Rotating Larkin-Ovchinnikov-Fulde-Ferrell state of the two-dimensional ultracold Fermi superfluid gas: Reentrant behavior of the critical angular velocity

A rotating ultracold S-wave superfluid Fermi gas is studied when the mismatch in chemical potentials {delta}{mu} (and the population imbalance {delta}n) corresponds to the Larkin-Ovchinnikov-Fulde-Ferrell state in the vicinity of the Lifshitz critical point. It is shown that under these conditions the critical angular velocity {omega}{sub c2} in two-dimensional systems is an oscillating function of temperature and {delta}n giving rise to reentrant superfluid phases. The reason for this behavior is the population by Cooper pairs of the Landau levels (n{>=}1) above the lowest one (n=0)