▎ 摘　　要

Dispersion properties of surface plasmon polaritons in a semiconductor film with graphene plates in the far-IR range and the possibility of controlling propagation modes due to the change in the chemical potential on one or both plates have been investigated. Dispersion relations for the TE- and TM-polarized waves have been obtained and analyzed, and distributions of the wave field and energy fluxes over the structure have been constructed. Spectral ranges where the surface-wave group velocity is negative are found.