Vectorial two-beam coupling with arbitrary shifted photorefractive gratings: an analytical approach

An analytical solution is presented to the vectorial coupled wave equations for the steady state amplitudes of two waves interacting in cubic photorefractive crystals. The solution accounts for pump depletion as well as an arbitrary phase shift between the interference pattern and photorefractive grating. It is shown that bidirectional vectorial amplification and polarization orthogonalization of the interacting beams take place in photorefractive crystal with diffusion, drift or mixed mechanism of space-charge formation.