Effective pairing interactions in a doped band insulator under circularly polarized light

Floquet formalism has been applied to construct theories for manipulating material properties. We investigate the pairing properties in a doped band insulator under a periodic driving field. We employ a correlated fermion model on a honeycomb lattice, in which correlation effects give rise to pairing interactions, and derive an effective model for doped fermions under circularly polarized light (CPL). We show the tunable effective pairing interactions under CPL and find the optimal region leading to attractive contributions for doped fermions. We discuss the bound state and pairing symmetry by solving the two-body problem in the effective model. Our results suggest that Floquet theory enables us to engineer interactions for superconducting pair formation in strongly correlated systems.