Crucial influence of the twist deformation on degenerate four-wave mixing process in homeotropically aligned nematic liquid crystals

Abstract

The diffraction efficiency suppression and peak shifting from the Freedericksz threshold voltage are predicted for degenerate four-wave mixing process in a low-frequency ac voltage-biased homeotropically aligned nematic liquid crystal film. The crucial factor is the twist deformation in the induced phase grating. Significant amounts of diffraction efficiency suppression and peak shift are shown both in numerical and experimental results.