Four-wave mixing by phase-amplitude holographic gratings in the photorefractive piezocrystal of $\bar{4}3m$ symmetry class

A system of coupled-wave equations for calculating the vector amplitudes of linearly polarized light waves at four-wave mixing by phase-amplitude holographic gratings in a cubic photorefractive semiconductor of an arbitrary cut belonging to the $\bar{4}3m$ symmetry class is presented. The dependencies of the intensities of the polarization components of the reversed light wave on the orientation angle for GaAs crystal of (110)-cut are calculated on the basis of the numerical solution of the system of coupled wave equations. The obtained dependences are compared with the known theoretical and experimental data. It is shown that the best agreement between the results of theoretical modeling and experimental data at calculating the contra-directional four-wave mixing in GaAs crystal of (110)-cut is achieved if formation of several phase-amplitude holographic gratings is allowed, and the contribution of the photoelastic and inverse piezoelectric effects are taken into account together with absorption of the crystal.