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Updated: Jan 12, 2026
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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
10.4K
Ultrafast inverse chirality-induced spin selectivity observed by THz emission.
Yifan Dong1,2, Aeron McConnell3,4, Matthew P Hautzinger1
1National Renewable Energy Laboratory, Golden, CO, USA.
Science (New York, N.Y.)
|November 6, 2025
Summary
Chirality-induced spin selectivity (CISS) generates ultrafast charge currents from spin currents. This study directly measured these currents using terahertz emission spectroscopy, revealing spin-charge coupling dynamics in chiral materials.
Area of Science:
- Condensed matter physics
- Spintronics
- Chiral materials science
Background:
- Chirality-induced spin selectivity (CISS) links structural chirality, spin orientation, and charge current.
- Conventional methods like magnetoresistance lack temporal resolution for spin-charge interconversion dynamics.
- Inverse CISS converts spin currents into charge currents, a phenomenon requiring direct measurement.
Purpose of the Study:
- To directly measure ultrafast charge currents generated by inverse CISS.
- To investigate the temporal dynamics of spin-charge interconversion in chiral systems.
- To elucidate the fundamental coupling between spin and charge currents in chiral materials.
Main Methods:
- Utilized terahertz (THz) emission spectroscopy for picosecond time-resolved measurements.
- Employed polarity and polarization analysis of THz emission to map induced charge current direction.
- Investigated spin injection into chiral systems to probe inverse CISS.
Main Results:
- Directly detected ultrafast charge currents resulting from inverse CISS with picosecond resolution.
- Observed that the generated charge current flows along the spin orientation.
- Demonstrated that the charge current direction reverses with stereochemical configuration, confirming spin-charge coupling.
Conclusions:
- Ultrafast charge currents are directly generated by inverse CISS in chiral systems.
- Terahertz emission spectroscopy provides a powerful tool to study spin-charge dynamics.
- These findings offer fundamental insights into the coupling between spin and charge in chiral materials.
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