Operation of Cs–Sb–O activated GaAs in a high voltage DC electron gun at high average current
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.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Sep 01, 2022
- Source ID
- 10.1063/5.0100794
Entities
People
- Adam Bartnik
- Alice Galdi
- Ivan Bazarov
- Jai Kwan Bae
- Jared Maxson
- Luca Cultrera
- Matthew Andorf
Organizations
- Brookhaven National Laboratory
- Cornell University
- National Science Foundation
- United States Department of Energy
- University of Salerno