Hydrodynamic modes of a onedimensional trapped Bose gas
Abstract
We consider two regimes where a trapped Bose gas behaves as a onedimensional (1D) system. In the first one the Bose gas is microscopically described by 3D meanfield theory, but the trap is so elongated that it behaves as a 1D gas with respect to lowfrequency collective modes. In the second regime we assume that the 1D gas is truly 1D and that it is properly described by the LiebLiniger model. In both regimes we find the frequency of the lowest compressional mode by solving the hydrodynamic equations. This is done by making use of a method which allows us to find analytical or quasianalytical solutions of these equations for a large class of models approaching very closely the actual equation of state of the Bose gas. We find an excellent agreement with the recent results of Menotti and Stringari obtained from a sumrule approach.
 Authors:
 Laboratoire Kastler Brossel, Ecole Normale Superieure, 24 rue Lhomond, 75231 Paris Cedex 05 (France)
 (France)
 Publication Date:
 OSTI Identifier:
 20640373
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 68; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevA.68.043610; (c) 2003 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 74 ATOMIC AND MOLECULAR PHYSICS; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BOSEEINSTEIN CONDENSATION; BOSEEINSTEIN GAS; EQUATIONS OF STATE; HYDRODYNAMICS; MATHEMATICAL SOLUTIONS; MEANFIELD THEORY; ONEDIMENSIONAL CALCULATIONS; SUM RULES; TRAPPING; TRAPS
Citation Formats
Fuchs, J.N., Leyronas, X., Combescot, R., and Laboratoire de Physique Statistique, Ecole Normale Superieure, 24 rue Lhomond, 75231 Paris Cedex 05. Hydrodynamic modes of a onedimensional trapped Bose gas. United States: N. p., 2003.
Web. doi:10.1103/PhysRevA.68.043610.
Fuchs, J.N., Leyronas, X., Combescot, R., & Laboratoire de Physique Statistique, Ecole Normale Superieure, 24 rue Lhomond, 75231 Paris Cedex 05. Hydrodynamic modes of a onedimensional trapped Bose gas. United States. doi:10.1103/PhysRevA.68.043610.
Fuchs, J.N., Leyronas, X., Combescot, R., and Laboratoire de Physique Statistique, Ecole Normale Superieure, 24 rue Lhomond, 75231 Paris Cedex 05. 2003.
"Hydrodynamic modes of a onedimensional trapped Bose gas". United States.
doi:10.1103/PhysRevA.68.043610.
@article{osti_20640373,
title = {Hydrodynamic modes of a onedimensional trapped Bose gas},
author = {Fuchs, J.N. and Leyronas, X. and Combescot, R. and Laboratoire de Physique Statistique, Ecole Normale Superieure, 24 rue Lhomond, 75231 Paris Cedex 05},
abstractNote = {We consider two regimes where a trapped Bose gas behaves as a onedimensional (1D) system. In the first one the Bose gas is microscopically described by 3D meanfield theory, but the trap is so elongated that it behaves as a 1D gas with respect to lowfrequency collective modes. In the second regime we assume that the 1D gas is truly 1D and that it is properly described by the LiebLiniger model. In both regimes we find the frequency of the lowest compressional mode by solving the hydrodynamic equations. This is done by making use of a method which allows us to find analytical or quasianalytical solutions of these equations for a large class of models approaching very closely the actual equation of state of the Bose gas. We find an excellent agreement with the recent results of Menotti and Stringari obtained from a sumrule approach.},
doi = {10.1103/PhysRevA.68.043610},
journal = {Physical Review. A},
number = 4,
volume = 68,
place = {United States},
year = 2003,
month =
}

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