Characteristics Of Complete Bandgap Of Two Dimensional Annular Photonic Crystal

Photonic crystal is a kind of manufactured micro-structure with periodic arrangement of dielectric constant. Photonic bandgap structure of photonic crystal indicates its primary property, which is the base of its design and application, The study on photonic bandgap structure is an important part of basic research on photonic crystal. In this paper, some researches have been done about the photonic bandgap of two dimensional annular photonic crystal by the plane wave expansion method(PWM). The theoretic results have particularly great importance for developing photonic crystals with big bandgap and optical devices of photonic crystal. As follows are the main contents in the paper:1. The relation between complete bandgap and three main influence factors (lattice structure, fill ratio, dielectric constant ratio of two dimensional air hole photonic crystals based on GaAs, Ge) is studied. According to the computed result, we mainly studied structures of complete bandgap of two dimensional quasi-annular photonic crystals based on Ge in triangular lattice, of which inner-scatter shapes were rectangular, square, hexagonal, respectively. The annular structure with circle inner-scatter, also was studied for comparison. For seeking the structural parameters of biggest complete bandgap and the change regularity of the bandgap, the fill ratio, dielectric constant ratio, rotating angle of inner-scatters and outside radius of air ring are changed.2. The relation between complete bandgap and three main influence factors (lattice structure, fill ratio, dielectric constant ratio of two dimensional dielectric column and dielectric annular photonic crystal based on GaAs, Ge) is studied. According to the computed result, we mainly studied dielectric annular structures which are easily to get complete bandgap. For seeking the structural parameters of biggest complete bandgap and the change regularity of the bandgap, the fill ratio, dielectric constant ratio of inner-scatters and outside radius of dielectric ring are changed.