T-shaped channel-drop filters using photonic crystal ring resonators

In this paper, we demonstrate a new type of 2D photonic crystal T-shaped channel-drop filters based on ring resonators with high normalized transmission; we investigate parameters which affects resonant frequency in these channel-drop filters. These parameters include dielectric constant of inner rods, coupling rods and whole rods of the structure as well as radius of the coupling rods and scatterer rods. At dropping case, the power transferred to the drop waveguide and the power remaining in the bus waveguide are found by finite difference time domain (FDTD) method to be over 95% and less than 5%, respectively.