Building better electron sources with graphene

Researchers from the U.S. Department of Energy’s Los Alamos National Laboratory, Japan’s High Energy Accelerator Research Organization (KEK), Japan’s National Institutes of Natural Sciences, Nagoya University, and Hiroshima University have discovered that photocathodes that produce electron beams for electron microscopes and advanced accelerators can be refreshed and rebuilt repeatedly if the electron-emitting materials are deposited on layers of graphene. The researchers proposed that the resilience of photocathodes deposited on graphene surfaces was due to weaker binding between the emitter atoms and the underlying carbon layer.