Liquid crystal molecular orientation in photonic liquid crystal fibers with photopolymer layers

Abstract

Photonic liquid crystal fibers (PLCFs) combine unique properties of photonic crystal fibers and liquid crystals (LCs). Liquid crystal molecules orientation within the PLCFs has crucial impact on their optical properties since it determines the radial refractive index profile of the LC-filled micro-holes. There are many techniques used for LC molecules orientation control, but most of them are not suitable for application in microstructured fibers characterized by holes with diameters in the order of few micrometers. It seems that the only method that could be applied in PLCFs is using of thin photopolymer layers, in which surface anisotropy can be induced in the way of photochemical reactions. In this paper we present preliminary experimental results of the photoinduced molecular alignment in the PLCF induced by a thin polyvinylcinnamate (PVCi) film irradiated with the linearly polarized ultraviolet light.