Superfluid state in the periodic Anderson model with attractive interactions

We investigate the periodic Anderson model with attractive interactions by means of dynamical mean-field theory (DMFT). Using a continuous-time quantum Monte Carlo impurity solver, we study the competition between the superfluid state and the paramagnetic Kondo insulating state, and determine the phase diagram. At the chemical potential-induced phase transition from the Kondo insulating state to the superfluid state, a low-energy peak characteristic of the superfluid state appears inside the hybridization gap. We also address the effect of the confining potential in optical lattice systems by means of real-space DMFT calculations.