Effect of Geometry on the Electromagnetic Wave Transport Properties of Photonic Crystals: Comparison of Top-Flat and Top-Curved Refractive Index Profiles

Abstract

In the current paper, we try to engineer the refractive index profile in a one-dimensional photonic crystal as a powerful tool to manage the electromagnetic wave transmission properties. For this purpose, we have compared four sinusoidal, rectangular, triangular, and saw-tooth refractive index profile types. In this way, we have used a transfer matrix method accompanied by the discretization of the spatial domain. This method can readily be applied to any arbitrary continuous refractive index profile. Then, we have tried to address the effects of different geometrical and physical parameters, including the photonic crystal length L, dielectric permittivity εd, number of layers and plasma density np, etc. on the light propagation through the mentioned photonic crystals. In the proposed two-layer plasma/dielectric photonic crystals we could observe acceptable ranges of Omni-directional photonic band gaps that their position width and their number can be regulated. We determine the most and least tunable systems.