Long-life photocathodes with high quantum efficiency

This program is 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 sealing a reservoir of cesium chromate and titanium powders. An integral heater provides a controlled 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. A facility is being developed to fabricate the cathodes and transport them to user facilities.