Two-Fluid Hydrodynamics in Trapped Bose Gases and in Superfluid Helium
نویسندگان
چکیده
A review is given of recent theoretical work on the superfluid dynamics of trapped Bose gases at finite temperatures, where there is a significant fraction of non-condensate atoms. One can now reach large enough densities and collision cross-sections needed to probe the collective modes in the collisiondominated hydrodynamic region where the gas exhibits characteristic superfluid behavior involving the relative motions of the condensate and noncondensate components. The precise analogue of the Landau-Khalatnikov two-fluid hydrodynamic equations was recently derived from trapped Bose gases, starting from a generalized Gross-Pitaevskii equation for the condensate macroscopic wavefunction and a kinetic equation for the non-condensate atoms. PACS numbers: 03.75.Fi, 05.30.Jp, 67.40.Bz, 67.40-w.
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