Photorefractive response of a cubic gyrotropic crystal with applied square-wave electric field on the interference grating with large contrast

摘要

In the paraxial limit the photorefractive response of a cubic gyrotropic crystal with applied square-wave electric field is considered for the symmetric incidence on a crystal of two plane light waves with approximately equal intensity. The theoretical description is based on the nonlinear equation for the time-average value of the space-charge field and coupled-wave equations for the amplitudes of the eigenwaves of a crystal. It takes into account the additional light waves diffracted in the second orders. The numerical modeling of the self-consistent interaction in Bi_(12)TiO_(20) crystal is made for the diagonal electro-optic configuration of interaction