Double-Beam Gyrotron With Frequency Multiplication

A new scheme of a two-resonator self-exciting frequency gyromultiplier based on the use of two coaxial hollow electron beams is proposed and theoretically investigated. Efficient cogeneration of two waves excited at different cyclotron harmonics in such a scheme is achieved due to a special choice of the beam radii, when one of the beams provides excitation of the first cavity at the fundamental cyclotron resonance, whereas the other excites the second cavity at a high cyclotron harmonic. For such a gyromultiplier, calculations predict the possibility of terahertz generation at the third cyclotron harmonic with a watt-level power, when the electron beam parameters are acceptable for realization of the continuous-wave operation.