Vector four-wave mixing of light at reflective gratings in bismuth titanate crystals

摘要

This paper discusses frequency-degenerate vector four-wave mixing of light at reflective photorefractive gratings in cubic gyrotropic crystals. Coupled-wave equations are obtained that describe counterpropagating interaction in crystals of arbitrary cut. Phase conjugation of a weak signal wave at a reflective grating in a (100)-cut bismuth titanate crystal is analyzed for plane-polarized waves. It is established that the reflectance of the conjugate wave depends on the orientation of the polarization vectors of the signal wave and the pump wave and can reach values that substantially exceed 100 under optimal conditions when the thickness of the Bi12TiO20:Fe,Cu crystal is greater than 3 mm. (c) 2006 Optical Society of America.