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Updated: Jul 2, 2026
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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
Intense source of spin-polarized electrons.
L A Hodge1, F B Dunning, G K Walters
1Department of Physics, Rice University, Houston, Texas 77001.
The Review of Scientific Instruments
|January 1, 1979
Summary
Researchers developed a novel source of spin-polarized electrons using optically oriented helium atoms. This inexpensive source provides high-quality electron beams suitable for low-energy spin-dependent scattering experiments.
Area of Science:
- Atomic Physics
- Quantum Mechanics
- Electron Scattering
Background:
- Spin angular momentum conservation is crucial in atomic collisions.
- Optically oriented atoms provide a method for generating polarized particles.
- Chemiionization reactions are key processes in plasma and gas discharges.
Purpose of the Study:
- To develop an efficient source of spin-polarized electrons.
- To utilize spin angular momentum conservation in chemiionization reactions.
- To provide a tool for low-energy spin-dependent scattering experiments.
Main Methods:
- Exploiting spin angular momentum conservation in chemiionization reactions.
- Using optically oriented He(2(3)S) atoms in a flowing helium afterglow.
- Extracting transversely or longitudinally polarized electrons.
Main Results:
- Achieved polarized electron beam currents of approximately 2 muA at 40% polarization.
- Demonstrated an effective emittance of approximately 2 mrad/cm for electron energies from 100-400 eV.
- Observed an energy spread of less than 0.15 eV and readily reversible polarization.
Conclusions:
- The developed source is relatively inexpensive and practical.
- The source is suitable for most proposed low-energy spin-dependent scattering experiments.
- This work advances the capabilities for spin-polarized electron generation.
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