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Updated: May 20, 2025
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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
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Spin-Polarized Photoelectrons in the Vicinity of Spectral Features
Stefanos Carlström1,2, Rezvan Tahouri1, Asimina Papoulia1
1Lund University, Department of Physics, Box 118, SE-221 00 Lund, Sweden.
Physical Review Letters
|March 25, 2025
Summary
Spin polarization of electrons is efficiently generated via Fano resonances in photoionization, reaching 100% in coincidence measurements. This method offers a general framework for spin-polarized electron generation.
Area of Science:
- Atomic Physics
- Quantum Optics
- Electron Spin Dynamics
Background:
- Photoionization of cesium atoms near Cooper minima produces spin-polarized electrons.
- Fano resonances and Cooper minima involve significant variations in photoionization cross sections with photon energy.
Purpose of the Study:
- To investigate spin polarization generation in rare gas photoionization using Fano resonances.
- To establish a general framework for achieving spin-polarized electrons in photoionization processes.
Main Methods:
- Analysis of angle-resolved photoelectron spectra.
- Coincidence measurements between photoelectrons and photoions.
- Theoretical framework development for photoionization spin polarization.
Main Results:
- Rare gases yield higher overall spin polarization (≥40%) near Fano resonances compared to Cooper minima.
- Spin polarization increases in angle-resolved spectra and reaches 100% in coincidence measurements.
- Large photoionization cross-section variations with photon energy are crucial for efficient spin polarization.
Conclusions:
- Fano resonances in rare gas photoionization are a highly effective method for generating significant electron spin polarization.
- The study provides a universal approach for spin-polarized electron production in various photoionization regimes.
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