  We investigate the three-dimensional BCS-BEC crossover in the presence of a
Rabi coupling which strongly affects several properties of the system, such as
the chemical potential, the pairing gap and the superfluid density. We
determine the critical interaction strength, below which the system is normal
also at zero temperature. Finally, we calculate the effect of the Rabi coupling
on the critical temperature of the superfluid-to-normal phase transition by
using different theoretical schemes.
