Self-diffraction of light waves by a local photorefractive grating in a crystal of the symmetry group bar $\bar43m$ in the transverse configuration

The exact solution of nonlinear equations describing the symmetric stationary interaction of two light waves of an arbitrary polarisation on a local photorefractive grating in a crystal of the symmetry group $\bar43m$ in the transverse configuration of crystal faces is obtained in the paraxial limit. The polarisation of light waves and efficiency of energy transfer between them are studied as functions of the reduced length of a sample and the intensity ratio of incident waves.