Degenerate Four Wave Mixing in Photorefractive Mesoganic Composites by Counterpropagating-pump geometry

Abstract

Strong optical phase conjugation from high-performance photorefractive mesogenic composites was observed by means of an experimental setup for degenerate four wave mixing. By using counterpropagating-pump geometry, we extensively investigate modulation depth of grating and reflectivity of the phase conjugation mirror, and their dependence on applied electric field and grating constant. Large modulation depth of 3.8×10^<-3> and resulting reflectivity of over 20% was successfully observed in the Bragg grating regime.