquid broken into drops by weak links, the estimated weak-link density is around 103-104 cm-1.
Spin susceptibility of interacting electrons in one dimension: Luttinger liquid and lattice effects
NASA Astrophysics Data System (ADS)
Nélisse, H.; Bourbonnais, C.; Touchette, H.; Vilk, Y. M.; Tremblay, A.-M. S.
1999-11-01
The temperature-dependent uniform magnetic susceptibility of interacting electrons in one dimension is calculated using several methods. At low temperature, the renormalization group reaveals that the Luttinger liquid spin susceptibility $\\chi (T) $ approaches zero temperature with an infinite slope in striking contrast with the Fermi liquid result and with the behavior of the compressibility in the absence of umklapp scattering. This effect comes from the leading marginally irrelevant operator, in analogy with the Heisenberg spin 1/2 antiferromagnetic chain. Comparisons with Monte Carlo simulations at higher temperature reveal that non-logarithmic terms are important in that regime. These contributions are evaluated from an effective interaction that includes the same set of diagrams as those that give the leading logarithmic terms in the renormalization group approach. Comments on the third law of thermodynamics as well as reasons for the failure of approaches that work in higher dimensions are given.
Magnetic ac control of the spin textures in a helical Luttinger liquid
NASA Astrophysics Data System (ADS)
Dolcetto, G.; Cavaliere, F.; Sassetti, M.
2014-03-01
We demonstrate the possibility to induce and control peculiar spin textures in a helical Luttinger liquid, by means of a time-dependent magnetic scatterer. The presence of a perturbation that breaks the time-reversal symmetry opens a gap in the spectrum, inducing single-particle backscattering and a peculiar spin response. We show that in the weak backscattering regime asymmetric spin textures emerge at the left and right sides of the scatterer, whose spatial oscillations are controlled by the ratio between the magnetization frequency and the Fermi energy and by the electron interaction. This peculiar spin response marks a strong difference between helical and nonhelical liquids, which are expected to produce symmetric spin textures even in the ac regime.
A unified framework for the Kondo problem and for an impurity in a Luttinger liquid
Fendley, P.; Lesage, F.; Saleur, H. [Univ. of Southern California, Los Angeles, CA (United States)
1996-10-01
We develop a unified theoretical framework for the anisotropic Kondo model and the boundary sine-Gordon model. They are both boundary integrable quantum field theories with a quantum-group spin at the boundary which takes values, respectively, in standard or cyclic representations of the quantum group SU(2){sub q}. This unification is powerful, and allows us to find new results for both models. For the anisotropic Kondo problem, we find exact expressions (in the presence of a magnetic field) for all the coefficients in the Anderson-Yuval perturbative expansion. Our expressions hold initially in the very anisotropic regime, but we show how to continue them beyond the Toulouse point all the way to the isotropic point using an analog of dimensional regularization. The analytic structure is transparent, involving only simple poles which we determine exactly, together with their residues. For the boundary sine-Gordon model, which describes an impurity in a Luttinger liquid, we find the non-equilibrium conductance for all values of the Luttinger coupling. This is an intricate computation because the voltage operator and the boundary scattering do not commute with each other.
Effect of short-range electron correlations in dynamic transport in a Luttinger liquid
NASA Astrophysics Data System (ADS)
Sablikov, V. A.; Gindikin, Yasha
2000-05-01
The density operator in the Luttinger model consists of two components, one of which describes long-wave fluctuations and the other is related to the rapid oscillations of charge-density-wave (CDW) type, caused by short-range electron correlations. It is commonly believed, that the conductance is determined by the long-wave component. The CDW component is considered only when an impurity is present. We investigate the contribution of this component to the dynamic density response of a Luttinger liquid free from impurities. The conventional form of the CDW density operator is shown not to conserve the number of particles in the system. We propose the corrected CDW density operator devoid of this shortcoming and calculate the dissipative conductance in the case when the one-dimensional conductor is locally disturbed by a conducting probe. The contribution of CDW component to conductance is found to dominate over that of the long-wave component in the low-frequency regime.
Fernando Quijandría; Juan José García-Ripoll; David Zueco
2014-09-16
A way of constructing continuous matrix product states (cMPS) for coupled fields is presented here. The cMPS is a variational \\emph{ansatz} for the ground state of quantum field theories in one dimension. Our proposed scheme is based in the physical interpretation in which the cMPS class can be produced by means of a dissipative dynamic of a system interacting with a bath. We study the case of coupled bosonic fields. We test the method with previous DMRG results in coupled Lieb Liniger models. Besides, we discuss a novel application for characterizing the Luttinger liquid theory emerging in the low energy regime of these theories. Finally, we propose a circuit QED architecture as a quantum simulator for coupled fields.
Luttinger liquid of polarons in one-dimensional boson-fermion mixtures
L. Mathey; D. -W. Wang; W. Hofstetter; M. D. Lukin; Eugene Demler
2004-01-23
We use bosonization approach to investigate quantum phases in mixtures of bosonic and fermionic atoms confined in one dimensional optical lattices. The phase diagrams can be well understood in terms of polarons, which correspond to atoms that are "dressed" by screening clouds of the other atom species. For a mixture of single species of fermionic and bosonic atoms we find a charge density wave phase, a phase with fermion pairing, and a regime of phase separation. For a mixture of two species of fermionic atoms and one species of bosonic atoms we obtain spin and charge density wave phases, a Wigner crystal phase, singlet and triplet paired states of fermions, and a phase separation regime. Equivalence between the Luttinger liquid description of polarons and the canonical polaron transformation is established and the techniques to detect the resulting quantum phases are discussed.
Boundary Potential Effect for the Kondo Problem in a Luttinger Liquid:. Integrable Case
NASA Astrophysics Data System (ADS)
Wang, Yupeng; Jin, Duo; Pu, Fu-Cho
To study the impurity potential effect to the Kondo problem in a Luttinger liquid, we introduce a model of ferromagnetic single-impurity Kondo problem in a multi-band one-dimensional ?-potential Fermi gas, which is exactly solvable for a special Kondo coupling constant via Bethe ansatz. It is found that the boundary potential modifies the local moment seriously due to the charge-spin coupling and the strong backward scattering off the impurity, and thus strongly affects the fixed point of the system. Generally, their is a residual entropy for the ground state which depends on the strength of the boundary potential. In addition, the tunneling effect through the impurity and the breakdown of the open boundary induced by the impurity are also discussed.
Enhanced Coherence of a Quantum Doublet Coupled to Tomonaga-Luttinger Liquid Leads
Antonio Cirillo; Matteo Mancini; Domenico Giuliano; Pasquale Sodano
2011-05-29
We use boundary field theory to describe the phases accessible to a tetrahedral qubit coupled to Josephson junction chains acting as Tomonaga-Luttinger liquid leads. We prove that, in a pertinent range of the fabrication and control parameters, an attractive finite coupling fixed point emerges due to the geometry of the composite Josephson junction network. We show that this new stable phase is characterized by the emergence of a quantum doublet which is robust not only against the noise in the external control parameters (magnetic flux, gate voltage) but also against the decoherence induced by the coupling of the tetrahedral qubit with the superconducting leads. We provide protocols allowing to read and to manipulate the state of the emerging quantum doublet and argue that a tetrahedral Josephson junction network operating near the new finite coupling fixed point may be fabricated with today's technologies.
Response functions of two-coupled chains of Tomonaga-Luttinger liquids
NASA Astrophysics Data System (ADS)
Yoshioka, Hideo; Suzumura, Yoshikazu
1998-12-01
Properties of fluctuations in two chains of Tomonaga-Luttinger liquids coupled by the interchain hopping have been studied by calculating retarded response functions ? ?R( q x, q y; ?) for charge and ? ?R( q x, q y; ?) for spin where q x and q y(=0 or ?) denote the longitudinal and transverse wave vector, respectively, and ? is the frequency. We have found the notable fact that the repulsive intrachain interaction results in the clear enhancement of Im ? ?R( q x, ?; ?) and the suppression of Im ? ?R( q x, ?; ?) at low energies. This result indicates the importance of the dynamical effect by the spin fluctuation with q y= ? and small ?, which has a possibility to give rise to the attractive interaction for the electron pairing.
Universal behavior of quantum impurity scattering in a Tomonaga-Luttinger liquid
NASA Astrophysics Data System (ADS)
Liu, Yu-Liang
1999-03-01
Using bosonization and path-integral methods, we study general low-temperature behavior of nonmagnetic and magnetic impurity scattering in Tomonaga-Luttinger liquid, and calculate the electron Green function for a general backward scattering potential. We demonstrate that the electron density of state near the impurity site is suppressed by backward scattering, but it mainly remains invariant far away from the impurity, and that at zero temperature the electrons are completely reflected on the impurity site; the system breaks into two subsystems, but right- and left-moving electron fields have a twisted boundary condition. We also show that a testing charge can only be partially screened by conduction electrons, and in a strong interaction region the impurity susceptibility has a 1/T-type low-temperature behavior.
Anomalous Density of States of a Luttinger Liquid in Contact with a Superconductor
Winkelholz, C.; Fazio, R.; Hekking, F.W.; Schoen, G. [Institut fuer Theoretische Festkoerperphysik, Universtitaet Karlsruhe, 76128 Karlsruhe (Germany)] [Institut fuer Theoretische Festkoerperphysik, Universtitaet Karlsruhe, 76128 Karlsruhe (Germany); [Istituto di Fisica, Universita di Catania, viale A. Doria 6, 95129 Catania (Italy); [Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge CB3 0HE (United Kingdom); [Department of Technical Physics, Helsinki University of Technology, 02150 Espoo (Finland)
1996-10-01
We study the frequency and space dependence of the local tunneling density of states (DOS) of a Luttinger liquid (LL) connected to a superconductor. This coupling {ital strongly} modifies the single-particle properties of the LL. It significantly enhances the DOS near the Fermi level, whereas this quantity vanishes as a power law for an isolated LL. The enhancement is due to the interplay between electron-electron interactions and multiple backscattering processes of low-energy electrons at the interface between the LL and the superconductor. This anomalous behavior extends over large distances from the interface and may be detected by coupling normal probes to the system. {copyright} {ital 1996 The American Physical Society.}
Generalized Gibbs ensemble and work statistics of a quenched Luttinger liquid
NASA Astrophysics Data System (ADS)
Dóra, Balázs; Bácsi, Ádám; Zaránd, Gergely
2012-10-01
We analyze the probability distribution function (PDF) of work done on a Luttinger liquid for an arbitrary finite duration interaction quench and show that it can be described in terms of a generalized Gibbs ensemble. We construct the corresponding density matrix with explicit intermode correlations, and determine the duration and interaction dependence of the probability of an adiabatic transition and the PDF of nonadiabatic processes. In the thermodynamic limit, the PDF of work exhibits a non-Gaussian maximum around the excess heat, carrying almost all the spectral weight. In contrast, in the small system limit most spectral weight is carried by a delta peak at the energy of the adiabatic process, and an oscillating PDF with dips at energies commensurate to the quench duration and with an exponential envelope develops. Relevance to cold atom experiments is also discussed.
Transport and elementary excitations of a Luttinger liquid
Gianaurelio Cuniberti; Maura Sassetti; Bernhard Kramer
1996-01-01
The low-temperature AC conductance of a one-dimensional electron system with a strong interaction of finite range is calculated by using linear response theory. The conductance factorizes into parts which depend on the internal properties of the system, and the external probe. For short-range interaction, the result resembles that for non-interacting electrons, but with the zero-frequency limit and the Fermi velocity
NASA Astrophysics Data System (ADS)
Sano, Kazuhiro
2000-06-01
We investigate the Luttinger-liquid parameter K? of the Hubbard chain and the Hubbard ladder models by the Hartree-Fock approximation combined with the Luttinger-liquid relation. By calculating the charge susceptibility ?c and the Drude weight D in the Hartree-Fock approximation, we can obtain K? analytically. The form of K? for the Hubbard chain is similar to that from the result of bosonization method and consistent with the exact result in the weak coupling region. Comparing the value of K? for a finite system with the result of the numerical diagonalization method, we show that the result of K? for the Hubbard ladder is also reliable in the weak coupling region.
Critical spectral statistics as the Luttinger liquid of energy levels at a finite temperature
NASA Astrophysics Data System (ADS)
Kravtsov, V. E.
1999-11-01
We review the recent results on the energy level statistics in disordered conductors near the Anderson localization transition and other critical systems with multifractal eigenstates. We focus on the critical random matrix ensemble (CRMT) suggested by Mirlin and Fyodorov as a possible generic description of the critical parametric spectral statistics (CPSS). We show that in the region of large energy and/or parameter separations and weak multifractality this CRMT is equivalent to the Luttinger liquid of energy levels at a finite temperature with the interaction between the fictitious 1D fermions (energy levels) being dependent on the Dyson symmetry parameter = 1, 2, 4 and the temperature being proportional to the multifractality exponent = 1 - D2. We show that the CRMT is the simplest extension of the classical Wigner-Dyson random matrix ensemble for the case of finite dimensionless conductance g 1 and suggest the form of the two-level correlation functions for all the symmetry classes and all energy separations. We argue that these correlation functions coincide with the density correlation functions for the Calogero-Sutherland model at finite temperatures.
Shot noise and the Luttinger liquid-like properties of the FQHE
NASA Astrophysics Data System (ADS)
Glattli, D. C.; Rodriguez, V.; Perrin, H.; Roche, P.; Jin, Y.; Etienne, B.
2000-02-01
We present shot noise measurements in the Fractional Quantum Hall regime at ?= {1}/{3}. The two fractional edge channels which carry the current at the two opposite boundaries of a quantum Hall sample are weakly coupled by an artificial impurity, namely a Quantum Point Contact. This coupling gives rise to a current between the two edge channels and the random transfer of the charges gives rise to fluctuations of the current. For a weak coupling and for large voltages, recent experiments have established that the current noise power SI is proportional to the backscattered current IB and to the fractional charge e/3. For low voltages at low temperature, the chiral Luttinger liquid models suggest a renormalization of the coupling strength leading to strong backscattering even when the bare coupling is weak. These models predict a noise power proportional to the transmitted current I and to the electronic charge e. The new noise measurements presented here confirm the shot noise predictions at moderately low temperatures. However, at very low temperature, measurements show a surprising enhancement of the shot noise which is nearly doubled.
Universal duality in a Luttinger liquid coupled to a generic environment
NASA Astrophysics Data System (ADS)
Yurkevich, Igor V.; Yevtushenko, Oleg M.
2014-09-01
We study a Luttinger liquid (LL) coupled to a generic environment consisting of bosonic modes with arbitrary density-density and current-current interactions. The LL can be either in the conducting phase and perturbed by a weak scatterer or in the insulating phase and perturbed by a weak link. The environment modes can also be scattered by the imperfection in the system with arbitrary transmission and reflection amplitudes. We present a general method of calculating correlation functions under the presence of the environment and prove the duality of exponents describing the scaling of the weak scatterer and of the weak link. This duality holds true for a broad class of models and is sensitive to neither interaction nor environmental modes details, thus it shows up as the universal property. It ensures that the environment cannot generate new stable fixed points of the renormalization group flow. Thus, the LL always flows toward either conducting or insulating phase. Phases are separated by a sharp boundary which is shifted by the influence of the environment. Our results are relevant, for example, for low-energy transport in (i) an interacting quantum wire or a carbon nanotube where the electrons are coupled to the acoustic phonons scattered by the lattice defect; (ii) a mixture of interacting fermionic and bosonic cold atoms where the bosonic modes are scattered due to an abrupt local change of the interaction; (iii) mesoscopic electric circuits.
Edge states for topological insulators in two dimensions and their Luttinger-like liquids
Denis Bernard; Eun-Ah Kim; André LeClair
2012-09-25
Topological insulators in three spatial dimensions are known to possess a precise bulk/boundary correspondence, in that there is a one-to-one correspondence between the 5 classes characterized by bulk topological invariants and Dirac hamiltonians on the boundary with symmetry protected zero modes. This holographic characterization of topological insulators is studied in two dimensions. Dirac hamiltonians on the one dimensional edge are classified according to the discrete symmetries of time-reversal, particle-hole, and chirality, extending a previous classification in two dimensions. We find 17 inequivalent classes, of which 11 have protected zero modes. Although bulk topological invariants are thus far known for only 5 of these classes, we conjecture that the additional 6 describe edge states of new classes of topological insulators. The effects of interactions in two dimensions are also studied. We show that all interactions that preserve the symmetries are exactly marginal, i.e. preserve the gaplessness. This leads to a description of the distinct variations of Luttinger liquids that can be realized on the edge.
Fano resonance of LO-phonon-coupled excited states of Li acceptors in ZnSe and Luttinger parameters
NASA Astrophysics Data System (ADS)
Nakata, H.; Yamada, K.; Ohyama, T.
1999-11-01
Fano resonance between LO-phonon-coupled excited states of a Li acceptor and the valence-band state has been observed in bulk ZnSe through the infrared-absorption measurements. For the 2P5/2(?7) state of a Li acceptor, we found that the coupling strength of the Fano resonance f(h?0) is 2.8 cm-1, the distortion parameter q is 1.07, and the spectral width of the coupled state ? is 16.8 cm-1. It is concluded that a significant feature of the resonance peak is due to strong hole LO-phonon coupling in ZnSe. The Luttinger parameters ?1, ?2, and ?3 are estimated to be 6.44, 2.58, and 2.74, respectively.
NASA Astrophysics Data System (ADS)
Arrigoni, E.
2000-03-01
We study the problem of the crossover from one- to higher-dimensional metals by considering an array of Luttinger liquids (one-dimensional chains) coupled by a weak interchain hopping t?. We evaluate the exact asymptotic low-energy behavior of the self-energy in the anisotropic infinite-dimension limit. This limit extends the dynamical mean-field concept to the case of a chain embedded in a self-consistent medium. The system flows to a Fermi-liquid fixed point for energies below the dimensional crossover temperature, and the anomalous exponent ? renormalizes to zero, in the case of equal spin and charge velocities. In particular, the single-particle spectral function shows sharp quasiparticle peaks with nonvanishing weight along the whole Fermi surface, in contrast to the lowest-order result. Our result is obtained by carrying out a resummation of all diagrams of the expansion in t? contributing to the anisotropic D-->? limit. This is done by solving, in an almost completely analytic way, an asymptotically exact recursive equation for the renormalized vertices, within a skeleton expansion. Our outcome shows that perturbation expansions in t? restricted to lowest orders are unreliable below the crossover temperature. The extension to finite dimensions is discussed. This work extends our recent letter [Phys. Rev. Lett. 83, 128 (1999)], and includes all mathematical details.
Spectral functions in a magnetic field as a probe of spin-charge separation in a Luttinger liquid
Silvio Rabello; Qimiao Si
2003-02-07
We show that the single-particle spectral functions in a magnetic field can be used to probe spin-charge separation of a Luttinger liquid. Away from the Fermi momentum, the magnetic field splits both the spinon peak and holon peak; here the spin-charge separation nature is reflected in the different magnitude of the two splittings. At the Fermi momentum, the magnetic field splits the zero-field peak into {\\it four} peaks. The feasibility of experimentally studying this effect is discussed.
Spectral functions in a magnetic field as a probe of spin-charge separation in a Luttinger liquid
NASA Astrophysics Data System (ADS)
Rabello, Silvio; Si, Qimiao
2000-10-01
We show that the single-particle spectral functions in a magnetic field can be used to probe spin-charge separation of a Luttinger liquid. Away from the Fermi momentum, the magnetic field splits both the spinon peak and holon peak; here the spin-charge separation nature is reflected in the different magnitude of the two splittings. At the Fermi momentum, the magnetic field splits the zero-field peak into four. The feasibility of studying this effect using angle-resolved photoemission and momentum-resolved tunneling is discussed.
Charge-spin separation and the spectral properties of Luttinger liquids
Voit, J. (Institut-Laue-Langevin, Boite Postale 156, 38042 Grenoble (France))
1993-03-15
We compute the spectral function [rho]([ital q],[omega]) of the one-dimensional Luttinger model. Charge-spin separation gives spectral weight at frequencies between the charge and spin-fluctuation dispersions while spectral weight above [ital v][sub [rho
Luttinger-volume violating Fermi liquid in the pseudogap phase of the cuprate superconductors
Mei, Jiawei
Based on the NMR measurements on Bi[subscript 2]Sr[subscript 2?x]La[subscript x]CuO[subscript 6+?] (La-Bi2201) in strong magnetic fields, we identify the nonsuperconducting pseudogap phase in the cuprates as a Luttinger-volume ...
M. Dalmonte; W. Lechner; Zi Cai; M. Mattioli; A. M. Läuchli; G. Pupillo
2015-03-13
We investigate the quantum phases of hard-core bosonic atoms in an extended Hubbard model where particles interact via soft-shoulder potentials in one dimension. Using a combination of field-theoretical methods and strong-coupling perturbation theory, we demonstrate that the low-energy phase can be a conformal cluster Luttinger liquid (CLL) phase with central charge $c=1$, where the microscopic degrees of freedom correspond to mesoscopic ensembles of particles. Using numerical density-matrix-renormalization-group methods, we demonstrate that the CLL phase, first predicted in [Phys. Rev. Lett. 111, 165302 (2013)], is separated from a conventional Tomonaga-Luttinger liquid by an exotic critical point with central charge $c=3/2$. The latter is expression of an emergent conformal supersymmetry, which is not present in the original Hamiltonian. We discuss the observability of the CLL phase in realistic experimental settings with weakly-dressed Rydberg atoms confined to optical lattices. Using quantum Monte-Carlo simulations, we show that the typical features of CLLs are stable up to comparatively high temperatures. Using exact diagonalizations and quantum trajectory methods, we provide a protocol for adiabatic state preparation as well as quantitative estimates on the effects of particle losses.
Luttinger Liquid Physics and Spin-Flip Scattering on Helical Edges
M. Hohenadler; F. F. Assaad
2012-02-22
We investigate electronic correlation effects on edge states of quantum spin-Hall insulators within the Kane-Mele-Hubbard model by means of quantum Monte Carlo simulations. Given the U(1) spin symmetry and time-reversal invariance, the low-energy theory is the helical Tomanaga-Luttinger model, with forward scattering only. For weak to intermediate interactions, this model correctly describes equal-time spin and charge correlations, including their doping dependence. As apparent from the Drude weight, bulk states become relevant in the presence of electron-electron interactions, rendering the forward-scattering model incomplete. Strong correlations give rise to slowly decaying transverse spin fluctuations, and inelastic spin-flip scattering strongly modifies the single-particle spectrum, leading to graphene-like edge state signatures. The helical Tomanaga-Luttinger model is completely valid only asymptotically in the weak-coupling limit.
Charge-spin separation and the spectral properties of Luttinger liquids
Johannes Voit
1993-01-01
We compute the spectral function rho(q,omega) of the one-dimensional Luttinger model. Charge-spin separation gives spectral weight at frequencies between the charge and spin-fluctuation dispersions while spectral weight above vrhoq and below -vrhoq is related to the anomalous dimensions of the fermion operators. The generalization of these results to many-particle correlations is discussed as well as the possibilities for their experimental
NASA Astrophysics Data System (ADS)
Babichenko, V. S.
1999-10-01
An instability of the quasi-1D Luttinger liquid associated with the metal-insulator transition is considered. It is shown that the homogeneous metal ground state of this liquid is unstable and the charge density wave arises in the system. The wave vector of this charge density wave has nonzero component both along the direction of the chains and in the perpendicular direction. The ground state has a dielectric gap at the Fermi surface, the value of this gap being calculated.
NASA Astrophysics Data System (ADS)
Karnaukhov, I. N.
2000-12-01
One parameter family of the Lai-Sutherland models with hard-core repulsive potential is formulated and solved by the Bethe ansatz method in one dimension for an arbitrary core radius (? + 1)/2. The ground-state Bethe ansatz equations are analysed and solved numerically for an arbitrary electron density, several values of color components, and the core radius. The ground-state energy, the Fermi velocity, and the critical exponents describing the asymptotic behavior of the correlation functions at long distances have been calculated numerically for an arbitrary density of electrons. In contrast to the integrable models studied previously, the long-distance behavior is described by a strongly interacting Luttinger liquid state. This state is characterized by a large value of the critical exponent ? for the momentum distribution function (? > 1) and realized at a high electron density region n > nc(?(nc) = 1).
Guan, X. W.; Lee, J.-Y. [Department of Theoretical Physics, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia); Batchelor, M. T. [Department of Theoretical Physics, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia); Mathematical Sciences Institute, Australian National University, Canberra ACT 0200 (Australia); Yin, X.-G.; Chen Shu [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)
2010-08-15
A simple set of algebraic equations is derived for the exact low-temperature thermodynamics of one-dimensional multicomponent strongly attractive fermionic atoms with enlarged SU(N) spin symmetry and Zeeman splitting. Universal multicomponent Tomonaga-Luttinger liquid (TLL) phases are thus determined. For linear Zeeman splitting, the physics of the gapless phase at low temperatures belongs to the universality class of a two-component asymmetric TLL corresponding to spin-neutral N-atom composites and spin-(N-1)/2 single atoms. The equation of state which we obtained provides a precise description of multicomponent composite fermions and opens up the study of quantum criticality in one-dimensional systems of N-component Fermi gases with population imbalance.
Exact electronic Green functions in a Luttinger liquid with long-range interactions
NASA Astrophysics Data System (ADS)
Iucci, Aníbal; Naón, Carlos
2000-06-01
We compute the two-point (equal-time) electronic Green function in a Tomonaga-Luttinger system with long-range electron-electron interactions. We obtain an analytical expression for a ``super long-range'' potential of the form V(x)=e2d-?/\\|x\\|1-?. As a consistency check of our computational technique we also consider the particular case of a Coulomb potential. Our result confirms the exp-C(log x)3/2 long-distance behavior first obtained by Schulz.
Exact Friedel oscillations in the {ital g}=1/2 Luttinger liquid
Leclair, A. [Newman Laboratory, Cornell University, Ithaca, New York 14853 (United States)] [Newman Laboratory, Cornell University, Ithaca, New York 14853 (United States); Lesage, F.; Saleur, H. [Department of Physics, University of Southern California at Los Angeles, Los Angeles, California 90089-0484 (United States)] [Department of Physics, University of Southern California at Los Angeles, Los Angeles, California 90089-0484 (United States)
1996-11-01
A single impurity in the one-dimensional Luttinger model creates a local modification of the charge density analogous to the Friedel oscillations. In this paper, we present an exact solution of the case {ital g}=1/2 (the equivalent of the Toulouse point) at any temperature {ital T} and impurity coupling, expressing the charge density in terms of a hypergeometric function. We find in particular that at {ital T}=0 the oscillatory part of the density goes as ln{ital x} at small distance and {ital x}{sup {minus}1/2} at large distance. {copyright} {ital 1996 The American Physical Society.}
Exact electronic Green functions in a Luttinger liquid with long-range interactions
Aníbal Iucci; Carlos Naón
2000-03-28
We compute the 2-point (equal-time) electronic Green function in a Tomonaga-Luttinger system with long-range electron-electron interactions. We obtain an analytical expression for a "super long-range" potential of the form $V(x)=\\frac{e^2d^{-\\epsilon}}{|x|^{1-\\epsilon}}$. As a consistency check of our computational technique we also consider the particular case of a Coulomb potential. Our result confirms the $\\exp-C(logx)^{3/2}$ long-distance behavior first obtained by Schulz.
Magnetic properties of chains in cuprate superconductors studied by the Luttinger-liquid model
NASA Astrophysics Data System (ADS)
Zavidonov, A. Yu.; Brinkmann, D.
2000-02-01
Mapping the one-dimensional Hubbard model into the Luttinger-Tomonaga model, we have calculated the temperature dependencies of the chain copper nuclear magnetic spin-lattice relaxation rate and Knight shift for the normal state of the superconducting materials YBa2Cu3O7 and YBa2Cu4O8. The dynamic spin susceptibility has been obtained by using a bosonization technique and results of the renormalization group analysis for one-dimensional quantum systems. A comparison of our results with experiment shows that the model is able to reproduce the main features of the spin dynamics in both materials.
NASA Astrophysics Data System (ADS)
Mattis, Daniel C.
2012-09-01
This paper generalizes Luttinger's model by introducing curvature (d2?(k)/dk2?0) into the kinetic energy. An exact solution for arbitrary interactions is still possible in principle, but it now requires disentangling the eigenvalue spectrum of an harmonic string of interacting boson fields at each value of q. The additional boson fields, extracted from the excitation spectrum of the Fermi sea, are self-selected according to the nature and strength of the dispersion.
NASA Astrophysics Data System (ADS)
Mattis, Daniel C.
2014-10-01
This paper generalizes Luttinger's model by introducing curvature (d2?(k)/dk2 ? 0) into the kinetic energy. An exact solution for arbitrary interactions is still possible in principle, but it now requires disentangling the eigenvalue spectrum of an harmonic string of interacting boson fields at each value of q. The additional boson fields, extracted from the excitation spectrum of the Fermi sea, are self-selected according to the nature and strength of the dispersion.
Modified Luttinger model and quantum wires
NASA Astrophysics Data System (ADS)
Melgarejo, Augusto A.; Vericat, Fernando
2000-07-01
Luttinger model reproduces well the plasmons energy spectrum of quantum wires but it gives a momenta distribution where the Fermi surface has disappeared. However, photoluminescence experiments from real quantum wires cleary show a sharp Fermi surface. To reconcile both aspects, the accurate plasmons spectrum and the existence of the Fermi surface, within the same exact formalism, we propose adding to the Luttinger Hamiltonian in its original form, a parameterized term that accounts for the scattering of plasmons by the impurities existing in real (dirty) wires. The Hamiltonian we obtain is still diagonalizable by bosonization, so that the plasmons excitation spectrum and the momenta distribution are exactly obtained in terms of the scattering strength parameter. It is explicitly shown that the added term causes the restoration of the Fermi surface. Moreover, we calculate the density correlations and demonstrate that they decay quickly enough as to give a liquid behavior instead of the crystalline state characteristic of the original Luttinger model with long-range interaction. We also consider the current-carrying state. In particular we study how the system conductivity varies with the interactions range. The new Hamiltonian is applied to describe a quantum wire of width ? viewed as a strictly one dimensional system of electrons for which the confinement effects are considered through an effective (width-dependent) pair potential.
Self-heating of metallic carbon nanotube bundles in the regime of the Luttinger-liquid conductivity
NASA Astrophysics Data System (ADS)
Danilchenko, B. A.; Tripachko, N. A.; Voytsihovska, E. A.; Obukhov, I. A.; Yaskovets, I. I.; Sundqvist, B.
2011-08-01
The conductivity of bundles of carbon single-walled nanotubes with metallic conductivity (metallic nanotubes) is investigated over the wide temperature range 4.2-330 K and electrical fields up to 50 V. The usage of short electrical pulses of the duration of 10 ns allowed to avoid an influence of a self-heating of the investigated structures on current-voltage characteristics. It is shown that the temperature dependence of conductivity is described by the power function G?T?. At helium temperatures the asymptotic dependence of current on applied voltage is close to J?V1+? with ? = 0.45. From comparison of the obtained results of measurements with calculations, it is shown that the conductivity of nanotube bundles is well described within the theory of the Luttinger-liquid conductivity for one-dimensional conductors. The self-heating of the carbon nanotube bundles was observed in the case of measurements in the regime of dc current. A method for determination of the self-heating temperature of nanotube bundles as a function of an applied electrical field is proposed. The power dependence of the self-heating temperature on voltage T?Vp with the exponent p = 2.1 was observed above some threshold voltage in the temperature range 4.2-200 K. Above 200 K the exponent decreased down to p = 1.35.
Luttinger-liquid features in the resonant Raman spectra of quantum wires
NASA Astrophysics Data System (ADS)
Sassetti, M.; Kramer, B.
1998-11-01
Using the bosonization technique, we develop a theory for the Raman scattering of the interacting electrons in quantum wires. The energy spectra of the collective excitations in a two-subband model are given. The density correlation functions for the Raman cross section are calculated. The charge and spin density excitations observed in recent Raman experiments are identified. Hitherto unexplained single particle excitations which appear near resonance and are independent of the relative polarization of incoming and scattered light are shown to originate in higher order spin density excitations, which can be evaluated due to the bosonization. For the intraband excitations, the peak strengths in the Raman cross section as a function of the frequency of the incoming light is explicitely calculated. Power law behaviors depending on the strength of the interaction are predicted.
NASA Astrophysics Data System (ADS)
Del Maestro, Adrian; Affleck, Ian
2010-08-01
Harmonically trapped ultracold atoms and H4e in nanopores provide different experimental realizations of bosons in one dimension, motivating the search for a more complete theoretical understanding of their low-energy properties. Worm algorithm path-integral quantum Monte Carlo results for interacting bosons restricted to the one dimensional continuum are compared to the finite temperature and system size predictions of Luttinger-liquid theory. For large system sizes at low temperature, excellent agreement is obtained after including the leading irrelevant interactions in the Hamiltonian which are determined explicitly.
Renormalization Group and Asymptotic Spin--Charge separation for Chiral Luttinger liquids
P. Falco; V. Mastropietro
2007-07-19
The phenomenon of Spin-Charge separation in non-Fermi liquids is well understood only in certain solvable d=1 fermionic systems. In this paper we furnish the first example of asymptotic Spin-Charge separation in a d=1 non solvable model. This goal is achieved using Renormalization Group approach combined with Ward-Identities and Schwinger-Dyson equations, corrected by the presence of a bandwidth cut-offs. Such methods, contrary to bosonization, could be in principle applied also to lattice or higher dimensional systems.
Magnetic impurity in a Luttinger liquid: A view from conformal field theory
Froejdh, P. [Univ. of Washington, Seattle, WA (United States); Johannesson, H. [Univ. of Technology and Goeteborg (Sweden)
1995-05-01
Exact results are reported for the low-temperature thermodynamics of a spin-1/2 magnetic impurity coupled to a 1D interacting electron system. The use of conformal field theory techniques reveals that there are only two types of critical behaviors consistent with the symmetrics of the problem: either a local Fermi liquid, or else a theory identical to that recently proposed by Furusaki and Nagaosa. We also show that forward electron scattering on the impurity produces the same critical behavior as the two-channel Kondo effect for noninteracting electrons.
Kane, Charles
) interacting electron gas, employing the Luttinger liquid model. Both thermal conductance and thermopower The Wiedemann-Franz law, which relates the thermal and electrical conductivity k, s of metals, played a cen are analyzed for a pure 1D gas and with impurities. The universal ratio of electrical to thermal conductance
ARPES spectra lineshape analysis in quasi-1 dimensional K_0.3MoO_3: the CDW vs. the Luttinger liquid
NASA Astrophysics Data System (ADS)
Gweon, G.-H.; Denlinger, J. D.; Allen, J. W.; Claessen, R.; Olson, C. G.; Schneemeyer, L. F.
2000-03-01
We report a detailed lineshape analysis of the depletion of EF weight in angle resolved photoemission spectroscopy (ARPES) spectra for the quasi-1 dimensional ``blue bronze'' K_0.3MoO_3, in the metallic state above its CDW transition (T=180K). We examine the applicability of lineshape theories based on two physically quite different non-Fermi liquid (NFL) scenarios, the fluctuating CDW and the Luttinger liquid (LL). The former is generally accepted as the essential ingredient for the blue bronze metallic phase, and the latter presently has more the status of a speculation. We find that the LL lineshape provides the better description of the data, but that both have deficiencies. We take this result to imply the need in the blue bronze metallic phase for a model combining LL and CDW physics, for example the Luther-Emery model, for which present lineshape theory is not yet developed as fully as for the CDW or the LL.
Andreas Vogler; Ralf Labouvie; Giovanni Barontini; Sebastian Eggert; Vera Guarrera; Herwig Ott
2014-10-07
We study the thermodynamic properties of a 2D array of coupled one-dimensional Bose gases. The system is realized with ultracold bosonic atoms loaded in the potential tubes of a two-dimensional optical lattice. For negligible coupling strength, each tube is an independent weakly interacting 1D Bose gas featuring Tomonaga Luttinger liquid behavior. By decreasing the lattice depth, we increase the coupling strength between the 1D gases and allow for the phase transition into a 3D condensate. We extract the phase diagram for such a system and compare our results with theoretical predictions. Due to the high effective mass across the periodic potential and the increased 1D interaction strength, the phase transition is shifted to large positive values of the chemical potential. Our results are prototypical to a variety of low-dimensional systems, where the coupling between the subsystems is realized in a higher spatial dimension such as coupled spin chains in magnetic insulators.
Ion-beam excitation of liquid argon
NASA Astrophysics Data System (ADS)
Hofmann, M.; Dandl, T.; Heindl, T.; Neumeier, A.; Oberauer, L.; Potzel, W.; Roth, S.; Schönert, S.; Wieser, J.; Ulrich, A.
2013-10-01
The scintillation light of liquid argon has been recorded wavelength and time resolved with very good statistics in a wavelength interval ranging from 118 nm through 970 nm. Three different ion beams, protons, sulfur ions and gold ions, were used to excite liquid argon. Only minor differences were observed in the wavelength-spectra obtained with the different incident particles. Light emission in the wavelength range of the third excimer continuum was found to be strongly suppressed in the liquid phase. In time-resolved measurements, the time structure of the scintillation light can be directly attributed to wavelength in our studies, as no wavelength shifter has been used. These measurements confirm that the singlet-to-triplet intensity ratio in the second excimer continuum range is a useful parameter for particle discrimination, which can also be employed in wavelength-integrated measurements as long as the sensitivity of the detector system does not rise steeply for wavelengths longer than 190 nm. Using our values for the singlet-to-triplet ratio down to low energies deposited a discrimination threshold between incident protons and sulfur ions as low as ˜2.5 keV seems possible, which represents the principle limit for the discrimination of these two species in liquid argon.
Elles, Christopher G.; Shkrob, Ilya A.; Crowell, Robert A.; Bradforth, Stephen E.
2007-04-25
The authors use transient absorption spectroscopy to monitor the ionization and dissociation products following two-photon excitation of pure liquid water. The primary decay mechanism changes from dissociation at an excitation energy of 8.3e...
Ionization and Excitation in Non-Polar Organic Liquids.
ERIC Educational Resources Information Center
Lipsky, Sanford
1981-01-01
Reviews recent advances in radiation chemistry concerning the effect of high-energy radiation on organic liquids. Discusses the general nature of excited and ionized states, pathways for decay, the effect of environmental perturbation, the behavior of an electron in a nonpolar liquid, and comparison of photochemical and radiation chemical effects.…
Kohn-Luttinger effect and the instability of a two-dimensional repulsive Fermi liquid at [ital T]=0
Chubukov, A.V. (Department of Physics and Center for Superconductivity, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois 61801 (United States) P. L. Kapitza Institute for Physical Problems, 117973, ul. Kosygina 2, Moscow (Russian Federation))
1993-07-01
We consider the possibility for a pairing in a two-dimensional (2D) repulsive Fermi liquid due to the singularity in the scattering amplitude [Gamma]([ital q]) at the momentum transfer [ital q][le]2[ital p][sub [ital F
Johannes Voit; Theoretische Physik
1995-01-01
I attempt to give a pedagogical overview of the progress which has occurred during the past decade in the description of one-dimensional correlated fermions. Fermi liquid theory based on a quasi-particle picture, breaks down in one dimension because of the Peierls divergence and because of charge-spin separation. It is replaced by a Luttinger liquid whose elementary excitations are collective charge
Transverse excitations in liquid Fe, Cu and Zn.
Hosokawa, S; Inui, M; Kajihara, Y; Tsutsui, S; Baron, A Q R
2015-05-20
Transverse acoustic (TA) excitation modes were observed in inelastic x-ray scattering spectra of liquid Fe, Cu and Zn. From the analysis of current correlation functions, we concluded that TA excitation modes can experimentally be detected through the quasi-TA branches in the longitudinal current correlation spectra in these liquid metals. The microscopic elastic constants are estimated and a characteristic difference from macroscopic polycrystalline value was found in Poisson's ratio of liquid Fe, which shows an extremely softer value of ?0.38 compared with the macroscopic value of ?0.275. The lifetime of the TA modes were determined to be ?0.45 ps for liquid Fe and Cu and ?0.55 ps for liquid Zn, reflecting different interatomic correlations between liquid transition metals and non-transition metals. The propagation length of the TA modes are ?0.85 nm in all of liquid metals, corresponding to the size of icosahedral or similar size of cages formed instantaneously in these liquid metals. PMID:25923651
Anomalous BCS Equation for a Luttinger Superconductor
NASA Astrophysics Data System (ADS)
Mastropietro, V.
A self-consistence equation describing a superconductor whose normal state is a Luttinger liquid is computed in a rigorous way by renormalization group techniques. The gap and the critical temperatures are quite different with respect to the ones of normal superconductors (i.e. superconductors whose normal state is a Fermi liquid) and in particular, the critical temperature can be quite high for suitable values of the parameters. Such self-consistence equation can be obtained in a BCS mean field theory for a model of two Mattis models exchanging Cooper pairs. The connection of this model with recent theories of high Tc superconductivity is briefly discussed.
NASA Astrophysics Data System (ADS)
Takenaka, K.; Nakada, K.; Osuka, A.; Horii, S.; Ikuta, H.; Hirabayashi, I.; Sugai, S.; Mizutani, U.
2000-12-01
The optical spectra of PrBa2Cu4O8 show large in-plane anisotropy. For the a polarization ( E ? chain), the spectrum is characterized by a gap of 1.4 eV, indicating the charge-transfer insulating nature of the CuO2 planes. For the metallic chain direction ( E?b), the spectrum deviates from a simple Drude response; reflectivity Rb\\(?\\) shows a sharp edge at ~1 eV but it also shows a dip at ~15 meV, which splits the conductivity spectrum into two parts-a zero-energy mode with small weight and a pronounced 40 meV mode. These features are discussed in terms of a Tomonaga-Luttinger liquid in a doped 1D Mott insulator and compared with 1D Bechgaard salts.
Takenaka, K; Nakada, K; Osuka, A; Horii, S; Ikuta, H; Hirabayashi, I; Sugai, S; Mizutani, U
2000-12-18
The optical spectra of PrBa2Cu4O8 show large in-plane anisotropy. For the a polarization (E perpendicular chain), the spectrum is characterized by a gap of 1.4 eV, indicating the charge-transfer insulating nature of the CuO2 planes. For the metallic chain direction (E // b), the spectrum deviates from a simple Drude response; reflectivity R(b)(omega) shows a sharp edge at approximately 1 eV but it also shows a dip at approximately 15 meV, which splits the conductivity spectrum into two parts--a zero-energy mode with small weight and a pronounced 40 meV mode. These features are discussed in terms of a Tomonaga-Luttinger liquid in a doped 1D Mott insulator and compared with 1D Bechgaard salts. PMID:11136013
Contactless magnetic excitation of acoustic cavitation in liquid metals
NASA Astrophysics Data System (ADS)
Grants, Ilm?rs; Gerbeth, Gunter; Bojarevi?s, Andris
2015-05-01
A steady axial magnetic field is applied to a liquid metal zone heated by induction currents. The resulting alternating Lorentz force causes pressure oscillations that being strong enough lead to cavitation in the molten metal. Amplitude of the pressure oscillations is proportional to the product of the induced currents and the steady axial magnetic field induction. We follow an approach where the acoustic pressure is maximized by the induction currents. The onset of cavitation is identified by the occurrence of sub-harmonics of the drive frequency in sound recorded at the surface of the experimental cell. It is demonstrated that cavitation in a liquid metal may be excited by a superimposed axial magnetic field of a moderate 0.5 T induction.
Dissociative ionization of liquid water induced by vibrational overtone excitation
Natzle, W.C.
1983-03-01
Photochemistry of vibrationally activated ground electronic state liquid water to produce H/sup +/ and OH/sup -/ ions has been initiated by pulsed, single-photon excitation of overtone and combination transitions. Transient conductivity measurements were used to determine quantum yields as a function of photon energy, isotopic composition, and temperature. The equilibrium relaxation rate following perturbation by the vibrationally activated reaction was also measured as a function of temperature reaction and isotopic composition. In H/sub 2/O, the quantum yield at 283 +- 1 K varies from 2 x 10/sup -9/ to 4 x 10/sup -5/ for wave numbers between 7605 and 18140 cm/sup -1/. In D/sub 2/O, the dependence of quantum yield on wavelength has the same qualitative shape as for H/sub 2/O, but is shifted to lower quantum yields. The position of a minimum in the quantum yield versus hydrogen mole fraction curve is consistent with a lower quantum yield for excitation of HOD in D/sub 2/O than for excitation of D/sub 2/O. The ionic recombination distance of 5.8 +- 0.5 A is constant within experimental error with temperature in H/sub 2/O and with isotopic composition at 25 +- 1/sup 0/C.
Montfrooij, Wouter
Polarized neutron scattering investigation of excitations at low momentum transfer in liquid Ga: Liquid metals; Scattering; Excitations; Sum-rule violation New polarized neutron scattering experiments in the literature. Our polarized neutron scattering experiments show that this increased cross-section cannot
Tunneling spectroscopy calculations of a Luttinger wire
NASA Astrophysics Data System (ADS)
Governale, Michele; Grifoni, Milena; Schön, Gerd
2000-12-01
We investigate the tunneling current between a one-dimensional (1D) wave guide and a metallic electrode. To be specific, we consider as an electrode a two-dimensional electron gas (2DEG) coupled to the 1D system over a finite length L by a thin tunnel barrier. Treating the 1D electrons within the Luttinger liquid model, we evaluate the tunneling current which flows through the barrier. Tunneling is assumed to be local (rather than being described by a constant matrix element in reciprocal space) and the spatial extent of the contact is taken into account. A characteristic maximum of the current for optimal barrier lengths is found. We calculate the finite-temperature spectral density of the 1D correlated electrons, which is needed to evaluate the current in the peak region.
Renormalization Group and Asymptotic SpinCharge separation for Chiral Luttinger
Roma "La Sapienza", Università di
Renormalization Group and Asymptotic SpinCharge separation for Chiral Luttinger liquids. P. Falco Scientifica, I-00133, Roma Abstract The phenomenon of Spin-Charge separation in non-Fermi liquids is well of asymptotic Spin-Charge separation in a d = 1 non solvable model. This goal is achieved using Renormalization
Topological Approach to Luttinger's Theorem and the Fermi Surface of a Kondo Lattice
Masaki Oshikawa
2000-01-01
A nonperturbative proof of Luttinger's theorem, based on a topological argument, is given for Fermi liquids in arbitrary dimensions. Application to the Kondo lattice shows that even completely localized spins contribute to the Fermi sea volume as electrons, whenever the system can be described as a Fermi liquid.
Topological Approach to Luttinger's Theorem and the Fermi Surface of a Kondo Lattice
NASA Astrophysics Data System (ADS)
Oshikawa, Masaki
2000-04-01
A nonperturbative proof of Luttinger's theorem, based on a topological argument, is given for Fermi liquids in arbitrary dimensions. Application to the Kondo lattice shows that even completely localized spins contribute to the Fermi sea volume as electrons, whenever the system can be described as a Fermi liquid.
A numerical study of liquid sloshing in a two-dimensional tank under external excitations
NASA Astrophysics Data System (ADS)
Hou, Ling; Li, Fangcheng; Wu, Chunliang
2012-09-01
In this research, liquid sloshing behavior in a 2-D rectangular tank was simulated using ANSYS-FLUENT software subject to single or multiple-coupled external excitations (such as sway coupled with roll, and sway and roll coupled with heave). The volume of fluid (VOF) method was used to track the free surface of sloshing. External excitation was imposed through the motion of the tank by using the dynamic mesh technique. The study shows that if the tank is subjected to multiple coupled excitations and resonant excitation frequencies, liquid sloshing will become violent and sloshing loads, including impact on the top wall, will be intensified.
Adhikari, Aniruddha; Sahu, Kalyanasis; Dey, Shantanu; Ghosh, Subhadip; Mandal, Ujjwal; Bhattacharyya, Kankan
2007-11-01
Solvation dynamics in a neat ionic liquid, 1-pentyl-3-methyl-imidazolium tetra-flouroborate ([pmim][BF4]) and its microemulsion in Triton X-100 (TX-100)/benzene is studied using femtosecond up-conversion. In both the neat ionic liquid and the microemulsion, the solvation dynamics is found to depend on excitation wavelength (lambda(ex)). The lambda(ex) dependence is attributed to structural heterogeneity in neat ionic liquid (IL) and in IL microemulsion. In neat IL, the heterogeneity arises from clustering of the pentyl groups which are surrounded by a network of cation and anions. Such a nanostructural organization is predicted in many recent simulations and observed recently in an X-ray diffraction study. In an IL microemulsion, the surfactant (TX-100) molecules aggregate in form of a nonpolar peripheral shell around the polar pool of IL. The micro-environment in such an assembly varies drastically over a short distance. The dynamic solvent shift (and average solvation time) in neat IL as well as in IL microemulsions decreases markedly as lambda(ex) increases from 375 to 435 nm. In a [pmim][BF4]/water/TX-100/benzene quaternary microemulsion, the solvation dynamics is slower than that in a microemulsion without water. This is ascribed to the smaller size of the water containing microemulsion. The anisotropy decay in an IL microemulsion is found to be faster than that in neat IL. PMID:17944511
Slosh wave excitation due to cryogenic liquid reorientation in space-based propulsion system
NASA Technical Reports Server (NTRS)
Hung, R. J.; Shyu, K. L.; Lee, C. C.
1991-01-01
The objective of the cryogenic fluid management of the spacecraft propulsion system is to develop the technology necessary for acquistion or positioning of liquid and vapor within a tank in reduced gravity to enable liquid outflow or vapor venting. In this study slosh wave excitation induced by the resettling flow field activated by 1.0 Hz medium frequency impulsive reverse gravity acceleration during the course of liquid fluid reorientation with the initiation of geyser for liquid filled levels of 30, 50, and 80 percent have been studied. Characteristics of slosh waves with various frequencies excited are discussed.
NASA Astrophysics Data System (ADS)
Dobryakov, A. L.; Kovalenko, S. A.; Farztdinov, V. M.; Merkulova, S. P.; Ernsting, N. P.; Lozovik, Yu. E.
2000-10-01
A method for probing Fermi liquid (FL) versus non-Fermi liquid (NFL) behavior in the normal state of high Tc oxide-superconductors YBa 2Cu 3O 7- ? by femtosecond pump-supercontinuum probe spectroscopy is presented. The method is based on the determination of the spectral dependence of non-equilibrium charge carriers relaxation rate ?( ?probe) in a wide spectral range of probing, ?? probe=1.6-3.2 eV. It is shown that the relaxation rate decreases sharply for the optical transitions in the vicinity of the Fermi level EF, the position of the rate minimum pointing to the location of EF. The probe energy dependence of the relaxation rate around the minimum gives unique information on the damping rate of quasi-particles near the Fermi level and hence can resolve the FL versus NFL behavior. Deviations from the FL behavior in YBa 2Cu 3O 7- ? are observed and discussed.
Liquid hydrogen slosh waves excited by constant reverse gravity acceleration of geyser initiation
NASA Technical Reports Server (NTRS)
Hung, R. J.; Shyu, K. L.; Lee, C. C.
1992-01-01
The requirement to settle or to position liquid fuel over the outlet end of the spacecraft propellant tank before main engine restart poses a microgravity fluid behavior problem. Resettlement or reorientation of liquid propellant can be accomplished by providing the optimal acceleration to the spacecraft such that the propellant is reoriented over the tank outlet. In this study slosh wave excitation induced by the resettling flowfield during the course of liquid reorientation with the initiation of geyser for liquid-filled levels of 30, 50, 65, 70, and 80 percent have been studied. Characteristics of slosh waves with various frequencies excited are discussed. Slosh wave excitations will affect the fluid stress distribution exerted on the container wall and shift the fluid mass distribution inside the container, which imposes the time-dependent variations in the moment of inertia of the container. This information is important for the spacecraft control during the course of liquid reorientation.
Excited state proton transfer in ionic liquid mixed micelles.
Mondal, Tridib; Das, Atanu Kumar; Sasmal, Dibyendu Kumar; Bhattacharyya, Kankan
2010-10-21
Excited state proton transfer (ESPT) of pyranine (8-hydroxypyranine-1,3,6-trisulfonate, HPTS) in room temperature ionic liquid (RTIL) mixed micelles is studied by femtosecond up-conversion. The mixed micelle consists of a triblock copolymer, (PEO)(20)-(PPO)(70)-(PEO)(20) (Pluronic P123), and one of the two RTILs, 1-pentyl-3-methyl-imidazolium bromide ([pmim][Br]) and 1-pentyl-3-methyl-imidazolium tetra-fluoroborate ([pmim][BF(4)]). The size and structure of the mixed micelle vary with the relative amount of the RTIL. For [pmim][Br], the hydrodynamic diameter of the mixed micelle is 26 nm in 0.3 M RTIL and 3500 nm in 3.0 M RTIL. The time constant of initial proton transfer (?(PT)) in P123 micelle (65 ps) is 10 times slower than that (5 ps) in water, while the time constants of recombination (?(rec)) and dissociation (?(diss)) are 2-3 times slower in P123 micelle. On addition of the RTIL, the rate of ESPT is markedly modified. In 0.3 M RTIL-P123 mixed micelle, ?(PT) is shorter than that in P123 micelle. In the mixed micelle, ?(PT) increases with an increase in the concentration of the RTIL (230 ps in 3 M [pmim][Br] and 55 ps in 0.9 M [pmim][BF(4)]). This is attributed to large scale penetration of the P123 micelle by RTIL replacing water molecules. The time constants of proton transfer (?(PT), ?(rec), and ?(diss)) are faster than the slowest component (200-500 ps) of solvation dynamics. It seems that the ultrafast component of solvation (<0.3 ps and <5 ps) is enough for inducing proton transfer. The time constant of the proton transfer (?(PT)) in [pmim][BF(4)]-P123 mixed micelle is longer (?20%) than that in [pmim][Br]-P123 mixed micelle for the same concentration of RTIL. The counterion dependence of ESPT is attributed to the difference in the structure and greater hydrophobicity of the [pmim][BF(4)]. PMID:20863113
Tomonaga-Luttinger features in the resonant Raman spectra of quantum wires
NASA Astrophysics Data System (ADS)
Kramer, B.; Sassetti, M.
2000-08-01
The differential cross section for resonant Raman scattering from the collective modes in a one-dimensional system of interacting electrons is calculated nonperturbatively using the bosonization method. The results indicate that resonant Raman spectroscopy is a powerful tool for studying Tomonaga-Luttinger liquid behavior in quasi-one-dimensional electron systems.
Excited level anisotropy produced by ion-solid and ion-liquid surface interactions
Lee, Chin Shuang
1977-01-01
model still does not exist which can predict the preferred populations in each sublevel of the excited atom after the foil excitation. In this experiment, the measurement of the anisotropic excitation of boron ion levels by solids and a liquid..., the Joule heating melts the solid gallium into liquid gallium 0 The melting temperature is 29 78 C Before the polarization of light from tHe boron ion beam was measured, a thermocouple was used to cal- ibrate the temperature as a function of heating...
Parametrically excited sectorial oscillation of liquid drops floating in ultrasound.
Shen, C L; Xie, W J; Wei, B
2010-04-01
We report experiments in which the nonaxisymmetric sectorial oscillations of water drops have been excited using acoustic levitation and an active modulation method. The observed stable sectorial oscillations are up to the seventh mode. These oscillations are excited by parametric resonance. The oblate initial shape of the water drops is essential to this kind of excitations. The oscillation frequency increases with mode number but decreases with equatorial radius for each mode number. The data can be well described by a modified Rayleigh equation, without the use of additional parameters. PMID:20481825
Experimental study on chaos of a liquid-filled tank under vertical excitation
Okazaki, K.; Watanabe, K. [Yamagata Univ., Yonezawa (Japan). Dept. of Mechanical System Engineering; Tani, J. [Tohoku Univ., Sendai (Japan). Inst. of Fluid Science
1995-11-01
This paper is concerned with an experimental study on the chaos of a partially liquid-filled cylindrical tank under vertical excitation. The test cylinder made of polyester film was harmonically excited with constant displacement amplitude. It has been well known that the partially liquid-filled cylindrical tank under periodic vertical excitation gives rise to the parametoric resonance. As the excitation amplitude increases, the nonlinear response characteristics of soft and hard spring types as well as chaos were found to appear in this system. The occurrence of chaos was recognized by the time history, Poincare map, phase trajectory, and power spectrum. Furthermore, the sloshing and chaotic motion of the liquid surface were found to appear in the lower frequency range than the parametric resonance and chaotic motion of the cylindrical shell wall.
Magnetic-field dependence of coupled Luttinger chains
Schmeltzer, D. [Department of Physics, City College of the City University of New York, New York, New York 10031 (United States)] [Department of Physics, City College of the City University of New York, New York, New York 10031 (United States); Bishop, A.R. [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)
1998-03-01
The model of two coupled Luttinger chains in the presence of a magnetic field is investigated for weak and strong magnetic field strengths. For magnetic fields that are close to the commensurate wave vector condition Q{approx}2 K{sub F} (with K{sub F} the Fermi wave vector), incoherent tunneling between the chains takes place. Under these conditions, we propose that the incoherent non-Fermi-liquid Anderson fixed point is realized. Implications for the normal-state behavior of organic and cuprate superconductors are discussed. {copyright} {ital 1998} {ital The American Physical Society}
Sloshing response of nonuniform density liquid in a laterally excited tank
Tang, Y. [Argonne National Lab., IL (United States). Reactor Engineering Division
1995-01-01
A study on the sloshing response of nonuniform density liquid in a tank undergoing lateral base excitations is presented. The system considered is a circular cylindrical tank containing a liquid whose density increases with the liquid depth. The density distribution along the depth can be of any arbitrary continuous function. In the analysis, the liquid field is divided into n layers. The thicknesses of the liquid layers can be different, but the density of each liquid layer is considered to be uniform and its value is assigned to be the value of the original liquid density at the mid-height of that layer. The problem is solved by the transfer matrix technique. The effect of the nonuniform liquid density on the sloshing response is illustrated in a numerical example in which the linear and cosine distributions of the liquid density are assumed. The response functions examined include the sloshing frequencies, surface wave height, and the associated convective hydrodynamic pressure. The results are presented in tabular and graphical forms. It is found that the natural frequencies of the sloshing motion for nonuniform density liquid are lower than those of the uniform density liquid of the same total depth contained in an identical tank. Also, it is shown that for nonuniform density liquid, the maximum sloshing wave height may increase significantly and the magnitude of the convective hydrodynamic pressure may be quite different compared with that of a uniform liquid contained in an identical tank.
Kohn-Luttinger effect in gauge theories
Schaefer, T. [Department of Physics, North Carolina State University, Raleigh, North Carolina 27695 (United States)
2006-09-01
Kohn and Luttinger showed that a many body system of fermions interacting via short range forces becomes superfluid even if the interaction is repulsive in all partial waves. In gauge theories such as QCD the interaction between fermions is long range and the assumptions of Kohn and Luttinger are not satisfied. We show that in a U(1) gauge theory the Kohn-Luttinger phenomenon does not take place. In QCD attractive channels always exist, but there are cases in which the primary pairing channel leaves some fermions ungapped. As an example we consider the unpaired fermion in the 2SC phase of QCD with two flavors. We show that it acquires a very small gap via a mechanism analogous to the Kohn-Luttinger effect. The gap is too small to be phenomenologically relevant.
H. Grosse; E. Langmann; E. Raschhofer
1996-09-27
We study the Luttinger-Schwinger model, i.e. the (1+1) dimensional model of massless Dirac fermions with a non-local 4-point interaction coupled to a U(1)-gauge field. The complete solution of the model is found using the boson-fermion correspondence, and the formalism for calculating all gauge invariant Green functions is provided. We discuss the role of anomalies and show how the existence of large gauge transformations implies a fermion condensate in all physical states. The meaning of regularization and renormalization in our well-defined Hilbert space setting is discussed. We illustrate the latter by performing the limit to the Thirring-Schwinger model where the interaction becomes local.
Introduction 1+1 dimensions: Luttinger Liquids
theories where the coupling constant flows (either in the IR or in the UV) to a fixed point where use perturbation theory to probe phenomena in the vicinity of the fixed point. B. Sathiapalan BTZ use perturbation theory to probe phenomena in the vicinity of the fixed point. B. Sathiapalan BTZ
Generalization of the Luttinger theorem for fermionic ladder systems
NASA Astrophysics Data System (ADS)
Gagliardini, Patrick; Haas, Stephan; Rice, T. M.
1998-10-01
We apply a generalized version of the Lieb-Schultz-Mattis theorem to fermionic ladder systems to show the existence of a low-lying excited state (except for some special fillings). This can be regarded as a nonperturbative proof for the conservation under interaction of the sum of the Fermi wave vectors of the individual channels, corresponding to a generalized version of the Luttinger theorem to fermionic ladder systems. We conclude by noticing that the Lieb-Schultz-Mattis theorem is not applicable in this form to show the existence of low-lying excitations in the limit that the number of legs goes to infinity, e.g., in the limit of a 2D plane.
One-dimensional Hubbard–Luttinger model for carbon nanotubes
NASA Astrophysics Data System (ADS)
Ishkhanyan, H. A.; Krainov, V. P.
2015-06-01
A Hubbard–Luttinger model is developed for qualitative description of one-dimensional motion of interacting Pi-conductivity-electrons in carbon single-wall nanotubes at low temperatures. The low-lying excitations in one-dimensional electron gas are described in terms of interacting bosons. The Bogolyubov transformation allows one to describe the system as an ensemble of non-interacting quasi-bosons. Operators of Fermi excitations and Green functions of fermions are introduced. The electric current is derived as a function of potential difference on the contact between a nanotube and a normal metal. Deviations from Ohm law produced by electron–electron short-range repulsion as well as by the transverse quantization in single-wall nanotubes are discussed. The results are compared with experimental data.
Electromechanical response to white noise excitation in a ferroelectric liquid crystal
Boyer, Edmond
(EM) coupling in a chiral liquid crystal was first investigated under a white electrical excitation, magnetic response [5]. We suggest to apply this method to study electric and mechanical properties du type bruit blanc. La réponse mécanique du système a été détectée dans le domaine de fréquence 0
Heterogeneous thermal excitation and relaxation in supercooled liquids.
Weinstein, Susan; Richert, Ranko
2005-12-01
We investigate a phenomenological model which rationalizes the effects of dielectric hole burning on the basis of heterogeneous dielectric and specific heat relaxation in supercooled liquids. The quantitative agreement between model predictions and dielectric hole-burning observations is lost if the assumption of correlated dielectric and thermal relaxation times is removed from the model. This suggests that dynamically distinct domains in real liquids are associated with a time constant which characterizes both the structural and thermal relaxation behaviors. The calculations demonstrate that the observed burn-induced modifications reflect the spectral selectivity and persistence time of the fictive temperatures within these domains, and that 100 or more cycles of the sinusoidal burn field can be required to saturate the heat accumulated in the slow degrees of freedom. It is also shown that the recovery of dielectric holes is entirely accounted for by the model, and that the persistence times do not provide direct insight into rate exchange processes. Additionally, the model predicts that the heating effects considered here are a significant source of nonlinear dielectric behavior, even in the absence of deliberate frequency selective hole burning. PMID:16375488
Laser excitation of Ba+ ions in liquid helium M. Himbert, A. Lezama (*) and J. Dupont-Roc
Paris-Sud XI, Université de
Curie (Paris VI). Similar properties are also true for metastable 2 3SI helium atoms or alkali2009 Laser excitation of Ba+ ions in liquid helium M. Himbert, A. Lezama (*) and J. Dupont been injected in liquid helium at 0.5 K. Laser excitation of their resonance 6s-6p transition at 455 nm
Highly mobile gapless excitations in a two-dimensional candidate quantum spin liquid.
Yamashita, Minoru; Nakata, Norihito; Senshu, Yoshinori; Nagata, Masaki; Yamamoto, Hiroshi M; Kato, Reizo; Shibauchi, Takasada; Matsuda, Yuji
2010-06-01
The nature of quantum spin liquids, a novel state of matter where strong quantum fluctuations destroy the long-range magnetic order even at zero temperature, is a long-standing issue in physics. We measured the low-temperature thermal conductivity of the recently discovered quantum spin liquid candidate, the organic insulator EtMe3Sb[Pd(dmit)2]2. A sizable linear temperature dependence term is clearly resolved in the zero-temperature limit, indicating the presence of gapless excitations with an extremely long mean free path, analogous to excitations near the Fermi surface in pure metals. Its magnetic field dependence suggests a concomitant appearance of spin-gap-like excitations at low temperatures. These findings expose a highly unusual dichotomy that characterizes the low-energy physics of this quantum system. PMID:20522768
Penedo, M., E-mail: mapenedo@imm.cnm.csic.es; Hormeño, S.; Fernández-Martínez, I.; Luna, M.; Briones, F. [IMM-Instituto de Microelectrónica de Madrid (CNM-CSIC), Isaac Newton 8, PTM, E-28760 Tres Cantos, Madrid (Spain); Raman, A. [Birck Nanotechnology Center and School of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47904 (United States)
2014-10-27
Recent developments in dynamic Atomic Force Microscopy where several eigenmodes are simultaneously excited in liquid media are proving to be an excellent tool in biological studies. Despite its relevance, the search for a reliable, efficient, and strong cantilever excitation method is still in progress. Herein, we present a theoretical modeling and experimental results of different actuation methods compatible with the operation of Atomic Force Microscopy in liquid environments: ideal acoustic, homogeneously distributed force, distributed applied torque (MAC Mode™), photothermal and magnetostrictive excitation. From the analysis of the results, it can be concluded that magnetostriction is the strongest and most efficient technique for higher eigenmode excitation when using soft cantilevers in liquid media.
Excitations in a thin liquid {sup 4}He film from inelastic neutron scattering
Clements, B.E. [Department of Physics, Texas A& M University, College Station, Texas 77843 (United States)] [Department of Physics, Texas A& M University, College Station, Texas 77843 (United States); [Institute Laue Langevin, 38042 Grenoble Cedex (France); Godfrin, H. [Centre de Recherches sur les Tres Basses Temperatures, CNRS, Boite Postale 166X, 38042 Grenoble (France)] [Centre de Recherches sur les Tres Basses Temperatures, CNRS, Boite Postale 166X, 38042 Grenoble (France); Krotscheck, E. [Department of Physics, Texas A& M University, College Station, Texas 77843 (United States)] [Department of Physics, Texas A& M University, College Station, Texas 77843 (United States); [Institut fuer Theoretische Physik, Johannes Kepler Universitaet, A 4040 Linz (Austria); Lauter, H.J. [Institute Laue Langevin, 38042 Grenoble Cedex (France)] [Institute Laue Langevin, 38042 Grenoble Cedex (France); Leiderer, P. [Fachbereich Physik, Universitaet Konstanz, Konstanz (Germany)] [Fachbereich Physik, Universitaet Konstanz, Konstanz (Germany); Passiouk, V. [Institute Laue Langevin, 38042 Grenoble Cedex (France)] [Institute Laue Langevin, 38042 Grenoble Cedex (France); [Fachbereich Physik, Universitaet Konstanz, Konstanz (Germany); Tymczak, C.J. [Department of Physics, Texas A& M University, College Station, Texas 77843 (United States)] [Department of Physics, Texas A& M University, College Station, Texas 77843 (United States)
1996-05-01
We perform a thorough analysis of the experimental dynamic structure function measured by inelastic neutron scattering for a low-temperature ({ital T}=0.65 K) four-layer liquid {sup 4}He film. The results are interpreted in light of recent theoretical calculations of the (nonvortex) excitations in thin liquid Bose films. The experimental system consists of four outer liquid layers, adsorbed to two solid inner {sup 4}He layers, which are themselves adsorbed to a graphite substrate. Relatively intense surface (ripplon) and bulklike modes are observed. The analysis of the experimental data gives strong evidence for still other modes and supports the long-standing theoretical predictions of layerlike modes (layer phonons) associated with excitations propagating primarily within the liquid layers comprising the film. The results of the analysis are consistent with the occurrence of level crossings between modes, and the existence of a layer modes for which the theory predicts will propagate in the vicinity of the solid-liquid interface. The theory and experiment agree on the detailed nature of the ripplon; its dispersion at low momenta, its fall off in intensity at intermediate momenta, and the level crossings at high momentum. Similar to experiment, the theory yields an intense mode in the maxon-roton region which is intrepreted as the formation of the bulklike excitation. {copyright} {ital 1996 The American Physical Society.}
Slosh wave and geyser excitations due to liquid hydrogen shut-off during draining in microgravity
NASA Technical Reports Server (NTRS)
Hung, R. J.; Shyu, K. L.
1995-01-01
The dynamical behavior of liquid hydrogen shut-off during draining, and shut-off at the moment of the incipience of a suction dip have been investigated. It shows that a large amplitude surge is observed for liquid in the container at the moment of liquid hydrogen shut-off in reduced gravity. It also shows that slosh waves accompanied by a strong geyser are developed for surge-related flow fields induced by liquid hydrogen shut-off at the incipience of a suction dip. In the slosh wave excitation, both a lower gravity environment and higher flow rate before the shut-off of liquid draining are resonsible for the initiation of greater amplitude slosh waves. Slosh wave excitation, due to shut-off during liquid hydrogen draining, shift the fluid mass distribution in the container which imposes time-dependent variation in the spacecraft moment of inertia. This provides important information necessary for on-orbit guidance and attitude control of spacecraft.
Geometry-driven shift in the Tomonaga-Luttinger exponent of deformed cylinders
Shima, Hiroyuki [Department of Applied Physics, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628 (Japan); Yoshioka, Hideo [Department of Physics, Nara Women's University, Nara 630-8506 (Japan); Onoe, Jun [Department of Nuclear Engineering and Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro, Tokyo 152-8550 (Japan)
2009-05-15
We demonstrate the effects of geometric perturbation on the Tomonaga-Luttinger liquid (TLL) states in a long, thin, and hollow cylinder whose radius varies periodically. The variation in the surface curvature inherent to the system gives rise to a significant increase in the power-law exponent of the single- particle density of states. The increase in the TLL exponent is caused by a curvature-induced potential that attracts low-energy electrons to region that has large curvature.
Reflection and refraction of Bose-Einstein-condensate excitations
NASA Astrophysics Data System (ADS)
Watabe, Shohei; Kato, Yusuke
2008-12-01
We investigate transmission and reflection of Bose-Einstein-condensate excitations in the low-energy limit across a potential barrier separating two condensates with different densities. The Bogoliubov excitation in the low-energy limit has an incident angle where the perfect transmission occurs. This condition corresponds to Brewster’s law for the electromagnetic wave. The total internal reflection of the Bogoliubov excitation is found to occur at a large incident angle in the low-energy limit. The anomalous tunneling named by Kagan [Yu. Kagan , Phys. Rev. Lett. 90, 130402 (2003)] can be understood in terms of the impedance matching. In the case of the normal incidence, comparison with the results in Tomonaga-Luttinger liquids is made.
The extended conformal theory of Luttinger systems
M. Frau; A. Lerda; S. Sciuto; G. R. Zemba
1996-06-11
We describe the recently introduced method of algebraic bosonization of the $(1+1)$-dimensional Luttinger systems by discussing in detail the specific case of the Calogero-Sutherland model, and mentioning the hard-core Bose gas. We also compare our findings with the exact Bethe Ansatz results.
Similarity rules in gravity jitter-related spacecraft liquid propellant slosh waves excitation
NASA Astrophysics Data System (ADS)
Hung, R. J.; Lee, C. C.; Leslie, F. W.
1992-07-01
The dynamical behavior of fluids, in particular the effect of surface tension on partially filled rotating fluids in a full-scale prototype Gravity Probe-B Spacecraft propellant tank and various 10 percent subscale containers with identical values of similarity parameters such as Bond number, dynamical capillary number, rotational Reynolds number, and Weber number, as well as imposed gravity jitters have been investigated. It is shown that the Bond number can be used to simulate the wave characteristics of slosh wave excitation, whereas the Weber number can be used to simulate the wave amplitude of slosh-mode excitation. It is shown that a dynamical capillary number can be used to simulate the induced perturbation of the fluid stress distribution exerted on the wall. This distribution is governed by the interaction between surface tension (slosh-wave excitation along the liquid-vapor interface) and viscous (fluid stress exerted on the wall) forces.
Self-Consistent Model of Roton Cluster Excitations in Liquid Helium II
V. I. Kruglov; M. J. Collett
2006-05-18
We have proposed a model of roton cluster excitations in liquid helium~II based on a Schr\\"odinger-type equation with a self-consistent confining potential. We have derived an equation for the number of atoms in roton excitations, which can be treated as quantum $3{\\rm D}$ solitons, depending on vibrational quantum numbers. It is shown that the smallest roton cluster is in the symmetric vibrational quantum state and consists of 13 helium atoms. We have also used a modified Born approximation to calculate the $s$-scattering length for helium atoms. This allows us to calculate all parameters of Landau's roton excitation spectrum, in agreement to high accuracy with experimental measurements from neutron scattering.
Babu, Sukumaran Santhosh; Hollamby, Martin J.; Aimi, Junko; Ozawa, Hiroaki; Saeki, Akinori; Seki, Shu; Kobayashi, Kenji; Hagiwara, Keita; Yoshizawa, Michito; Möhwald, Helmuth; Nakanishi, Takashi
2013-01-01
Nonvolatile room-temperature luminescent molecular liquids are a new generation of organic soft materials. They possess high stability, versatile optical properties, solvent-free fluid behaviour and can effectively accommodate dopant dye molecules. Here we introduce an approach to optimize anthracene-based liquid materials, focussing on enhanced stability, fluorescence quantum yield, colour tunability and processability, with a view to flexible electronic applications. Enveloping the anthracene core in low-viscosity branched aliphatic chains results in stable, nonvolatile, emissive liquid materials. Up to 96% efficient energy-transfer-assisted tunable emission is achieved by doping a minute amount of acceptor dye in the solvent-free state. Furthermore, we use a thermoresponsive dopant to impart thermally controllable luminescence colours. The introduced strategy leading to diverse luminescence colours at a single blue-light excitation can be an innovative replacement for currently used luminescent materials, providing useful continuous emissive layers in developing foldable devices. PMID:23736114
Low-gravity liquid nonlinear sloshing analysis in a tank under pitching excitation
NASA Astrophysics Data System (ADS)
Yuanjun, He; Xingrui, Ma; Pingping, Wang; Benli, Wang
2007-01-01
Under pitch excitation, the sloshing of liquid in circular cylindrical tank includes planar motion, rotary motion and rotary motion inside planar motion. The boundaries between stable motion and unstable motion depend on the radius of the tank, the liquid height, the gravitational intension, the surface tensor and the sloshing damping. In this article, the differential equations of nonlinear sloshing are built first. And by variational principle, the Lagrange function of liquid pressure is constructed in volume integration form. Then the velocity potential function is expanded in series by wave height function at the free surface. The nonlinear equations with kinematics and dynamics free surface boundary conditions through variation are derived. At last, these equations are solved by multiple-scales method. The influence of Bond number on the global stable response of nonlinear liquid sloshing in circular cylinder tank is analyzed in detail. The result indicates that the system's amplitude-frequency response changes from a 'soft-spring' to a 'hard-spring' in the planar motion with the decreasing of the Bond number, while it changes from a 'hard-spring' to a 'soft-spring' in the rotary motion. At the same time, jump, lag and other nonlinear phenomena of liquid sloshing are discovered.
Ettore Segreto
2015-03-29
TetraPhenyl Butadiene is the wavelength shifter most widely used in combination with liquid Argon. The latter emits scintillation photons with a wavelength of 127 nm that need to be downshifted to be detected by photomultipliers with glass or quartz windows. TetraPhenyl Butadiene has been demonstrated to have an extremely high conversion efficiency, possibly higher than 100 % for 127 nm photons, while there is no precise information about the time dependence of its emission. It is usually assumed to be exponentially decaying with a characteristic time of the order of one ns, as an extrapolation from measurements with exciting radiation in the near UV. This work shows that TetraPhenyl Butadiene, when excited by 127 nm photons, reemits photons not only with a very short decay time, but also with slower ones due to triplet states de-excitations. This fact can strongly contribute to clarify the anomalies in liquid Argon scintillation light reported in literature since seventies, namely the inconsistency in the measured values of the long decay time constant and the appearance of an intermediate component. Similar effects should be also expected when the TPB is used in combination with Helium and Neon, that emit scintillation photons with wavelengths shorter than 127 nm.
T.-S. Lin; C.-P. Pang; J.-T. Lue
2002-01-01
Attenuated total reflection (ATR) is a prominent effect in examining the excitation of surface plasmons. The Kretschmann-Raether and Otto configurations are implemented to generate surface plasmons and to examine the change of the refractive index of liquid crystals (LCs) by an applied field. A mixture of nematic and cholesteric liquid crystals is sandwiched between two glass substrates coated with conducting
Two-photon excitation STED microscopy by utilizing transmissive liquid crystal devices.
Otomo, Kohei; Hibi, Terumasa; Kozawa, Yuichi; Kurihara, Makoto; Hashimoto, Nobuyuki; Yokoyama, Hiroyuki; Sato, Shunichi; Nemoto, Tomomi
2014-11-17
Transmissive liquid crystal devices (tLCDs) enable the modification of optical properties, such as phase, polarization, and laser light intensity, over a wide wavelength region at a high conversion efficiency. By utilizing tLCDs, we developed a new two-photon excitation stimulated emission depletion microscopy technique based on a conventional two-photon microscope. Spatial resolution was improved by compensating for phase shifts distributed in the optical path. Using this technique, we observed the fine structures of microtubule networks in fixed biological cells. PMID:25402061
T.-S. Lin; C.-P. Pang; J.-T. Lue
2002-01-01
. Attenuated total reflection (ATR) is a prominent effect in examining the excitation of surface plasmons. The Kretschmann–Raether\\u000a and Otto configurations are implemented to generate surface plasmons and to examine the change of the refractive index of\\u000a liquid crystals (LCs) by an applied field. A mixture of nematic and cholesteric liquid crystals is sandwiched between two\\u000a glass substrates coated with
Thermally excited fluid flow in a microsized liquid crystal channel with a free surface
NASA Astrophysics Data System (ADS)
Zakharov, A. V.; Vakulenko, A. A.
2015-06-01
The temperature-induced reorientation dynamics in microsized liquid crystal (LC) channel with a free LC/vacuum interface has been investigated theoretically based on the hydrodynamic theory including the director motion, the thermally excited fluid flow v, and the temperature T redistribution, produced by induced heating in the interior of the LC sample. Analysis of the numerical results shows that due to interaction between ?T and the gradient of the director field ? n ˆ in the LC channel bounded by the free LC/vacuum interface, a thermally excited vortical fluid flow is maintained in the vicinity of the heat source. Calculations also show that in the case of the fast heating, the LC sample settles down to three-vortical flow regime, whereas in the case of the slow heating, the LC material settles down to bi-vortical flow regime. As for nematogenic material, we have considered the LC channel to be occupied by 4-n-pentyl-4'-cyanobiphenyl and investigated the effect of both ? n ˆ and ?T on the magnitude and direction of v, as well as on the height of the LC film on the solid surface, for a number of heating and hydrodynamic regimes.
NSDL National Science Digital Library
Hot on the heels of AltaVista's Raging Search (see the May 5, 2000 Scout Report) comes another returned and (somewhat) slimmed-down search engine that focuses on relevant results. Like Raging Search, Excite's new Precision Search uses Google-style link analysis technology ("Deep Analysis") to help identify the most useful sites. Test queries produced consistently relevant results among the top few returns, though an indication of the number of total returns would be helpful, with two banner ads and (in some but not all cases) a Quick Results box on the left that could be quite handy for consumer-related searching. For instance, a search for "Plymouth" yielded links to research and comparisons, blue book values, financing, and service and repair information in the Quick Results box. I was also pleased to see that clicking on one of the other search categories (category, news, photo, audio/video) instantly produces returns for the original query, though the photo databases available seem somewhat limited compared to, say, AltaVista. While users searching for "official" sites will still do best at Google, those who also search for additional resources such as news, photos, and audio/video content may wish to give Excite Precision a run-through.
S. M. Arakelyan; G. L. Grigoryan; L. M. Kocharyan; S. Ts Nersisyan; Yu S. Chilingaryan
1987-01-01
A study was made of resonant excitation of surface plasmons at an interface between a metal and a nematic liquid crystal under conditions of self-interaction of light. The experiments yielded optically bistable characteristics of the intensity of the radiation transmitted by the system in the field of low-power cw laser radiation.
N. D. McMillan; F. E. Feeney; M. J. P. Power; S. M. Kinsella; M. P. Kelly; C. Hammil; K. W. Thompson; J. P. ODea
1994-01-01
A qualitative investigation into the viscoelastic-surface properties of pendant drops has been conducted using a new instrumental technique, the fibre drop analyser (FDA), by means of measurement of the damped vibrations in mechanically excited pendant drop for a series of pure liquids. The study reveals a range of processes in the damped vibrations of pendant drops and could open up
The Kohn-Luttinger Effect in Gauge Theories
Thomas Schaefer
2006-09-07
Kohn and Luttinger showed that a many body system of fermions interacting via short range forces becomes superfluid even if the interaction is repulsive in all partial waves. In gauge theories such as QCD the interaction between fermions is long range and the assumptions of Kohn and Luttinger are not satisfied. We show that in a U(1) gauge theory the Kohn-Luttinger phenomenon does not take place. In QCD attractive channels always exist, but there are cases in which the primary pairing channel leaves some fermions ungapped. As an example we consider the unpaired fermion in the 2SC phase of QCD with two flavors. We show that it acquires a very small gap via a mechanism analogous to the Kohn-Luttinger effect. The gap is too small to be phenomenologically relevant.
Nishida, Shuhei; Kobayashi, Dai; Sakurada, Takeo; Nakazawa, Tomonori; Hoshi, Yasuo; Kawakatsu, Hideki [Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505 (Japan)
2008-12-15
The authors present an optically based method combining photothermal excitation and laser Doppler velocimetry of higher cantilever vibration modes for dynamic atomic force microscopy in liquid. The frequency spectrum of a silicon cantilever measured in water over frequencies ranging up to 10 MHz shows that the method allows us to excite and detect higher modes, from fundamental to fifth flexural, without enhancing spurious resonances. By reducing the tip oscillation amplitude using higher modes, the average tip-sample force gradient due to chemical bonds is effectively increased to achieve high-spatial-resolution imaging in liquid. The method's performance is demonstrated by atomic resolution imaging of a mica surface in water obtained using the second flexural mode with a small tip amplitude of 99 pm; individual atoms on the surface with small height differences of up to 60 pm are clearly resolved.
The $W_{1 + \\infty }$ effective theory of the Calogero- Sutherland model and Luttinger systems.
R. Caracciolo; A. Lerda; G. R. Zemba
1995-04-01
We construct the effective field theory of the Calogero-Sutherland model in the thermodynamic limit of large number of particles $N$. It is given by a $\\winf$ conformal field theory (with central charge $c=1$) that describes {\\it exactly} the spatial density fluctuations arising from the low-energy excitations about the Fermi surface. Our approach does not rely on the integrable character of the model, and indicates how to extend previous results to any order in powers of $1/N$. Moreover, the same effective theory can also be used to describe an entire universality class of $(1+1)$-dimensional fermionic systems beyond the Calogero-Sutherland model, that we identify with the class of {\\it chiral Luttinger systems}. We also explain how a systematic bosonization procedure can be performed using the $\\winf$ generators, and propose this algebraic approach to {\\it classify} low-dimensional non-relativistic fermionic systems, given that all representations of $\\winf$ are known. This approach has the appeal of being mathematically complete and physically intuitive, encoding the picture suggested by Luttinger's theorem.
Sloshing response of nonuniform density liquid in a laterally excited tank
Tang, Y.; Chang, Y.W.
1993-10-01
A large number of high level waste (HLW) storage tanks at various facilities contain liquid with nonuniformity density. Exploratory studies show that the dynamic response of a tank containing two liquids is quite different from that of an identical tank containing only one liquid. To design and evaluate the HLW storage tanks it is necessary to understand the sloshing response of tanks that contain liquid with nonuniform density. The system considered is a circular cylindrical tank containing a liquid whose density increases with the liquid depth. The density distribution along the depth can be of any arbitrary continuous function. In the analysis, the liquid field is divided into n layers. The thicknesses of the liquid layers can be different, but the density of each liquid layer is considered to be uniform and its value is assigned to be the value of the original liquid density at the mid-height of that layer. The problem is solved by the transfer matrix technique. The effect of the nonuniform liquid density on the sloshing response is illustrated in a numerical example in which the linear and cosine distributions of the liquid density are assumed. The response functions examined include the sloshing frequencies, surface wave height, and the associated convective hydrodynamic pressure. The results are presented in tabular and graphical forms. It is found that the natural frequencies of the sloshing motion for nonuniform density liquid are lower than those of the uniform density liquid of the same total depth contained in an identical tank. Also, it is shown that for nonuniform density liquid, the maximum sloshing wave height may increase significantly and the magnitude of the convective hydrodynamic pressure may be quite different compared with that of a uniform liquid contained in an identical tank.
Excitability and pattern formation in a liquid crystal FabryPerot interferometer
Wang, Peng-Ye
features of excitability in this system when it is spatially extended, namely, propagating pulses in one and biological systems, such as Belou- sov±Zhabotinsky reaction [1] and cardiac tissues [2]. Recently excitable of nonlinear optical phenomena. Optical bistability, self-oscillation and chaos have been observed with nematic
Grigoriev, Alexei
X-ray study of the liquid potassium surface: Structure and capillary wave excitations Oleg Shpyrko the liquid surface of pure potassium. They strongly suggest the existence of atomic layering at the free that of potassium, and hence closer to inducing an ideal ``hard wall'' boundary condition. The experimental result
Wave packet dynamics in hole Luttinger systems
NASA Astrophysics Data System (ADS)
Demikhovskii, V. Ya.; Maksimova, G. M.; Frolova, E. V.
2010-03-01
For hole systems with an effective spin 3/2 we analyzed analytically and numerically the evolution of wave packets with the different initial polarizations. The dynamics of such systems is determined by the 4×4 Luttinger Hamiltonian. We work in the space of arbitrary superposition of light- and heavy-hole states of the “one-particle system.” For strong anisotropic packets in three-dimensional semiconductors we obtained the analytical solution for the components of wave function and analyzed the space-time dependence of probability densities as well as angular momentum densities. Depending on the value of the parameter a=k0d ( k0 is the average momentum vector and d is the packet width) two scenarios of evolution are realized. For a?1 the initial wave packet splits into two parts and the coordinates of packet center experience the transient oscillations or Zitterbewegung (ZB) as for other two-band systems. In the case when a?1 the distribution of probability density at t>0 remains almost cylindrically symmetric and the ripples arise at the circumference of wave packet. The ZB in this case is absent. We evaluated and visualized for different values of parameter a the space-time dependence of angular momentum densities, which have the multipole structure. It was shown that the average momentum components can precess in the absence of external or effective magnetic fields due to the interference of the light- and heavy-hole states. For localized initial states this precession has a transient character.
Holroyd, R A; Preses, J M; Hanson, J C
1993-09-01
The absorption of X rays in liquids provides low-energy electrons in the energy range 2 to 20 keV when synchrotron radiation is used as the X ray source. Such low-energy electrons have short ranges and produce a dense track of ionization where dE/dx = 10(7) to 10(8) eV/cm. Fluorescent molecules provide a sensitive probe of the early-time structure of such tracks. From the extent of quenching of excited states and the consequent decrease in fluorescence lifetimes, the concentration of free radicals in the track can be inferred. Experiments done with the hydrocarbons cis-decalin and dodecane demonstrate this effect. In both hydrocarbons, the lifetimes (tau) are significantly smaller with excitation by X rays than with UV radiation, and tau-1 increases linearly with dE/dx. PMID:8397427
Elsaesser, Thomas; Reimann, Klaus; Woerner, Michael
2015-06-01
Intense terahertz (THz) electric field transients with amplitudes up to several megavolts/centimeter and novel multidimensional techniques are the key ingredients of nonlinear THz spectroscopy, a new area of basic research. Both nonlinear light-matter interactions including the non-perturbative regime and THz driven charge transport give new insight into the character and dynamics of low-energy excitations of condensed matter and into quantum kinetic phenomena. This article provides an overview of recent progress in this field, combining an account of technological developments with selected prototype results for liquids and solids. The potential of nonlinear THz methods for future studies of low-frequency excitations of condensed-phase molecular systems is discussed as well. PMID:26049419
NASA Astrophysics Data System (ADS)
Elsaesser, Thomas; Reimann, Klaus; Woerner, Michael
2015-06-01
Intense terahertz (THz) electric field transients with amplitudes up to several megavolts/centimeter and novel multidimensional techniques are the key ingredients of nonlinear THz spectroscopy, a new area of basic research. Both nonlinear light-matter interactions including the non-perturbative regime and THz driven charge transport give new insight into the character and dynamics of low-energy excitations of condensed matter and into quantum kinetic phenomena. This article provides an overview of recent progress in this field, combining an account of technological developments with selected prototype results for liquids and solids. The potential of nonlinear THz methods for future studies of low-frequency excitations of condensed-phase molecular systems is discussed as well.
Renormalization group and the Fermi surface in the Luttinger model
G. Benfatto; G. Gallavotti; V. Mastropietro
1992-01-01
The exactly soluble Luttinger model can also be analyzed from the point of view of the renormalization group. A perturbation theory of the beta function of the model is derived. We argue that the main terms of the beta function vanish identically if the anomalous dimension is properly treated and if suitable properties of the exact solution are taken into
Renormalization group and the ultraviolet problem in the Luttinger model
G. Gentile; B. Scoppola
1993-01-01
The Luttinger model describes a non-local interacting relativistic theory for spinless and massless fermions. Albeit the exact solution is already known, the perturbative approach to the model via the renormalization group is useful on account of the connection to the study of more realistic models' behaviour near the Fermi surface. In this work we show that the effective potential describing
Ostafin, A.E.; Lipsky, S. (Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455 (United States))
1993-04-01
Fluorescence action spectra have been obtained for the neat liquids, [ital cis]-decalin, [ital trans]-decalin, bicyclohexyl, cyclohexane, methylcyclohexane, isobutylcyclohexane, 2,3,4-trimethylpentane, 2,3-dimethylbutane, 3-methylhexane, 3-methylpentane, [ital n]-decane, [ital n]-dodecane, and [ital n]-pentadecane at excitation energies, [epsilon], ranging from their absorption onsets (at ca. 7 eV) to 10.3 eV. For all compounds, with the exception of [ital cis]-decalin, the fluorescence quantum yield is observed to monotonically decline with increasing [epsilon], reaching a minimum value at an energy, [epsilon][sub [ital m
Bray, James William (Niskayuna, NY); Garces, Luis Jose (Niskayuna, NY)
2012-03-13
The disclosed technology is a cryogenic static exciter. The cryogenic static exciter is connected to a synchronous electric machine that has a field winding. The synchronous electric machine is cooled via a refrigerator or cryogen like liquid nitrogen. The static exciter is in communication with the field winding and is operating at ambient temperature. The static exciter receives cooling from a refrigerator or cryogen source, which may also service the synchronous machine, to selected areas of the static exciter and the cooling selectively reduces the operating temperature of the selected areas of the static exciter.
NASA Astrophysics Data System (ADS)
Lin, T.-S.; Pang, C.-P.; Lue, J.-T.
Attenuated total reflection (ATR) is a prominent effect in examining the excitation of surface plasmons. The Kretschmann-Raether and Otto configurations are implemented to generate surface plasmons and to examine the change of the refractive index of liquid crystals (LCs) by an applied field. A mixture of nematic and cholesteric liquid crystals is sandwiched between two glass substrates coated with conducting films. The minimum ATR angle changes by only 1° as the applied voltage increases to as much as 30 V (corresponding to 6×105 Vm-1), which does not agree with the calculation based on field-induced refractive-index change. This fact suggests that the orientation of LC molecules adjacent to an electrode surface is unaffected by the external field because of the strong-anchoring effect. A Jones-matrix simulation together with a multilayered structure of a LC clearly adduces this fact.
Violation of Luttinger's Theorem in Strongly Correlated Electronic Systems Within a 1/N Expansion
NASA Astrophysics Data System (ADS)
Cappelluti, Emmanuele; Zeyher, Roland
We study the 1/N expansion of a generic, strongly correlated electron model (SU(N) symmetric Hubbard model with U=? and N degrees of freedom per lattice site) in terms of X operators. The leading order of the expansion describes a usual Fermi liquid with renormalized, stable particles. The next-to-leading order violates Luttinger's theorem if a finite convergence radius for the 1/N expansion for a fixed and non-vanishing doping away from half-filling is assumed. We find that the volume enclosed by the Fermi surface, is at large, but finite N's and small dopings larger than at N=?. As a by-product an explicit expression for the electronic self-energy in O(1/N) is given which cannot be obtained by factorization or mode-coupling assumptions but contains rather sophisticated vertex corrections.
Ward Identities and Chiral Anomaly in the Luttinger Liquid
Giuseppe Benfatto; Vieri Mastropietro
2005-01-01
Systems of interacting non-relativistic fermions in d =1, as well as spin chains or interacting two dimensional Ising models, verify an hidden approximate Gauge invariance which can be used to derive suitable Ward identities. Despite the presence of corrections and anomalies, such Ward identities can be implemented in a Renormalization Group approach and used to exploit nontrivial cancellations which allow
Wentzel-Bardeen singularity in coupled Luttinger liquids: Transport properties
Martin, T.
1994-08-26
The recent progress on 1 D interacting electrons systems and their applications to study the transport properties of quasi one dimensional wires is reviewed. We focus on strongly correlated elections coupled to low energy acoustic phonons in one dimension. The exponents of various response functions are calculated, and their striking sensitivity to the Wentzel-Bardeen singularity is discussed. For the Hubbard model coupled to phonons the equivalent of a phase diagram is established. By increasing the filling factor towards half filling the WB singularity is approached. This in turn suppresses antiferromagnetic fluctuations and drives the system towards the superconducting regime, via a new intermediate (metallic) phase. The implications of this phenomenon on the transport properties of an ideal wire as well as the properties of a wire with weak or strong scattering are analyzed in a perturbative renormalization group calculation. This allows to recover the three regimes predicted from the divergence criteria of the response functions.
Luttinger-Liquid Phenomenology for High-Tc Superconductors
NASA Astrophysics Data System (ADS)
Byczuk, K.; Spalek, J.; Wojcik, W.
1998-12-01
Universal scaling with temperature of the resistivity and optical conductivity in the normal state follows from the time-reversal symmetry assumed for the Green function with branch cuts combined with charge-spin separation. The density of states reproduces the extended van Hove singularity in a planar system. The single-particle tunneling conductivity in the superconducting state is nonzero at zero bias voltage, reproducing the pseudogap character of the density of states in the superconducting phase even for the s-wave symmetry of the order parameter. The form of the Ginzburg--Landau functional is also provided.
Experimental Evidence for Resonant Tunneling in a Luttinger Liquid
O. M. Auslaender; A. Yacoby; R. de Picciotto; K. W. Baldwin; L. N. Pfeiffer; K. W. West
2000-01-01
We have measured the low temperature conductance of a one-dimensional island\\u000aembedded in a single mode quantum wire. The quantum wire is fabricated using\\u000athe cleaved edge overgrowth technique and the tunneling is through a single\\u000astate of the island. Our results show that while the resonance line shape fits\\u000athe derivative of the Fermi function the intrinsic line width
Conservation laws and correlation functions in the Luttinger liquid
Walter Metzner; Carlo di Castro
1993-01-01
The low-energy properties of interacting Fermi systems are highly constrained by conservation laws. They generally simplify the structure of the underlying renormalization group by reducing the number of independent renormalization constants. In one dimension, all properties of normal metallic fixed points are uniquely determined by separate charge and spin conservation for states near the left and right Fermi points, respectively.
Fractional shot noise in partially gapped Tomonaga-Luttinger liquids
NASA Astrophysics Data System (ADS)
Cornfeld, Eyal; Neder, Izhar; Sela, Eran
2015-03-01
We depict a family of one-dimensional systems where one can create and detect fractional charges. These charges are produced via interacting one-dimensional conductors connected to noninteracting leads. At certain electron densities, some distinct modes develop an energy gap due to electron-electron interactions. This gap allows for tunneling events inside the conductor, which generate electric current noise. The resulting fractional noise's Fano factor depends only on the identification of the gapped mode, and is insensitive to additional interactions in the conductor. These effects can be realized in either quantum wires or edges of quantum Hall systems.
Suppression of vortex-excited vibration of tall buildings using tuned liquid dampers
C. C. Chang; M. Gu
1999-01-01
The objective of this paper is to study the control effects of rectangular TLDs installed on a tall building that vibrates due to vortex excitation. Optimal design properties of these TLDs and their control performance are first obtained using the characteristic equation of the TLD-building system. Wind tunnel experiments are performed on a scaled-down building model equipped with rectangular TLDs
The Four-Wave Mixing and the Hydrodynamic Excitations in Smectic A Liquid Crystals
G. F. Kventsel; B. I. Lembrikov
1995-01-01
A nondegenerate four-wave mixing (FWM) on a new type of Kerr nonlinearity determined by the layer deformations in smectic A liquid crystal (SmA) is considered. It is shown that in the case when the frequency difference of the coupled electromagnetic waves (EMW) is close to the frequency of the second sound (SS), a strong parametric coupling among EMW through the
Bosonic description of a Tomonaga-Luttinger model with impurities
Victoria Fernandez; Kang Li; Carlos Naon
1999-02-26
We extend a recently proposed non-local version of Coleman's equivalence between the Thirring and sine-Gordon models to the case in which the original fermion fields interact with fixed impurities. We explain how our results can be used in the context of one-dimensional strongly correlated systems (the so called Tomonaga-Luttinger model) to study the dependence of the charge-density oscillations on the range of the fermionic interactions.
Bosonic description of a Tomonaga-Luttinger model with impurities
NASA Astrophysics Data System (ADS)
Fernández, Victoria; Li, Kang; Naón, Carlos
1999-04-01
We extend a recently proposed non-local version of Coleman's equivalence between the Thirring and sine-Gordon models to the case in which the original fermion fields interact with fixed impurities. We explain how our results can be used in the context of one-dimensional strongly correlated systems (the so called Tomonaga-Luttinger model) to study the dependence of the charge-density oscillations on the range of the fermionic interactions.
Bosonic description of a Tomonaga-Luttinger model with impurities
Fernández, V; Naón, C M; Fernandez, Victoria; Li, Kang; Naon, Carlos
1999-01-01
We extend a recently proposed non-local version of Coleman's equivalence between the Thirring and sine-Gordon models to the case in which the original fermion fields interact with fixed impurities. We explain how our results can be used in the context of one-dimensional strongly correlated systems (the so called Tomonaga-Luttinger model) to study the dependence of the charge-density oscillations on the range of the fermionic interactions.
Spectral functions for the Tomonaga-Luttinger model
V. Meden; K. nhammer
1992-01-01
Results for the one-particle Green's function for the Tomonaga-Luttinger model of one-dimensional interacting fermions take a simple form using space and time variables. To obtain the corresponding spectral functions which determine photoemission and inverse-photoemission spectra, a double Fourier transform is necessary. For the model including spin we present analytical and numerical results. They show drastic differences from the spinless case.
Bose-Einstein Condensation in the Luttinger-Sy Model
Olivier Lenoble; Valentin A. ZAGREBNOV
2006-01-01
We present a rigorous study of the Bose-Einstein condensation in the Luttinger-Sy model. We prove the existence of the condensation in this one-dimensional model of the perfect boson gas placed in the Poisson random potential of singular point impurities. To tackle the off-diagonal long-range order we calculate explicitly the corresponding space-averaged one-body reduced density matrix. We show that mathematical mechanism
Fermi surfaces and Luttinger's theorem in paired fermion systems
Subir Sachdev; Kun Yang
2006-05-08
We discuss ground state properties of a mixture of two fermion species which can bind to form a molecular boson. When the densities of the fermions are unbalanced, one or more Fermi surfaces can appear: we describe the constraints placed by Luttinger's theorem on the volumes enclosed by these surfaces in such Bose-Fermi mixtures. We also discuss the nature of the quantum phase transitions involving changes in the number of Fermi surfaces.
D. Ebeling; H. Hölscher
2007-01-01
The constant-excitation mode of the frequency modulation technique can be used to perform atomic force microscopy experiments in vacuum, air, and liquids. Adding an additional Q-Control feedback to the cantilever driving the effective Q-factor of the cantilever can be increased. This is especially useful for applications in air and liquids where the cantilever is damped by the surrounding medium. Here,
A Study of Elementary Excitations of Liquid Helium-4 Using Macro-orbital Microscopic Theory
Yatendra S. Jain
2006-09-18
Energy of elementary excitations and the anomalous nature of small Q phonons in He-II are studied by using our macro-orbital microscopic theory of a system of interacting bosons (cond-mat/0606571). It is observed that : (i) the experimental E(Q) of He-II not only agrees with our theoretical relation $E(Q) = \\hbar^2Q^2/4mS(Q)$ but also supports an important conclusion of Price that S(0) should have zero value for quantum fluids, and (ii) Feynman's energy of excitations $E(Q)_{Fyn} = \\hbar^2Q^2/2mS(Q)$ equals approximately to $2E(Q)_{exp}$ even at low Q. Three problems with the Feynman's inference that $E(Q)_{Fyn}$ has good agreement with $E(Q)_{exp}$ at low Q are identified. It is argued that the theory can also be used to understand similar spectrum of the BEC state of a dilute gas reported by O'Dell et al.
Edge Excitations of an Incompressible Fermionic Liquid in a Disorder Magnetic Field
A. Sedrakyan
1998-06-25
The model of lattice fermions in 2+1 dimensional space is formulated, the critical states of which are lying in the basis of such physical problems, as 3D Ising Model(3DIM) and the edge excitations in the Hall effect. The action for this exitations coincides with the action of so called sign-factor model in 3DIM at one values of its parameters, and represent a model for the edge excitations, which are responsible for the plato transitions in the Hall effect, at other values. The model can be formulated also as a loop gas models in 2D, but unlikely the O(n) models, where the loop fugacity is real, here we have directed (clochwise and conterclochwise) loops and phase factors $e^{\\pm 2\\pi {p \\over q} i}$ for them. The line of phase transitions in the parametric space will be found and corresponding continuum limits of this models will be constructed. It appears, that besides the ordinary critical line, which separates the dense and diluted phases of the models(like in ordinary O(n) models), there is a line, which corresponds to the full covering of the space by curves. The N=2 twisted superconformal models with SU(2)/U(1) coset model coupling constant $k={q \\over p}-2$ describes this states.
Photo-excited states in germanium at liquid-helium temperatures
Culbertson, J.C.
1982-12-01
A wide variety of experimental work dealing with the basic properties of photoexcited states in Ge at liquid helium temperatures is presented. The primary emphasis is on the electron-hole liquid (EHL) and the free exciton (FE). The EHL is composed of two interpenetrating Fermi liquids, one of electrons and one of holes, each with its own Fermi level. The FE dealt with here is a mobile, loosely bound state of an electron and a hole. We report the first absolute measurement of the density dependence of the enhancement factor g/sub eh/(0) for the EHL in Ge. This factor g/sub eh/(0) is a measure of the electron-hole spatial correlation function, and provides a valuable and sensitive test for the predictions of various many-body-theory approximations. An EHL droplet - FE gas system confined to a strain induced potential well was used. The measurement approach relied on only a few simple and verifiable assumptions. A byproduct of this work was the measurement as a function of stress of: the electron and hole Fermi levels E/sub F//sup e/ and E/sub F//sup h/, the EHL density n/sub l/, the condensation energy phi of a FE relative to the EHL, and the binding energy of a FE (E/sub x/) relative to free carriers (FC). The decay of a FE-FC system confined to a strain induced potential well is studied. The first direct measurement of the FE diffusivity D/sub x/ is reported. The evolution in time of spatial profiles of FE luminescence were measured. From these FE density profiles, D/sub x/(4.2K) approx. = to 300 cm/sup 2/ s/sup -1/, the surface recombination velocity S approx. = 3000 cm s/sup -1/, and the FE lifetime tau/sub x/ = 27 ..mu..s with surface effects excluded were determined. (WHK)
Ground states and quasiparticle excitations of the Anderson lattice model
B. H. Brandow
1985-01-01
A variational method described previously has been extended to provide a simple and explicit realization of the Luttinger picture of a periodic Fermi liquid. The result can also be viewed as a renormalized band theory. This provides a general framework for understanding the electronic structure of periodic valence fluctuation systems.
Cartwright, Julyan H E; Checa, Antonio G; Escribano, Bruno; Sainz-Díaz, C Ignacio
2009-06-30
Nacre is an exquisitely structured biocomposite of the calcium carbonate mineral aragonite with small amounts of proteins and the polysaccharide chitin. For many years, it has been the subject of research, not just because of its beauty, but also to discover how nature can produce such a superior product with excellent mechanical properties from such relatively weak raw materials. Four decades ago, Wada [Wada K (1966) Spiral growth of nacre. Nature 211:1427] proposed that the spiral patterns in nacre could be explained by using the theory Frank [Frank F (1949) The influence of dislocations on crystal growth. Discuss Faraday Soc 5:48-54] had put forward of the growth of crystals by means of screw dislocations. Frank's mechanism of crystal growth has been amply confirmed by experimental observations of screw dislocations in crystals, but it is a growth mechanism for a single crystal, with growth fronts of molecules. However, the growth fronts composed of many tablets of crystalline aragonite visible in micrographs of nacre are not a molecular-scale but a mesoscale phenomenon, so it has not been evident how the Frank mechanism might be of relevance. Here, we demonstrate that nacre growth is organized around a liquid-crystal core of chitin crystallites, a skeleton that the other components of nacre subsequently flesh out in a process of hierarchical self-assembly. We establish that spiral and target patterns can arise in a liquid crystal formed layer by layer through the Burton-Cabrera-Frank [Burton W, Cabrera N, Frank F (1951) The growth of crystals and the equilibrium structure of their surfaces. Philos Trans R Soc London Ser A 243:299-358] dynamics, and furthermore that this layer growth mechanism is an instance of an important class of physical systems termed excitable media. Artificial liquid crystals grown in this way may have many technological applications. PMID:19528636
Minimal-excitation states for electron quantum optics using levitons.
Dubois, J; Jullien, T; Portier, F; Roche, P; Cavanna, A; Jin, Y; Wegscheider, W; Roulleau, P; Glattli, D C
2013-10-31
The on-demand generation of pure quantum excitations is important for the operation of quantum systems, but it is particularly difficult for a system of fermions. This is because any perturbation affects all states below the Fermi energy, resulting in a complex superposition of particle and hole excitations. However, it was predicted nearly 20 years ago that a Lorentzian time-dependent potential with quantized flux generates a minimal excitation with only one particle and no hole. Here we report that such quasiparticles (hereafter termed levitons) can be generated on demand in a conductor by applying voltage pulses to a contact. Partitioning the excitations with an electronic beam splitter generates a current noise that we use to measure their number. Minimal-excitation states are observed for Lorentzian pulses, whereas for other pulse shapes there are significant contributions from holes. Further identification of levitons is provided in the energy domain with shot-noise spectroscopy, and in the time domain with electronic Hong-Ou-Mandel noise correlations. The latter, obtained by colliding synchronized levitons on a beam splitter, exemplifies the potential use of levitons for quantum information: using linear electron quantum optics in ballistic conductors, it is possible to imagine flying-qubit operation in which the Fermi statistics are exploited to entangle synchronized electrons emitted by distinct sources. Compared with electron sources based on quantum dots, the generation of levitons does not require delicate nanolithography, considerably simplifying the circuitry for scalability. Levitons are not limited to carrying a single charge, and so in a broader context n-particle levitons could find application in the study of full electron counting statistics. But they can also carry a fraction of charge if they are implemented in Luttinger liquids or in fractional quantum Hall edge channels; this allows the study of Abelian and non-Abelian quasiparticles in the time domain. Finally, the generation technique could be applied to cold atomic gases, leading to the possibility of atomic levitons. PMID:24153178
Singlet-Triplet Excitations and Long-Range Entanglement in the Spin-Orbital Liquid Candidate FeSc2S4
NASA Astrophysics Data System (ADS)
Laurita, N. J.; Deisenhofer, J.; Pan, LiDong; Morris, C. M.; Schmidt, M.; Johnsson, M.; Tsurkan, V.; Loidl, A.; Armitage, N. P.
2015-05-01
Theoretical models of the spin-orbital liquid (SOL) FeSc2S4 have predicted it to be in close proximity to a quantum critical point separating a spin-orbital liquid phase from a long-range ordered magnetic phase. Here, we examine the magnetic excitations of FeSc2S4 through time-domain terahertz spectroscopy under an applied magnetic field. At low temperatures an excitation emerges that we attribute to a singlet-triplet excitation from the SOL ground state. A threefold splitting of this excitation is observed as a function of applied magnetic field. As singlet-triplet excitations are typically not allowed in pure spin systems, our results demonstrate the entangled spin and orbital character of singlet ground and triplet excited states. Using experimentally obtained parameters we compare to existing theoretical models to determine FeSc2S4's proximity to the quantum critical point. In the context of these models, we estimate the characteristic length of the singlet correlations to be ? /(a /2 )?8.2 (where a /2 is the nearest neighbor lattice constant), which establishes FeSc2S4 as a SOL with long-range entanglement.
Laurita, N J; Deisenhofer, J; Pan, LiDong; Morris, C M; Schmidt, M; Johnsson, M; Tsurkan, V; Loidl, A; Armitage, N P
2015-05-22
Theoretical models of the spin-orbital liquid (SOL) FeSc_{2}S_{4} have predicted it to be in close proximity to a quantum critical point separating a spin-orbital liquid phase from a long-range ordered magnetic phase. Here, we examine the magnetic excitations of FeSc_{2}S_{4} through time-domain terahertz spectroscopy under an applied magnetic field. At low temperatures an excitation emerges that we attribute to a singlet-triplet excitation from the SOL ground state. A threefold splitting of this excitation is observed as a function of applied magnetic field. As singlet-triplet excitations are typically not allowed in pure spin systems, our results demonstrate the entangled spin and orbital character of singlet ground and triplet excited states. Using experimentally obtained parameters we compare to existing theoretical models to determine FeSc_{2}S_{4}'s proximity to the quantum critical point. In the context of these models, we estimate the characteristic length of the singlet correlations to be ?/(a/2)?8.2 (where a/2 is the nearest neighbor lattice constant), which establishes FeSc_{2}S_{4} as a SOL with long-range entanglement. PMID:26047249
Yang, Yifeng [Los Alamos National Laboratory; Urbano, Ricardo [NHMFL, FL; Nicholas, Curro [UC DAVIS; Pines, David [UC DAVIS
2009-01-01
We report Knight shift experiments on the superconducting heavy electron material CeCoIn{sub 5} that allow one to track with some precision the behavior of the heavy electron Kondo liquid in the superconducting state with results in agreement with BCS theory. An analysis of the {sup 115}In nuclear quadrupole resonance (NQR) spin-lattice relaxation rate T{sub 1}{sup -1} measurements under pressure reveals the presence of 2d magnetic quantum critical fluctuations in the heavy electron component that are a promising candidate for the pairing mechanism in this material. Our results are consistent with an antiferromagnetic quantum critical point (QCP) located at slightly negative pressure in CeCoIn{sub 5} and provide additional evidence for significant similarities between the heavy electron materials and the high T{sub c} cuprates.
Electronic excited states as a probe of surface adsorbate structure and dynamics in liquid xenon
Peterson, E.S.
1992-08-01
A combination of second harmonic generation (SHG) and a simple dipole-dipole interaction model is presented as a new technique for determining adsorbate geometries on surfaces. The polarization dependence of SHG is used to define possible geometries of the adsorbate about the surface normal. Absorption band shifts using geometry constraints imposed by SHG data are derived for a dimer constructed from two arbitrarily placed monomers on the surface using the dipole-dipole interaction potential. These formulae can be used to determine the orientation of the two monomers relative to each other. A simplified version of this formalism is used to interpret absorption band shifts for rhodamine B adsorbed on fused silica. A brief history of the exciton is given with particular detail to Xe. Data are presented for transient absorption at RT in liquid xenon on the picosecond time scale. These are observations of both tunneling through the barrier that separates the free and trapped exciton states and the subsequent trapping of the exciton. In high densities both of these processes are found to occur within 2 to 6 picoseconds in agreement with theories of Kmiecik and Schreiber and of Martin. A threshold density is observed that separates relaxation via single binary collisions and relaxation that proceeds via Martin's resonant energy transfer hopping mechanism.
Electronic excited states as a probe of surface adsorbate structure and dynamics in liquid xenon
Peterson, E.S.
1992-08-01
A combination of second harmonic generation (SHG) and a simple dipole-dipole interaction model is presented as a new technique for determining adsorbate geometries on surfaces. The polarization dependence of SHG is used to define possible geometries of the adsorbate about the surface normal. Absorption band shifts using geometry constraints imposed by SHG data are derived for a dimer constructed from two arbitrarily placed monomers on the surface using the dipole-dipole interaction potential. These formulae can be used to determine the orientation of the two monomers relative to each other. A simplified version of this formalism is used to interpret absorption band shifts for rhodamine B adsorbed on fused silica. A brief history of the exciton is given with particular detail to Xe. Data are presented for transient absorption at RT in liquid xenon on the picosecond time scale. These are observations of both tunneling through the barrier that separates the free and trapped exciton states and the subsequent trapping of the exciton. In high densities both of these processes are found to occur within 2 to 6 picoseconds in agreement with theories of Kmiecik and Schreiber and of Martin. A threshold density is observed that separates relaxation via single binary collisions and relaxation that proceeds via Martin`s resonant energy transfer hopping mechanism.
Finite Temperature Transport in a Non-Fermi Liquid Phase of a Quadratic Semimetal
NASA Astrophysics Data System (ADS)
Dumitrescu, Philipp
2015-03-01
We study finite temperature transport in the Luttinger-Abrikosov-Beneslavskii phase - an interacting, scale invariant, non-Fermi liquid phase found in quadratic semimetals which has been recently suggested to be realized in strongly correlated pyrochlore iridate systems. We develop a kinetic equation formalism to describe the d.c. transport properties, which are dominated by collisions, and consider the shear viscosity ? as a model transport coefficient. The ratio of shear viscosity to entropy density ? / s is a measure of the strength of interaction between the excitations of a quantum fluid. As a consequence of the quantum critical nature of the system, ? / s is a universal number and we find it to be consistent with a bound proposed from gauge-gravity duality.
NASA Astrophysics Data System (ADS)
Maiti, K.; Singh, R. S.; Medicherla, V. R. R.
2007-04-01
We investigate the temperature evolution of the electronic states in the vicinity of the Fermi level of a non-Fermi-liquid (NFL) system, CaRuO3 using ultra high-resolution photoemission spectroscopy; isostructural SrRuO3 exhibiting Fermi-liquid behavior despite similar electron interaction parameters as that of CaRuO3, is used as a reference. High-energy resolution in this study helps to reveal particle-hole asymmetry in the excitation spectra of CaRuO3 in contrast to that in SrRuO3. In addition, we observe signature of phonon excitations in the photoemission spectra of CaRuO3 at finite temperatures while these are weak in SrRuO3.
Singlet-triplet excitations and long range entanglement in the spin-orbital liquid candidate FeSc2S4
NASA Astrophysics Data System (ADS)
Laurita, N. J.; Deisenhofer, J.; Pan, Lidong; Morris, C. M.; Schmidt, M.; Johnsson, M.; Tsurkan, V.,; Loidl, A.; Armitage, N. P.
2015-03-01
Theoretical models of the spin-orbital liquid (SOL) FeSc2S4 have predicted it to be in close proximity to a quantum critical point separating a spin-orbital liquid phase from a long-range ordered magnetic phase. Here, we examine the magnetic excitations of FeSc2S4 through time-domain terahertz spectroscopy under an applied magnetic field. At low temperatures an excitation emerges that we attribute to a singlet-triplet excitation from the SOL ground state. A three-fold splitting of this excitation is observed as a function of applied magnetic field. Using experimentally obtained parameters we compare to existing theoretical models to determine FeSc2S4's proximity to the quantum critical point and establish FeSc2S4 as a SOL with long-range entanglement. Work at Johns Hopkins was supported by the Gordon and Betty Moore Foundation through Grant GBMF2628, the DOE-BES through DE-FG02-08ER46544, and the ARCS Foundation.
Sasmal, Dibyendu Kumar; Mojumdar, Supratik Sen; Adhikari, Aniruddha; Bhattacharyya, Kankan
2010-04-01
The deuterium isotope effect on the solvation dynamics and the anisotropy decay of coumarin 480 (C480) in a room temperature ionic liquid (RTIL) microemulsion is studied by femtosecond up-conversion. The microemulsion consists of the RTIL 1-pentyl-3-methyl-imidazolium tetra-fluoroborate ([pmim][BF(4)]) in triton X-100 (TX-100)/benzene. Replacement of H(2)O by D(2)O in the microemulsion causes retardation of solvation dynamics. The average solvation time of C480 (tau(s)) in RTIL microemulsion with 5 wt % D(2)O is approximately 1.5-1.7 times slower compared to that in the H(2)O containing RTIL microemulsion. This suggests that the main species in the microemulsion responsible for solvation is the water molecules. In both D(2)O and H(2)O containing RTIL microemulsion, the solvation dynamics exhibits marked dependence on the excitation wavelength (lambda(ex)) and becomes about 15 times faster as lambda(ex) increases from 375 to 435 nm. This is ascribed to the structural heterogeneity in the RTIL microemulsion. For lambda(ex) = 375 nm, the region near the TX-100 surfactant is probed where bound water molecules cause slow solvation dynamics. At 435 nm, the RTIL pool is selected where the water molecules are more mobile and hence gives rise to faster solvation. The average time constant of anisotropy decay shows opposite dependence on lambda(ex) and increases about 2.5-fold from 180 ps at lambda(ex) = 375 nm to 500 ps at lambda(ex) = 435 nm for D(2)O containing RTIL microemulsion. The slower anisotropy decay at lambda(ex) = 435 nm is ascribed to the higher viscosity of RTIL which causes greater friction at the core. PMID:20235504
Luttinger's approach to thermal transport in nanoscale conductors
NASA Astrophysics Data System (ADS)
Eich, F. G.; Principi, A.; di Ventra, M.; Vignale, G.
2015-03-01
The description of thermoelectric transport from first principles has recently attracted renewed interest due to its potential role in the development of sustainable energy sources. We will present our recent work comparing Luttinger's approach to thermal transport to the widely used Landauer-Büttiker formalism. We show that they coincide in the linear regime and highlight their differences in the nonlinear regime. Moreover, we discuss the asymptotic (steady state) and transient currents for a simple two-terminal setup. We will put these results in context with our recently proposed thermal Density-Functional Theory and discuss strategies to define a local temperature. We gratefully acknowledge support from DOE under Grant Nos. DE-FG02-05ER46203 and DE-FG02-05ER46204.
Regeta, Khrystyna; Bannwarth, Christoph; Grimme, Stefan; Allan, Michael
2015-06-28
The technique of low energy (0-30 eV) electron impact spectroscopy, originally developed for gas phase molecules, is applied to room temperature ionic liquids (IL). Electron energy loss (EEL) spectra recorded near threshold, by collecting 0-2 eV electrons, are largely continuous, assigned to excitation of a quasi-continuum of high overtones and combination vibrations of low-frequency modes. EEL spectra recorded by collecting 10 eV electrons show predominantly discrete vibrational and electronic bands. The vibrational energy-loss spectra correspond well to IR spectra except for a broadening (?0.04 eV) caused by the liquid surroundings, and enhanced overtone activity indicating a contribution from resonant excitation mechanism. The spectra of four representative ILs were recorded in the energy range of electronic excitations and compared to density functional theory multireference configuration interaction (DFT/MRCI) calculations, with good agreement. The spectra up to about 8 eV are dominated by ?-?* transitions of the aromatic cations. The lowest bands were identified as triplet states. The spectral region 2-8 eV was empty in the case of a cation without ? orbitals. The EEL spectrum of a saturated solution of methylene green in an IL band showed the methylene green EEL band at 2 eV, indicating that ILs may be used as a host to study nonvolatile compounds by this technique in the future. PMID:26018044
Mandal, Sarthak; Ghosh, Surajit; Banerjee, Chiranjib; Kuchlyan, Jagannath; Banik, Debasis; Sarkar, Nilmoni
2013-03-21
In this work we have reported the formulation of a novel ionic liquid-in-oil (IL/O) microemulsion where the polar core of the ionic liquid, 1-ethyl-3-methylimidazolium n-butylsulfate ([C2mim][C4SO4]), is stabilized by a mixture of two nontoxic nonionic surfactants, polyoxyethylene sorbitan monooleate (Tween-80) and sorbitan laurate (Span-20), in a biological oil phase of isopropyl myristate (IPM). The formation of the microemulsion droplets has been confirmed from the dynamic light scattering (DLS) and phase behavior study. To assess the dynamic heterogeneity of this tween-based IL/O microemulsion, we have performed an excitation wavelength dependent fluorescence resonance energy transfer (FRET) from coumarin 480 (C480) to rhodamine 6G (R6G). The multiple donor-acceptor (D-A) distances, ?15, 30, and 45 Å, obtained from the rise times of the acceptor emission in the presence of a donor can be rationalized from the varying distribution of the donor, C480, in the different regions of the microemulsion system. With increasing the excitation wavelength from 375 to 408 nm, the contribution of the rise component of ?240 ps which results the D-A distance of ?30 Å increases significantly due to the enhanced contribution of the C480 probe molecules closer to the acceptor in the ionic liquid pool of the microemulsion. PMID:23445434
Phonon-Induced Resistivity of Electron Liquids in Quantum Wires
NASA Astrophysics Data System (ADS)
Seelig, Georg; Matveev, K. A.; Andreev, A. V.
2005-02-01
We study the resistivity of a quantum wire caused by backscattering of electrons by acoustic phonons. In the presence of Coulomb interactions, backscattering is strongly enhanced at low temperatures due to Luttinger liquid effects. Information about the strength of the interactions can be obtained from a measurement of the temperature dependence of the resistivity.
Excitation spectra and correlation functions of quantum Su-Schrieffer-Heeger models
NASA Astrophysics Data System (ADS)
Weber, Manuel; Assaad, Fakher F.; Hohenadler, Martin
2015-06-01
We study one-dimensional Su-Schrieffer-Heeger (SSH) models with quantum phonons using a continuous-time quantum Monte Carlo method. Within statistical errors, we obtain identical results for the SSH model with acoustic phonons, and a related model with a coupling to an optical bond phonon mode. Based on this agreement, we first study the Peierls metal-insulator transition of the spinless SSH model, and relate it to the Kosterlitz-Thouless transition of a spinless Luttinger liquid. In the Peierls phase, the spectral functions reveal the single-particle and charge gap, and a central peak related to long-range order. For the spinful SSH model, which has a dimerized ground state for any nonzero coupling, we reveal a symmetry-related degeneracy of spin and charge excitations, and the expected spin and charge gaps as well as a central peak. Finally, we study the SSH-U V model with electron-phonon and electron-electron interaction. We observe a Mott phase with critical spin and bond correlations at weak electron-phonon coupling, and a Peierls phase with gapped spin excitations at strong coupling. We relate our findings to the extended Hubbard model, and discuss the physical origin of the agreement between optical and acoustic phonons.
Vladimir V. Danilov; O. B. Danilov; A. I. Sidorov; E. N. Sosnov
1991-01-01
It is shown that the profile of the beam from a compact TEA CO2 laser can be controlled by an apodizing liquid-crystal stop utilizing a cholesteric-nematic transition. It is reported that the optoacoustic effect in the liquid crystal influences the mode composition and profile of the lasing pulses.
Walton, A P; Wei, G T; Liang, Z; Michel, R G; Morris, J B
1991-02-01
The coupling of a high-performance liquid chromatograph with a sensitive and selective laser-excited atomic fluorescence spectrometry (LEAFS) detector is described. In connection with this, a study of the signal and noise characteristics of instrumentation for dispersive, nondispersive, and front surface LEAFS is reported together with a comparison of the sensitivity and selectivity achieved with high-performance liquid chromatography (HPLC)-flame LEAFS, HPLC-ultraviolet (UV), and HPLC-continuum source excited flame atomic fluorescence spectrometry (AFC) instrumentation. The HPLC-flame LEAFS instrumentation was applied to an investigation of the Mn species responsible for (methylcyclopentadienyl)manganese tricarbonyl (MMT) toxicity in rats. The detection limits for various organomanganese species by HPLC-flame LEAFS ranged from 8 to 22 pg of manganese. Recovery of these compounds from rat urine varied between 80% and 100%, with a reproducibility of between 4% and 8% relative standard deviation. Preliminary data for the HPLC-flame LEAFS determination of toxic alkyltin compounds are reported. PMID:1824009
Banerjee, Chiranjib; Kundu, Niloy; Ghosh, Surajit; Mandal, Sarthak; Kuchlyan, Jagannath; Sarkar, Nilmoni
2013-08-15
In this article we have reported the fluorescence resonance energy transfer (FRET) study in our earlier characterized surface active ionic liquids (SAILs)-containing microemulsion, i.e., N-methyl-N-propylpyrrolidinium bis(trifluoromethanesulfonyl)imide ([P13][Tf2N])/[CTA][AOT]/isopropyl myristate ([IPM]) and N,N,N-trimethyl-N-propylammonium bis(trifluoromethanesulfonyl)imide ([N3111][Tf2N])/[CTA][AOT]/[IPM] microemulsions (Banerjee, C.; Mandal, S.; Ghosh, S.; Kuchlyan, J.; Kundu, N.; Sarkar, N. J. Phys. Chem. B 2013, 117, 3927-3934). The occurrence of effective FRET from the donor, coumarin-153 (C-153) to the acceptor rhodamine 6G (R6G) is evident from the decrease in the steady state fluorescence intensity of the donor with addition of acceptor and subsequent increase in the fluorescence intensity of the acceptor in the presence of donor. The excitation wavelength dependent FRET from C-153 to R6G has also been performed to assess the dynamic heterogeneity of these confined systems. In time-resolved experiments, the significant rise time of the acceptor in the presence of the donor further confirms the occurrence of FRET. The multiple donor-acceptor (D-A) distances, for various microemulsions, obtained from the rise times of the acceptor emission in the presence of a donor can be rationalized from the varying distribution of the donor, C-153, in the different regions of the microemulsion. Time-resolved measurement reveals that with increasing excitation wavelength from 408 to 440 nm, the contribution of the faster rise component of FRET increases significantly due to the close proximity of the C-153 and R6G in the polar region of the microemulsion where occurrence of FRET is very high. Moreover, we have also studied the FRET with variation of R (R = [room temperature ionic liquids (RTILs)]/[surfactant]) and shown that the effect of excitation wavelength on FRET is similar irrespective of R values. PMID:23865472
Kazuie Kimura; Masayoshi Kataoka; Toshiyuki Azuma; Yasuo Ito; Yoneo Tabata; Yasushi Aoki
1988-01-01
Dense helium, whose atomic separation is several Å near 4 K, shows new emission bands following excitation by fast nitrogen ions. These new emissions can be classified into three groups, which grow and disappear stepwise with increasing pressure, accompanied with lifetime shortening except for a group at the highest density. They are explained as clusters of helium excimers.
Bystol, A J; Whitcomb, J L; Campiglia, A D
2001-06-15
A unique method for monitoring polycyclic aromatic hydrocarbons is reported for routine analysis of water samples. The assay consists of a three-step procedure. One hundred milliliters of water is processed through an octadecyl extraction membrane via solid-liquid extraction. The pollutants are eluted with 5 mL of n-hexane and directly determined in the eluting solvent by laser excited time-resolved Shpol'skii spectrometry. Seventy-seven K fluorescence measurements are made with the aid of an optical fiber probe that avoids the complications of classical low-temperature methodology. The total analysis time from the extraction to PAH identification is approximately 5 min per sample. Limits of detection are at the subparts per billion levels. The simplicity of the experimental procedure, the short analysis time, the selectivity, and the excellent analytical figures of merit demonstrate the advantages of this approach for routine analysis of water samples. PMID:11432565
Luttinger surgery along Lagrangian tori and non-isotopy for singular symplectic plane curves
D. Auroux; S. K. Donaldson; L. Katzarkov
2003-01-01
. ?We discuss the properties of a certain type of Dehn surgery along a Lagrangian torus in a symplectic 4-manifold, known as\\u000a Luttinger's surgery, and use this construction to provide a purely topological interpretation of a non-isotopy result for\\u000a symplectic plane curves with cusp and node singularities due to Moishezon [9].
Eichhorn, T R; Haag, M; van den Brandt, B; Hautle, P; Wenckebach, W Th; Jannin, S; van der Klink, J J; Comment, A
2013-09-01
In standard Dynamic Nuclear Polarization (DNP) electron spins are polarized at low temperatures in a strong magnetic field and this polarization is transferred to the nuclear spins by means of a microwave field. To obtain high nuclear polarizations cryogenic equipment reaching temperatures of 1 K or below and superconducting magnets delivering several Tesla are required. This equipment strongly limits applications in nuclear and particle physics where beams of particles interact with the polarized nuclei, as well as in neutron scattering science. The problem can be solved using short-lived optically excited triplet states delivering the electron spin. The spin is polarized in the optical excitation process and both the cryogenic equipment and magnet can be simplified significantly. A versatile apparatus is described that allows to perform pulsed dynamic nuclear polarization experiments at X-band using short-lived optically excited triplet sates. The efficient (4)He flow cryostat that cools the sample to temperatures between 4 K and 300 K has an optical access with a coupling stage for a fiber transporting the light from a dedicated laser system. It is further designed to be operated on a neutron beam. A combined pulse ESR/DNP spectrometer has been developed to observe and characterize the triplet states and to perform pulse DNP experiments. The ESR probe is based on a dielectric ring resonator of 7 mm inner diameter that can accommodate cubic samples of 5mm length needed for neutron experiments. NMR measurements can be performed during DNP with a coil integrated in the cavity. With the presented apparatus a proton polarization of 0.5 has been achieved at 0.3 T. PMID:23838526
Mobile impurities in ferromagnetic liquids
NASA Astrophysics Data System (ADS)
Kantian, Adrian; Schollwoeck, Ulrich; Giamarchi, Thierry
2011-03-01
Recent work has shown that mobile impurities in one dimensional interacting systems may exhibit behaviour that differs strongly from that predicted by standard Tomonaga-Luttinger liquid theory, with the appearance of power-law divergences in the spectral function signifying sublinear diffusion of the impurity. Using time-dependent matrix product states, we investigate a range of cases of mobile impurities in systems beyond the analytically accessible examples to assess the existence of a new universality class of low-energy physics in one-dimensional systems. Correspondence: Adrian.Kantian@unige.ch This work was supported in part by the Swiss SNF under MaNEP and division II.
Phase diagram of the Kohn-Luttinger superconducting state for bilayer graphene
NASA Astrophysics Data System (ADS)
Kagan, Maxim Yu.; Mitskan, Vitaly A.; Korovushkin, Maxim M.
2015-06-01
The effect of Coulomb interaction between Dirac fermions on the formation of the Kohn-Luttinger superconducting state in bilayer doped graphene is studied disregarding of the effect of the van der Waals potential of the substrate and impurities. The phase diagram determining the boundaries of superconductive domains with different types of symmetry of the order parameter is built using the extended Hubbard model in the Born weak-coupling approximation with allowance for the intratomic, interatomic, and interlayer Coulomb interactions between electrons. It is shown that the Kohn-Luttinger polarization contributions up to the second order of perturbation theory in the Coulomb interaction inclusively and an account for the long-range intraplane Coulomb interactions significantly affect the competition between the superconducting phases with the f-, p + ip-, and d + id-wave symmetries of the order parameter. It is demonstrated that the account for the interlayer Coulomb interaction enhances the critical temperature of the transition to the superconducting phase.
The pressure in the Huang-Yang-Luttinger model of an interacting boson gas
M. van den Berg; T. C. Dorlas; J. T. Lewis; J. V. Pulé
1990-01-01
This completes our study of the equilibrium thermodynamics of the Huang-Yang-Luttinger model of a boson gas with a hard-sphere repulsion. In an earlier paper we obtained a lower bound on the pressure, but our proof of an upper bound held only for a truncated version of the model. In this paper we establish an upper bound on the pressure in
Ryabov, E. G.; Nadtochy, P. N.; Adeev, G. D. [Omsk State University, Prospect Mira 55-A, RU-644077, Omsk (Russian Federation); Karpov, A. V. [Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, Dubna RU-141980 (Russian Federation)
2008-10-15
A stochastic approach to fission dynamics based on three-dimensional Langevin equations was applied to calculation of the mass-energy and angular distributions of fission fragments. The dependence of the mass-energy distribution parameters on the angular momentum and the anisotropy of the fission-fragment angular distribution on excitation energy have been studied in a wide range of the fissility parameter. A temperature-dependent finite-range liquid-drop model was used in a consistent way to calculate the functional of the Helmholtz free energy and level-density parameter. The modified one-body mechanism of nuclear dissipation (the so-called surface-plus-window dissipation) was used to determine the dissipative forces in Langevin equations. The evaporation of light prescission particles was taken into account on the basis of a statistical model combined with Langevin dynamics. The calculated parameters of the mass-energy distribution and their angular dependencies are in good quantitative agreement with the available experimental data at the value of the reduction coefficient of the contribution from the wall formula equal to 0.25. Analysis of the anisotropy of the fission-fragment angular distribution performed with the saddle-point transition state model and scission-point transition state model indicates that it is necessary to take into account the dynamical aspects of the fission-fragment angular distribution formation.
Zhai Hui [Center for Advanced Study, Tsinghua University, Beijing (China); Zhou Fei [Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, British Columbia, V6T 1Z1 (Canada)
2005-07-01
We investigate the Zeeman-field-driven quantum phase transitions between singlet spin liquids and algebraically ordered O(2) nematic spin liquids of spin-one bosons in one-dimensional optical lattices. We find that the critical behavior is characterized by condensation of hardcore bosons instead of ideal magnons in high-dimensional lattices. Critical exponents are strongly renormalized by hardcore interactions and critical states are equivalent to the free Fermion model up to the Friedel oscillations. We also find that the algebraically ordered nematic spin liquids close to critical points are fully characterized by the Luttinger-liquid dynamics with Luttinger-liquid parameters magnetically tunable. The Bethe ansatz solution has been applied to determine the critical magnetization and nematic correlations.
Jiang, Zhen; Xu, Ming; Li, Fuyou; Yu, Yanlei
2013-11-01
A red-light-controllable soft actuator has been achieved, driven by low-power excited triplet-triplet annihilation-based upconversion luminescence (TTA-UCL). First, a red-to-blue TTA-based upconversion system with a high absolute quantum yield of 9.3 ± 0.5% was prepared by utilizing platinum(II) tetraphenyltetrabenzoporphyrin (PtTPBP) as the sensitizer and 9,10-bis(diphenylphosphoryl)anthracene (BDPPA) as the annihilator. In order to be employed as a highly effective phototrigger of photodeformable cross-linked liquid-crystal polymers (CLCPs), the PtTPBP&BDPPA system was incorporated into a rubbery polyurethane film and then assembled with an azotolane-containing CLCP film. The generating assembly film bent toward the light source when irradiated with a 635 nm laser at low power density of 200 mW cm(-2) because the TTA-UCL was effectively utilized by the azotolane moieties in the CLCP film, inducing their trans-cis photoisomerization and an alignment change of the mesogens via an emission-reabsorption process. It is the first example of a soft actuator in which the TTA-UCL is trapped and utilized to create photomechanical effect. Such advantages of using this novel red-light-controllable soft actuator in potential biological applications have also been demonstrated as negligible thermal effect and its excellent penetration ability into tissues. This work not only provides a novel photomanipulated soft actuation material system based on the TTA-UCL technology but also introduces a new technological application of the TTA-based upconversion system in photonic devices. PMID:24088066
Adjustable, Broadband, Selective Excitation with Uniform Phase
Kristin E. Cano; Mari A. Smith; A. J. Shaka
2002-01-01
An advance in the problem of achieving broadband, selective, and uniform-phase excitation in NMR spectroscopy of liquids is outlined. Broadband means that, neglecting relaxation, any frequency bandwidth may be excited even when the available radiofrequency (RF) field strength is strictly limited. Selective means that sharp transition edges can be created between pure-phase excitation and no excitation at all. Uniform phase
Spin-resolved entanglement spectroscopy of critical spin chains and Luttinger liquids
Nicolas Laflorencie; Stephan Rachel
2014-11-17
Quantum critical chains are well described and understood by virtue of conformal field theory. Still the meaning of the real space entanglement spectrum -- the eigenvalues of the reduced density matrix -- of such systems remains in general elusive, even when there is an additional quantum number available such as spin or particle number. In this paper we explore in details the properties and the structure of the reduced density matrix of critical XXZ spin-$\\frac{1}{2}$ chains. We investigate the quantum/thermal correspondence between the reduced density matrix of a $T=0$ pure quantum state and the thermal density matrix of an effective entanglement Hamiltonian. Using large scale DMRG and QMC simulations, we investigate the conformal structure of the spectra, the entanglement Hamiltonian and temperature. We then introduce the notion of spin-resolved entanglement entropies which display interesting scaling features.
Superconductivity, spin gaps and Luttinger liquids in a class of cuprates
T. M. Rice; S. Gopalan; M. Sigrist
1993-01-01
A homologous series of cuprates, Srn -1 Cun + 1 O2n, formed by introducing a parallel array of planar defects into the infinite-layer cuprate, SrCuO2, have been reported by Takano et al. In each CuO2 plane line defects consisting of CuO double chains result. An analysis of the electronic properties of such planes demonstrates that the stoichiometric compounds with n
Transport in ropes of carbon nanotubes: Contact barriers and Luttinger liquid theory
Th. Hunger; B. Lengeler; J. Appenzeller
2004-01-01
In this article we report on the conductance of bundles of single-wall carbon nanotubes as a function of temperature and bias voltage. We focus on the nonlinearity in the IV curves near zero bias, i.e., a pronounced conductance dip. While we observe that all temperature dependent data scale onto a single curve, we also find that the characteristic scaling exponent
A unified framework for the Kondo problem and for an impurity in a Luttinger liquid
P. Fendley; F. Lesage; H. Saleur
1996-01-01
We develop a unified theoretical framework for the anisotropic Kondo model and the boundary sine-Gordon model. They are both boundary integrable quantum field theories with a quantum-group spin at the boundary which takes values, respectively, in standard or cyclic representations of the quantum groupSU(2)q. This unification is powerful, and allows us to find new results for both models. For the
Kondo effect in a Luttinger liquid: Nonuniversality of the Wilson ratio
NASA Astrophysics Data System (ADS)
Le Hur, Karyn
1999-05-01
Using a coset Ising-Bose representation, we show how backscattering of electrons off a magnetic impurity destabilizes the two-channel Kondo fixed point and drives the system to a new fixed point, in agreement with previous results [P. Fröjdh and H. Johannesson, Phys. Rev. Lett. 75, 300 (1995)]. In addition, we find that the presence of several leading correction-to-boundary operators in the spinon basis, for nonzero U, implies a not well-defined Wilson ratio. Finally, we show that a strong potential scattering at the impurity site stabilizes the two-channel Kondo fixed point in the neighborhood of half-filling.
Phenomenology of one-dimensional quantum liquids beyond the low-energy limit.
Imambekov, Adilet; Glazman, Leonid I
2009-03-27
We consider the zero temperature behavior of dynamic response functions of 1D systems near edges of support in the momentum-energy plane (k,omega). The description of the singularities of dynamic response functions near an edge epsilon(k) is given by the effective Hamiltonian of a mobile impurity moving in a Luttinger liquid. For Galilean-invariant systems, we relate the parameters of such an effective Hamiltonian to the properties of the function epsilon(k). This allows us to express the exponents which characterize singular response functions of spinless bosonic or fermionic liquids in terms of epsilon(k) and Luttinger liquid parameters for any k. For an antiferromagnetic Heisenberg spin-1/2 chain in a zero magnetic field, SU(2) invariance fixes the exponents from purely phenomenological considerations. PMID:19392303
Violation of Luttinger's Theorem in the Two-Dimensional t- J Model
NASA Astrophysics Data System (ADS)
Putikka, W. O.; Luchini, M. U.; Singh, R. R. P.
1998-10-01
We have calculated the high temperature series for the momentum distribution function nk of the 2D t-J model to twelfth order in inverse temperature. By extrapolating the series to T = 0.2J we searched for a Fermi surface of the 2D t-J model. We find that three criteria used for estimating the location of a Fermi surface violate Luttinger's theorem, implying that the t-J model does not have an adiabatic connection to a noninteracting model.
Luttinger model approach to interacting one-dimensional fermions in a harmonic trap
W. Wonneberger
2001-03-08
A model of interacting one--dimensional fermions confined to a harmonic trap is proposed. The model is treated analytically to all orders of the coupling constant by a method analogous to that used for the Luttinger model. As a first application, the particle density is evaluated and the behavior of Friedel oscillations under the influence of interactions is studied. It is found that attractive interactions tend to suppress the Friedel oscillations while strong repulsive interactions enhance the Friedel oscillations significantly. The momentum distribution function and the relation of the model interaction to realistic pair interactions are also discussed.
NASA Astrophysics Data System (ADS)
Suemasa, Riki; Fuseya, Yuki
2015-04-01
The effective g-factor and the selection rules for the matrix elements of the velocity operator are investigated for the Luttinger Hamiltonian under a magnetic field. It is shown that the g-factor has a strong kz-dependence, where kz is the wave vector along the magnetic field. This anomalous kz-dependence is due to the interband effect of the magnetic field between the light and heavy hole bands. It is found that a nontrivial contribution to the longitudinal magnetoconductivity arises also due to the interband effects by analyzing the selection rules. This nontrivial interband contribution can be a source of the longitudinal spin current.
Renormalization group and the Fermi surface in the Luttinger model. G. Benfatto 1 , G. Gallavotti 2 is independent of L up to terms of order 1=L), and fi 0 is the velocity at the Fermi surface; â??v of view of the renormalization group. A perturbation theory of the beta function of the model is derived
NASA Astrophysics Data System (ADS)
Busche, Tom; Kopietz, Peter
We calculate the effect of a quadratic term in the energy dispersion on the low-energy behavior of the Green's function of the spinless Tomonaga-Luttinger model (TLM). Assuming that for small wave-vectors q=k-kF the fermionic excitation energy relative to the Fermi energy is vFq+q2/(2m), we explicitly calculate the single-particle Green's function for finite but small values of ?=qc/(2kF). Here kF is the Fermi wave-vector, qc is the maximal momentum transfered by the interaction, and vF=kF/m is the Fermi velocity. Assuming equal forward scattering couplings g2=g4, we find that the dominant effect of the quadratic term in the energy dispersion is a renormalization of the anomalous dimension. In particular, at weak coupling the anomalous dimension is ~ {? }=? (1-2? 2? ), where ? is the anomalous dimension of the TLM. We also show how to treat the change of the chemical potential due to the interactions within the functional bosonization approach in arbitrary dimensions.
Phase theory and critical exponents for the Tomonaga-Luttinger model with harmonic confinement
Gao Xianlong; W. Wonneberger
2004-06-02
A phase operator formulation for a recent model of interacting one-dimensional fermions in a harmonic trap is developed. The resulting theory is similar to the corresponding approach for the Luttinger model with open boundary conditions (OBC). However, in place of the spatial coordinate $z$, a dimensionless variable $u$ defined on the unit circle appears as argument of the phase fields and $u$ is non-linearly related to $z$. Furthermore, form factors appear which reflect the harmonic trap geometry. The theory is applied to calculate one-particle correlation functions. In a properly defined thermodynamic limit, bulk and boundary critical exponents are calculated for the static two-point correlation function and the dynamic local correlation function. The local spectral density is also considered. The critical exponents found are in agreement with those known for OBC with the exception of the boundary scaling exponent $\\Delta_\\perp$.
Multiband Hamiltonians of the Luttinger-Kohn Theory and Ellipticity Requirements
Dmytro Sytnyk; Sunil Patil; Roderick Melnik
2010-04-14
Modern applications require a robust and theoretically strong tool for the realistic modeling of electronic states in low dimensional nanostructures. The $k \\cdot p$ theory has fruitfully served this role for the long time since its creation. During last two decades several problems have been detected in connection with the application of the $k \\cdot p$ approach to such nanostructures. These problems are closely related to the violation of the ellipticity conditions for the underlying system, the fact that until recently has been largely overlooked. We demonstrate that in many cases the models derived by a formal application of the Luttinger-Kohn theory fail to satisfy the ellipticity requirements. The detailed analysis, presented here on an example of the $6 \\times 6$ Hamiltonians, shows that this failure has a strong impact on the physically important properties conventionally studied with these models.
N. C. Pyper; D. W. Essex; Colm T. Whelan
2001-01-01
The energy of the He 1s ? 1s2p(P) transition for helium atoms in liquid helium, solid helium and helium bubbles in metals is greater than for free helium atoms by an amount known as the energy shift. The energy shift is calculated by combining the results of ab-initio self-consistent field electronic structure calculations with corrections to account for the effects
Stimulated Raman scattering imaging by continuous-wave laser excitation
Cheng, Ji-Xin
microscopy [8]. By cw laser excitation, SRS spectroscopy of liquid benzene was shown in 1977 [9]. Recently]. In this work, SRS imaging of biologi- cal tissue by using cw lasers as excitation sources is demonstrated
Lopez-Aguilar, F.; Costa-Quintana, J. (Dept. de Fisica, Grupo de Electromagnetismo, Univ. Autonoma de Barcelona, Bellaterra, E-08193 Barcelona (ES))
1992-07-10
In this paper, the authors give a method for obtaining the renormalized electronic structure of the Hubbard systems. The first step is the determination of the self-energy beyond the Hartree-Fock approximation. This self-energy is constructed from several dielectric response functions. The second step is the determination of the quasiparticle band structure calculation which is performed from an appropriate modification of the augmented plane wave method. The third step consists in the determination of the renormalized density of states deduced from the spectral functions. The analysis of the renormalized density of states of the strongly correlated systems leads to the conclusion that there exist three types of resonances in their electronic structures, the lower energy resonances (LER), the middle energy resonances (MER) and the upper energy resonances (UER). In addition, the authors analyze the conditions for which the Luttinger theorem is satisfied. All of these questions are determined in a characteristic example which allows to test the theoretical method.
Hydrodynamic pressure in liquid filled container
NASA Astrophysics Data System (ADS)
Maiti, Pabitra Ranjan
2011-12-01
Liquid storage tanks are used to store oil, drinking water and different liquids which are necessary in industry and energy production. Partially liquid filled container shows free surface movement under external excitation this phenomenon is known as sloshing of liquid. When external excitation frequency matches the natural frequency of sloshing, a violent oscillation may occur that causes excess dynamic pressure on the tank structure. The dynamic behavior of liquid storage tanks under seismic excitation has been the subject of numerous theoretical and experimental investigations. This paper presents a pressure based finite element analysis of the liquid-structure systems considering the coupled effect of elastic structure and liquid. The equation of motion of the liquid is considered as incompressible and inviscid. The hydrodynamic pressure variation along a wall of prismatic container is studied and presented for different fill depth of liquid under sinusoidal base excitation.
Magnetostrictive resonance excitation
Schwarz, Ricardo B. (Los Alamos, NM); Kuokkala, Veli-Tapani (Tampere, FI)
1992-01-01
The resonance frequency spectrum of a magnetostrictive sample is remotely determined by exciting the magnetostrictive property with an oscillating magnetic field. The permeability of a magnetostrictive material and concomitant coupling with a detection coil varies with the strain in the material whereby resonance responses of the sample can be readily detected. A suitable sample may be a magnetostrictive material or some other material having at least one side coated with a magnetostrictive material. When the sample is a suitable shape, i.e., a cube, rectangular parallelepiped, solid sphere or spherical shell, the elastic moduli or the material can be analytically determined from the measured resonance frequency spectrum. No mechanical transducers are required and the sample excitation is obtained without contact with the sample, leading to highly reproducible results and a measurement capability over a wide temperature range, e.g. from liquid nitrogen temperature to the Curie temperature of the magnetostrictive material.
Quasiparticles and Fermi liquid behaviour in an organic metal
NASA Astrophysics Data System (ADS)
Kiss, T.; Chainani, A.; Yamamoto, H. M.; Miyazaki, T.; Akimoto, T.; Shimojima, T.; Ishizaka, K.; Watanabe, S.; Chen, C.-T.; Fukaya, A.; Kato, R.; Shin, S.
2012-09-01
Many organic metals display exotic properties such as superconductivity, spin-charge separation and so on and have been described as quasi-one-dimensional Luttinger liquids. However, a genuine Fermi liquid behaviour with quasiparticles and Fermi surfaces have not been reported to date for any organic metal. Here, we report the experimental Fermi surface and band structure of an organic metal (BEDT-TTF)3Br(pBIB) obtained using angle-resolved photoelectron spectroscopy, and show its consistency with first-principles band structure calculations. Our results reveal a quasiparticle renormalization at low energy scales (effective mass m*=1.9?me) and ?2 dependence of the imaginary part of the self energy, limited by a kink at ~50?meV arising from coupling to molecular vibrations. The study unambiguously proves that (BEDT-TTF)3Br(pBIB) is a quasi-2D organic Fermi liquid with a Fermi surface consistent with Shubnikov-de Haas results.
Kagan, M. Yu., E-mail: kagan@kapitza.ras.ru [Russian Academy of Sciences, Kapitza Institute for Physical Problems (Russian Federation); Val'kov, V. V.; Mitskan, V. A.; Korovuskin, M. M. [Russian Academy of Sciences, Kirenskii Physics Institute, Siberian Branch (Russian Federation)] [Russian Academy of Sciences, Kirenskii Physics Institute, Siberian Branch (Russian Federation)
2013-10-15
Using the Shubin-Vonsovsky model in the weak-coupling regime W > U > V (W is the bandwidth, U is the Hubbard onsite repulsion, and V is the Coulomb interaction at neighboring sites) based on the Kohn-Luttinger mechanism, we determined the regions of the existence of the superconducting phases with the d{sub xy}, p, s, and d{sub x{sup 2}-y{sup 2}} symmetry types of the order parameter. It is shown that the effective interaction in the Cooper channel considerably depends not only on single-site but also on intersite Coulomb correlations. This is demonstrated by the example of the qualitative change and complication of the phase diagram of the superconducting state. The superconducting (SC) phase induction mechanism is determined taking into account polarization contributions in the second-order perturbation theory in the Coulomb interaction. The results obtained for the angular dependence of the superconducting gap in different channels are compared with angule-resolved photoemission spectroscopy (ARPES) results. The influence of long-range hops in the phase diagram and critical superconducting transition temperature in different channels is analyzed. The conditions for the appearance of the Kohn-Luttinger superconductivity with the d{sub x{sup 2}-y{sup 2}} symmetry and high critical temperatures T{sub c} {approx} 100 K near the half-filling are determined.
Takeuchi, Asia; Ahern, Terence L.; Henderson, Sean O.
2011-01-01
Excited (or agitated) delirium is characterized by agitation, aggression, acute distress and sudden death, often in the pre-hospital care setting. It is typically associated with the use of drugs that alter dopamine processing, hyperthermia, and, most notably, sometimes with death of the affected person in the custody of law enforcement. Subjects typically die from cardiopulmonary arrest, although the cause is debated. Unfortunately an adequate treatment plan has yet to be established, in part due to the fact that most patients die before hospital arrival. While there is still much to be discovered about the pathophysiology and treatment, it is hoped that this extensive review will provide both police and medical personnel with the information necessary to recognize and respond appropriately to excited delirium. PMID:21691475
Self-trapped excitations in condensed matter physics
M. Heritier; P. Lederer; G. Montambaux
1980-01-01
The authors discuss a general formulation for self-trapped excitations in condensed matter physics. Previously known aspects include lattice polarons, spin polarons, bubblons, etc. New aspects involve collective excitation self-trapping; solidons in liquid He have been suggested as the correct description for rotons. They emphasise the difference of self-trapped excitations with order parameter fluctuations.
A. Schwartz; M. Dressel; G. Grüner; V. Vescoli; L. Degiorgi; T. Giamarchi
1998-01-01
We have measured the electrodynamic response in the metallic state of three highly anisotropic conductors, (TMTSF)2X, where X=PF6, AsF6, or ClO4, and TMTSF is the organic molecule tetramethyltetraselenofulvalene. In all three cases we find dramatic deviations from a simple Drude response. The optical conductivity has two features: a narrow mode at zero frequency, with a small spectral weight, and a
Sloshing motions in excited tanks
Jannette B. Frandsen
2004-01-01
A fully non-linear finite difference model has been developed based on inviscid flow equations. Numerical experiments of sloshing wave motion are undertaken in a 2-D tank which is moved both horizontally and vertically. Results of liquid sloshing induced by harmonic base excitations are presented for small to steep non-breaking waves. The simulations are limited to a single water depth above
Deconfined fractionally charged excitation in any dimensions
Chern, Chyh-Hong, E-mail: chchern@ntu.edu.tw; Huang, Po-Hao; Lee, Hong-Hsi
2013-05-15
An exact incompressible quantum liquid is constructed at the filling factor 1/m{sup 2} in the square lattice. It supports deconfined fractionally charged excitation. At the filling factor 1/m{sup 2}, the excitation has fractional charge e/m{sup 2}, where e is the electric charge. This model can be easily generalized to the n-dimensional square lattice (integer lattice), where the charge of excitations becomes e/m{sup n}. -- Highlights: ? We demonstrate that the fractionally-charged excitations can in principle exist in any dimensions. ? We compute the fractional charge of the excitations (e{sup ?}=e/m{sup D}). ? We demonstrate that the fractionally-charged excitation is in a deconfined phase.
Particle Beam Excitation Electron Beam Excitation
Schroder, Dieter K.
Microprobe Microanalysis (EMP) Transmission Electron Microscopy (TEM) Scanning Auger Microscopy (SAMParticle Beam Excitation Electron Beam Excitation Scanning Electron Microscopy (SEM) Electron Projector lens Electron multiplier Fluorescent screen X-Y stage Microchannel plate Immersion lens Measures m
Elementary excitations of sup 4 He clusters
Casas, M. (Universitat de les Illes Balears, Palma de Mallorca (Spain)); Stringari, S. (Universita di Trento, Povo (Italy))
1990-05-01
The elementary excitations of {sup 4}He clusters containing N atoms are investigated by solving the equations of the random phase approximation (RPA) with a phenomenological effective interaction. The calculations were done for 40{le}N{le}728. The effects of the RPA correlations are explicitly discussed. Important deviations from the predictions of the liquid droplet model (LDM) are found up to N{approx equal}500 for the breathing compression mode and up to N{approx equal}100 for surface excitations. Sum rules for compression and surface excitations are also derived and discussed.
Universal nature of collective plasmonic excitations in finite 1-D carbon-based nanostructures
Polizzi, Eric
2015-01-01
Tomonaga-Luttinger (T-L) theory predicts collective plasmon resonances in 1-D nanostructure conductors of finite length, that vary roughly in inverse proportion to the length of the structure. Yet, such resonances have not been clearly identified in experiments so far. Here we provide evidence of the T-L plasmon resonances using first-principle computational real-time spectroscopy studies of representative finite 1-D carbon-based nanostructures ranging from atom and benzene-like chain structures to short carbon nanotubes. Our all-electron Time-Dependent Density-Functional Theory (TDDFT) real-time simulation framework is capable to accurately capture the relevant nanoscopic effects including correct frequencies for known optical transitions, and various collective plasmon excitations. The presence of 1-D T-L plasmons is universally predicted by the various numerical experiments, which also demonstrate a phenomenon of resonance splitting. Extending these simulations to longer structures will allow the accurate ...
Liquid Nitrogen Ice Cream (1st Grade) Lesson Plan
Liquid Nitrogen Ice Cream (1st Grade) Lesson Plan Science Standards Addressed (From the Colorado substance. Materials: 5 or more Liters of liquid nitrogen (gloves, goggles, and lab coat recommended. Introduce kids to liquid nitrogen. Explain that it is a liquid and is very cold (kids will be excited
NASA Astrophysics Data System (ADS)
Kozik, Evgeny; Ferrero, Michel; Georges, Antoine
2015-04-01
The Luttinger-Ward functional ? [G ] , which expresses the thermodynamic grand potential in terms of the interacting single-particle Green's function G , is found to be ill defined for fermionic models with the Hubbard on-site interaction. In particular, we show that the self-energy ? [G ]?? ? [G ]/? G is not a single-valued functional of G : in addition to the physical solution for ? [G ] , there exists at least one qualitatively distinct unphysical branch. This result is demonstrated for several models: the Hubbard atom, the Anderson impurity model, and the full two-dimensional Hubbard model. Despite this pathology, the skeleton Feynman diagrammatic series for ? in terms of G is found to converge at least for moderately low temperatures. However, at strong interactions, its convergence is to the unphysical branch. This reveals a new scenario of breaking down of diagrammatic expansions. In contrast, the bare series in terms of the noninteracting Green's function G0 converges to the correct physical branch of ? in all cases currently accessible by diagrammatic Monte Carlo calculations. In addition to their conceptual importance, these observations have important implications for techniques based on the explicit summation of the diagrammatic series.
A Novel Liquid-Liquid Transition in Undercooled Ti-Zr-Ni Liquids
NASA Technical Reports Server (NTRS)
Lee, G. W.; Gangopadhyay, A. K.; Kelton, K. F.; Bradshaw, R. C.; Hyers, R. W.; Rathz, T. J.; Rogers, J. R.
2004-01-01
If crystallization can be avoided, liquids enter a metastable (undercooled) state below their equilibrium liquidus temperatures, T(sub l), finally 'freezing' into a glass below a characteristic temperature called the glass transition temperature, T(sub g). In rare cases, the undercooled liquid may undergo a liquid-liquid phase transition (liquid polymorphism) before entering the glassy state. This has been suggested from experimental studies of H2O and Si. Such phase transitions have been predicted in some stable liquids, ie. above T(sub l) at atmospheric pressure, for SiO2 and BeF2, but these have not been verified experimentally. They have been observed in liquids of P, Si and C, but only under high pressure. In this letter we present the first experimental evidence for a phase transition in a low viscosity metallic liquid that is driven by an approach to a constant entropy configuration state and correlated with a growing icosahedral order in the liquid. A maximum in the specific heat at constant pressure, similar to what is normally observed near T(sub g), is reported for undercooled liquids of quasicrystal-forming Ti-Zr-Ni alloys. A two-state excitation model that includes cooperativity by incorporating a temperature-dependent excitation energy, fits the specific heat data well, signaling a phase transition. An inflection in the liquid density with decreasing temperature instead of a discontinuity indicates that this is not a typical first order phase transition; it could be a weakly first order or higher order transition. While showing many similarities to a glass transition, this liquid-liquid phase transition occurs in a mobile liquid, making it novel.
Anisotropic Fermi surfaces and Kohn-Luttinger superconductivity in two dimensions
Gonzalez, J.; Guinea, F.; Vozmediano, M.A.H.
1999-08-10
The instabilities induced on a two-dimensional system of correlated electrons by the anisotropies of its Fermi line are analyzed on general grounds. Simple scaling arguments allow to predict the opening of a superconducting gap with a well-defined symmetry prescribed by the geometry of the Fermi line. The same arguments predict a critical dimension of 3/2 for the transition of the two-dimensional system to non-Fermi liquid behavior. The methods are applied to the t-t{prime} Hubbard model in a wide range of dopings.
Anisotropic Fermi Surfaces and Kohn-Luttinger Superconductivity in Two Dimensions
NASA Astrophysics Data System (ADS)
González, J.; Guinea, F.; Vozmediano, M. A. H.
The instabilities induced on a two-dimensional system of correlated electrons by the anisotropies of its Fermi line are analyzed on general grounds. Simple scaling arguments allow to predict the opening of a superconducting gap with a well-defined symmetry prescribed by the geometry of the Fermi line. The same arguments predict a critical dimension of 3/2 for the transition of the two-dimensional system to non-Fermi liquid behavior. The methods are applied to the t-t? Hubbard model in a wide range of dopings.
Faraday Waves under Time-Reversed Excitation
NASA Astrophysics Data System (ADS)
Pietschmann, Dirk; Stannarius, Ralf; Wagner, Christian; John, Thomas
2013-03-01
Do parametrically driven systems distinguish periodic excitations that are time mirrors of each other? Faraday waves in a Newtonian fluid are studied under excitation with superimposed harmonic wave forms. We demonstrate that the threshold parameters for the stability of the ground state are insensitive to a time inversion of the driving function. This is a peculiarity of some dynamic systems. The Faraday system shares this property with standard electroconvection in nematic liquid crystals [J. Heuer , Phys. Rev. E 78, 036218 (2008)PLEEE81539-3755]. In general, time inversion of the excitation affects the asymptotic stability of a parametrically driven system, even when it is described by linear ordinary differential equations. Obviously, the observed symmetry has to be attributed to the particular structure of the underlying differential equation system. The pattern selection of the Faraday waves above threshold, on the other hand, discriminates between time-mirrored excitation functions.
Spin liquids : mean field and beyond
Serbyn, Maksym
2014-01-01
Spin liquids are fluid-like ground states of spin systems, where spins do not order at zero temperature. These states have long-range entanglement and concomitant exotic properties, such as fractionalized excitations and ...
Acoustically excited heated jets. 1: Internal excitation
NASA Technical Reports Server (NTRS)
Lepicovsky, J.; Ahuja, K. K.; Brown, W. H.; Salikuddin, M.; Morris, P. J.
1988-01-01
The effects of relatively strong upstream acoustic excitation on the mixing of heated jets with the surrounding air are investigated. To determine the extent of the available information on experiments and theories dealing with acoustically excited heated jets, an extensive literature survey was carried out. The experimental program consisted of flow visualization and flowfield velocity and temperature measurements for a broad range of jet operating and flow excitation conditions. A 50.8-mm-diam nozzle was used for this purpose. Parallel to the experimental study, an existing theoretical model of excited jets was refined to include the region downstream of the jet potential core. Excellent agreement was found between theory and experiment in moderately heated jets. However, the theory has not yet been confirmed for highly heated jets. It was found that the sensitivity of heated jets to upstream acoustic excitation varies strongly with the jet operating conditions and that the threshold excitation level increases with increasing jet temperature. Furthermore, the preferential Strouhal number is found not to change significantly with a change of the jet operating conditions. Finally, the effects of the nozzle exit boundary layer thickness appear to be similar for both heated and unheated jets at low Mach numbers.
Elephant's foot phenomenon in liquid storage tanks
1983-01-01
This paper presents a method for analyzing the seismic response of a flat bottomed cylindrical liquid storage tank to vertical earthquake excitation. Here, vertical earthquake acceleration is considered to correspond to an increase in the density of a stored liquid. Taking into account the vertical and horizontal earthquake loads, hydrostatic pressure, and considering restrictive moment and shear forces at shell-bottom
Non-Fermi-liquid and topological states with strong spin-orbit coupling.
Moon, Eun-Gook; Xu, Cenke; Kim, Yong Baek; Balents, Leon
2013-11-15
We argue that a class of strongly spin-orbit-coupled materials, including some pyrochlore iridates and the inverted band gap semiconductor HgTe, may be described by a minimal model consisting of the Luttinger Hamiltonian supplemented by Coulomb interactions, a problem studied by Abrikosov and collaborators. It contains twofold degenerate conduction and valence bands touching quadratically at the zone center. Using modern renormalization group methods, we update and extend Abrikosov's classic work and show that interactions induce a quantum critical non-Fermi-liquid phase, stable provided time-reversal and cubic symmetries are maintained. We determine the universal power-law exponents describing various observables in this Luttinger-Abrikosov-Beneslavskii state, which include conductivity, specific heat, nonlinear susceptibility, and the magnetic Gruneisen number. Furthermore, we determine the phase diagram in the presence of cubic and/or time-reversal symmetry breaking perturbations, which includes a topological insulator and Weyl semimetal phases. Many of these phases possess an extraordinarily large anomalous Hall effect, with the Hall conductivity scaling sublinearly with magnetization ?(xy)?M0.51. PMID:24289698
Adjustable, Broadband, Selective Excitation with Uniform Phase
NASA Astrophysics Data System (ADS)
Cano, Kristin E.; Smith, Mari A.; Shaka, A. J.
2002-03-01
An advance in the problem of achieving broadband, selective, and uniform-phase excitation in NMR spectroscopy of liquids is outlined. Broadband means that, neglecting relaxation, any frequency bandwidth may be excited even when the available radiofrequency (RF) field strength is strictly limited. Selective means that sharp transition edges can be created between pure-phase excitation and no excitation at all. Uniform phase means that, neglecting spin-spin coupling, all resonance lines have nearly the same phase. Conventional uniform-phase excitation pulses (e.g., E-BURP), mostly based on amplitude modulation of the RF field, are not broadband: they have an achievable bandwidth that is strictly limited by the peak power available. Other compensated pulses based on adiabatic half-passage, like BIR-4, are not selective. By contrast, inversion pulses based on adiabatic fast passage can be broadband (and selective) in the sense above. The advance outlined is a way to reformulate these frequency modulated (FM) pulses for excitation, rather than just inversion.
Adjustable, broadband, selective excitation with uniform phase.
Cano, Kristin E; Smith, Mari A; Shaka, A J
2002-03-01
An advance in the problem of achieving broadband, selective, and uniform-phase excitation in NMR spectroscopy of liquids is outlined. Broadband means that, neglecting relaxation, any frequency bandwidth may be excited even when the available radiofrequency (RF) field strength is strictly limited. Selective means that sharp transition edges can be created between pure-phase excitation and no excitation at all. Uniform phase means that, neglecting spin-spin coupling, all resonance lines have nearly the same phase. Conventional uniform-phase excitation pulses (e.g., E-BURP), mostly based on amplitude modulation of the RF field, are not broadband: they have an achievable bandwidth that is strictly limited by the peak power available. Other compensated pulses based on adiabatic half-passage, like BIR-4, are not selective. By contrast, inversion pulses based on adiabatic fast passage can be broadband (and selective) in the sense above. The advance outlined is a way to reformulate these frequency modulated (FM) pulses for excitation, rather than just inversion. PMID:11945042
A new Diffractometer for Studies of Liquid—Liquid Interfaces
NASA Astrophysics Data System (ADS)
Murphy, B. M.; Greve, M.; Runge, B.; Koops, C. T.; Elsen, A.; Stettner, J.; Seeck, O. H.; Magnussen, O. M.
2010-06-01
We have designed a novel, dedicated diffractometer for surface x-ray scattering studies of liquid—liquid and liquid-gas interfaces for the PETRA III High Resolution Diffraction Beamline. Using a double crystal beam-tilter in Bragg geometry this new instrument enables reflectivity and grazing incidence diffraction investigations without moving the sample, which is mechanically decoupled from the rest of the diffractometer. This design minimizes external excitation of surface vibrations, a key prerequisite for studies of liquid interfaces. The instrument operates over the energy range 6.4 keV to 30 keV, the higher energy range being optimal for penetration through liquid sample environments. Vertical momentum transfer up to qz = 2.5 Å-1 and lateral q? up to 4 Å-1will be available.
BROADBAND EXCITATION IN NUCLEAR MAGNETIC RESONANCE
Tycko, R.
1984-10-01
Theoretical methods for designing sequences of radio frequency (rf) radiation pulses for broadband excitation of spin systems in nuclear magnetic resonance (NMR) are described. The sequences excite spins uniformly over large ranges of resonant frequencies arising from static magnetic field inhomogeneity, chemical shift differences, or spin couplings, or over large ranges of rf field amplitudes. Specific sequences for creating a population inversion or transverse magnetization are derived and demonstrated experimentally in liquid and solid state NMR. One approach to broadband excitation is based on principles of coherent averaging theory. A general formalism for deriving pulse sequences is given, along with computational methods for specific cases. This approach leads to sequences that produce strictly constant transformations of a spin system. The importance of this feature in NMR applications is discussed. A second approach to broadband excitation makes use of iterative schemes, i.e. sets of operations that are applied repetitively to a given initial pulse sequences, generating a series of increasingly complex sequences with increasingly desirable properties. A general mathematical framework for analyzing iterative schemes is developed. An iterative scheme is treated as a function that acts on a space of operators corresponding to the transformations produced by all possible pulse sequences. The fixed points of the function and the stability of the fixed points are shown to determine the essential behavior of the scheme. Iterative schemes for broadband population inversion are treated in detail. Algebraic and numerical methods for performing the mathematical analysis are presented. Two additional topics are treated. The first is the construction of sequences for uniform excitation of double-quantum coherence and for uniform polarization transfer over a range of spin couplings. Double-quantum excitation sequences are demonstrated in a liquid crystal system. The second additional topic is the construction of iterative schemes for narrowband population inversion. The use of sequences that invert spin populations only over a narrow range of rf field amplitudes to spatially localize NMR signals in an rf field gradient is discussed.
Quasiparticles and Fermi liquid behaviour in an organic metal
Kiss, T.; Chainani, A.; Yamamoto, H.M.; Miyazaki, T.; Akimoto, T.; Shimojima, T.; Ishizaka, K.; Watanabe, S.; Chen, C.-T.; Fukaya, A.; Kato, R.; Shin, S.
2012-01-01
Many organic metals display exotic properties such as superconductivity, spin-charge separation and so on and have been described as quasi-one-dimensional Luttinger liquids. However, a genuine Fermi liquid behaviour with quasiparticles and Fermi surfaces have not been reported to date for any organic metal. Here, we report the experimental Fermi surface and band structure of an organic metal (BEDT-TTF)3Br(pBIB) obtained using angle-resolved photoelectron spectroscopy, and show its consistency with first-principles band structure calculations. Our results reveal a quasiparticle renormalization at low energy scales (effective mass m*=1.9?me) and ?2 dependence of the imaginary part of the self energy, limited by a kink at ~50?meV arising from coupling to molecular vibrations. The study unambiguously proves that (BEDT-TTF)3Br(pBIB) is a quasi-2D organic Fermi liquid with a Fermi surface consistent with Shubnikov-de Haas results. PMID:23011143
Bosonization and fermion liquids in dimensions greater than one
NASA Astrophysics Data System (ADS)
Houghton, A.; Marston, J. B.
1993-09-01
We develop and describe new approaches to the problem of interacting fermions in spatial dimensions greater than 1. These approaches are based on generalizations of powerful tools previously applied to problems in one spatial dimension. We begin with a review of one-dimensional interacting fermions. We then introduce a simplified model in two spatial dimensions to study the role that spin and perfect nesting play in destabilizing fermion liquids. The complicated functional renormalization-group equations of the full problem are made tractable in our model by replacing the continuum of points that make up the closed Fermi line with four Fermi points. Despite this drastic approximation, the model exhibits physically reasonable behavior both at half-filling (where instabilities occur) and away from half-filling (where a Luttinger liquid arises). Next we implement the bosonization of higher-dimensional Fermi surfaces introduced by Luther and advocated most recently by Haldane. Bosonization incorporates the phase-space and small-angle scattering processes neglected in our model (but does not, as yet, address questions of stability). The charge sector is equivalent to an exactly solvable Gaussian quantum field theory; the spin sector, however, must be solved semiclassically. Using the Luther-Haldane approach we recover the collective mode equation of Fermi-liquid theory and in three dimensions reproduce the T3ln(T) contribution to the specific heat due to small-angle scattering processes. We conclude with a discussion of our results and some speculation about future possibilities.
Quasiparticles and Fermi liquid behaviour in an organic metal.
Kiss, T; Chainani, A; Yamamoto, H M; Miyazaki, T; Akimoto, T; Shimojima, T; Ishizaka, K; Watanabe, S; Chen, C-T; Fukaya, A; Kato, R; Shin, S
2012-01-01
Many organic metals display exotic properties such as superconductivity, spin-charge separation and so on and have been described as quasi-one-dimensional Luttinger liquids. However, a genuine Fermi liquid behaviour with quasiparticles and Fermi surfaces have not been reported to date for any organic metal. Here, we report the experimental Fermi surface and band structure of an organic metal (BEDT-TTF)(3)Br(pBIB) obtained using angle-resolved photoelectron spectroscopy, and show its consistency with first-principles band structure calculations. Our results reveal a quasiparticle renormalization at low energy scales (effective mass m*=1.9?m(e)) and ?(2) dependence of the imaginary part of the self energy, limited by a kink at ~50?meV arising from coupling to molecular vibrations. The study unambiguously proves that (BEDT-TTF)(3)Br(pBIB) is a quasi-2D organic Fermi liquid with a Fermi surface consistent with Shubnikov-de Haas results. PMID:23011143
Collective excitations on a surface of topological insulator
2012-01-01
We study collective excitations in a helical electron liquid on a surface of three-dimensional topological insulator. Electron in helical liquid obeys Dirac-like equation for massless particles and direction of its spin is strictly determined by its momentum. Due to this spin-momentum locking, collective excitations in the system manifest themselves as coupled charge- and spin-density waves. We develop quantum field-theoretical description of spin-plasmons in helical liquid and study their properties and internal structure. Value of spin polarization arising in the system with excited spin-plasmons is calculated. We also consider the scattering of spin-plasmons on magnetic and nonmagnetic impurities and external potentials, and show that the scattering occurs mainly into two side lobes. Analogies with Dirac electron gas in graphene are discussed. PACS: 73.20.Mf; 73.22.Lp; 75.25.Dk. PMID:22376744
Exciting Effects of Excited 0+ Energies
McCutchan, E.A.; Zamfir, N.V.; Casten, R.F. [Wright Nuclear Structure Laboratory, Yale University, New Haven, CT 06520 (United States)
2004-09-13
The significance of considering excited 0+ states is discussed in both an experimental and theoretical context. Experimental results on possible phase transitional nuclei are presented. New calculations on Yb and Hf nuclei in the framework of the IBA-1 model are presented and compared to previous fits in this region.
Non-Fermi Liquid Photoemission Line Shapes in Quasi-One-Dimensional Mo Bronzes
NASA Astrophysics Data System (ADS)
Gweon, Gey-Hong
2001-03-01
Quasi-one-dimensional (quasi-1d) ``K blue bronze'' K_0.3MoO3 and ``Li purple bronze'' Li_0.9Mo_6O_17 both show non-Fermi liquid angle resolved photoemission (ARPES) line shapes in their metallic phases [1,2]. The former has a charge density wave (CDW) transition at T_CDW=180 K, and the latter a transition of an unknown origin at T_X=24 K without any electronic gap opening across T_X. We show that the non-CDW Li purple bronze is so far a unique example where normal state ARPES line shapes can be meaningfully and favorably compared with a purely Luttinger liquid line shape. We show that the PES line shapes for the K blue bronze are not easily understood within a fluctuation-induced CDW pseudo-gap model, implying the need to include electron correlations. Detailed T-dependent ARPES data show little peak movement but only an intensity redistribution across T_CDW, reminiscent of recent quasi-1d theory for dimensional cross-over in a superconducting transition [3]. While neither material is fully described by present line shape theories, we argue that the Li purple and the K blue bronzes can be characterized, respectively, as Tomonaga-Luttinger and Luther-Emery liquids, the latter consistent with an early suggestion of Voit [4]. [1] G.-H. Gweon et al, J. Phys.-Condens. Matter 8, 9923 (1996). [2] J.D. Denlinger et al, Phys. Rev. Lett. 82, 2540 (1999); G.-H. Gweon et al, Phys. Rev. Lett. 85, 3985 (2000). [3] E.W. Carlson et al, Phys. Rev. B 62, 3422 (2000). [4] J. Voit, J. Phys.-Condens. Matter 5, 8305 (1993).
A Liquid-Liquid Transition in an Undercooled Ti-Zr-Ni Liquid
NASA Technical Reports Server (NTRS)
Lee, G. W.; Gangopadhyay, A. K.; Kelton, K. F.; Hyers, R. W.; Rathz, T. J.; Rogers, J. R.
2003-01-01
If crystallization can be avoided, liquids enter a metastable (undercooled) state below their equilibrium liquidus temperatures, TI, finally freezing into a glass below a characteristic temperature called the glass transition temperature, T,. In rare cases, the undercooled liquid may undergo a liquid-liquid phase transition (liquid polymorphism) before entering the glassy state. This has been suggested from experimental studies of HzO and Si4. Such phase transitions have been predicted in some stable liquids, i.e. above TI at atmospheric pressure, for Si02 and BeF;, but these have not been verified experimentally. They have been observed in liquids of P7, Sis and C9, but only under high pressure. All of these transitions are driven by an anomalous density change, i.e. change in local structure, with temperature or pressure. In this letter we present the first experimental evidence for a phase transition in a low viscosity liquid that is not driven by an anomalous density change, but by an approach to a constant configuration state. A maximum in the specific heat at constant pressure, similar to what is normally observed near T,, is reported here for undercooled low viscosity liquids of quasicrystal- forming Ti-Zr-Ni alloys. that includes cooperativity, by incorporating a temperature dependent excitation energy fits the data well, signaling a phase transition.
Medium-frequency impulsive-thrust-excited slosh waves during propellant reorientation with a geyser
NASA Technical Reports Server (NTRS)
Hung, R. J.; Shyu, K. L.; Lee, C. C.
1992-01-01
Slosh wave excitation induced by a resettling flowfield activated by 1.0-Hz impulsive thrust during the course of liquid reorientation with the initiation of geyser for liquid-fill levels of 30, 50, 65, 70, and 80 percent has been studied. Characteristics of slosh waves of various frequencies excited by the resettling flowfield are discussed. Slosh wave excitations shift the fluid mass distribution in the container which imposes time-dependent variations in spacecraft moment of inertia. This information is important for spacecraft control during the course of liquid reorientation.
Liquid-Liquid Extraction Processes
Fair, J. R.; Humphrey, J. L.
1983-01-01
the two liquid phases, separation will result. This is the principle upon which separation by liquid-liquid extraction is based, and there are a number of important applications of this concept in industrial processes. This paper will review the basic...
Marco Heinen; Simon K. Schnyder; John F. Brady; Hartmut Löwen
2015-05-05
We introduce fractal liquids by generalizing classical liquids of integer dimensions $d = 1, 2, 3$ to a fractal dimension $d_f$. The particles composing the liquid are fractal objects and their configuration space is also fractal, with the same non-integer dimension. Realizations of our generic model system include microphase separated binary liquids in porous media, and highly branched liquid droplets confined to a fractal polymer backbone in a gel. Here we study the thermodynamics and pair correlations of fractal liquids by computer simulation and semi-analytical statistical mechanics. Our results are based on a model where fractal hard spheres move on a near-critical percolating lattice cluster. The predictions of the fractal Percus-Yevick liquid integral equation compare well with our simulation results.
Fluorescent optical liquid level sensor
Weiss, Jonathan D. (Albuquerque, NM)
2001-01-01
A liquid level sensor comprising a transparent waveguide containing fluorescent material that is excited by light of a first wavelength and emits at a second, longer wavelength. The upper end of the waveguide is connected to a light source at the first wavelength through a beveled portion of the waveguide such that the input light is totally internally reflected within the waveguide above an air/liquid interface in a tank but is transmitted into the liquid below this interface. Light is emitted from the fluorescent material only in those portions of the waveguide that are above the air/liquid interface, to be collected at the upper end of the waveguide by a detector that is sensitive only to the second wavelength. As the interface moves down in the tank, the signal strength from the detector will increase.
Models for the phase transition between a Fermi liquid and fractional Chern insulator
NASA Astrophysics Data System (ADS)
Moore, Joel; Zaletel, Michael; Parameswaran, Siddharth
2014-03-01
A partially filled band with nonzero Chern density can support fractional quantum Hall states (``fractional Chern insulators'') as a consequence of repulsive interactions between electrons. In the absence of this repulsion, the ground state is generically a simple band metal with an anomalous Hall effect. There are several possible scenarios for a second-order transition between metallic and quantum Hall states, which can be approached as a composite-fermion band crossing, a coupling between Luttinger liquids, or via a parton construction. We discuss the extent to which these scenarios lead to different predictions and test those predictions by density-matrix renormalization group calculations. The authors acknowledge support from NSF DMR-1206515 (J.E.M. and M.Z.) and a Simons Foundation postdoctoral fellowship (S.P.).
by perturbing a static layer of glass beads on a rough inclined plane. We observe two distinct types. The experiments are done on an inclined plane covered with velvet cloth. This surface is chosen so that the glass to understanding their dynamics. When a pile of sand starts flowing, avalanches occur on its inclined free surface
2001-01-01
and electronic interactions in La2CuO4. Phys. Rev. Lett. 86, 53775380 (2001). 18. Kastner, M. A., Birgeneau, R, J. M. High-energy spin dynamics in La1.69Sr0.31NiO4. Phys. Rev. Lett. 90, 147202 (2003). 20. Boothroyd, A. T. et al. Spin dynamics in stripe-ordered La5/3Sr1/3NiO4. Phys. Rev. B 67, 100407 (2003). 21
Araki, T. (Kyoto Inst. of Tech. (Japan)); Tsukube, H. (Okayama Univ. (Japan))
1990-01-01
This work describes newer applications of liquid membrane systems which contain molecular and/or ion recognizing carrier compounds and the related characteristic membrane materials. It focuses on the current knowledge about chemistry, biology and related technology of liquid membranes. It reviews the most recent advances in design and characteristics of synthetic liquid membrane transport. Up-to-date topics in the analytical and separation science, plus biomimetic membrane technology are discussed.
Delayed fluorescence from upper excited singlet states of aromatic ketones
NASA Astrophysics Data System (ADS)
Nickel, Bernhard; Roden, Gabriele
1980-09-01
With liquid solutions of the aromatic ketones anthraquinone and xanthone, a P-type delayed fluorescence from upper excited singlet states, resulting from triplet-triplet annihilation, has been observed. Some peculiarities of the triplet-triplet annihilation of aromatic ketones are discussed.
Photothermal excitation setup for a modified commercial atomic force microscope
Adam, Holger; Rode, Sebastian; Schreiber, Martin; Kühnle, Angelika, E-mail: kuehnle@uni-mainz.de [Institute of Physical Chemistry, Johannes Gutenberg University Mainz, Duesbergweg 10-14, 55099 Mainz (Germany)] [Institute of Physical Chemistry, Johannes Gutenberg University Mainz, Duesbergweg 10-14, 55099 Mainz (Germany); Kobayashi, Kei; Yamada, Hirofumi [Department of Electronic Science and Engineering, Kyoto University, Katsura, Nishikyo, Kyoto 615-8510 (Japan)] [Department of Electronic Science and Engineering, Kyoto University, Katsura, Nishikyo, Kyoto 615-8510 (Japan)
2014-02-15
High-resolution imaging in liquids using frequency modulation atomic force microscopy is known to suffer from additional peaks in the resonance spectrum that are unrelated to the cantilever resonance. These unwanted peaks are caused by acoustic modes of the liquid and the setup arising from the indirect oscillation excitation by a piezoelectric transducer. Photothermal excitation has been identified as a suitable method for exciting the cantilever in a direct manner. Here, we present a simple design for implementing photothermal excitation in a modified Multimode scan head from Bruker. Our approach is based on adding a few components only to keep the modifications as simple as possible and to maintain the low noise level of the original setup with a typical deflection noise density of about 15 fm/?(Hz) measured in aqueous solution. The success of the modification is illustrated by a comparison of the resonance spectra obtained with piezoelectric and photothermal excitation. The performance of the systems is demonstrated by presenting high-resolution images on bare calcite in liquid as well as organic adsorbates (Alizarin Red S) on calcite with simultaneous atomic resolution of the underlying calcite substrate.
Photothermal excitation setup for a modified commercial atomic force microscope
NASA Astrophysics Data System (ADS)
Adam, Holger; Rode, Sebastian; Schreiber, Martin; Kobayashi, Kei; Yamada, Hirofumi; Kühnle, Angelika
2014-02-01
High-resolution imaging in liquids using frequency modulation atomic force microscopy is known to suffer from additional peaks in the resonance spectrum that are unrelated to the cantilever resonance. These unwanted peaks are caused by acoustic modes of the liquid and the setup arising from the indirect oscillation excitation by a piezoelectric transducer. Photothermal excitation has been identified as a suitable method for exciting the cantilever in a direct manner. Here, we present a simple design for implementing photothermal excitation in a modified Multimode scan head from Bruker. Our approach is based on adding a few components only to keep the modifications as simple as possible and to maintain the low noise level of the original setup with a typical deflection noise density of about 15 fm/sqrt{Hz} measured in aqueous solution. The success of the modification is illustrated by a comparison of the resonance spectra obtained with piezoelectric and photothermal excitation. The performance of the systems is demonstrated by presenting high-resolution images on bare calcite in liquid as well as organic adsorbates (Alizarin Red S) on calcite with simultaneous atomic resolution of the underlying calcite substrate.
NASA Astrophysics Data System (ADS)
Mikhelashvili, M. S.; Agam, O.
2004-10-01
The common theory of reversible charge transfer (RCT) at low donor system excitation power in liquids is examined. The space averaging procedures describing the kinetics of RCT in the liquid space are discussed. The reaction space is presented as a totality of independent subgroups with one excited donor and some group of acceptors effectively interacting only with the donor in the given “subgroup”. We have shown that the theory [3-5] gives questionable results for cation state probability for the usual parameters of this problem. If the acceptor concentration or the charge transfer rate constants are low, then the cation state probability behaves the same in the two theories [3-5] and [7, 8]. The correct account of the donor’s ground state change and charge back transfer in the RCT theory gives the new, not contradictory results, different from the behavior of the results in references [3-5], but near to results of [7, 8]. The molecules motion accelerates the ionization of donors and neutralization of ions. The influence of the motion of neutral and ionized molecules on charge transfer kinetics is different. The Coulomb interaction of ions is taken into account; the effect depends on the space averaging method used. The new approximation in this article in comparison with references [3-6,9] consists in the space averaging procedure of the donor cation state probability, which takes into account the donor’s ground state.
Spinon-phonon interaction in algebraic spin liquids
Serbyn, Maksym
Motivated by a search for experimental probes to access the physics of fractionalized excitations called spinons in spin liquids, we study the interaction of spinons with lattice vibrations. We consider the case of algebraic ...
Exciting flavored bound states
NASA Astrophysics Data System (ADS)
Rojas, E.; El-Bennich, B.; de Melo, J. P. B. C.
2014-10-01
We study ground and radial excitations of flavor singlet and flavored pseudoscalar mesons within the framework of the rainbow-ladder truncation using an infrared massive and finite interaction in agreement with recent results for the gluon-dressing function from lattice QCD and Dyson-Schwinger equations. Whereas the ground-state masses and decay constants of the light mesons as well as charmonia are well described, we confirm previous observations that this truncation is inadequate to provide realistic predictions for the spectrum of excited and exotic states. Moreover, we find a complex conjugate pair of eigenvalues for the excited D(s) mesons, which indicates a non-Hermiticity of the interaction kernel in the case of heavy-light systems and the present truncation. Nevertheless, limiting ourselves to the leading contributions of the Bethe-Salpeter amplitudes, we find a reasonable description of the charmed ground states and their respective decay constants.
Bremond, Nicolas; Bibette, Jérôme
2010-01-01
This fluid dynamics video reports how to form liquid core capsules having a thin hydrogel elastic membrane named liquid pearls. These fish-egg like structures are initially made of a millimetric liquid drop, aqueous or not, coated with an aqueous liquid film containing sodium alginate that gels once the double drop enters a calcium chloride bath. The creation of such pearls with micrometer thick membrane requires to suppress mixing until gelling takes place. Here, we show that superimposing a two dimensional surfactant precipitation at the interface confers a transient rigidity that can damp the shear induced instability at impact. Based on this, pearls containing almost any type of liquids can be created. The video focuses on the dynamics of the entry of the compound drop into the gelling bath.
A Direct-View Backlight With UV Excited Trichromatic Phosphor Conversion Film
Hsin-Tao Huang; Chuang-Chuang Tsai; Yi-Pai Huang
2010-01-01
This work presents a novel ultraviolet (UV) excited flat lighting (UFL) system consisting of remote phosphor converter (RPC) for liquid-crystal display (LCD) backlight applications. A trichromatic RPC is excited using 254 nm UV lamps to achieve a slim, high color saturation and high luminance backlight. Experimental results indicate that the module thickness reduces to 14.5 mm, along with a high
Interfacial Phenomena of Magnetic Fluid with Permanent Magnet in a Longitudinally Excited Container
Seiichi Sudo; Hirofumi Wakuda; Tetsuya Yano
2008-01-01
This paper describes the magnetic fluid sloshing in a longitudinally excited container. Liquid responses of magnetic fluid with a permanent magnet in a circular cylindrical container subject to vertical vibration are investigated. Experiments are performed on a vibration- testing system which provided longitudinal excitation. A cylindrical container made with the acrylic plastic is used in the experiment. A permanent magnet
Liquid metal thermoacoustic engine
Swift, G.W.; Migliori, A.; Wheatley, J.C.
1986-01-01
We are studying a liquid metal thermoacoustic engine both theoretically and experimentally. This type of engine promises to produce large quantities of electrical energy from heat at modest efficiency with no moving parts. A sound wave is usually thought of as consisting of pressure oscillations, but always attendant to the pressure oscillation are temperature oscillations. The combination produces a rich variety of ''thermoacoustic'' effects. These effects are usually so small that they are never noticed in everyday life; nevertheless under the right circumstances they can be harnessed to produce powerful heat engines, heat pumps, and refrigerators. In our liquid metal thermoacoustic engine, heat flow from a high temperature source to a low temperature sink generates a high-amplitude standing acoustic wave in liquid sodium. This acoustic power is converted to electric power by a simple magnetohydrodynamic effect at the acoustic oscillation frequency. We have developed a detailed thermoacoustic theory applicable to this engine, and find that a reasonably designed liquid sodium engine operating between 700/sup 0/C and 100/sup 0/C should generate about 60 W/cm/sup 2/ of acoustic power at about 1/3 of Carnot's efficiency. Construction of a 3000 W-thermal laboratory model engine has just been completed, and we have exciting preliminary experimental results as of the time of preparation of this manuscript showing, basically, that the engine works. We have also designed and built a 1 kHz liquid sodium magnetohydrodynamic generator and have extensive measurements on it. It is now very well characterized both experimentally and theoretically. The first generator of its kind, it already converts acoustic power to electric power with 40% efficiency. 16 refs., 5 figs.
Spintronics, propagating mode, (quantum) spin transport, and new electron liquids
NASA Astrophysics Data System (ADS)
Bernevig, B. Andrei
2006-03-01
The field of spintronics deals with the physics of the electron-spin in semiconductors, metals, insulators and other materials. Among these, the systems which are characterized by strong spin-orbit coupling hold a special place and exhibit a plethora of new phenomena. In classical transport in semiconductors, a propagating spin-charge collective mode appears that is qualitatively different from the diffusive charge transport. The propagating spin-charge mode is the hallmark of spin-orbit coupled systems with a Fermi surface. The Boltzmann transport equations are qualitatively different from the diffusive normal behavior. Three dimensional bulk transport will be analyzed for the first time. In semiconductors without spin-orbit coupling, an orbital Hall effect (similar to the spin-Hall effect) is present in which electrons selectively occupy different orbitals depending on their direction of motion. In quantum transport, a spatially varying spin-orbit coupling is equivalent to a Landau level problem in which electrons of opposite spin feel opposite magnetic fields, thereby exhibiting a quantum Spin-Hall effect. Time-reversal symmetry is unbroken. In these spin Hall insulators, the quantum spin transport takes place through edge states that cross the bulk gap and the Fermi level. The electron liquid on the edges is a helical liquid, in which spin is correlated with chirality, and represents a new class of one-dimensional liquids different from the Luttinger spinless, spinful or chiral liquids. I will also briefly discuss the possibility of three-dimensional quantization in systems with spin-orbit coupling. New experiments are needed and proposed to verify these predictions.
NASA Technical Reports Server (NTRS)
Parcell, L. A.; Mceachran, R. P.; Stauffer, A. D.
1990-01-01
The differential and total cross section for the excitation of the 3s1P10 and 3p1P1 states of neon by positron impact were calculated using a distorted-wave approximation. The results agree well with experimental conclusions.
Colin Morningstar
2008-10-24
Progress in extracting the spectrum of excited hadron resonances is reviewed and the key issues and challenges in such computations are outlined. The importance of multi-hadron states as simulations are done with lighter pion masses is discussed, and the need for all-to-all quark propagators is emphasized.
NSDL National Science Digital Library
2012-06-26
Young learners investigate and observe the properties of three liquids -- water, vegetable oil, and corn syrup. They use their senses to collect data and ask and answer questions. This lesson for young learners introduces the scientific process.
Boyer, Edmond
. Abstract. - Photoemission measurements of liquid mercury and liquid A1 are reported for photon energies up aluminium and liquid mercury which follow the same pattern as the earlier results. In the following we samples. Exciting radiation was obtained using either a hydrogen discharge lamp coupled to a vacuum ultra
Apparatus for photon excited catalysis
NASA Technical Reports Server (NTRS)
Saffren, M. M. (inventor)
1977-01-01
An apparatus is described for increasing the yield of photonically excited gas phase reactions by extracting excess energy from unstable, excited species by contacting the species with the surface of a finely divided solid.
Pulse excitation of bolometer bridges
NASA Technical Reports Server (NTRS)
Rusk, S. J.
1972-01-01
Driving bolometer bridge by appropriately phased excitation pulses increases signal-to-noise ratio of bolometer sensor which operates on a chopped light beam. Method allows higher applied voltage than is possible by conventional ac or dc excitation.
Luminescence of liquid nitrogen after exposure to pulsed UV radiation
NASA Astrophysics Data System (ADS)
Kirko, D. L.
2015-04-01
The optical characteristics of sustained weak luminescence of liquid nitrogen were studied after exposure to a pulse of UV radiation. The luminescence consisted of a bulk emission of the liquid and localized luminous regions. The luminescence spectrum of liquid nitrogen in UV-VIS range was studied. The UV radiation parameters that influence the excitation of the luminescence of liquid nitrogen were investigated. A possible scheme of bulk luminescence of liquid nitrogen and a hypothesis of the formation of localized luminous regions were discussed.
Harmonically excited orbital variations
Morgan, T.
1985-08-06
Rephrasing the equations of motion for orbital maneuvers in terms of Lagrangian generalized coordinates instead of Newtonian rectangular cartesian coordinates can make certain harmonic terms in the orbital angular momentum vector more readily apparent. In this formulation the equations of motion adopt the form of a damped harmonic oscillator when torques are applied to the orbit in a variationally prescribed manner. The frequencies of the oscillator equation are in some ways unexpected but can nonetheless be exploited through resonant forcing functions to achieve large secular variations in the orbital elements. Two cases are discussed using a circular orbit as the control case: (1) large changes in orbital inclination achieved by harmonic excitation rather than one impulsive velocity change, and (2) periodic and secular changes to the longitude of the ascending node using both stable and unstable excitation strategies. The implications of these equations are also discussed for both artificial satellites and natural satellites. For the former, two utilitarian orbits are suggested, each exploiting a form of harmonic excitation. 5 refs.
Temperature and excitable cells
Fillafer, Christian; Schneider, Matthias F
2013-01-01
Temperature affects a host of biological processes, one of which is the conduction velocity of action potentials (AP). The velocity-temperature profile of APs has remained remarkably conserved across excitable animal and plant cells. Herein, we will not analyze this behavior in terms of temperature sensitivities of single molecules (e.g., ion channels), but rather we present a phenomenological thermodynamic interpretation. By assuming that APs are acoustic phenomena, one arrives at testable predictions about the temperature-dependence of the macroscopic material properties of the excitable cell membrane. These material properties set constraints on the excitability of a cell membrane and allow us to hypothesize about its typical relaxation timescales. The presented approach—by virtue of its thermodynamic nature—is by no means limited to temperature. It applies equally well to all thermodynamic variables (e.g., mechanical stretch, pH, ion concentrations, etc.) and to underline this argument we discuss some implications and predictions for sensory physiology. PMID:24563710
Quantum Computing with Electrons Floating on Liquid
Dykman, Mark
Quantum Computing with Electrons Floating on Liquid Helium P. M. Platzman1 * and M. I. Dykman2 excited electrons from the surface. There is much interest in constructing analog quantum computers (AQC quantum computation is a more diffi- cult problem because these physical systems must consist
Electron-beam pumped liquid excimer lasers
Loree, T.R.; Showalter, R.R.; Johnson, T.M.; Birmingham, B.S.; Hughes, W.M.
1988-01-01
We have investigated the excimers formed in liquid argon when various cryogenic gas mixes were excited by 1-MeV electrons. Fluorescence was detected from many excimers at their new red-shifted wavelengths, and XeO, Xe/sub 2/, and Kr/sub 2/ were lased. 25 refs., 12 figs.
Get excited: reappraising pre-performance anxiety as excitement.
Brooks, Alison Wood
2014-06-01
Individuals often feel anxious in anticipation of tasks such as speaking in public or meeting with a boss. I find that an overwhelming majority of people believe trying to calm down is the best way to cope with pre-performance anxiety. However, across several studies involving karaoke singing, public speaking, and math performance, I investigate an alternative strategy: reappraising anxiety as excitement. Compared with those who attempt to calm down, individuals who reappraise their anxious arousal as excitement feel more excited and perform better. Individuals can reappraise anxiety as excitement using minimal strategies such as self-talk (e.g., saying "I am excited" out loud) or simple messages (e.g., "get excited"), which lead them to feel more excited, adopt an opportunity mind-set (as opposed to a threat mind-set), and improve their subsequent performance. These findings suggest the importance of arousal congruency during the emotional reappraisal process. PMID:24364682
Coupled-wire construction of chiral spin liquids
NASA Astrophysics Data System (ADS)
Meng, Tobias; Neupert, Titus; Greiter, Martin; Thomale, Ronny
2015-06-01
We develop a coupled-wire construction of chiral spin liquids. The starting points are individual wires of electrons in the Mott regime that are subject to a Zeeman field and Rashba spin-orbit coupling. Suitable spin-flip couplings between the wires yield an Abelian chiral spin liquid state which supports spinon excitations above a bulk gap and chiral edge states. The approach generalizes to non-Abelian chiral spin liquids at level k with parafermionic edge states.
Aussillous, P; Quéré, D
2001-06-21
The transport of a small amount of liquid on a solid is not a simple process, owing to the nature of the contact between the two phases. Setting a liquid droplet in motion requires non-negligible forces (because the contact-angle hysteresis generates a force opposing the motion), and often results in the deposition of liquid behind the drop. Different methods of levitation-electrostatic, electromagnetic, acoustic, or even simpler aerodynamic techniques-have been proposed to avoid this wetting problem, but all have proved to be rather cumbersome. Here we propose a simple alternative, which consists of encapsulating an aqueous liquid droplet with a hydrophobic powder. The resulting 'liquid marbles' are found to behave like a soft solid, and show dramatically reduced adhesion to a solid surface. As a result, motion can be generated using gravitational, electrical and magnetic fields. Moreover, because the viscous friction associated with motion is very small, we can achieve quick displacements of the droplets without any leaks. All of these features are of potential benefit in microfluidic applications, and also permit the study of a drop in a non-wetting situation-an issue of renewed interest following the recent achievement of super-hydrophobic substrates. PMID:11418851
Vacuum ultraviolet electronic properties of liquids
Painter, L.R.
1989-01-01
The principal aim of this program has been to study the electronic structure of insulating liquids of biological interest over a broad energy range from 0 to 30 eV. The studies basically consist of measuring the reflectance, transmittance, photoemission and photoionization of dielectric liquids in the vacuum ultraviolet spectral region as a function of angle of incidence and energy. these in turn may be interpreted in terms of the electronic structure of each liquid as it is excited by the passage of a charged particle. Optical data provides indirect evidence that collective effects occur in liquids. Direct observation of their existence is substantiated in studies of the energy distribution of electrons specularly scattered from the liquid surface.
S. Subhash Babu; S. K. Bhattacharyya
1996-01-01
Fluid-structure interaction problems, which may be categorized into different types, have attracted the attention of engineers because of their numerous practical applications. Sloshing of liquid in a liquid filled container subjected to external excitations and coupled interaction between the liquid and container wall due to sloshing is one such problem. The focus of the present paper is on the development
Multiphonon excitations in boson quantum films
Clements, B.E. [Institute Laue Langevin, 38042 Grenoble Cedex (France)] [Institute Laue Langevin, 38042 Grenoble Cedex (France); [Department of Physics, Texas A& M University, College Station, Texas 77843 (United States); Krotscheck, E. [Institut fuer Theoretische Physik, Johannes Kepler Universitaet, A-4040 Linz (Austria)] [Institut fuer Theoretische Physik, Johannes Kepler Universitaet, A-4040 Linz (Austria); [Department of Physics, Texas A& M University, College Station, Texas 77843 (United States); Tymczak, C.J. [Department of Physics, Texas A& M University, College Station, Texas 77843 (United States)] [Department of Physics, Texas A& M University, College Station, Texas 77843 (United States)
1996-05-01
Dynamical excitations in thin liquid films of {sup 4}He adsorbed to a substrate are investigated by using a microscopic theory of excitations that includes multiple-phonon scattering. We study the dispersion relation, excitation mechanisms, transition densities, and particle currents as a function of surface coverage. A primary new result is that we have included three-phonon scattering processes in the calculation of the dynamic structure function and the one-body current densities. With the exception that our ground state is determined by our variational theory, rather than taken from experiment, our work on the dynamic structure function is the generalization of that of Jackson [Phys. Rev. A {bold 4}, 2386 (1971)] to inhomogeneous systems (films). Using sum rules for the dynamic structure function as a guide, we suggest a simple scaling argument for improving the agreement between our dynamic structure function and the experimental one. The addition of three-phonon contributions bring about the following changes. First, the energy of most modes is lowered by a non-negligible amount for finite momentum excitations. Second, the film{close_quote}s surface mode is the exception; it is only slightly affected. Third, for monolayer films there is large scattering at high energies at intermediate values of momenta. This scattering can be traced back to an anomalously large contribution to the two-particle density of states. Fourth, all modes with energy above a critical energy decay, and the associated peaks of the dynamic structure function are broadened. Fifth, the maxonlike character is enhanced in the bulklike modes. {copyright} {ital 1996 The American Physical Society.}
Search for Gluonic Excitations
Paul Eugenio
2007-10-01
Studies of meson spectra via strong decays provide insight regarding QCD at the confinement scale. These studies have led to phenomenological models for QCD such as the constituent quark model. However, QCD allows for a much richer spectrum of meson states which include extra states such as exotics, hybrids, multi-quarks, and glueballs. First discussion of the status of exotic meson searches is given followed by a discussion of plans at Jefferson Lab to double the energy of the machine to 12 GeV, which will allow us to access photoproduction of mesons in search for gluonic excited states.
Search for Gluonic Excitations
Eugenio, Paul [Florida State University, Department of Physics, Tallahassee, Florida 32306 (United States)
2007-10-26
Studies of meson spectra via strong decays provide insight regarding QCD at the confinement scale. These studies have led to phenomenological models for QCD such as the constituent quark model. However, QCD allows for a much richer spectrum of meson states which include extra states such as exotics, hybrids, multi-quarks, and glueballs. First discussion of the status of exotic meson searches is given followed by a discussion of plans at Jefferson Lab to double the energy of the machine to 12 GeV, which will allow us to access photoproduction of mesons in search for gluonic excited states.
NSDL National Science Digital Library
The Concord Consortium
2011-12-13
Investigate how atoms can be excited to give off radiation (photons) with models of electron energy diagrams. Explore the effects of energy levels in atoms through interactive computer models. Learn about the different electron orbitals of an atom, and explore three-dimensional models of the atoms. Learn about photons and why they are emitted, and gain an understanding of the link between energy levels and photons as you discover how an atom?s electron configuration affects which wavelengths of light it will admit or absorb.
Rocking response of tanks containing two liquids
Tang, Yu; Chang, Y.W.
1993-06-01
Liquid storage tanks are important components of industrial facilities and, when located in earthquake prone regions, should be designed to withstand the earthquakes to which they may be subjected. There are cases in which the density of the tank content is not uniform. For such cases, the dynamic responses of tanks containing liquids with different densities must be studied. A study on the dynamic response of upright circular cylindrical liquid-storage tanks containing two different liquids under a rock base motion with an arbitrary temporal variation is presented. Only rigid tanks were studied. The response quantities examined include the hydrodynamic pressure, sloshing wave height and the associated frequencies, base shear and moments. Each of these response quantities is expressed as the sum of the so-called impulsive component and convective component. Unlike the case of tanks containing one liquid, in which the response is controlled by one parameter, height-to-radius ratio, the response of tanks containing two different liquids are controlled by three parameters: height-to-radius ratio, and mass density ratio and height ratio of the two liquids. The interrelationship of the responses of the tank-liquid system to rocking and lateral base excitations is established by examining numerical results extensively. It is found that some of the response quantities for a tank-liquid system under a rocking base motion can be determined from the corresponding response quantities for an identical tank under a horizontal base motion.
Sarkar, Suman; Paswan, Anil; Prakas, S
2014-01-01
Human have lungs to breathe air and they have no gills to breath liquids like fish. When the surface tension at the air-liquid interface of the lung increases as in acute lung injury, scientists started to think about filling the lung with fluid instead of air to reduce the surface tension and facilitate ventilation. Liquid ventilation (LV) is a technique of mechanical ventilation in which the lungs are insufflated with an oxygenated perfluorochemical liquid rather than an oxygen-containing gas mixture. The use of perfluorochemicals, rather than nitrogen as the inert carrier of oxygen and carbon dioxide offers a number of advantages for the treatment of acute lung injury. In addition, there are non-respiratory applications with expanding potential including pulmonary drug delivery and radiographic imaging. It is well-known that respiratory diseases are one of the most common causes of morbidity and mortality in intensive care unit. During the past few years several new modalities of treatment have been introduced. One of them and probably the most fascinating, is of LV. Partial LV, on which much of the existing research has concentrated, requires partial filling of lungs with perfluorocarbons (PFC's) and ventilation with gas tidal volumes using conventional mechanical ventilators. Various physico-chemical properties of PFC's make them the ideal media. It results in a dramatic improvement in lung compliance and oxygenation and decline in mean airway pressure and oxygen requirements. No long-term side-effect reported. PMID:25886321
NSDL National Science Digital Library
John Eichinger
2009-05-30
This activity involves an exploration of density. Why does oil float on water? How does drain cleaner sink down into the clogged pipe right through standing water? These questions will be answered as students make a layered "parfait" of colored liquids ba
Hybrid excitation synchronous generators for island operation
K. Kamiev; J. Nerg; J. Pyrho?nen; V. Zaboin
2010-01-01
The paper discusses Hybrid Excitation Synchronous Machines (HESMs) principles and their application possibilities. HESMs combine both features of traditional wound field synchronous machines (SMs) and permanent magnet synchronous machines (PMSMs). Such electrical machines have two different rotor excitation sources: PM excitation and wound field excitation. The wound field excitation is used to control the excitation flux in the air gap,
NASA Astrophysics Data System (ADS)
Mead, Roy D.
This dissertation describes high-resolution tunable laser photodetachment studies of both valence and dipole -bound excited states of negative ions. Also discussed is a merged laser-ion beam photodetachment spectrometer. The photodetachment cross section of C(,2)('-) displays many sharp resonances, due to excitation of autodetaching levels of the B('2)(SIGMA)(,u)('+) valence state lying above the onset of the (C(,2) + e) continuum. The positions of approximately 1,000 resonances were measured, allowing the spectroscopic constants of the ground X('2)(SIGMA)(,g)('+) and excited B('2)(SIGMA)(,u)('+) states to be determined, including spin-rotation constants. The previously unobserved A('2)(PI)(,u) state has been characterized by deperturbation analysis. Strong A-X transitions are predicted near 2.5 microns. The widths of C(,2)('-) resonances with v = 6 -10 and J = 1-60 have also been measured, providing autodetachment rates as a function of both rotation and vibration, ranging from 10('8) to 10('11) s('-1). The first conclusive observation of an entirely new class of states, called dipole-bound or dipole-supported states, is discussed for the case of acetaldehyde enolate (vinyl oxide) negative ion. In these novel states, the extra electron is weakly bound ((TURN)5 cm('-1)) in a very diffuse orbital ((TURN)100 (ANGSTROM)) by the dipole moment of the neutral core. Weak electric fields (< 70 V/cm) are found to rapidly detach the dipole-bound electron. These dipole-bound states resemble Rydberg states of neutrals, but differ from Rydbergs in many important respects. They should be present for all neutrals with dipole moments > 2 Debye. The merged laser-ion beam (also known as coaxial -beams) spectrometer has 0.0005 cm('-1) resolution in the visible region, simultaneously achieving very high sensitivity. It employs quadrupole beam deflectors to merge and laser and negative ion beams, and can scan spectra either by scanning the laser frequency or the Doppler shift of the ion beam. Both electrons and neutral photodetachment products are detected. Even very low energy electrons (< 20 meV) are collected and counted, and the collector may be adjusted to collect either all electrons or only low energy electrons as needed.
NASA Technical Reports Server (NTRS)
Elliott, D. G.
1986-01-01
Boiling liquids pumped by device based on proven components. Expanding saturated liquid in nozzle and diverting its phases along separate paths in liquid/vapor separator raises pressure of liquid. Liquid cooled in process. Pump makes it unnecessary to pressurize cryogenic liquids in order to pump them. Problems of introducing noncondensable pressurizing gas avoided.
Fusion excitation function revisited
Ph. Eudes; Z. Basrak; F. Sébille; V. de la Mota; G. Royer; M. Zori?
2012-09-28
We report on a comprehensive systematics of fusion-evaporation and/or fusion-fission cross sections for a very large variety of systems over an energy range 4-155 A.MeV. Scaled by the reaction cross sections, fusion cross sections do not show a universal behavior valid for all systems although a high degree of correlation is present when data are ordered by the system mass asymmetry.For the rather light and close to mass-symmetric systems the main characteristics of the complete and incomplete fusion excitation functions can be precisely determined. Despite an evident lack of data above 15A.MeV for all heavy systems the available data suggests that geometrical effects could explain the persistence of incomplete fusion at incident energies as high as 155A.MeV.
Laser cooling and control of excitations in superfluid helium
Harris, G I; Sheridan, E; Sachkou, Y; Baker, C; Bowen, W P
2015-01-01
Superfluidity is an emergent quantum phenomenon which arises due to strong interactions between elementary excitations in liquid helium. These excitations have been probed with great success using techniques such as neutron and light scattering. However measurements to-date have been limited, quite generally, to average properties of bulk superfluid or the driven response far out of thermal equilibrium. Here, we use cavity optomechanics to probe the thermodynamics of superfluid excitations in real-time. Furthermore, strong light-matter interactions allow both laser cooling and amplification of the thermal motion. This provides a new tool to understand and control the microscopic behaviour of superfluids, including phonon-phonon interactions, quantised vortices and two-dimensional quantum phenomena such as the Berezinskii-Kosterlitz-Thouless transition. The third sound modes studied here also offer a pathway towards quantum optomechanics with thin superfluid films, including femtogram effective masses, high me...
NASA Astrophysics Data System (ADS)
Zakharov, V. I.
2015-05-01
We review briefly properties of chiral liquids, or liquids with massless fermionic constituents. We concentrate on three effects, namely, the low ratio of viscosity ? to entropy density s, chiral magnetic and vortical effects. We sketch standard derivations of these effects in the hydrodynamic approximation and then concentrate on possibile unifying approach which is based on consideration of the (anomalously) conserved axial current. The point is that the conservation of chirality is specific for the microscopic, field-theoretic description of massless fermions and their interactions. On the macroscopic side, the standard hydrodynamic equations are not consistent, generally speaking, with conservation of a helical macroscopic motion. Imposing extra constraints on the hydrodynamics might resolve this "clash-of-symmetries" paradox.
Optically excited states in positronium
NASA Technical Reports Server (NTRS)
Howell, R. H.; Ziock, Klaus P.; Magnotta, F.; Dermer, Charles D.; Failor, R. A.; Jones, K. M.
1990-01-01
Optical excitation are reported of the 1 3S-2 3P transition in positronium, and a second excitation from n=2 to higher n states. The experiment used light from two pulsed dye lasers. Changes in the positronium annihilation rate during and after the laser pulse were used to deduce the excited state populations. The n=2 level was found to be saturable and excitable to a substantial fraction of n=2 positronium to higher levels. Preliminary spectroscopic measurements were performed on n=14 and n=15 positronium.
Metastable Quasimolecules in Excited Gases
V. N. Malnev; R. A. Naryshkin
2008-09-09
Quasimolecules, which consist of two differently excited atoms in a resonantly excited gas, are considered. The energy of dissociation and typical sizes of such molecules are calculated in the first order of quantum-mechanical perturbation theory with the help of the dipole-dipole interaction operator. It is shown that there exist metastable quasimolecules, whose dipole radiative transition to the ground state (two non-excited atoms) is forbidden. The lifetime of such molecules is estimated and it is shown that quasimolecules may considerably affect the transport processes in a resonantly excited gas.
Toward realistic effective models of quantum-Hall edges
U. Zülicke; A. H. MacDonald
1997-01-01
We have investigated the dynamical properties of edge excitations in the (fractional) quantum-Hall regime for a sharp confining potential, emphasizing the effects resulting from the presence of long-range interaction. Our study uses chiral-Luttinger-liquid models that are motivated by the close analogy between the physics of edge excitations and that of plasmons in quasi-one-dimensional electron systems. We find that incorporating realistic
NASA Technical Reports Server (NTRS)
Martin, Robert B. (Inventor)
1997-01-01
A device for mixing liquid nitrogen and liquid oxygen to form liquid air. The mixing device consists of a tube for transferring liquid oxygen positioned within a tube for transferring liquid nitrogen. Supply vessels for liquid oxygen and liquid nitrogen are equally pressurized and connected to the appropriate tubes. Liquid oxygen and nitrogen flow from the supply vessels through the respective tubes and are mixed to form liquid air upon exiting the outlets of the tube. The resulting liquid air is transferred to a holding vessel.
Pool boiling heat transfer characteristics of liquid 3 He below 1 K
M. Maeda; A. Beppu; Y. Fujii; T. Shigi
2000-01-01
Heat transfer characteristics from a flat smooth copper surface to liquid 3He have been studied between 0.5 and 1 K under saturated vapor pressure. Liquid 3He behaves as normal liquid down to the lowest temperature among all substances, and has no pre-exciting bubble nucleus and dissolved liquids because of the lowest boiling point and the small surface tension. Therefore, it
Loss, Daniel
and the dynamic structure factor of spin liquids on the kagome lattice Matthias Punk1,2, Debanjan Chowdhury1 and gapless spin liquids28 , which give rise to sharp dispersing features in the dynamic structure factor9,10 , the measured dynamic structure factor reveals an excitation continuum that is remarkably flat as a function
Attosecond Photoscopy of Plasmonic Excitations
NASA Astrophysics Data System (ADS)
Lupetti, Mattia; Hengster, Julia; Uphues, Thorsten; Scrinzi, Armin
2014-09-01
We propose an experimental arrangement to image, with attosecond resolution, transient surface plasmonic excitations. The required modifications to state-of-the-art setups used for attosecond streaking experiments from solid surfaces only involve available technology. Buildup and lifetimes of surface plasmon polaritons can be extracted and local modulations of the exciting optical pulse can be diagnosed in situ.
Analysis of polyphase brushless exciter
Xiaochuan Jia; Jih-Sheng Jason Lai; Byeong-Mun Song
2000-01-01
This paper presents modeling and simulation of the operation of an 11 phase brushless exciter. The analytical method is based on Kron's tensor method, which is developed for dealing efficiently with the time-varying topology of an exciter circuit during a digital computer solution. The inductances, which are variable with rotor position, are calculated by the 2-D FEM method. The detailed
High slope efficiency liquid crystal lasers
NASA Astrophysics Data System (ADS)
Mowatt, Carrie; Morris, Stephen M.; Wilkinson, Timothy D.; Coles, Harry J.
2010-12-01
In this letter, we demonstrate high slope efficiency laser emission from reflective liquid crystal laser devices with a silicon backplane. Three different cell architectures were fabricated and each resulting laser device was then characterized in terms of the excitation threshold and the slope efficiency when optically excited close to the absorption maximum of the gain medium (pyrromethene 597). By combining a high gain medium with double-pass geometry, as well as the optimum cell thickness, the results demonstrate that it is possible to reduce thresholds by 25% and achieve slope efficiencies as high as 60%.
NASA Technical Reports Server (NTRS)
Bechert, D. W.
1982-01-01
The generation of instability waves in free shear layers is investigated. The model assumes an infinitesimally thin shear layer shed from a semi-infinite plate which is exposed to sound excitation. The acoustical shear layer excitation by a source further away from the plate edge in the downstream direction is very weak while upstream from the plate edge the excitation is relatively efficient. A special solution is given for the source at the plate edge. The theory is then extended to two streams on both sides of the shear layer having different velocities and densities. Furthermore, the excitation of a shear layer in a channel is calculated. A reference quantity is found for the magnitude of the excited instability waves. For a comparison with measurements, numerical computations of the velocity field outside the shear layer were carried out.
Hoagland, H.; Crozier, W. J.
1931-01-01
Rotation of an inclined surface on which Helix is creeping straight upward, such that the axis of the animal is turned at a right angle to its previous position, but in the same plane, leads to negatively geotropic orientation after a measurable latent period or reaction time. The duration of the latent period is a function of the slope of the surface. The magnitude of the standard deviation of the mean latent period is directly proportional to the mean latent period itself, so that the relative variability of response is constant. The dependence of reaction time upon extent of displacement from symmetrical orientation in the gravitational field is found also by tilting the supporting surface, without rotation in the animal's own plane. On slopes up to 55°, the relation between latent period and the sine of the slope is hyperbolic; above this inclination, the latent period sharply declines. This change in the curve is not affected by the attachment of moderate loads to the snail's shell (up to 1/3 of its own mass), and is probably a consequence of loss of passive stable equilibrium when rotated. When added loads do not too greatly extend the snail's anterior musculature, the latent period for the geotropic reaction is decreased, and, proportionately, its ?. These facts are discussed from the standpoint that geotropic excitation in these gasteropods is due to impressed muscle-tensions. PMID:19872624
NSDL National Science Digital Library
Mid-continent Research for Education and Learning (McREL)
2004-01-01
In this density activity, students determine the relative densities of five liquids and layer them atop one another in a straw. Directions for conducting the activity are included in addition to lists of the science process skills, complex reasoning strategies, and National Science Education Standards that relate to it. A brief explanation of the activity's science content and an assessment idea are also provided. This activity is part of a set called Whelmers that were designed to inspire students to think about science concepts.
Ekechukwu, A.A.
1994-07-05
A dropping electrolyte electrode is described for use in electrochemical analysis of non-polar sample solutions, such as benzene or cyclohexane. The liquid electrode, preferably an aqueous salt solution immiscible in the sample solution, is introduced into the solution in dropwise fashion from a capillary. The electrolyte is introduced at a known rate, thus, the droplets each have the same volume and surface area. The electrode is used in making standard electrochemical measurements in order to determine properties of non-polar sample solutions. 2 figures.
A. A. Zakharenko
2007-01-01
The experimental results of creating bulk elementary excitations (BEEs) in isotopically pure liquid helium-II by helium atomic beams at low temperatures ? 60 mK are presented. In the present experiment, BEE signals generated by He-atomic beams incident on the liquid free surface were detected by a bolometer positioned in the liquid helium-II. Some detected signals were very weak and depended
Comaskey, Brian J. (Walnut Creek, CA); Ault, Earl R. (Livermore, CA); Kuklo, Thomas C. (Oakdale, CA)
2005-07-05
A high average power, low optical distortion laser gain media is based on a flowing liquid media. A diode laser pumping device with tailored irradiance excites the laser active atom, ion or molecule within the liquid media. A laser active component of the liquid media exhibits energy storage times longer than or comparable to the thermal optical response time of the liquid. A circulation system that provides a closed loop for mixing and circulating the lasing liquid into and out of the optical cavity includes a pump, a diffuser, and a heat exchanger. A liquid flow gain cell includes flow straighteners and flow channel compression.
Guidance Document Cryogenic Liquids
are liquid nitrogen, liquid argon and liquid helium. The different cryogens become liquids under different oxygen could produce an oxygen-rich atmosphere which could accelerate combustion of other materials cryogenic liquid. But materials such as carbon steel, plastic and rubber become brittle and may fracture
Rocking response of tanks containing two liquids
Tang, Y. [Argonne National Lab., IL (United States). Reactor Engineering Div.
1995-01-01
A study on the dynamic response of upright circular cylindrical liquid-storage tanks containing two different liquids under a rocking base motion with an arbitrary temporal variation is presented. Only rigid tanks were studied. The response quantities examined include the hydrodynamic pressure, sloshing wave height and the associated frequencies, base shear and moments. Each of these response quantities is expressed as the sum of the so-called impulsive component and convective component. Unlike the case of tanks containing one liquid, in which the response is controlled by one parameter, height-to-radius ratio, the response of tanks containing two different liquids are controlled by three parameters: height-to-radius ratio, and mass density ratio and height ratio of the two liquids. The interrelationship of the responses of the tank-liquid system to rocking and lateral base excitations is established by examining numerical results extensively. The study shows that some of the response quantities for tank-liquid system under a rocking base motion can be determined from the available data for the response of an identical tank under a horizontal base motion. Base rocking motion can occur in a ground-supported tank or in an elevated tank under earthquake motions.
Magnetic impurity in a U(1) spin liquid with a spinon Fermi surface
Ribeiro, P.
We address the problem of a magnetic impurity in a two-dimensional U(1) spin liquid where the spinons have gapless excitations near the Fermi surface and are coupled to an emergent gapless gauge field. Using a large N ...
Multiple exciton generation and singlet fission: the role of collective effects
NASA Astrophysics Data System (ADS)
Eaves, Joel; Sweeney, Mark; Teichen, Paul; Strong, Steven
2014-03-01
Materials that relax to multiply excited states present exciting possibilities for overcoming the Shockley-Queisser limit in photovoltaic devices. For an excited electronic state to relax in this manner, electron-electron couplings must be strong relative to electron-phonon couplings. In this talk, I will discuss some ways in which these criteria may be met. I will discuss our work on multiple exciton generation in single-walled carbon nanotubes using Luttinger liquid theory and on singlet fission in molecular crystals using quantum exciton models. The Luttinger liquid theory focuses on the long wavelength part of the Coulomb interaction between electrons, and therefore allows us to assess the suspected role that dimensionality plays in enhancing electron-electron interactions. I will also discuss our results for quantum lattice models of singlet fission in molecular crystals that allows us to examine collective dynamical effects that contribute to efficient fission.
Industrial applications of photonuclear resonance excitation
Chichester, David Lee, 1971-
2000-01-01
Photonuclear resonance excitation refers to a variety of photonuclear interaction processes that lead to the excitation of a nucleus from some initial state to a higher energy nuclear state. Typical excited nuclear state ...
ERIC Educational Resources Information Center
Bradshaw, Madeline J.
1983-01-01
The nature of liquid crystals and several important liquid crystal devices are described. Ideas for practical experiments to illustrate the properties of liquid crystals and their operation in devices are also described. (Author/JN)
ERIC Educational Resources Information Center
Marroum, Renata-Maria
1996-01-01
Discusses the properties and classification of liquid crystals. Presents a simple experiment that illustrates the structure of liquid crystals and the differences between the various phases liquid crystals can assume. (JRH)
Alcazar Jorba, Daniel
2012-01-01
Liquid foams are dispersions of bubbles in a liquid. Bubbles are stabilized by foaming agents that position at the interface between the gas and the liquid. Most foaming agents, such as the commonly used sodium dodecylsulfate, ...
Skin adhesives; Tissue adhesive ... the cut is minor, a liquid bandage (liquid adhesive) can be used on the cut to close ... bandage is quick and painless to apply. Skin adhesives, or liquid bandages, seal the cut closed after ...
Liquid-liquid-solid transition in viscoelastic liquids
Zubelewicz, Aleksander
2013-01-01
Liquid-liquid-solid transitions (LLST) are known to occur in confined liquids, exist in supercooled liquids and emerge in liquids driven from equilibrium. Molecular dynamics (MD) simulations claim many successes in forecasting the phenomena. The transitions are also studied in the framework of thermodynamics based methods and minimalistic models. In here, the proposed approach is derived in the framework of continuum and includes spatial and temporal dynamic heterogeneities; the approach is meant to capture the material behavior at small scales. We conjecture that the liquid-like and solid-like behaviors are dissimilar enough for the two to be governed by different constitutive relations. In this way, we gain additional degree of freedom, which is found essential when predicting the transitional phenomena. As a result, we derive the LLST criteria for liquids in equilibrium, during steady flow and at transient conditions. Lastly, we forecast short-lived LLSTs in human blood during cardiac cycle. PMID:23429528
Liquid-gas phase transition in hypernuclei
NASA Astrophysics Data System (ADS)
Mallik, S.; Chaudhuri, G.
2015-05-01
The fragmentation of excited hypernuclear systems formed in heavy ion collisions has been described by the canonical thermodynamical model extended to three-component systems. The multiplicity distribution of the fragments has been analyzed in detail and it has been observed that the hyperons tend to get attached to the heavier fragments. Another important observation is the phase coexistence of the hyperons, a phenomenon which is linked to the liquid-gas phase transition in strange matter.
Liquid sloshing in a tilted cylindrical tank.
NASA Technical Reports Server (NTRS)
Dodge, F. T.; Garza, L. R.
1972-01-01
Two distinct fundamental modes are shown to exist for liquid sloshing in a tilted cylindrical tank. The 'long' mode is excited by tank motions parallel to the long axis of the elliptical free surface, the 'short' mode by tank motions perpendicular to it. Experiments show that the natural frequencies of both modes decrease as the tilt increases, and the slosh damping decreases markedly with increased tilt for the long mode.
Parametric Excitation of a DWSC
Lakhotia, Chandan
2011-08-08
Parametric excitation of the DWSC (Deep Water Stable Craneship) is studied in this thesis. It occurs for a system without any external forcing, when one of the coefficients in the equation of motion (EOM) modeling the system varies with time...
Claudius Gros; Kay Hamacher; Wolfgang Wenzel
2005-01-01
We investigate the momentum distribution function near the Mott-Hubbard transition in the one-dimensional t1-t2 Hubbard model (the zigzag Hubbard chain) with the density matrix renormalization group technique. We show that for strong interactions the Mott-Hubbard transition occurs between the metallic phase and an insulating dimerized phase with incommensurate spin excitations, suggesting a decoupling of magnetic and charge excitations not present
Non-Fermi liquids and the Wiedemann-Franz law
Mahajan, Raghu; Hartnoll, Sean A
2013-01-01
A general discussion of the ratio of thermal and electrical conductivities in non-Fermi liquid metals is given. In metals with sharp Drude peaks, the relevant physics is correctly organized around the slow relaxation of almost-conserved momenta. While in Fermi liquids both currents and momenta relax slowly, due to the weakness of interactions among low energy excitations, in strongly interacting non-Fermi liquids typically only momenta relax slowly. It follows that the conductivities of such non-Fermi liquids are obtained within a fundamentally different kinematics to Fermi liquids. Among these strongly interacting non-Fermi liquids we distinguish cases with only one almost-conserved momentum, which we term hydrodynamic metals, and with many patchwise almost-conserved momenta. For all these cases, we obtain universal expressions for the ratio of conductivities that violate the Wiedemann-Franz law. We further discuss the case in which long-lived `cold' quasiparticles, in general with unconventional scattering ...
Collisional excitation of interstellar formaldehyde
NASA Technical Reports Server (NTRS)
Green, S.; Garrison, B. J.; Lester, W. A., Jr.; Miller, W. H.
1978-01-01
Previous calculations for rates of excitation of ortho-H2CO by collisions with He have been extended to higher rotational levels and kinetic temperatures to 80 K. Rates for para-H2CO have also been computed. Pressure-broadening widths for several spectral lines have been obtained from these calculations and are found to agree with recent data within the experimental uncertainty of 10%. Excitation of formaldehyde by collisions with H2 molecules is also discussed.
Transport currents in Bose quantum liquids
Apaja, V.; Krotscheck, E.; Rimnac, A. [Institut fuer Theoretische Physik, Johannes Kepler Universitaet, A 4040 Linz (Austria); Zillich, R. E. [Fraunhofer ITWM, D-67663 Kaiserslautern (Germany)
2006-09-07
Until now, most of what has been said about excitations in quantum liquids has concerned the dynamic structure function, which is observable by means of neutron scattering. The dynamic structure function can be calculated using standard linear response theory. However, at this level one needs only transition densities <0{rho}n> or transition currents <0jn>, which are oscillatory in time and hence do not describe mass transport. In this work we go a step further and study transport currents in excited states,
LIFETIME SHORTENING FROM MICRO TO NANO IN COPPER DOPED CaS AT LIQUID NITROGEN TEMPERATURE
SUNIL KUMAR; N. K. VERMAa; S. K. CHAKARVARTIb; J. K. SHARMA
Copper doped Calcium sulphide phosphors having variable concentrations of killer impurities Fe, Co and Ni have been synthesized and then using laser excitation of samples for there photoluminescence behaviour, their decay-curve analysis has been done. Various strong emissions in these phosphors have been detected and the corresponding excited state lifetimes are measured at liquid nitrogen temperature. Studies have also been
NASA Technical Reports Server (NTRS)
Ludewig, Hans
1991-01-01
It is shown that the specific impulse varies with the square root of the temperature and inversely with the square root of the molecular weight of the propellant. Typical values for specific impulse corresponding to various rocket concepts are shown. The Liquid Annulus core concept consists of a fuel element which will be arranged in a moderator block. The advantages as seen for the system are: high specific impulse; structural material will all run at low temperature; and lower fission product inventory because of evaporation. It is felt that this concept is worth at least a first look because of the promise of very high specific impulse. Because of the low thrust, one would probably need a cluster of engines. This is not necessarily bad because there would be some redundancy, but because of the low thrust one might have to refuel while running. Depending on the fuel vaporization, material can be included in the uranium that is injected as one is running along.
Optoacoustic effects in absorbing liquids under the action of pulsed bessel light
NASA Astrophysics Data System (ADS)
Romanov, O. G.; Romanov, G. S.
2012-03-01
The excitation of acoustic oscillations in absorbing liquids exposed to pulsed Bessel light beams has been considered theoretically. Spatial profiles of refractive index diffraction patterns and the kinetics of their excitation and relaxation have been studied based on a numerical solution of continuous medium motion equations in a Lagrangian form and a heat-transfer equation and using the Lorentz-Lorenz formula. The conditions for optimal excitation of spatially localized acoustic pulses have been determined.
Resonant transfer excitation: Interference effects
Shafroth, S.M. [North Carolina Univ., Chapel Hill, NC (United States). Dept. of Physics and Astronomy; Benhenni, M. [North Carolina Univ., Chapel Hill, NC (United States). Dept. of Physics and Astronomy]|[Toulouse-3 Univ., 31 (France). Lab. de Decharges dans les Gaz; Swenson, J.K. [Oak Ridge National Lab., TN (United States)]|[Lawrence Livermore National Lab., CA (United States); Schulz, M. [Oak Ridge National Lab., TN (United States)]|[Missouri Univ., Rolla, MO (United States). Dept. of Physics; Giese, J.P.; Schone, H. [Oak Ridge National Lab., TN (United States)]|[Kansas State Univ., Manhattan, KS (United States). Dept. of Physics; Vane, C.R.; Dittner, P.F.; Datz, S. [Oak Ridge National Lab., TN (United States)
1991-12-31
Interference effects in RTE (Resonant Transfer Excitation) can be studied for low Z projectiles via Auger electrons emitted from highly ionized fast moving projectile ions following collisions with low Z targets. RTE in ion-atom collisions is closely related to dielectronic recombination. In the latter case which is of practical interest to the fusion power program an electron with the proper velocity incident on a highly charged ion is resonantly captured and simultaneously interacts with an inner shell electron to excite it, thus forming a doubly excited state which may decay predominantly by X-ray emission for higher Z ions or by Auger electron decay for lower Z ions. The resonant velocity is that of the Auger electron emitted by the ion in the doubly excited state in RTE the electrons to be captured are in low Z atomic (typically He) or Molecular (typically H{sub 2}) targets and the ions are produced by accelerators in highly charged states with the appropriate resonant velocity. The resonance is much broadened by the velocity distribution of the target electrons. Thus the resonance width as a function of projectile energy is determined by folding the Compton profile of the target electrons with the dielectronic recombination cross sections. A weaker effect and more speculative is Two Electron Transfer Excitation. Here one target electron excites the projectile 1s electron to the 2p shell for example and the other target electron is captured to an excited state of the projectile. This effect becomes more important at projectile energies higher than the energy where the RTE cross section has its maximum value. The electron--electron interaction has been beautifully demonstrated by Zouros et al. Finally, there might be interference with shakeup. This paper will present angular distribution measurements of Auger lines so that the effects of interference between these various processes can be studied.
Resonant transfer excitation: Interference effects
Shafroth, S.M. (North Carolina Univ., Chapel Hill, NC (United States). Dept. of Physics and Astronomy); Benhenni, M. (North Carolina Univ., Chapel Hill, NC (United States). Dept. of Physics and Astronomy Toulouse-3 Univ., 31 (France). Lab. de Decharges dans les Gaz); Swenson, J.K. (Oak Ridge National Lab., TN (United States) Lawrence Livermore National Lab., CA (United States)); Schulz, M. (Oak R
1991-01-01
Interference effects in RTE (Resonant Transfer Excitation) can be studied for low Z projectiles via Auger electrons emitted from highly ionized fast moving projectile ions following collisions with low Z targets. RTE in ion-atom collisions is closely related to dielectronic recombination. In the latter case which is of practical interest to the fusion power program an electron with the proper velocity incident on a highly charged ion is resonantly captured and simultaneously interacts with an inner shell electron to excite it, thus forming a doubly excited state which may decay predominantly by X-ray emission for higher Z ions or by Auger electron decay for lower Z ions. The resonant velocity is that of the Auger electron emitted by the ion in the doubly excited state in RTE the electrons to be captured are in low Z atomic (typically He) or Molecular (typically H{sub 2}) targets and the ions are produced by accelerators in highly charged states with the appropriate resonant velocity. The resonance is much broadened by the velocity distribution of the target electrons. Thus the resonance width as a function of projectile energy is determined by folding the Compton profile of the target electrons with the dielectronic recombination cross sections. A weaker effect and more speculative is Two Electron Transfer Excitation. Here one target electron excites the projectile 1s electron to the 2p shell for example and the other target electron is captured to an excited state of the projectile. This effect becomes more important at projectile energies higher than the energy where the RTE cross section has its maximum value. The electron--electron interaction has been beautifully demonstrated by Zouros et al. Finally, there might be interference with shakeup. This paper will present angular distribution measurements of Auger lines so that the effects of interference between these various processes can be studied.
Performance seeking control excitation mode
NASA Technical Reports Server (NTRS)
Schkolnik, Gerard
1995-01-01
Flight testing of the performance seeking control (PSC) excitation mode was successfully completed at NASA Dryden on the F-15 highly integrated digital electronic control (HIDEC) aircraft. Although the excitation mode was not one of the original objectives of the PSC program, it was rapidly prototyped and implemented into the architecture of the PSC algorithm, allowing valuable and timely research data to be gathered. The primary flight test objective was to investigate the feasibility of a future measurement-based performance optimization algorithm. This future algorithm, called AdAPT, which stands for adaptive aircraft performance technology, generates and applies excitation inputs to selected control effectors. Fourier transformations are used to convert measured response and control effector data into frequency domain models which are mapped into state space models using multiterm frequency matching. Formal optimization principles are applied to produce an integrated, performance optimal effector suite. The key technical challenge of the measurement-based approach is the identification of the gradient of the performance index to the selected control effector. This concern was addressed by the excitation mode flight test. The AdAPT feasibility study utilized the PSC excitation mode to apply separate sinusoidal excitation trims to the controls - one aircraft, inlet first ramp (cowl), and one engine, throat area. Aircraft control and response data were recorded using on-board instrumentation and analyzed post-flight. Sensor noise characteristics, axial acceleration performance gradients, and repeatability were determined. Results were compared to pilot comments to assess the ride quality. Flight test results indicate that performance gradients were identified at all flight conditions, sensor noise levels were acceptable at the frequencies of interest, and excitations were generally not sensed by the pilot.
Minimizing liquid contaminants in natural gas liquids
Brown, R.L. [Pall Industrial Process Filtration, East Hills, NY (United States); Wines, T.H. [Pall Scientific and Laboratory Services, Port Washington, NY (United States); Williamson, K.M. [Pall Process Equipment Development, Cortland, NY (United States)
1996-12-31
In processing natural gas liquids, significant contamination occurs with liquid dispersions and emulsions. Natural gas liquids (NGL) and liquid petroleum gas (LPG) streams are treated with caustic to remove residual organic sulfur compounds such as mercaptans and with amines to remove hydrogen sulfide. In both cases a liquid/liquid contactor is used. Significant amounts of the caustic or amine can be carried over into the product stream in process units that are running at rates above design capacity, are treating high sulfur feed stocks, or have other operational problems. The carried over liquid results in off-spec products, excessive loses of caustic or amine, and can cause operating problems in downstream processes. In addition, water is a significant contaminant which can cause LPG and natural gasoline to be off-specification. This paper discusses a new technique for separating very stable liquid dispersions of caustic, amine, or water from natural gas liquids using liquid/liquid cartridge coalescers constructed with specially formulated polymer and fluoropolymer medium with enhanced surface properties. In addition, factors influencing the coalescer mechanism will be discussed including interfacial tension, concentration of surface active compounds, steric repulsion, and electrostatic charge affects. Results from field tests, operating data from commercial installations, and economic benefits will also be presented.
Supporting Information for Excited State Interactions in Calix[4]arenePerylene Bisimide Dye
van Stokkum, Ivo
: Compounds oc2S1 , orefS2 and oPMIS3 were synthesized according to literature procedures, compound oS1 Supporting Information for Excited State Interactions in Calix[4]arenePerylene Bisimide Dye). High performance liquid chromatography (HPLC) was performed on SiO2 columns, normal phase (NP), with p
Jet cooled spectra of pyrrolobenzene and of pyrrolobenzonitrile: the nature of the excited states
Haas, Yehuda
multiphoton ionization (REMPI) excitation spectra of pyr- rolobenzene (PB) and pyrrolobenzonitrile (PBN) were.V. All rights reserved. 1. Introduction PB [1,2] and PBN [3,4] were recently studied in liquid solution) action spectra. In addition, fluo- rescence decay times were obtained. The results on PBN are compared
Transverse instabilities and pattern formation in two-beam-excited nonlinear optical
Bentley, Sean
higher intensity, whole-beam self-focusing of each beam begins to be observable, but interaction whole-beam self-focusing and small-scale filamenta- tion, and two-beam-excited self-diffraction spots instabilities that occur when two laser beams intersect in nonlinear optical liquids. Patterns that we observe
Pharos is designed for studies of fundamental excitations in condensed-matter systems. The
Pharos is designed for studies of fundamental excitations in condensed-matter systems° and 145°. Pharos can accommodate the full range of inelastic scattering experiments on liquid 10080 Phonon dispersion of Pb at room temperature as measured by Pharos. The intensity of phonon
Acoustic excitation of superharmonic capillary waves on a meniscus in a planar microgeometry
Attinger, Daniel
to micro- scopic oscillations of a cavitating bubble.1,2 For a linear and conservative system the response the subharmonic response of a liquid-gas interface excited by vertical oscillations: the re- sponse frequency at the junction between a microchannel and a chamber, in a micro- fluidic chip. We observe superharmonic
LIFETIME OF THE EXCITED STATE IN VIVO I. CHLOROPHYLL a IN ALGAE, AT ROOM
Govindjee
cruentum, and the blue-green alga Anacystis nidulans was measured by the phase- shift method under in the red alga Porphyridium, and 1.2 ±0.4 nsec in the blue-green alga Anacystis. Dmitrievsky et al. (2LIFETIME OF THE EXCITED STATE IN VIVO I. CHLOROPHYLL a IN ALGAE, AT ROOM AND AT LIQUID NITROGEN
Nishio Hirai; Henry Eyring
1958-01-01
The mechanisms for bulk viscosity are different between associated and nonassociated liquids. Here, a new mechanism for bulk viscosity is proposed from the standpoint of the hole theory of liquids and the rate process theory. This mechanism can explain the temperature and pressure dependencies of acoustic absorption for associated liquids and very viscous nonassociated liquids.
Liquidity and capital structure
Marc L. Lipson; Sandra Mortal
2009-01-01
We examine the relation between equity market liquidity and capital structure. We find that firms with more liquid equity have lower leverage and prefer equity financing when raising capital. For example, after sorting firms into size quintiles and then into liquidity quintiles, the average debt-to-asset ratio of the most liquid quintiles is about 38% while the average for the least
Ionic Liquids Database- (ILThermo)
National Institute of Standards and Technology Data Gateway
SRD 147 Ionic Liquids Database- (ILThermo) (Web, free access) IUPAC Ionic Liquids Database, ILThermo, is a free web research tool that allows users worldwide to access an up-to-date data collection from the publications on experimental investigations of thermodynamic, and transport properties of ionic liquids as well as binary and ternary mixtures containing ionic liquids.
Traveling Through Different Liquids
NSDL National Science Digital Library
2012-06-26
Learners observe and record what happens when they manipulate bottles containing a liquid (water or corn syrup) and one or more objects (screw, nail, paper clip). They should observe differences in how quickly the objects fall in the different liquids. This lesson builds on what learners have studied in previous lessons, Exploring Liquids and Exploring How Liquids Behave.
Nollmann, Marcelo
results with the mean-field Maier-Saupe theory of the nematic state are presented, and a model is proposedPhotobleaching and reorientational dynamics of dyes in a nematic liquid crystal M. No¨llmann and D Received 25 August 1998 The polarized fluorescence of excited dyes in a prototype nematic liquid crystal
John Arthur McLees, Jr. Vapor-Liquid Equilibrium of Monoethanolamine/Piperazine/Water at
Rochelle, Gary T.
Copyright by John Arthur McLees, Jr. 2006 #12;Vapor-Liquid Equilibrium of Monoethanolamine/Piperazine/Water in Engineering The University of Texas at Austin May, 2006 #12;Vapor-Liquid Equilibrium of Monoethanolamine/Piperazine/Water games, and road trips that I am very excited to be staying here in Austin to watch him progress through
Spectral line shifts of alkali atoms in liquid helium: a relativistic density functional approach
J. Anton; P. K. Mukherjee; B. Fricke; S. Fritzsche
2007-01-01
Excitation line shifts of the principal resonance transitions in alkali atoms sodium and cesium embedded inside the liquid helium environment have been calculated using four-component relativistic density functional theory. The effect of the liquid helium environment is assumed to be represented by a cluster of 14 atoms surrounding the central alkali atom. The estimated blue shift of the principal resonance
Modeling excitable systems: Reentrant tachycardia
NASA Astrophysics Data System (ADS)
Lancaster, Jarrett L.; Hellen, Edward H.; Leise, Esther M.
2010-01-01
Excitable membranes are an important type of nonlinear dynamical system, and their study can be used to provide a connection between physical and biological circuits. We discuss two models of excitable membranes important in cardiac and neural tissues. One model is based on the Fitzhugh-Nagumo equations, and the other is based on a three-transistor excitable circuit. We construct a circuit that simulates reentrant tachycardia and its treatment by surgical ablation. This project is appropriate for advanced undergraduates as a laboratory capstone project or as a senior thesis or honors project and can also be a collaborative project, with one student responsible for the computational predictions and another for the circuit construction and measurements.
NSDL National Science Digital Library
Sharon Janulaw
2010-01-01
Learners apply their knowledge from a previous study to identify different liquids--water, corn syrup, and vegetable oil. They also investigate combinations of liquids, two at a time, to see how they interact. This is meant as a follow-up lesson to the related activity, Exploring Liquids. As an extension, learners can continue their study of these liquids in the lesson, Traveling Through Different Liquids.
Sloshing response in a tank containing two liquids
Tang, Y.; Ma, D.C.; Chang, Y.W.
1991-01-01
A study on the sloshing response in a tank containing two different liquids under seismic excitation is presented. Both analytical and numerical (FEM) methods are employed in the analysis. The results obtained by the two methods are in good agreement. The response quantities examined include the sloshing wave height, the natural frequencies of the sloshing motion, and the vertical displacement at the interface of the two liquids. It is shown that the maximum sloshing wave height may increase significantly, and the fundamental period of the sloshing motion is longer than that in an identical tank containing only one liquid. 10 refs., 12 figs.
Liquid crystal fibers of bent-core molecules.
Jákli, Antal; Krüerke, Daniel; Nair, Geetha G
2003-05-01
Although the liquid-crystal research is well established in science, there are newly emerging exciting systems, that deserve extensive basic studies. One of these areas is the research of the bent-shaped molecules (so-called "banana liquid crystals"), which have delicate chirality and polarity properties. In this paper we show that these materials also have very unusual rheological features, such as the formation of stable fluid fibers and bridges. Under electric fields, these objects present striking mechanical effects, such as horizontal and transversal vibrations. Studies indicate that the research of banana-liquid-crystal fibers may lead to new type of artificial muscle systems. PMID:12786159
NASA Technical Reports Server (NTRS)
Hung, R. J.; Shyu, K. L.
1992-01-01
The objective of the cryogenic fluid management of the spacecraft propulsion system is to develop the technology necessary for acquisition or positioning of liquid and vapor within a tank in reduced gravity to enable liquid outflow or vapor venting. The requirement to settle or to position liquid fuel over the outlet end of the spacecraft propellant tank prior to main engine restart poses a microgravity fluid behavior problem. The purpose of the present study is to investigate the stability of the most efficient technique for propellant resettling through the minimization of propellant usage and weight penalties. In this study slosh wave excitation induced by the resettling flow field activated by 0.1 Hz low frequency, impulsive reverse gravity acceleration, during reorientation with the initiation of geyser for liquid fill levels of 30, 50, 65, 70 and 80 percent, have been studied. Characteristics of slosh waves with various frequencies excited are discussed. Slosh wave excitation shift the fluid mass distribution in the container which impose time dependent variations in spacecraft moment of inertia. This information is important for the spacecraft control during the course of liquid reorientation.
Collective hypersonic excitations in strongly multiple scattering colloids.
Still, T; Gantzounis, G; Kiefer, D; Hellmann, G; Sainidou, R; Fytas, G; Stefanou, N
2011-04-29
Unprecedented low-dispersion high-frequency acoustic excitations are observed in dense suspensions of elastically hard colloids. The experimental phononic band structure for SiO(2) particles with different sizes and volume fractions is well represented by rigorous full-elastodynamic multiple-scattering calculations. The slow phonons, which do not relate to particle resonances, are localized in the surrounding liquid medium and stem from coherent multiple scattering that becomes strong in the close-packing regime. Such rich phonon-matter interactions in nanostructures, being still unexplored, can open new opportunities in phononics. PMID:21635048
Autoresonant excitation of antiproton plasmas.
Andresen, G B; Ashkezari, M D; Baquero-Ruiz, M; Bertsche, W; Bowe, P D; Butler, E; Carpenter, P T; Cesar, C L; Chapman, S; Charlton, M; Fajans, J; Friesen, T; Fujiwara, M C; Gill, D R; Hangst, J S; Hardy, W N; Hayden, M E; Humphries, A J; Hurt, J L; Hydomako, R; Jonsell, S; Madsen, N; Menary, S; Nolan, P; Olchanski, K; Olin, A; Povilus, A; Pusa, P; Robicheaux, F; Sarid, E; Silveira, D M; So, C; Storey, J W; Thompson, R I; van der Werf, D P; Wurtele, J S; Yamazaki, Y
2011-01-14
We demonstrate controllable excitation of the center-of-mass longitudinal motion of a thermal antiproton plasma using a swept-frequency autoresonant drive. When the plasma is cold, dense, and highly collective in nature, we observe that the entire system behaves as a single-particle nonlinear oscillator, as predicted by a recent theory. In contrast, only a fraction of the antiprotons in a warm plasma can be similarly excited. Antihydrogen was produced and trapped by using this technique to drive antiprotons into a positron plasma, thereby initiating atomic recombination. PMID:21405235
Dynamics of Elastic Excitable Media
Julyan H. E. Cartwright; Victor M. Eguiluz; Emilio Hernandez-Garcia; Oreste Piro
1999-05-20
The Burridge-Knopoff model of earthquake faults with viscous friction is equivalent to a van der Pol-FitzHugh-Nagumo model for excitable media with elastic coupling. The lubricated creep-slip friction law we use in the Burridge-Knopoff model describes the frictional sliding dynamics of a range of real materials. Low-dimensional structures including synchronized oscillations and propagating fronts are dominant, in agreement with the results of laboratory friction experiments. Here we explore the dynamics of fronts in elastic excitable media.
An incompressible state of a photo-excited electron gas
Chepelianskii, Alexei D.; Watanabe, Masamitsu; Nasyedkin, Kostyantyn; Kono, Kimitoshi; Konstantinov, Denis
2015-01-01
Two-dimensional electrons in a magnetic field can form new states of matter characterized by topological properties and strong electronic correlations as displayed in the integer and fractional quantum Hall states. In these states, the electron liquid displays several spectacular characteristics, which manifest themselves in transport experiments with the quantization of the Hall resistance and a vanishing longitudinal conductivity or in thermodynamic equilibrium when the electron fluid becomes incompressible. Several experiments have reported that dissipationless transport can be achieved even at weak, non-quantizing magnetic fields when the electrons absorb photons at specific energies related to their cyclotron frequency. Here we perform compressibility measurements on electrons on liquid helium demonstrating the formation of an incompressible electronic state under these resonant excitation conditions. This new state provides a striking example of irradiation-induced self-organization in a quantum system. PMID:26007282
An incompressible state of a photo-excited electron gas.
Chepelianskii, Alexei D; Watanabe, Masamitsu; Nasyedkin, Kostyantyn; Kono, Kimitoshi; Konstantinov, Denis
2015-01-01
Two-dimensional electrons in a magnetic field can form new states of matter characterized by topological properties and strong electronic correlations as displayed in the integer and fractional quantum Hall states. In these states, the electron liquid displays several spectacular characteristics, which manifest themselves in transport experiments with the quantization of the Hall resistance and a vanishing longitudinal conductivity or in thermodynamic equilibrium when the electron fluid becomes incompressible. Several experiments have reported that dissipationless transport can be achieved even at weak, non-quantizing magnetic fields when the electrons absorb photons at specific energies related to their cyclotron frequency. Here we perform compressibility measurements on electrons on liquid helium demonstrating the formation of an incompressible electronic state under these resonant excitation conditions. This new state provides a striking example of irradiation-induced self-organization in a quantum system. PMID:26007282
Low-frequency in stability in liquid - propellant rocket motors
K. S. Kolesnikov
1965-01-01
A detailed analysis of the simultaneous action Of both excitation mechanisms was given in monograph [4]. Analysis of the stability of operation of a rocket motor, allowing for compressibility of the liquid in the feed line, for the simplest monopropellant system, shows that the critical delay time depends on the length of the line and decreases with the increase in
Nonlinear modeling of liquid sloshing in a moving rectangular tank
M. Serdar Celebi; Hakan Akyildiz
2002-01-01
A nonlinear liquid sloshing inside a partially filled rectangular tank has been investigated. The fluid is assumed to be homogeneous, isotropic, viscous, Newtonian and exhibit only limited compressibility. The tank is forced to move harmonically along a vertical curve with rolling motion to simulate the actual tank excitation. The volume of fluid technique is used to track the free surface.
AN EFFICIENT LIQUID SLOSHING DAMPER FOR VIBRATION CONTROL
V. J. MODI; S. R. MUNSHI
1998-01-01
The next generation of tall structures are being designed to be lighter and more flxible, making them susceptible to wind, ocean waves and earthquake type of excitations. One approach to vibration control of such systems is through energy dissipation using a liquid sloshing damper. Such dampers are already in use for vibration control of tall structures in Japan and Australia.
Huang, Jung Y; Li, Liu S
2011-10-20
A liquid crystal polymer (LCP) self-assembled on a photoirradiated substrate can modify the viscoelastic response of liquid crystal medium on the substrate. Sum-frequency vibrational spectroscopy shows that the phenyl groups of LCP are oriented epitaxially with layer thickness and an in-plane alignment order much higher than that at the photoirradiated surface can be yielded. The liquid crystal molecules confined between the LCP-coated substrates reveals a stronger correlation among the thermally excited fluctuation modes. Our finding can be used to tailor the boundary forces on alignment substrates and to optimize the device performance. PMID:21902209
Edwin Langmann
2010-04-14
A detailed derivation of a two dimensional (2D) low energy effective model for spinless fermions on a square lattice with local interactions is given. This derivation utilizes a particular continuum limit that is justified by physical arguments. It is shown that the effective model thus obtained can be treated by exact bosonization methods. It is also discussed how this effective model can be used to obtain physical information about the corresponding lattice fermion system.
Integrated continuous microfluidic liquid-liquid extraction.
Kralj, Jason G; Sahoo, Hemantkumar R; Jensen, Klavs F
2007-02-01
We describe continuous flow liquid-liquid phase separation in microfluidic devices based on capillary forces and selective wetting surfaces. Effective liquid-liquid phase separation is achieved by using a thin porous fluoropolymer membrane that selectively wets non-aqueous solvents, has average pore sizes in the 0.1-1 microm range, and has a high pore density for high separation throughput. Pressure drops throughout the microfluidic network are modelled and operating regimes for the membrane phase separator are determined based on hydrodynamic pressure drops and capillary forces. A microfluidic extraction device integrating mixing and phase separation is realized by using silicon micromachining. Modeling of the phase separator establishes the operating limits. The device is capable of completely separating several organic-aqueous and fluorous-aqueous liquid-liquid systems, even with high fractions of partially miscible compounds. In each case, extraction is equivalent to one equilibrium extraction stage. PMID:17268629
Tuning the Pitch of a Wine Glass by Playing with the Liquid inside
ERIC Educational Resources Information Center
Courtois, Matthieu; Guirao, Boris; Fort, Emmanuel
2008-01-01
It is well known that the pitch of the sound produced by an excited glass shell can be tuned by adding some liquid in it. In this paper, it will be proved that the distribution of the liquid inside the shell plays a crucial role in this frequency shift. Thus it provides another way to tune the pitch of the sound by modifying the liquid…
Mass transfer enhancement by gravity waves at a liquid–vapour interface
S. P. Das; E. J. Hopfinger
2009-01-01
Experimental results on mass transfer enhancement by large amplitude gravity waves at a liquid–gas\\/vapour interface are presented. The waves are sub-harmonically excited in a circular cylinder that is partially filled with liquid, by oscillating the cylinder in the direction normal to the liquid surface. The lowest asymmetric sloshing mode (1,1) as well as the axisymmetric mode (0,1) are considered in
Hydrodynamic response of viscous fluids under seismic excitation
Ma, D.C.
1993-08-01
Hydrodynamic response of liquid-tank systems, such as reactor vessels, spent-fuel pools and liquid storage tanks have been studied extensively in the last decade (Chang et al. 1988; Ma et al. 1991). However, most of the studies are conducted with the assumption of an inviscid fluid. In recent years, the hydrodynamic response of viscous fluids has received increasing attention in high level waste storage tanks containing viscous waste material. This paper presents a numerical study on the hydrodynamic response of viscous fluids in a large 2-D fluid-tank system under seismic excitation. Hydrodynamic responses (i.e. sloshing wave height, fluid pressures, shear stress, etc.) are calculated for a fluid with various viscosities. Four fluid viscosities are considered. They are 1 cp, 120 cp, 1,000 cp and 12,000 cp (1 cp = 1.45 {times} 10{sup {minus}7} lb-sec/in{sup 2}). Note that the liquid sodium of the Liquid-Metal Reactor (LMR) reactor has a viscosity of 1.38 {times} 10{sup {minus}5} lb-sec/in{sup 2} (about 95 cp) at an operational temperature of 900{degree}F. Section 2 describes the pertinent features of the mathematical model. In Section 3, the fundamental sloshing phenomena of viscous fluid are examined. Sloshing wave height and shear stress for fluid with different viscosities are compared. The conclusions are given in Section 4.
Communicating the Excitement of Science
Michael Turner
2010-01-08
In this talk (which will include some exciting science) I will discuss some lessons I have learned about communicating science to scientists (in my own field and others), students, the public, the press, and policy makers in giving 500+ colloquia and seminars, 300+ public lectures and many informal presentations (including cocktail parties).
Cardiac excitation–contraction coupling
Donald M. Bers
2002-01-01
Of the ions involved in the intricate workings of the heart, calcium is considered perhaps the most important. It is crucial to the very process that enables the chambers of the heart to contract and relax, a process called excitation–contraction coupling. It is important to understand in quantitative detail exactly how calcium is moved around the various organelles of the
Multi-photon excitation microscopy
Alberto Diaspro; Paolo Bianchini; Giuseppe Vicidomini; Mario Faretta; Paola Ramoino; Cesare Usai
2006-01-01
Multi-photon excitation (MPE) microscopy plays a growing role among microscopical techniques utilized for studying biological matter. In conjunction with confocal microscopy it can be considered the imaging workhorse of life science laboratories. Its roots can be found in a fundamental work written by Maria Goeppert Mayer more than 70 years ago. Nowadays, 2PE and MPE microscopes are expected to increase
Pseudorandom selective excitation in NMR
NASA Astrophysics Data System (ADS)
Walls, Jamie D.; Coomes, Alexandra
2011-09-01
In this work, average Hamiltonian theory is used to study selective excitation under a series of small flip-angle ?-pulses ? ? {?}/{3} applied either periodically [corresponding to the DANTE pulse sequence] or aperiodically to a spin-1/2 system. First, an average Hamiltonian description of the DANTE pulse sequence is developed that is valid for frequencies either at or very far from integer multiples of {1}/{?}, where ? is the interpulse delay. For aperiodic excitation, a single resonance, ?sel, can be selectively excited if the ?-pulse phases are modulated in concert with the interpulse delays. The conditions where average Hamiltonian theory can be accurately applied to describe the dynamics under aperiodic selective pulses, which are referred to as pseudorandom-DANTE or p-DANTE sequences, are similar to those found for the DANTE sequence. Signal averaging over different p-DANTE sequences improves the apparent selectivity at ?sel by reducing the excitations at other frequencies. Experimental demonstrations of p-DANTE sequences and comparisons with the theory are presented.
Pseudorandom Selective Excitation in NMR
Jamie D. Walls; Alexandra Coomes
2010-07-20
In this work, average Hamiltonian theory is used to study selective excitation in a spin-1/2 system evolving under a series of small flip-angle $\\theta-$pulses $(\\theta\\ll 1)$ that are applied either periodically [which corresponds to the DANTE pulse sequence] or aperiodically. First, an average Hamiltonian description of the DANTE pulse sequence is developed; such a description is determined to be valid either at or very far from the DANTE resonance frequencies, which are simply integer multiples of the inverse of the interpulse delay. For aperiodic excitation schemes where the interpulse delays are chosen pseudorandomly, a single resonance can be selectively excited if the $\\theta$-pulses' phases are modulated in concert with the time delays. Such a selective pulse is termed a pseudorandom-DANTE or p-DANTE sequence, and the conditions in which an average Hamiltonian description of p-DANTE is found to be similar to that found for the DANTE sequence. It is also shown that averaging over different p-DANTE sequences that are selective for the same resonance can help reduce excitations at frequencies away from the resonance frequency, thereby improving the apparent selectivity of the p-DANTE sequences. Finally, experimental demonstrations of p-DANTE sequences and comparisons with theory are presented.
Perceptual Load Alters Visual Excitability
ERIC Educational Resources Information Center
Carmel, David; Thorne, Jeremy D.; Rees, Geraint; Lavie, Nilli
2011-01-01
Increasing perceptual load reduces the processing of visual stimuli outside the focus of attention, but the mechanism underlying these effects remains unclear. Here we tested an account attributing the effects of perceptual load to modulations of visual cortex excitability. In contrast to stimulus competition accounts, which propose that load…
Materials modification by electronic excitation
NASA Astrophysics Data System (ADS)
Stoneham, A. M.; Itoh, Noriaki
2000-12-01
Electronic excitation by lasers or electron beams can modify the properties of materials. The changes are not just due to heat, nor do they result from the well-known collision dynamics of much radiation damage. Everyday examples of modification by electronic excitation include photography, and photochromics (such as sunglasses) which change colour. In the last few years it has become clear that excitation can offer novel types of modification, with better-controlled changes. The field has evolved through a mix of basic science, of new laser and electron beam tools, and of new needs from microelectronics, photonics and nanotechnology. Underlying this development are some common themes which integrate the basic science and its applications. These include especially the ideas of energy localisation and charge localisation. There are detailed comparisons of experiment and theory for halides, but there is a wealth of information for other materials. From this, we identify ways to connect understanding to technological needs, like selective removal of material, controlled changes, altering the balance between process steps, and possibilities of quantum control. The field is reviewed in full in our recent book [N. Itoh, A.M. Stoneham, Materials Modification by Electronic Excitation, Cambridge University Press, Cambridge, 2000].
Fractionalization of itinerant anyons in one dimensional chains
Didier Poilblanc; Matthias Troyer; Eddy Ardonne; Parsa Bonderson
2011-12-27
We construct models of interacting itinerant non-Abelian anyons moving along one-dimensional chains, focusing in particular on itinerant Ising anyon chains, and derive effective anyonic t-J models for the low energy sectors. Solving these models by exact diagonalization, we find a fractionalization of the anyons into charge and (non-Abelian) anyonic degrees of freedom -- a generalization of spin-charge separation of electrons which occurs in Luttinger liquids. A detailed description of the excitation spectrum by combining spectra for charge and anyonic sectors requires a subtle coupling between charge and anyonic excitations at the microscopic level (which we also find to be present in Luttinger liquids), despite the macroscopic fractionalization.
Electrical control and interaction effects of the RKKY interaction in helical liquids
NASA Astrophysics Data System (ADS)
Lee, Yu-Wen; Lee, Yu-Li
2015-06-01
We study the RKKY interaction mediated by the helical edge states of a quantum spin Hall insulator in the presence of the Rashba spin-orbital coupling induced by an external electric field and the electron-electron interaction. We show that in the presence of the Rashba coupling, the RKKY interaction induced by the helical edge states contains not only the Heisenberg-like and the Dzyaloshinskii-Moria terms, but also the nematic-type term that is not present in the absence of the Rashba coupling. Moreover, the range functions depend on the strength of the Rashba coupling. We also show that the electron-electron interaction changes the strength of the RKKY interaction by modifying the power of the 1 /|x | dependence of the range functions. In particular, by varying the strength of the interaction or the Rashba coupling, there is an (impurity) quantum phase transition involving the sign change of the RKKY interaction at the value of the Luttinger liquid parameter K =1 /2 . Since both the strength of the Rashba coupling and the chemical potential of the helical edge states are electrically controllable by external gate voltages, our results not only shed light on the nature of magnetic impurity correlations in the edge of a two-dimensional topological insulator, but also pave a way to manipulate the qubits in quantum computing.