Structural Dependence of Group Velocity and Leakage Loss in 1-D Photonic Crystal Coupled Resonator Optical Waveguide With Modulated Mode-Gap

One-dimensional photonic crystal coupled resonator optical waveguide (1-D PC-CROW) based on mode-gap confinement has a possibility to reduce leakage losses compared with conventional 1-D PC-CROW constructed by placing defects periodically. However, transmission characteristics of 1-D PC-CROW based on mode-gap confinement have not been investigated so far. In this paper, we evaluate structural dependence of group velocity and leakage losses of 1-D PC-CROW by using the 3-D vector finite element method for periodic waveguide analysis. We show that such 1-D PC-CROW can realize small group velocity and low leakage losses simultaneously by investigating dispersion relationships of 1-D PC-CROW.