Abstract
In this talk, I will present a systematic study of the bulk viscosity of s- and p-wave Fermi gases with a finite effective range near scattering resonance. I will make a comparison between the s- and p-wave Fermi gases near resonance regarding bulk viscosities and the effects of scale invariance breaking by effective range in the high-temperature limit. Two parameters, relating to the scattering length and the effective range, are found to determine the bulk viscosity and scale invariance breaking in each case. Importantly, we find that the imaginary part of the fermion self-energy in which the role the effective range is dominant plays a crucial role in determining the bulk viscosities. However, the effective range plays a very different role in the two cases. For an s-wave Fermi gas at resonance, the bulk viscosity vanishes, and scale invariance is recovered when the effective range is tuned to zero. Unlike the s-wave case, in the p-wave Fermi gas, even in the limit of vanishing effective range, the scale invariance remains broken which leads to a non-zero bulk viscosity.
Anyone interested is welcome to attend.