WG1019
Cornell University, Ithaca, New York, USA
CLASSE, Ithaca, New York, USA
The electron beam brightness in a Linac is limited by the beam brightness at the photocathode. Various photocathode materials are being investigated at Cornell University to optimize the Quantum Efficiency (QE), emittance, response time and lifetime. The photocathode growth procedures and diagnostic techniques being developed at Cornell University are presented. GaAs(Cs,F) and alkali-antimonide are the two kinds of high Quantum Efficiency (QE) photocathodes which are being investigated for use in the Cornell High Energy ERL. GaAs(Cs,F) has the potential to produce sub-thermal emittance electron beams whereas K2CsSb has demonstrated the ability to deliver 20mA of beam current for 8 hours without significant QE decay.
