Study Of Defect Effect To Light Transmission Through Waveguide In Photonic Crystal

Photonic crystals are novel optical materials with the photonic band gap. Since photonic crystals can be integrated with semiconductor materials and technology perfectly, photonic crystals will have great application perspective in communication industry and optoelectronic integrated industry in the future. There is an extremely possibility for photonic crystals to be the essential material of photon industry in the future.If the former photonic crystal discrete translational symmetry or geometric shape and physical property of crystal unit disturbed, the band gap will be changed undoubtedly. With different space structures, generally, isolated defect and one dimensional continuous defect are defined as point defect and line defect respectively, and two dimensional continuous defects will be called plane defect. Because of introducing of defects, some localized states can be generated in the former photonic crystal band gap and then, there is a possible for photonic crystal waveguide becomes a true.In this thesis, the Finite Difference Finite Domain Method was adapted to make research about photonic crystal waveguide. Firstly, the transmission property of micro-cavity state in one dimensional photonic crystal waveguide has been discussed. By modulating the crystal cylinder's shape and dielectric contrast, the transmission with TE resonance mode can be enhanced regularly and effectively.Also, a novel shift defect effect has been introduced and applied it into two dimensional photonic crystal cavity waveguide in this thesis. It realized localized state with TM mode transmission in acute bend coupled cavity waveguide in two dimensional photonic crystal and made bending light in whole plane become a possible. Proper sheared shift can make sure higher cavity coupling efficiency and light transmission in the bending waveguide. At the same time, different defect shifts can bend light to different directions.