RF modulation of a 3 mA beam current from a carbon nanotube cathode

A micro-triode operating at 30 GHz is currently under development. This triode is composed of two 30 GHz re-entrant resonant cavities (input and output, respectively cathode-grid space and anode-grid space) separated by a grounded thin metallic grid. A dc bias between cathode-grid and anode-grid provides a continuous electron beam. The superposition of a 30 GHz electric field created in the input cavity, leads to increase the average grid current, which is indicative of the electron beam modulation.