Investigation of the gyrotron oscillator as a nonlinear electrodynamical system

This paper deals with the investigation of the gyrotron oscillator as a nonlinear electrodynamical system. Recent physics investigations of this class of radiation mechanisms, both in theory and in experiment are reported. We have also demonstrated the stationary operation of backward wave oscillations at a beam current far in excess of the generally predicted nonstationary threshold. The difference in nonlinear behavior is shown to be fundamental through a comparative analysis of the feedback mechanisms, energy deposition profiles, and field shaping process involved in these two types of oscillations. Formation of axial modes in the gyrotron backward wave oscillator is examined in the perspective of optimum conditions for beam-wave interactions. Nonlinear implications of these properties are investigated with time dependent simulations.