Polyakov loop and the color-flavor locked phase of quantum chromodynamics

We consider the Polyakov-Nambu-Jona-Lasinio model with three massless quarks at high density and moderate temperature in the superconductive color-flavor locking phase. We compute the critical temperature Tc as a function of the baryonic chemical potential for the phase transition from the superconductive state to the normal phase. We find that Tc is higher by a factor 1.5-2 in comparison to the model containing no Polyakov loop. We also compute the specific heat Cv near the second-order phase transition and we show that the inclusion of the Polyakov loop does not change the value of the critical exponent.