Nonlinear analysis of the quasi-optical electron cyclotron maser

A new classical electron cyclotron maser oscillator is proposed and analyzed. The configuration utilizes an open resonator cavity, in which a gyrating electron beam translates along an external magnetic field, directed transverse to the axis of symmetry of the resonator. The linear and nonlinear interaction between the electrons and resonator fields has been analyzed and an expression for the steady state efficiency obtained. From the numerical solution of the slow-time scale equations, results have been obtained, which show that, e.g., for a uniform external magnetostatic field total efficiencies in excess of 30% can be realized, while appropriately contouring the field increases the efficiency to ∼ 45%.