Robust, long-life cathodes

Photocathodes are critical components for advanced accelerators, light sources, and ultra-fast electron microscopy. Cathodes with high quantum efficiency, however, currently exhibit lifetimes measured in tens to hundreds of hours. This program is developing new configurations that can potentially increase the lifetimes by 2-3 orders of magnitude. The new configurations also provide more robust cathodes capable of recovering from gas exposure that disables current cathodes. This paper describes the improved configuration and presents experimental measurements. It also describes the new program to extend this technology to photocathodes with higher quantum efficiency and establish production capability.