Author: Velazquez, D.G.
Paper Title Page
TUPPD070 Kelvin Probe Studies of a Cesium Telluride Photocathode for the AWA Photoinjector 1566
  • E.E. Wisniewski, K.C. Harkay, Z.M. Yusof
    ANL, Argonne, USA
  • L.K. Spentzouris, J. Terry, D.G. Velazquez, E.E. Wisniewski
    Illinois Institute of Technology, Chicago, Illinois, USA
  Cesium telluride is an important photocathode as an electron source for particle accelerators. It has a relatively high quantum efficiency (>1%), is sufficiently robust in a photoinjector, and has a long lifetime. This photocathode is grown in-house for the new Argonne Wakefield Accelerator (AWA) to produce high charge per bunch (~50 nC). Here, we present a study of the "work function" of a cesium telluride photocathode using the Kelvin Probe technique. The study includes an investigation of the correlation between the quantum efficiency and the work function, the effect of photocathode aging, the surprising effect of UV exposure on the work function, and the puzzling behavior of the work function during and after photocathode rejuvenation via heating.