Polarized infrared and raman spectroscopy studies of the liquid crystal E7 alignment in composites based on grooved silicon

Alignment of liquid-crystal filler molecules and the electro-optical effect in composite photonic crystals based on grooved silicon are studied. It is found that the nematic liquid crystal molecules that fill the grooves are predominantly aligned in a planar configuration with respect to the silicon walls. The liquid crystal molecules are realigned homeotropically with respect to the groove walls under the influence of an electric field. The effect detected can be used to adjust the photonic band gap of a one-dimensional photonic crystal. (c) 2005 Pleiades Publishing, Inc.