High-repetition-rate ferroelectric-cathode gyrotron

The intensive research on ferroelectric electron-emission mechanisms in the last decade has resulted in a wide understanding of the physics and characteristics of this plasma-assisted electron source. Nevertheless, practical devices employing this cathode were hardly introduced. In this experimental study, a high-repetition-rate microwave oscillator based on a ferroelectric electron gun has been developed. The device operates as a cyclotron-resonance maser in the gyrotron mode. Microwave pulses exceeding 1.5 kW at ∼7 GHz are measured in repetition rates above 3 MHz and duty cycles of ∼50%. These experimental results encourage the implementation of ferroelectric cathodes in practical high-power microwave tubes.