Electrical tuning of refraction in a two-dimensional photonic crystal infilled with a liquid crystal

Abstract

We study a novel electro-optic structure with potential applications for ray steering, optical multiplexers, logic gates or switches. Our idea is based on the electrical tuning of refraction in a two-dimensional photonic crystal infilled by a liquid-crystal, with a direct-current electric field applied parallel to the cylinders. Using a two-step homogenization process, we show that, for sufficiently low frequencies, this structure can be represented by two field-dependent effective refractive indices. We demonstrate that the direction of the ordinary and extraordinary refracted rays can be sensitively tuned by varying the magnitude of the applied field.