Research of metal-dielectric photonic crystal accelerating structures

In the design of high intensity rf accelerators, Photonic crystal has been suggested to suppress unwanted high order modes (HOMs) and avoid rf breakdown. Base on the conception, we select a metal-dielectric (Copper + sapphire) PBG based cavities(named with pillbox structures) to establish an overmoded photonic crystal accelerating structure which consists of dielectric rods and metal disks with irises. The band gap calculation for 2D triangular crystal lattice of dielectric rods has been performed with plane wave expansion method (PWM). From the results, we simulated the accelerator structures with Microwave Studio, and optimized the dimensions for the operating higher-order TM02-like mode approaching communication frequency at 9.37GHz.The S-Parameters with the coupled probes was simulated at last.