Superluminal source of directional pulsed wideband electromagnetic radiation

A photoemission source of directional pulsed wideband electromagnetic radiation in the microwave region is developed, and the time profile of the generated pulse is investigated. The source is a vacuum photodiode of a parabolic shape in which a Cherenkov radiation pulse is formed by an electron current wave excited by an incident laser pulse and propagating along the surface of the anode mesh with a phase velocity higher than the speed of light. © 2014, Allerton Press, Inc.