Anti-reflection coating for the pass-band of photonic bandgap crystal

摘要

Light transmission is maximized through the pass band of a photonic bandgap (PBG) crystal (having alternating high- and low-index material) while preserving high reflection for stop band. An anti-reflective coating (ARC) is used to coat the PBG crystal wherein the ARC material has a refractive index of n=(n_air×n_{high index material})^1/2 and thickness around λc/8 where λc is center wavelength.