Beaming of two-dimensional photonic crystal waveguide based on point defect

Photonic crystal devices in high density integrated optical communication have been widely used. In order to solve space control of the photonic crystal waveguide emitting light beaming, using the method of finite-difference time-domain, the defect waveguide propagation characteristics of photonic crystal waveguide structure are analyzed. Based on optimization of waveguide structure with point defects, through both sides with point defects in the waveguide, the emitting light direction is significantly improved, and the beaming of three-point light interference system is realized. The simulation results show that when the defect state is close to the central band structure, the coupling efficiency of the resonant cavity is higher, when the defect state is close to edge position of the band structure, the coupling efficiency of the resonant cavity is lower, therefore, the selection of point defect in the band 1/4 region can effectively realize the waveguide beaming.