Numerical analysis of sharply bent waveguide with microcavity constructed by air-bridge type two-dimensional photonic crystal slab

An efficient sharply bent waveguide with a microcavity constructed by an air-bridge type two-dimensional photonic crystal slab has analyzed. The method of solution is the three-dimensional finite difference time domain (FD-TD) method. An input and an output waveguides are connected by a microcavity. The radius and position of six air-holes surrounding the microcavity are modified to lower the resonant frequency into the photonic band gap. We have confirmed that the optical power is transmitted efficiently into the output waveguide due to resonant tunneling caused by the microcavity.