Studying the impact of interface roughness on a layered photonic crystal as a sensor

Abstract

Abstract This study investigates the impact of the interface roughness on a layered photonic crystal as a gas sensor based on Tamm resonance in the terahertz range. The well-known transfer matrix method is used for simulation. The sensor's performance is observed for various thicknesses of the rough layer (exponential-graded refractive index layer) between the adjacent layers. The rise in the rough layer between adjacent porous and cavity layers causes a decrease in sensitivity but enhances the quality factor and figure of merit of the proposed structure. However, the change in the thickness of the rough layer between the metallic and the last cavity layer does not affect the performance.