Development of High-Power Millimeter-Wave Surface-Wave Generators Based on Relativistic Ribbon Electron Beams

We analyze theoretically millimeter-wave surface-wave generators based on relativistic ribbon electron beams within the framework of the averaged quasioptical model, as well as using direct numerical modeling by the Particle-in-Cell method. The regime of excitation of π modes and the regime of the backward-wave oscillator based on a surface wave are studied. The possibility to achieve generation of pulsed radiation at a frequency of 75 GHz with a power of up to 100 MW on the basis of the SINUKI acceleration (IAP RAS) is demonstrated. Experiments have been performed to test experimentally the formation of a relativistic ribbon electron beam with a particle energy of 600 keV, a current of up to 1 kA, and a width of up to 2 cm, which will be used to feed the developed generator.