Generation of a Periodic Train of Ultrashort Microwave Pulses Based on Passive Mode Locking in a Scheme With Two Parallel Electron Beams

In laser physics, a method for generation of ultrashort pulses (USPs) based on passive mode-locking1 is fairly universal and is used for a large number of active media. In papers2,3, a similar method was suggested in application to generation of microwave pulses in a scheme comprising an amplifier and a successive nonlinear bleaching absorber energized by two independent electron beams. However, the practical realization of such a system requires a fairly complicated design which includes the signal transmission between the sections and outcoupling of radiation into the load. In this paper, we present an analysis of an alternate scheme of USP generators with passive mode-locking which feature using of two parallel electron beams formed by a single cathode and transported in common vacuumized interaction space. Both beams interact with the field of the same resonator possessing a quasi-equidistant spectrum of longitudinal modes. One of the electron beams amplifies the radiation while the second one provides nonlinear cyclotron absorption.