Defect Mode in One-Dimensional Photonic Crystal with In-Plane Switchable Nematic Liquid Crystal Defect Layer

A defect mode in a one-dimensional (1D) photonic crystal (PC) with an in-plane switchable nematic liquid crystal (NLC) as a defect layer has been investigated. Two types of defect modes appear in the photonic band gap of the transmission spectrum. They are associated with the extraordinary and ordinary refractive indices of the NLC in the defect aligning perpendicular to the propagation direction of the light. The defect mode position does not shift upon the in-plane reorientation of the NLC molecules, but the peak intensity changes with rotating the director of the NLC around the light propagating axis. On the basis of these defect modes, the polarization direction of the light passing through the 1D PC with the in-plane switchable NLC can be electrically controlled by changing the field direction in the defect layer.