Design and Simulation of the Beam-wave Interaction System of 400 GHz Clinotron

Abstract

In this paper, the beam-wave interaction system of a continuous wave clinotron oscillator is designed which aims to meet the system application needs of high power source at 400 GHz frequency band. The double corrugated waveguide slow wave structure (SWS) and sheet beam are presented by simulation. The SWS parameters, the parallel electron beam current and inclination angle, and the permanent guiding magnetic field are chosen in the system through optimization using electromagnetic codes and PIC codes. Because of the inclination of the electron beam, the electrons are closer to the SWS and can have stronger interaction with the electric field in order to obtain higher output power. Besides, thicker electron beam can be used when the electron beam is inclined, which also leads to a higher output power. Moreover, there are no absorbers at the SWS ends so that strong reflections will exist at beam inlet and outlet. The simulation results show that the maximum output power is 229.8 mW at frequency of 397 GHz is achieved with beam voltage 10 kV, beam current 120 mA and guiding magnetic field of 1.0 T.