Electro-optic Effect and Propagation Loss in Polymer Films Containing Nano-sized Droplets of Liquid Crystal

Abstract

Droplets of liquid crystal (LC) have been energetically investigated during the last ten years.(1) Most of the research has aimed at making use of scattering(2) and diffraction,(3) which occurs either at the surface of individual droplets or at the surface of a layer consisting of many droplets. The droplets were mostly micro-sized. Our aim, however, is to make use of nano-sized LC droplets for active optical devices such as optical switches or tunable filters. The surfaces of nano-sized LC droplets are too small to scatter light, so the total intensity of transmitted light is not changed, but the phase or polarization can be controlled by the birefringence generated by the response of nano-sized LC droplets to an electric field shown in Figure 1. There have been only a few works(4) including ours,5) which have similar aims. We have already reported the preparation of droplets about 50 nm in diameter and shown they respond to an electric field. In this work, we prepared the polymers containing nano-sized LC droplets by various conditions and measured their electro-optic effect, propagation loss, and response time.