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arXiv · 1107.4552

Viscosity-entropy ratio of the unitary Fermi gas from zero-temperature elementary excitations

Luca Salasnich·Flavio Toigo
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Abstract

We investigate the low-temperature behavior of the ratio between the shear viscosity ηand the entropy density s in the unitary Fermi gas by using a model based on the zero-temperature spectra of both bosonic collective modes and fermonic single-particle excitations. Our theoretical curve of η/s as a function of the temperature T is in qualitative agreement with the experimental data of trapped ultracold 6Li atomic gases. We find the minimum value η/s \simeq 0.44 (in units of \hbar/k_B) at the temperature T/T_F \simeq 0.27, with T_F the Fermi temperature.

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Luca Salasnich, Flavio Toigo. 2011-07-22. Viscosity-entropy ratio of the unitary Fermi gas from zero-temperature elementary excitations. https://doi.org/10.1007/s10909-011-0391-8

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