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Updated: Aug 14, 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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Chiral-Induced Spin Selectivity and Non-equilibrium Spin Accumulation in Molecules and Interfaces: A First-Principles
Sumit Naskar1,2, Vladimiro Mujica3,4, Carmen Herrmann1,2
1Department of Chemistry, University of Hamburg, Harbor Building 610, Luruper Chaussee 149, 22761Hamburg, Germany.
The Journal of Physical Chemistry Letters
|January 13, 2023
Summary
Electrons moving through chiral molecules exhibit chiral-induced spin selectivity (CISS). This study reveals non-equilibrium spin polarization in carbon helices, offering insights into the CISS mechanism.
Area of Science:
- Condensed Matter Physics
- Quantum Chemistry
- Molecular Electronics
Background:
- Chiral molecules influence electron spin orientation, a phenomenon termed chiral-induced spin selectivity (CISS).
- The precise physical mechanism behind CISS remains incompletely understood.
- Understanding CISS is crucial for developing novel spintronic devices.
Purpose of the Study:
- To investigate the spin polarization of electrons transmitted through chiral molecules.
- To elucidate the underlying physical mechanisms of chiral-induced spin selectivity.
- To explore the role of non-equilibrium electronic structure in CISS.
Main Methods:
- Application of the non-equilibrium Green's function (NEGF) method.
- Integration with the Landauer approach and density functional theory (DFT).
- Computational modeling of carbon helices contacted by gold electrodes.
Main Results:
- Calculations show spin polarization in transmitted electrons through carbon helices.
- Non-equilibrium electronic structure exhibits spin polarization.
- The sign of spin polarization reverses with current direction and molecular handedness.
Conclusions:
- Non-equilibrium spin polarization is a significant factor in understanding CISS.
- Further investigations using hybrid functionals may reveal larger spin polarization effects.
- This study provides a computational framework for exploring CISS in molecular systems.
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