Operation of Cs–Sb–O activated GaAs in a high voltage DC electron gun at high average current
Source abstract
Abstract
Negative Electron Affinity (NEA) activated GaAs photocathodes are the most popular option for generating a high current (>1 mA) spin-polarized electron beam. Despite its popularity, a short operational lifetime is the main drawback of this material. Recent works have shown that the lifetime can be improved by using a robust Cs–Sb–O NEA layer with minimal adverse effects. In this work, we operate GaAs photocathodes with this new activation method in a high voltage environment to extract a high current. We demonstrate that improved chemical resistance of Cs–Sb–O activated GaAs photocathodes allowed them to survive a day-long transport process from a separate vacuum system using a vacuum suitcase. During beam running, we observed spectral dependence on lifetime improvement. In particular, we saw a 45% increase in the lifetime at 780 nm on average for Cs–Sb–O activated GaAs compared to Cs–O activated GaAs.
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Research context
OpenAlex topics: Photocathodes and Microchannel Plates · Radiation Therapy and Dosimetry · Radiation Detection and Scintillator Technologies
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Cornell Laboratory for Accelerator-Based Sciences and Education, Cornell University 1 , Ithaca, New York 14850, USA
Department of Industrial Engineering, University of Salerno 2 , Fisciano (SA) 84084, Italy
Brookhaven National Laboratory 3 , Upton, New York 11973, USA
Funding
U.S. Department of Energy · National Science Foundation
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