Multi-alkali antimonides have been proposed as a promising class of photocathode materials for particle accelerators. First-principles results have recently complemented the experimental efforts in the characterization of these systems [1]. However, most of the existing studies focus on bulk crystals and still little is known about their surface properties. We fill this gap with an ab initio...
A surface modification technique is described that significantly enhances the photoelectric quan-
tum efficiency (QE) of Nb at 248 nm by more than two orders of magnitude, thereby making this
material suitable potentially as a cathode for superconducting radiofrequency (SRF) photoinjectors. The approach uses ultra-thin-film metallic coatings that exploit proximity coupled superconductivity,...
