Electron bunching in stepped electric-field profiles

Abstract

On the basis of analytical considerations and numerical simulation, this work demonstrates that transit-time tubes with stepped RF electric-field profiles can provide electron conversion efficiency in excess of 40 percent. This represents a two-fold enhancement in the conversion efficiency in comparison with that obtained with a longitudinally uniform electric-field distribution. Such an improvement arises from a phase synchronization process due to the action of RF electric fields of reversed signs along the interaction space.