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Collective mode damping and viscosity in a 1D unitary Fermi gas

M. Punk·W. Zwerger
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Abstract

We calculate the damping of the Bogoliubov-Anderson mode in a one-dimensional two-component attractive Fermi gas for arbitrary coupling strength within a quantum hydrodynamic approach. Using the Bethe-Ansatz solution of the 1D BCS-BEC crossover problem, we derive analytic results for the viscosity covering the full range from a Luther-Emery liquid of weakly bound pairs to a Lieb-Liniger gas of strongly bound bosonic dimers. At the unitarity point, the system is a Tonks-Girardeau gas with a universal constant $α_ζ=0.38$ in the viscosity $ζ=α_ζ\hbar n$ for T=0. For the trapped case, we calculate the Q-factor of the breathing mode and show that the damping provides a sensitive measure of temperature in 1D Fermi gases.

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M. Punk, W. Zwerger. 2006-11-29. Collective mode damping and viscosity in a 1D unitary Fermi gas. https://doi.org/10.1088/1367-2630%2F8%2F8%2F168

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