Design and optimization of a coaxial Bragg resonator for a 350 GHz cyclotron autoresonance maser (CARM) oscillator

By utilizing the scatter matrix method, a coaxial Bragg resonator for a cyclotron autoresonance maser (CARM) oscillator operating in the TE₆₁ mode at frequency of 350 GHz, is designed, analyzed, and optimized. Peculiarities of both the reflector and resonator, including the frequency spectra, the resonant frequencies, the quality factors are calculated. Single mode and multimode results are compared, which demonstrates that single-mode treatment is not reasonable. An optimization method of improving the performance of the resonator is presented, where the deterioration by the mode coupling between the operating mode and its competing modes is considered. Numerical simulation shows that the optimized coaxial Bragg resonator has an obvious improvement in performance and can be used to construct a THz high-power CARM oscillator.