1996/10/25 by Allan Griffin, A. Griffin, Wen-Chin Wu +1 · 2 citations
Physics and Astronomy · #Bose gas #Bose–Einstein condensate #Bose–Einstein statistics #Cold Atom Physics and Bose-Einstein Condensates #Condensed matter physics #Dispersion relation #Magnetic monopole #Physics #Quadrupole #Quantum electrodynamics #Quantum mechanics #Quantum, superfluid, helium dynamics #Strong Light-Matter Interactions #cond-mat
paper · pdf · doi:10.1103/physrevlett.78.1838
4 pages, no figure, submitted to Phys. Rev. Lett
arxiv created 1996/10/25 · openalex publication_date 1997/03/10 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
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 above the transition have the same dispersion relation as the one recently obtained by Stringari for the oscillations of the condensate at T\phantom\rule0ex0ex=\phantom\rule0ex0ex0 within the Thomas-Fermi approximation. Results are also given for the monopole ``breathing'' mode as well as for the m\phantom\rule0ex0ex=\phantom\rule0ex0ex0 excitations which result from the coupling of the monopole and quadrupole modes in an anisotropic parabolic well.