Photonic band gap accelerator cavity design at 90 GHz

In previous work we have proposed utilizing photonic band gap (PBG) structures as a new class of high-energy, high-intensity accelerator cavities. We have completed extensive MAFIA numerical calculations of multicell PBG structures, with each cell consisting of a square array of metal cylinders terminated by conducting sheets and surrounded by microwave absorber on the periphery. We find that our PBG structure has good higher order mode suppression, superior pumping properties, and potential fabricational advantages when compared to conventional cavity designs. These advantages scale favorably with increasing frequency, leading us to propose use of a PBG accelerator structure at the W-band (91.392 GHz).