PBG structures of novel two-dimensional annular photonic crystals with triangular lattice

摘要

The photonic band gap(PBG) structures of four types of annular photonic crystals(PCs) with inner-scatter of rectangular,square,hexagonal and circle shapes are respectively calculated by the plane wave expansion method.The optimal samples with the largest gap-midgap ratio for each structure are obtained by scanning the four parameters:filling ratio f,dielectric constant ε1,rotating angle θ of inner-scatters and outside radius R of the air ring.The results show that the band gap can be further maximized by adjusting the structural parameters,and a wide PBG with the gap-midgap ratio of 20.4% is gained in the annular photonic crystal with rectangular inner-scatters.