BoseEinsteincondensed systems in random potentials
Abstract
The properties of systems with BoseEinstein condensate in external timeindependent random potentials are investigated in the frame of a selfconsistent stochastic meanfield approximation. General considerations are presented, which are valid for finite temperatures, arbitrary strengths of the interaction potential, and for arbitrarily strong disorder potentials. The special case of a spatially uncorrelated random field is then treated in more detail. It is shown that the system consists of three components, condensed particles, uncondensed particles, and a glassy density fraction, but that the pure Bose glass phase with only a glassy density does not appear. The theory predicts a firstorder phase transition for increasing disorder parameter, where the condensate fraction and the superfluid fraction simultaneously jump to zero. The influence of disorder on the groundstate energy, the stability conditions, the compressibility, the structure factor, and the sound velocity are analyzed. The uniform ideal condensed gas is shown to be always stochastically unstable, in the sense that an infinitesimally weak disorder destroys the BoseEinstein condensate, returning the system to the normal state; but the uniform Bosecondensed system with finite repulsive interactions becomes stochastically stable and exists in a finite interval of the disorder parameter.
 Authors:
 Fachbereich Physik, Universitaet DuisburgEssen, 47048 Duisburg (Germany)
 (Russian Federation)
 Publication Date:
 OSTI Identifier:
 20982170
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevA.75.023619; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; APPROXIMATIONS; BOSEEINSTEIN CONDENSATION; COMPRESSIBILITY; CONDENSATES; DENSITY; GROUND STATES; INTERACTIONS; MEANFIELD THEORY; PHASE TRANSFORMATIONS; POTENTIALS; RANDOMNESS; SOUND WAVES; STABILITY; STOCHASTIC PROCESSES; STRUCTURE FACTORS; SUPERFLUIDITY; VELOCITY
Citation Formats
Yukalov, V. I., Bogolubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna 141980, and Graham, R. BoseEinsteincondensed systems in random potentials. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVA.75.023619.
Yukalov, V. I., Bogolubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna 141980, & Graham, R. BoseEinsteincondensed systems in random potentials. United States. doi:10.1103/PHYSREVA.75.023619.
Yukalov, V. I., Bogolubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna 141980, and Graham, R. Thu .
"BoseEinsteincondensed systems in random potentials". United States.
doi:10.1103/PHYSREVA.75.023619.
@article{osti_20982170,
title = {BoseEinsteincondensed systems in random potentials},
author = {Yukalov, V. I. and Bogolubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna 141980 and Graham, R.},
abstractNote = {The properties of systems with BoseEinstein condensate in external timeindependent random potentials are investigated in the frame of a selfconsistent stochastic meanfield approximation. General considerations are presented, which are valid for finite temperatures, arbitrary strengths of the interaction potential, and for arbitrarily strong disorder potentials. The special case of a spatially uncorrelated random field is then treated in more detail. It is shown that the system consists of three components, condensed particles, uncondensed particles, and a glassy density fraction, but that the pure Bose glass phase with only a glassy density does not appear. The theory predicts a firstorder phase transition for increasing disorder parameter, where the condensate fraction and the superfluid fraction simultaneously jump to zero. The influence of disorder on the groundstate energy, the stability conditions, the compressibility, the structure factor, and the sound velocity are analyzed. The uniform ideal condensed gas is shown to be always stochastically unstable, in the sense that an infinitesimally weak disorder destroys the BoseEinstein condensate, returning the system to the normal state; but the uniform Bosecondensed system with finite repulsive interactions becomes stochastically stable and exists in a finite interval of the disorder parameter.},
doi = {10.1103/PHYSREVA.75.023619},
journal = {Physical Review. A},
number = 2,
volume = 75,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}

BoseEinsteincondensed gases in external spatially random potentials are considered in the frame of a stochastic selfconsistent meanfield approach. This method permits the treatment of the system properties for the whole range of the interaction strength, from zero to infinity, as well as for arbitrarily strong disorder. Besides a condensate and superfluid density, a glassy number density due to a spatially inhomogeneous component of the condensate occurs. For very weak interactions and sufficiently strong disorder, the superfluid fraction can become smaller than the condensate fraction, while at relatively strong interactions, the superfluid fraction is larger than the condensate fraction for anymore »

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