One-Dimensional Photonic Crystals Based on Anodic Titanium Oxide with a High Q Factor

— Anodic titanium oxide is a promising material for the formation of photonic crystal structures due to its high refractive index, stability in acidic media, and semiconductor conductivity. One-dimensional photonic crystals are obtained by the anodization of titanium with triangle wave modulation of the voltage versus the charge density. The dependence of the position of the photonic band gap on the charge density per anodizing cycle is studied. The reflection coefficient within the photonic band gap of the obtained samples reaches 70%. Taking into account chemical dissolution of the pore walls during anodic oxidation and gradual reduction of the structure period along the film thickness make it possible to obtain photonic crystals based on titanium oxide with a record value of the Q factor of 9.6.