Robust, long-life photocathodes

Calabazas Creek Research, Inc. and the University of Maryland are developing high quantum efficiency (QE) reservoir cathodes for accelerators, free-electron lasers, ultra-fast electron microscopes and other applications. High QE materials are deposited on an emitter allowing diffusion of cesium from a reservoir. An integral heater provides a continuous flow of cesium to replace that lost by evaporation, thereby extending the lifetime of the cathode. Experiments demonstrated these cathodes can recover from poisoning events, including atmospheric contamination for some cathodes. A facility is nearing completion to fabricate the cathodes, including equipment for vacuum transport to user facilities.