1202.5353 (D. Inotani et al.)

Pseudogap phenomenon in an ultracold Fermi gas with a p-wave pairing
interaction    [PDF]

D. Inotani, R. Watanabe, M. Sigrist, Y. Ohashi

We investigate single-particle properties of a one-component Fermi gas with a
tunable p-wave interaction. Including pairing fluctuations associated with this
anisotropic interaction within a $T$-matrix theory, we calculate the
single-particle density of states, as well as the spectral weight, above the
superfluid transition temperature $T_{\rm c}$. Starting from the weak-coupling
regime, we show that the so-called pseudogap first develops in these quantities
with increasing the interaction strength. However, when the interaction becomes
strong to some extent, the pseudogap becomes obscure to eventually disappear in
the strong-coupling regime. This non-monotonic interaction dependence is quite
different from the case of an s-wave interaction, where the pseudogap simply
develops with increasing the interaction strength. The difference between the
two cases is shown to originate from the momentum dependence of the p-wave
interaction, which vanishes in the low momentum limit. We also identify the
pseudogap regime in the phase diagram with respect to the temperature and the
p-wave interaction strength. Since the pseudogap is a precursor phenomenon of
the superfluid phase transition, our results would be useful for the research
toward the realization of p-wave superfluid Fermi gases.

View original: http://arxiv.org/abs/1202.5353