The influence of structure parameters on terahertz wave filter based on photonic crystal ring cavity

Terahertz (THz) communication has important applications in high-speed and ultra-broadband wireless access networks. THz filter is one of the key device of WDM communications. THz filter based on ring cavity photonic crystal (TFRCPC) has many advantages such as simple structure, high integration and high flexibility. According to the coupling characteristics of waveguide and ring cavity, a novel structure of TFRCPC was proposed in this paper, the TFRCPC consists of 4×3 internal dielectric cylinder with four scattering dielectric cylinder. The influence of structure parameters of TFRCPC is mainly studied. The simulation results show that, on the basis of basal material of Si and lattice constant of 30µm, when the radius of dielectric cylinder is 5.7368µm, the radius of 4×3 internal dielectric cylinder is 3.5µm, the radius of scattering dielectric cylinder is 5µm, the wave at 83.535µm wavelength can go through the structure with the transmittance of 0.97674.