Phase-space deformation of a dipolar Fermi gas in free expansion

Abstract. We theoretically investigate a polarized dipolar Fermi gas in free expansion. The dipolar-dipolar inter-particle interaction deforms phase-space distribution in trap and also in the expansion. We exactly predict the minimal quadrupole deformation in the expansion for the hightemperature Maxwell-Boltzmann (MB) and zero-temperature Thomas-Fermi (TF) gases in the Hartree-Fock and Landau-Vlasov approaches by developing a new deformation ansatz. In conclusion, we reveal a scaling law associated with the Liouville’s theorem in the long-time behaviors of the MB and TF gases and also provide a proper theoretical approach to develop the time-of-flight method for the dipolar Fermi gas.