Anisotropic self-diffraction of phase-modulated elliptically polarized beams in gyrotropic photorefractive crystals

A matrix calculation of the spectrum of signal-beam intensity oscillations at anisotropic self-diffraction of phase-modulated beams in gyrotropic photorefractive crystals is performed. It is shown that the spectrum of these oscillations at local and nonlocal photoresponses depends strongly on the polarization of recording beam. This circumstance makes it possible to control the sensitivity of a holographic interferometer for nonlinear-response diagnostics by choosing optimal elliptical polarizations of beams for a particular mode of grating recording.