Development, operation and analysis of bialkali antimonide photocathodes for high-brightness photo-injectors

Different methods for the preparation of KCsSb photocathodes, suitable for electron sources in RF guns, are described in detail. The resulting material has been characterized by Auger depth profiling technique, and by its spectral response in the 250–600 nm range, as well. The results of lifetime experiments under operational and “laboratory” conditions are presented. The role of CO2 in reducing the operational lifetime of the photocathodes and that of O2 in improving the long-wavelength response are investigated.