  We investigate Rashba spin-orbit coupled Fermi gases in square optical
lattice by using the determinant quantum Monte Carlo (DQMC) simulations which
is free of the sign-problem. We show that the Berezinskii-Kosterlitz-Thoules
phase transition temperature is firstly enhanced and then suppressed by
spin-orbit coupling in the strong attraction region. In the intermediate
attraction region, spin-orbit coupling always suppresses the transition
temperature. We also show that the spin susceptibility becomes anisotropic and
retains finite values at zero temperature.
