Superlattice Photocathode with High Brightness and Long NEA-Surface Lifetime
- Beam Application Team, RIKEN, Wako, Saitama, 351-0198 (Japan)
- Venture Business Laboratory, Nagoya University, Nagoya, 464-8601 (Japan)
- Department of Crystalline Materials Science, Nagoya University, Nagoya, 464-8601 (Japan)
We have suggested that a small momentum spread of photoelectrons and high quantum efficiency can be obtained concurrently by a photocathode using a semiconductor with a superlattice instead of a bulk. We have begun to search for the suitable semiconductor material of a superlattice photocathode for maintaining the surface with a negative electron affinity state for a long time. We measured quantum efficiency degradation of photocathodes using GaAs and AlGaAs semiconductors with various electron affinities. The AlGaAs semiconductor had a quantum efficiency lifetime of 10 times long compared with the GaAs semiconductor. We found that the AlGaAs semiconductor was the suitable material for the superlattice photocathode with the surface maintaining a negative electron affinity state for a long time.
- OSTI ID:
- 21316854
- Journal Information:
- AIP Conference Proceedings, Vol. 1149, Issue 1; Conference: 18. international spin physics symposium, Charlottesville, VA (United States), 6-11 Oct 2008; Other Information: DOI: 10.1063/1.3215590; (c) 2009 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
- Country of Publication:
- United States
- Language:
- English
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