Botelho S S, Sá de Melo C A R
School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
Phys Rev Lett. 2006 Feb 3;96(4):040404. doi: 10.1103/PhysRevLett.96.040404.
We discuss ultracold Fermi gases in two dimensions, which could be realized in a strongly confining one-dimensional optical lattice. We obtain the temperature versus effective interaction phase diagram for an s-wave superfluid and show that, below a certain critical temperature Tc, spontaneous vortex-antivortex pairs appear for all coupling strengths. In addition, we show that the evolution from weak-to-strong coupling is smooth, and that the system forms a square vortex-antivortex lattice at a lower critical temperature TM.