Resonant vectorial wave coupling in cubic photorefractive crystals

We present a theory of resonant photorefractive wave coupling in cubic photorefractive crystals that are in general optically active. This theory includes the resonance enhancement of the photorefractive response in a constant applied electric field, the influence of photoelasticity, and the spatial inhomogeneity of the light intensity. In a unified manner, it allows one to describe the polarization and energy properties of two-wave coupling for the optical configurations relevant to experiment. Applications of the theory are given to photorefractive crystals of the sillenite family.