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Updated: Jun 25, 2025
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Visualizing Uniaxial-strain Manipulation of Antiferromagnetic Domains in Fe1+YTe Using a Spin-polarized Scanning Tunneling Microscope
Published on: March 24, 2019
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Spin-Orbit Torque in Single-Molecule Junctions from ab Initio
María Camarasa-Gómez1,2, Daniel Hernangómez-Pérez1,3, Ferdinand Evers1
1Institute of Theoretical Physics, University of Regensburg, 93040 Regensburg, Germany.
The Journal of Physical Chemistry Letters
|May 22, 2024
Summary
Researchers calculated spin-orbit torques (SOT) in single-molecule junctions, showing electric fields can control magnetic moments. This work advances understanding of SOT at the molecular level for future spintronic devices.
Area of Science:
- Condensed Matter Physics
- Molecular Spintronics
- Quantum Chemistry
Background:
- Spin-orbit torques (SOT) offer nonmagnetic control of magnetic moments in heterojunctions lacking spatial inversion symmetry.
- Implementing SOT at the single-molecule level presents significant challenges.
Purpose of the Study:
- To perform first-principles calculations of SOT in single-molecule junctions under bias.
- To investigate SOT beyond linear response in molecular systems.
- To understand the microscopic mechanisms of SOT in single molecules.
Main Methods:
- Utilizing a self-consistency scheme combining density functional theory (DFT) and nonequilibrium Green's function (NEGF) theory.
- Including spin-orbit interaction in the calculations.
- Computing magnetization changes with bias voltage and current-induced SOT.
Main Results:
- Quantitative estimates for SOT in single-molecule junctions were obtained within the linear regime.
- Calculated SOT values are comparable to those observed in magnetic interfaces.
- The study provides a detailed microscopic picture of SOT phenomena in molecular junctions.
Conclusions:
- First-principles calculations demonstrate the feasibility of SOT in single-molecule junctions.
- The findings suggest potential for electric-field control of magnetism at the molecular scale.
- This research contributes to the fundamental understanding required for molecular spintronics.
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