Charge lifetime improvement of the Continuous Electron Beam Accelerator Facility photogun with a biased anode
GaAs photocathodes in dc high-voltage photoguns are highly susceptible to ion back-bombardment, which reduces the photocathode quantum efficiency and limits the useful operating lifetime for producing polarized electron beams. This paper demonstrates that applying a small positive bias to the photogun anode can significantly suppress ion back-bombardment and increase charge lifetime. This technique was studied extensively using the Continuous Electron Beam Accelerator Facility photogun, where highly polarized electron beams created using a strained-superlattice <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:mi>GaAs</a:mi><a:mo>/</a:mo><a:mi>GaAsP</a:mi></a:mrow></a:math> photocathode were used and charge lifetimes improved by almost a factor of 2. A new simulation code was developed to model ion production and tracking in order to better understand and explain the factors that led to the performance improvement. Results of the experiments and simulations are discussed in detail. Published by the American Physical Society 2024
Authors
- Marcy Stutzman (ORCID: https://orcid.org/0000-0001-7460-4796)
- R. Suleiman (ORCID: https://orcid.org/0000-0001-6767-1579)
- Joseph Grames (ORCID: https://orcid.org/0000-0001-9390-8752)
- C. A. Valerio-Lizarraga (ORCID: https://orcid.org/0000-0002-1316-3576)
- C. Hernandez-Garcia (ORCID: https://orcid.org/0000-0002-7594-874X)
- G. Palacios-Serrano (ORCID: https://orcid.org/0000-0002-5331-6127)
- Geoffrey Krafft (ORCID: https://orcid.org/0000-0002-0328-5828)
- J. Hansknecht
- S.B. van der Geer (ORCID: https://orcid.org/0000-0001-8000-4826)
- Joshua Yoskowitz (ORCID: https://orcid.org/0000-0003-1792-6603)
- Sajini Wijethunga (ORCID: https://orcid.org/0000-0002-8765-9208)
- M. Poelker (ORCID: https://orcid.org/0000-0002-5441-137X)
Institutions
- Los Alamos National Laboratory (US)
- Universidad Autónoma de Sinaloa (MX)
- Thomas Jefferson National Accelerator Facility (US)
- Dominion University College (GH)
- Old Dominion University (US)
Publication Details
- Journal
- Physical Review Accelerators and Beams
- Published
- 2024-12-03
- DOI
- https://doi.org/10.1103/physrevaccelbeams.27.123401
- Citations
- 3
- Primary Topic
- Photocathodes and Microchannel Plates
- Type
- article
- Field-Weighted Citation Impact
- 0.55
Funders
- U.S. Department of Energy
- Consejo Nacional de Ciencia y Tecnología
- Office of Science
- Nuclear Physics