Characteristic features of anharmonic effects in the lattice dynamics of fcc metalsThe dispersion in the entire Brillouin zone and the temperature dependence (right up to the melting temperature) of the anharmonic frequency shift and phonon damping in a number of fcc metals is…M. I. Katsnelson, A. V. Trefilov, K. Yu. Khromov·Jun 13, 2000SaveLearn
CPA density of states and conductivity in a double-exchange system containing impuritiesWe study density of states and conductivity of the doped double-exchange system, treating interaction of charge carriers both with the localized spins and with the impurities in the coherent…Mark Auslender, Eugene Kogan·Jun 11, 2000SaveLearn
Stabilizing an Attractive Bose-Einstein Condensate by Driving a Surface Collective ModeBose-Einstein condensates of 7Li have been limited in number due to attractive interatomic interactions. Beyond this number, the condensate undergoes collective collapse. We study theoretically…Arjendu K. Pattanayak, Arnaldo Gammal, Charles A. Sackett et al.·Jun 8, 2000SaveLearn
Spectral Statistics of the Two-Body Random Ensemble RevisitedUsing longer spectra we re-analyze spectral properties of the two-body random ensemble studied thirty years ago. At the center of the spectra the old results are largely confirmed, and we show that…J. Flores, M. Horoi, M. Mueller et al.·Jun 8, 2000SaveLearn
Superradiant light scattering and grating formation in cold atomic vapoursA semi-classical theory of coherent light scattering from an elongated sample of cold atoms exposed to an off-resonant laser beam is presented. The model, which is a direct extension of that of the…R. Bonifacio, B. W. J. McNeil, N. Piovella et al.·Jun 8, 2000SaveLearn
Thermodynamic properties of confined interacting Bose gases - a renormalization group approachA renormalization group method is developed with which thermodynamic properties of a weakly interacting, confined Bose gas can be investigated. Thereby effects originating from a confining potential…G. Alber·Jun 8, 2000SaveLearn
Motion of an object through a dilute quantum fluidWe simulate the motion of a massive object through a dilute Bose-Einstein condensate by numerical solution of the non-linear Schrödinger equation coupled to an equation of motion for the object.…T. Winiecki, C. S. Adams·Jun 8, 2000SaveLearn
Evolutionary minority game with heterogeneous strategy distributionWe present detailed numerical results for a modified form of the so-called Minority Game, which provides a simplified model of a competitive market. Each agent has a limited set of strategies, and…T. S. Lo, S. W. Lim, P. M. Hui et al.·Jun 8, 2000SaveLearn
Strong Confinement and Oscillations in Two-Component Bose-Einstein CondensatesWe present a new model of BEC dynamics based on strong confinement near the ground state. The model predicts oscillations in a two-component condensate, based on interference of non-spreading wave…Q-Han Park, J. H. Eberly·Jun 7, 2000SaveLearn
Probing Bose-Einstein Condensation of Excitons with Electromagnetic RadiationWe examine the absorption spectrum of electromagnetic radiation from excitons, where an exciton in the 1s state absorbs a photon and makes a transition to the 2p state. We demonstrate that the…K. Johnsen, G. M. Kavoulakis·Jun 7, 2000SaveLearn
Fine structure of excitons in a quantum well in the presence of a nonhomogeneous magnetic fieldThe trapping of excitons in a semiconductor quantum well due to a circular symmetric nonhomogeneous magnetic field is studied. The effect of the spin state of the exciton on its trapping energy is…J. A. K. Freire, F. M. Peeters, A. Matulis et al.·Jun 6, 2000SaveLearn
Renormalization of pinned elastic systems: how does it work beyond one loop ?We study the field theories for pinned elastic systems at equilibrium and at depinning. Their β-functions differ to two loops by novel ``anomalous'' terms. At equilibrium we find a…Pascal Chauve, Pierre Le Doussal, Kay Wiese·Jun 4, 2000SaveLearn
Exact renormalization group and applications to disordered problems: part IWe develop a systematic multi-local expansion of the Polchinski-Wilson exact renormalization group (ERG) equation. Integrating out explicitly the non local interactions, we reduce the ERG equation…Pascal Chauve, Pierre Le Doussal·Jun 4, 2000SaveLearn
Spin bath-mediated decoherence in superconductorsWe consider a SQUID tunneling between 2 nearly degenerate flux states. Decoherence caused by paramagnetic and nuclear spins in the low-T limit is shown to be much stronger than that from electronic…Nikolay Prokof'ev, Philip Stamp·Jun 4, 2000SaveLearn
Atomic scale engines: Cars and wheelsWe introduce a new approach to build microscopic engines on the atomic scale that move translationally or rotationally and can perform useful functions such as pulling of a cargo. Characteristic of…Markus Porto, Michael Urbakh, Joseph Klafter·Jun 4, 2000SaveLearn
Molecular motor that never steps backwardsWe investigate the dynamics of a classical particle in a one-dimensional two-wave potential composed of two periodic potentials, that are time-independent and of the same amplitude and periodicity.…Markus Porto, Michael Urbakh, Joseph Klafter·Jun 4, 2000SaveLearn
Reading the three-dimensional structure of a protein from its amino acid sequenceWhile all the information required for the folding of a protein is contained in its amino acid sequence, one has not yet learnt how to extract this information so as to predict the detailed,…R. A. Broglia, G. Tiana·Jun 3, 2000SaveLearn
Squeezed CondensatesWe analyse the atomic state obtained by photo-dissociation of a molecular Bose-Einstein-condensate. This process is equivalent to down-conversion in quantum optics where it is responsible for…Uffe V. Poulsen, Klaus Molmer·Jun 2, 2000SaveLearn
Two-dimensional dilute Bose gas in the normal phaseWe consider a two-dimensional dilute Bose gas above its superfluid transition temperature. We show that the t-matrix approximation corresponds to the leading set of diagrams in the dilute limit,…P. Pieri, G. C. Strinati, I. Tifrea·Jun 1, 2000SaveLearn
Non-spiky density of states of an icosahedral quasicrystalThe density of states of the ideal three-dimensional Penrose tiling, a quasicrystalline model, is calculated with a resolution of 10 meV. It is not spiky. This falsifies theoretical predictions so…E. S. Zijlstra, T. Janssen·Jun 1, 2000SaveLearn
Localization of acoustic waves in 1D random liquid mediaWe study acoustic propagation in one dimensional water ducts containing many air-filled blocks. The acoustic band structures for the periodic arrangements of the blocks is calculated, whereas the…Pi-Gang Luan, Zhen Ye·Jun 1, 2000SaveLearn
Inertial effects in three dimensional spinodal decomposition of a symmetric binary fluid mixture: A lattice Boltzmann studyThe late-stage demixing following spinodal decomposition of a three-dimensional symmetric binary fluid mixture is studied numerically, using a thermodynamicaly consistent lattice Boltzmann method. We…V. M. Kendon, M. E. Cates, J-C. Desplat et al.·Jun 1, 2000SaveLearn
Atom loss and the formation of a molecular Bose-Einstein condensate by Feshbach resonanceIn experiments conducted recently at MIT on Na Bose-Einstein condensates [S. Inouye et al, Nature 392, 151 (1998); J. Stenger et al, Phys. Rev. Lett. 82, 2422 (1999)], large loss rates were observed…V. A. Yurovsky, A. Ben-Reuven, P. S. Julienne et al.·Jun 1, 2000SaveLearn
Similarity transformation in one-dimensional reaction-diffusion systems; voting model as an exampleThe exact solution for a system with two-particle annihilation and decoagulation has been studied. The spectrum of the Hamiltonian of the system is found. It is shown that the steady state is…Amir Aghamohammadi, Mohammad Khorrami·May 31, 2000SaveLearn
An Efficient and Robust Technique for Achieving Self Consistency in Electronic Structure CalculationsPulay's Residual Metric Minimization (RMM) method is one of the standard techniques for achieving self consistency in ab initio electronic structure calculations. We describe a reformulation of…D. R. Bowler, M. J. Gillan·May 30, 2000SaveLearn