Nonlinear Simulation of a Cyclotron Autoresonance Maser (CARM) Operating in a Transverse Magnetic Mode

Abstract

In the gyrotron operation, the transverse-magnetic (TM) mode is excluded because the TM mode instability vanishes when the vacuum waveguide mode and the beam mode are at grazing incidence. However, situation changes in a cyclotron autoresonance maser (CARM) interaction. In this paper nonlinear formulation of a TM-mode CARM is derived, and detailed simulations are presented for the TM1,1-mode CARM. Simulation results show that a TM1,1-mode CARM can reach high power of megawatts and ultrahigh gain of more than 70 dB, as a TE1,1-mode gyrotron traveling wave tube (gyro-TWT) and TE1,1-mode CARM did in the reported experiments.