  We numerically study the transport properties of a two-dimensional Fermi gas
in a weakly and strongly interacting regimes, in the range of temperatures
close to the transition to a superfluid phase. For that we excite sound waves
in a fermionic mixture by using the phase imprinting technique, follow their
evolution, and finally determine both their speed and attenuation. Our
formalism incorporates thermal fluctuations via the ground canonical ensemble
description and with the help of Metropolis algoritm. From numerical
simulations we extract temperature dependence of the sound velocity and
diffusivity as well as the dependence on the interaction strength. We emphasize
the role of virtual vortex-antivortex pairs creation in the process of sound
dissipation.

Quantum Gases