OPTICAL REORIENTATION IN DYE-DOPED NEMATICS

We present our most recent results on laser-induced optical reorientat ion in mixtures made by adding small amounts of organic dyes to nemati c liquid crystals. The optical reorientation process is biased by the molecular interaction between dye and nematic host, so that the reorie ntation is dramatically enhanced. Measurements of this enhancement hav e been performed on several guest-host mixtures in order to get inform ation on the nematic-dye molecular interaction. Our results seem to in dicate that the presence of strong dipolar group as CN in the nematic host may play a significant role in the observed effect.