Thermal Emittance and Lifetime of Alkali-Antimonide Photocathodes Grown On GaAs and Molybdenum Substrates Evaluated in a -300 kV dc Photogun

Authors

Y. Wang, Old Dominion UniversityFollow
M. A. Mamun
P. Adderley
B. Bullard
J. Grames
J. Hansknecht
C. Hernandez-Garcia
G. A. Krafft, Old Dominion UniversityFollow
G. Palacios-Serrano, Old Dominion UniversityFollow
M. Poelker
M. L. Stutzman
R. Suleiman
M. Tiefenback
S. Wijethunga, Old Dominion UniversityFollow
J. Yoskowitz, Old Dominion UniversityFollow
S. Zhang

Document Type

Article

Publication Date

2020

DOI

10.1103/PhysRevAccelBeams.23.103401

Publication Title

Physical Review Accelerators and Beams

Volume

23

Issue

10

Pages

11 pp.

Abstract

Cs_xK_ySb photocathodes grown on GaAs and molybdenum substrates were evaluated using a –300 kV dc high voltage photogun and diagnostic beam line. Photocathodes grown on GaAs substrates, with varying antimony layer thickness (estimated range from < 20 nm to > 1 um), yielded similar thermal emittance per rms laser spot size values (~0.4 mm mrad / mm) but very different operating lifetime. Similar thermal emittance was obtained for a photocathode grown on a molybdenum substrate but with markedly improved lifetime. For this photocathode, no decay in quantum efficiency was measured at 4.5 mA average current and with peak current 0.55 A at the photocathode.

Comments

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

Original Publication Citation

Wang, Y., Mamun, M. A., Adderley, P... Wijethunga, S., Yoskowitz, J., Zhang, S., et al. (2020). Thermal emittance and lifetime of alkali-antimonide photocathodes grown on GaAs and molybdenum substrates evaluated in a -300 kV dc photogun. Physical Review Accelerators and Beams, 23(10), 11 pp., Article 103401. https://doi.org/10.1103/PhysRevAccelBeams.23.103401

Repository Citation

Wang, Y.; Mamun, M. A.; Adderley, P.; Bullard, B.; Grames, J.; Hansknecht, J.; Hernandez-Garcia, C.; Krafft, G. A.; Palacios-Serrano, G.; Poelker, M.; Stutzman, M. L.; Suleiman, R.; Tiefenback, M.; Wijethunga, S.; Yoskowitz, J.; and Zhang, S., "Thermal Emittance and Lifetime of Alkali-Antimonide Photocathodes Grown On GaAs and Molybdenum Substrates Evaluated in a -300 kV dc Photogun" (2020). Physics Faculty Publications. 445.
https://digitalcommons.odu.edu/physics_fac_pubs/445