Spatial solitons in photorefractive semiconductors with the Franz-Keldysh effect

The features of the nondiffractive propagation of light beams in photorefractive semiconductors under conditions for manifestation of the Franz-Keldysh effect are investigated. It is shown that the combined influence of electrorefraction and electroabsorption in such materials leads to the formation of inhomogeneous spatial solitons, for which the directions of energy propagation and the phase velocity are different. The dependence of the soliton shape on the parameters of the photorefractive semiconductor and the external electric field strength is established. (C) 1998 American Institute of Physics. [S1063-7842(98)01410-X].