Shear viscosity and spin diffusion coefficient of a two-dimensional Fermi gas

Abstract

Using kinetic theory, we calculate the shear viscosity and the spin diffusion coefficient as well as the associated relaxation times for a two-component Fermi gas in two dimensions, as a function of temperature, coupling strength, polarization, and mass ratio of the two components. It is demonstrated that the minimum value of the viscosity decreases with the mass ratio, since Fermi blocking becomes less efficient. We furthermore analyze recent experimental results for the quadrupole mode of a 2D gas in terms of viscous damping obtaining a qualitative agreement using no fitting parameters.