Joule–Thomson Coefficient for Strongly Interacting Unitary Fermi Gas

Abstract

The Joule–Thomson effect reflects the interaction among constituent particles of macroscopic system. For classical ideal gas, the corresponding Joule–Thomson coefficient is vanishing while it is non-zero for ideal quantum gas due to the quantum degeneracy. In recent years, much attention is paid to the unitary Fermi gas with infinite two-body scattering length. According to universal analysis, the thermodynamical law of unitary Fermi gas is similar to that of non-interacting ideal gas, which can be explored by the virial theorem P = 2E/3V. Based on previous works, we further study the unitary Fermi gas properties. The effective chemical potential is introduced to characterize the nonlinear levels crossing effects in a strongly interacting medium. The changing behavior of the rescaled Joule–Thomson coefficient according to temperature manifests a quite different behavior from that for ideal Fermi gas.