Compact cold-cathode electron buncher

Summary form only given, as follows. We are developing a compact high-frequency electron buncher for applications in the next generation of microwave tubes and electron accelerators. This electron buncher uses a conventional Pierce-type electron gun with a gated field-emitter-array cathode for the production of short, 10 kV, 100 mA electron bunches. The width of the bunches can be adjusted to be a small part of the period of the driving signal. We have tested these cold-cathodes in dc mode and have been able to obtain up to 120 mA of emission current in a stable manner. We have begun to assemble an experiment for high-frequency testing of these devices and will report our preliminary results.