English

Hydrodynamic modes in a trapped Bose gas above the Bose-Einstein transition

Condensed Matter 2009-10-28 v1

Abstract

We discuss the collective modes of a trapped Bose gas in the hydrodynamic regime where atomic collisions ensure local thermal equilibrium for the distribution function. Starting from the conservation laws, in the linearized limit we derive a closed equation for the velocity fluctuations in a trapped Bose gas above the Bose-Einstein transition temperature. Explicit solutions for a parabolic trap are given. We find that the surface modes have the same dispersion relation as the one recently obtained by Stringari for the oscillations of the condensate at T=0T=0 within the Thomas-Fermi approximation. Results are also given for the monopole ``breathing'' mode as well as for the m=0m=0 excitations which result from the coupling of the monopole and quadrupole modes in an anisotropic parabolic well.

Keywords

Cite

@article{arxiv.cond-mat/9610187,
  title  = {Hydrodynamic modes in a trapped Bose gas above the Bose-Einstein transition},
  author = {A. Griffin and Wen-Chin Wu and S. Stringari},
  journal= {arXiv preprint arXiv:cond-mat/9610187},
  year   = {2009}
}

Comments

4 pages, no figure, submitted to Phys. Rev. Lett