Transmission response for in-plane and out of plane propagation for a 2D photonic crystal with a planar cavity

Using the transfer matrix technique the transmission response of a rectangular lattice photonic crystal with and without a planar cavity defect has been studied. The response has been studied both within and out of the periodic plane of the crystal for both the perfect and planar cavity defect crystal. The planar cavity defect in the crystal introduces a defect state into the photonic band gap region of the crystal. The frequency of the defect state was predicted to be dependent on the external incidence angle of the exciting plane wave impinging on the crystal. The angular dependence for in-plane propagation has been verified experimentally and found to be in good agreement with predicted results.