Fermi liquid behavior and Luttinger's theorem close to a diverging scattering length
S. Gaudio, Jason Jackiewicz, Kevin S. Bedell
We derive the thermodynamic properties of a Fermi gas, deep into the quantum degenerate regime. We show that, if Luttinger's theorem holds, a first-order phase transition occurs in the normal phase as a function of the interaction strength. We also show that a volume change occurs at finite temperatures as we go through a divergence in the s-wave scattering length, in the normal phase. The first-order transition has a critical temperature, T *, above the BCS transition temperature. Also, we show that a paramagnetic system in equilibrium, close to the divergence of the scattering length, on the negative side, screens out any applied magnetic field.
arXiv:cond-mat/0703722•The Philosophical Magazine A Journal of Theoretical Experimental and Applied Physics•Jun 20, 2009•2 citations