Two-Fluid Hydrodynamics in Trapped Bose Gases and in Superfluid Helium

Allan Griffin; Tetsuro Nikuni

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arXiv · cond-mat/0009282

Two-Fluid Hydrodynamics in Trapped Bose Gases and in Superfluid Helium

Allan Griffin·Tetsuro Nikuni

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Abstract

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 collision-dominated hydrodynamic region where the gas exhibits characteristic superfluid behavior involving the relative motions of the condensate and non-condensate 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.

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Allan Griffin, Tetsuro Nikuni. 2000-09-19. Two-Fluid Hydrodynamics in Trapped Bose Gases and in Superfluid Helium. https://arxiv.org/abs/cond-mat/0009282

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