Abstract
We compute the shear viscosity of a superfluid atomic Fermi gas in the unitarity limit. The unitarity limit is characterized by a divergent scattering length between the atoms, and it has been argued that this will result in a very small viscosity. We show that in the low temperature limit the shear viscosity scales as , where the universal parameter relates the chemical potential and the Fermi energy, . Combined with the high temperature expansions of the viscosity our results suggest that the viscosity has a minimum near the critical temperature . A naïve extrapolation indicates that the minimum value of the ratio of viscosity over entropy density is within a factor of of the proposed bound .
- Received 23 July 2007
DOI:https://doi.org/10.1103/PhysRevA.76.053607
©2007 American Physical Society