Generation of high-frequency electron beam space charge self-oscillations

One of the main applications of high current pulsed electron beams is the generation of high-power microwave by a resonant interaction between the eigenmodes of a slow wave structure and the electron beam space charge self-oscillations. The latter can be produced by the formation of a virtual cathode in a drift space, when the current amplitude of the injected beam into this space exceeds its limiting value. I will present two approaches to generate a high frequency modulated electron beam which will be useful for microwave generation which were investigated both numerically and experimentally. Namely it was shown that by persistently over-injection of a vacuum diode one can obtain space-charge oscillations and releases a high frequency electron bunches. The other approach considers a setup in which a squeezed state of a magnetized high current electron beam is realized and supplies a leakage current which interacts with a resonant cavity to produce a high-frequency periodic train of electron bunches.  

!! The lecture will take place via zoom, the link:   https://technion.zoom.us/j/99322361289 !!