Floquet engineering of 2D materials

Abstract

We demonstrate theoretically that the interaction of electrons in the 2D materials (gapped graphene and transition metal dichalchogenide monolayer) with a strong off-resonant electromagnetic field substantially renormalizes their band structure, including the band gaps and the spin-orbit splitting. Moreover, the renormalized electronic parameters drastically depend on the field polarization. Namely, a linearly polarized field always decreases the band gap (and, particularly, can turn the gap into zero), whereas a circularly polarized field breaks the equivalence of valleys in different points of the Brillouin zone and can both increase and decrease corresponding band gaps. As a consequence, the field can serve an effective tool to control spin and valley properties of the 2D materials and be potentially exploited in optoelectronic applications.