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Hydrodynamic modes and pulse propagation in a cylindrical Bose gas above the Bose-Einstein transition

T. Nikuni·A. Griffin
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Abstract

We study hydrodynamic oscillations of a cylindrical Bose gas above the Bose-Einstein transition temperature using the hydrodynamic equations derived by Griffin, Wu and Stringari. This extends recent studies of a cylindrical Bose-condensed gas at T=0. Explicit normal mode solutions are obtained for non-propagating solutions. In the classical limit, the sound velocity is shown to be the same as a uniform classical gas. We use a variational formulation of the hydrodynamic equations to discuss the propagating modes in the degenerate Bose-gas limit and show there is little difference from the classical results.

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T. Nikuni, A. Griffin. 1998-06-09. Hydrodynamic modes and pulse propagation in a cylindrical Bose gas above the Bose-Einstein transition. https://doi.org/10.1103/physreva.58.4044

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