Quasienergy spectrum of electrons in ac-driven graphene superlattice

Quasienergy spectrum of electrons in graphene superlattice subjected to the high-frequency electric field has been derived in tight-binding and non-resonant approximations. The high-frequency electric field has been shown to redistribute the electron gas within the miniband at certain intervals of amplitudes so strongly that the graphene superlattice becomes a medium with a population inversion. In this case the dissipative soliton propagation has been shown to be possible in ac-driven graphene superlattice.