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Shear viscosity and damping for a Fermi gas in the unitarity limit

G. M. Bruun·H. Smith
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Abstract

The shear viscosity of a two-component Fermi gas in the normal phase is calculated as a function of temperature in the unitarity limit, taking into account strong-coupling effects that give rise to a pseudogap in the spectral density for single-particle excitations. The results indicate that recent measurements of the damping of collective modes in trapped atomic clouds can be understood in terms of hydrodynamics, with a decay rate given by the viscosity integrated over an effective volume of the cloud.

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G. M. Bruun, H. Smith. 2007-03-26. Shear viscosity and damping for a Fermi gas in the unitarity limit. https://doi.org/10.1103/physreva.75.043612

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