Document Type
Conference Paper
Publication Date
2025
Publication Title
20th International Workshop on Polarized Source, Targets, and Polarimetry (PSTP)- PoS
Volume
472
Pages
056
Conference Name
20th International Workshop on Polarized Source, Targets, and Polarimetry, 22-27 September 2024, Jefferson Lab
Abstract
[First slide] Direct band-gap photocathode (Eg = 1.42 eV).
Valence band maximum (VBM) is doubly degenerate, Max. electron spin polarization (ESP) ~35-40%.
Strained-supperlattice (SSL) removed the VBM degeneracy, ESP ~85-90% with QE of ~1% at 780 nm.
Requires UHV: Lifetime ~200 C with ~200 μA beam current.
Ion-back bombardment degrades the lifetime.
Improvement in charge lifetime required for JLAB polarized positron source program: 1mA-10mA beam current for 2 weeks ~ 10³10⁴C.
Rights
© 2026 The Authors under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
Original Publication Citation
Rahman, M. A. A., Blume, G., Mamun, M. A., Zhang, S., & Elsayed-Ali, H. (2025). Quantum efficiency, electron spin polarization and lifetime study for GaAs based truncated nanocone array photocathodes. 20th International Workshop on Polarized Source, Targets, and Polarimetry (PSTP2024) - PoS. 472, 056. https://pos.sissa.it/472/056/
Repository Citation
Rahman, Md. Aziz Ar; Blume, Greg; Mamun, Md Abdullah; Zhang, Shukui; and Elsayed-Ali, Hani, "Quantum Efficiency, Electron Spin Polarization and Lifetime Study for GaAs Based Truncated Nanocone Array Photocathodes" (2025). Electrical & Computer Engineering Faculty Publications. 607.
https://digitalcommons.odu.edu/ece_fac_pubs/607
ORCID
0000-0002-1329-5018 (Elsayed-Ali)