Coherence of a spin-polarized electron beam emitted from a semiconductor photocathode in a transmission electron microscope
- Graduate School of Engineering, Nagoya University, Nagoya 464-8603 (Japan)
- High Energy Accelerator Research Organization (KEK), Tsukuba, Ibaraki 305-0801 (Japan)
- Aichi Synchrotron Radiation Center, Seto 489-0965 (Japan)
The brightness and interference fringes of a spin-polarized electron beam extracted from a semiconductor photocathode excited by laser irradiation are directly measured via its use in a transmission electron microscope. The brightness was 3.8 × 10{sup 7 }A cm{sup −2 }sr{sup −1} for a 30-keV beam energy with the polarization of 82%, which corresponds to 3.1 × 10{sup 8 }A cm{sup −2 }sr{sup −1} for a 200-keV beam energy. The resulting electron beam exhibited a long coherence length at the specimen position due to the high parallelism of (1.7 ± 0.3) × 10{sup −5 }rad, which generated interference fringes representative of a first-order correlation using an electron biprism. The beam also had a high degeneracy of electron wavepacket of 4 × 10{sup −6}. Due to the high polarization, the high degeneracy and the long coherence length, the spin-polarized electron beam can enhance the antibunching effect.
- OSTI ID:
- 22391965
- Journal Information:
- Applied Physics Letters, Vol. 105, Issue 19; Other Information: (c) 2014 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
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