arXiv:cond-mat/0701251·v4·cond-mat.other
The Shear Viscosity to Entropy Density Ratio of Trapped Fermions in the Unitarity Limit
Thomas Schaefer (North Carolina State University)🇺🇸
Abstract
We extract the shear viscosity to entropy density ratio \eta/s of cold fermionic atoms in the unitarity limit from experimental data on the damping of collective excitations. We find that near the critical temperature \eta/s is roughly equal to 1/2 in units of \hbar/k_B. With the possible exception of the quark gluon plasma, this value is closer to the conjectured lower bound 1/(4\pi) than any other known liquid.
Comments: published version