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Updated: Apr 5, 2026
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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 Polarization from Circularly Polarized Light Induced Charge Transfer
Sindhana Pannir-Sivajothi1, David T Limmer1,2,3,4
1Department of Chemistry, University of California, Berkeley, California 94720, United States.
The Journal of Physical Chemistry Letters
|April 4, 2026
Summary
Chiral light exciting achiral molecules can generate spin polarization via electron transfer. This chirality-induced spin selectivity arises from electronic properties and light polarization.
Area of Science:
- Photochemistry
- Quantum Chemistry
- Spin Physics
Background:
- Chirality-induced spin selectivity (CISS) is a phenomenon linking molecular chirality and electron spin.
- Understanding CISS mechanisms is crucial for developing novel spintronic devices.
Purpose of the Study:
- To demonstrate spin polarization generation in achiral systems using chiral light.
- To elucidate the energetic and symmetry requirements for CISS in photoinduced electron transfer.
Main Methods:
- Quantum mechanical rate theories
- Numerical simulations
- Modeling of a metalloporphyrin complex with an axial acceptor ligand
Main Results:
- Spin polarization generated via photoinduced electron transfer in an achiral donor-acceptor complex.
- Chirality emerges from electronic degrees of freedom upon excitation with circularly polarized light.
- Spin polarization is linked to selective excitation of ring currents and depends on spin-orbit coupling.
Conclusions:
- The study proposes a mechanism for generating spin polarization in achiral molecules using chiral light.
- The effect is transient and influenced by spin-orbit coupling and Jahn-Teller distortions.
- Experimental observation is feasible using spin-resolved photoemission spectroscopy.
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