Near-infrared longitudinal plasmon polariton photonic gaps in a semiconductor metamaterial photonic crystal

We perform a theoretical investigation on the near-infrared longitudinal plasmon polariton gaps in a one-dimensional semiconductor metamaterial photonic crystal. The considered structure is (AB)^N where N is the number of periods, layer A is a dielectric, and layer B is a semiconductor metamaterial composed of Al-doped ZnO (AZO) and ZnO. For oblique incidence under transverse magnetic mode, it is found that, due to the anisotropic permittivity of semiconductor metamaterial, there exist multiple longitudinal plasmon polariton gaps which are ascribed to the coupling between photon mode and metamaterial bulk electric plasmon. The photonic band and gap structures are investigated as functions of incident angle, filling factor of semiconductor metamaterial, thicknesses of constituent layers, and number of periods as well.