Photon Assisted Electric Field Domains in Semiconductor Doped Superlattices

We study photon-assisted tunneling (PAT) through weakly-coupled doped semiconductor superlattices (SL's) in the high voltage regime. A self-consistent model which treats the Coulomb interaction in a mean field approximation is considered. We discuss the formation of electric field domains in the presence of THz radiation and the appearance of new multistability regions caused by the combined effect of the strong non linearity coming from the Coulomb interaction and the new PAT channels.We show how the electric field domains can be supported by the virtual photonic sidebands due to multiple photon emission and absorption.