Robust RF Photocathodes

Photocathodes are one of the most critical components in RF-based linacs and light source systems. Current photocathodes lack the capability to meet the long term requirements for medical, defense, industrial and many scientific systems. This program will develop a new generation of photocathodes that provide high performance and long life. Calabazas Creek Research Inc. (CCR), in collaboration with the University of Maryland, demonstrated that reservoir thermionic cathode technology can be applied to photocathodes to extend life time by two orders of magnitude. This program will apply this technology to develop photocathodes that also provide high quantum efficiency using selected surface coatings. The goal will be quantum efficiencies exceeding 0,5% in the UV and ability to recover from contamination. An additional goal will be lifetimes exceeding 20,000 hours. Commercial Applications and Other Benefits: Photocathodes are a key component in many accelerator and light source systems. Current lifetimes and performance limit applications to research purposes; however, extending the lifetime and robustness will allow development of systems for industrial, defense, scientific, and medical applications.