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Title: Coupling of hydrodynamics and quasiparticle motion in collective modes of superfluid trapped Fermi gases

Abstract

At finite temperature, the hydrodynamic collective modes of superfluid trapped Fermi gases are coupled to the motion of the normal component, which in the BCS limit behaves like a collisionless normal Fermi gas. The coupling between the superfluid and the normal components is treated in the framework of a semiclassical transport theory for the quasiparticle-distribution function, combined with a hydrodynamic equation for the collective motion of the superfluid component. We develop a numerical test-particle method for solving these equations in the linear-response regime. As a first application we study the temperature dependence of the collective quadrupole mode of a Fermi gas in a spherical trap. The coupling between the superfluid collective motion and the quasiparticles leads to a rather strong damping of the hydrodynamic mode already at very low temperatures. At higher temperatures the spectrum has a two-peak structure, the second peak corresponding to the quadrupole mode in the normal phase.

Authors:
 [1]
  1. Institut de Physique Nucleaire, CNRS and Universite Paris-Sud, 91406 Orsay Cedex (France)
Publication Date:
OSTI Identifier:
20982567
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevA.75.053607; (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; BCS THEORY; BOSE-EINSTEIN CONDENSATION; COUPLING; DISTRIBUTION FUNCTIONS; FERMI GAS; FERMIONS; HYDRODYNAMICS; QUADRUPOLES; SEMICLASSICAL APPROXIMATION; SPECTRA; SPHERICAL CONFIGURATION; SUPERFLUIDITY; TEMPERATURE DEPENDENCE; TRANSPORT THEORY; TRAPPING; TRAPS

Citation Formats

Urban, Michael. Coupling of hydrodynamics and quasiparticle motion in collective modes of superfluid trapped Fermi gases. United States: N. p., 2007. Web. doi:10.1103/PHYSREVA.75.053607.
Urban, Michael. Coupling of hydrodynamics and quasiparticle motion in collective modes of superfluid trapped Fermi gases. United States. doi:10.1103/PHYSREVA.75.053607.
Urban, Michael. Tue . "Coupling of hydrodynamics and quasiparticle motion in collective modes of superfluid trapped Fermi gases". United States. doi:10.1103/PHYSREVA.75.053607.
@article{osti_20982567,
title = {Coupling of hydrodynamics and quasiparticle motion in collective modes of superfluid trapped Fermi gases},
author = {Urban, Michael},
abstractNote = {At finite temperature, the hydrodynamic collective modes of superfluid trapped Fermi gases are coupled to the motion of the normal component, which in the BCS limit behaves like a collisionless normal Fermi gas. The coupling between the superfluid and the normal components is treated in the framework of a semiclassical transport theory for the quasiparticle-distribution function, combined with a hydrodynamic equation for the collective motion of the superfluid component. We develop a numerical test-particle method for solving these equations in the linear-response regime. As a first application we study the temperature dependence of the collective quadrupole mode of a Fermi gas in a spherical trap. The coupling between the superfluid collective motion and the quasiparticles leads to a rather strong damping of the hydrodynamic mode already at very low temperatures. At higher temperatures the spectrum has a two-peak structure, the second peak corresponding to the quadrupole mode in the normal phase.},
doi = {10.1103/PHYSREVA.75.053607},
journal = {Physical Review. A},
number = 5,
volume = 75,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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