Tunable resonant narrow-band filter based on electro-optic materials

Abstract

We propose a tunable resonant narrow-band optical filter based on a two-dimensional grating on the top of a stack of dielectric layers including a layer of electro-optic (E-O) material, and demonstrate numerical results of the tunability. The structure is periodic in two orthogonal directions and the basic pattern is designed in order to increase the angular tolerance of the filter. The LiNbO 3 and BaTiO 3 were chosen due to their strong electro-optical properties. When an external electric field is applied on the E-O material layer, a displacement of the resonant peak in the spectra is observed. We have chosen the orientation of each E-O crystal so that the external electric field is applied in the direction corresponding to the greatest E-O coefficient.