Photonic band gaps in highly ionic medium: CuCl, CuBr, CuI

Abstract Using the transfer-matrix-method, we have studied the propagation of electromagnetic waves through two-dimensional (2D) and three-dimensional (3D) dispersive photonic band gap (PBG) structures constructed from copper halides materials, especially from CuCl compounds. A special attention has been paid to the effect of the polariton gap on the PBG properties. This study reveals that “Twin gaps” and “Twin brothers” concepts and the flattened bands phenomena in both polarizations and for both structures (i.e. 2D and 3D) are all consequences of the strong photon–phonon coupling, particularly near the long wave length transverse optical phonon frequency. Furthermore, results for comparis…