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Updated: May 9, 2026
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Electric-field Control of Electronic States in WS2 Nanodevices by Electrolyte Gating
Published on: April 12, 2018
Energy-efficient field-free switching by orbital torque and spin-reorientation
Bilal Jamshed1, Subhakanta Das1, Pinkesh Kumar Mishra1
1School of Physical and Mathematical Sciences, Nanyang Technological University, 21, Nanyang Link, Singapore.
Nature Communications
|May 7, 2026
Summary
Researchers achieved field-free magnetization switching using orbital torque in synthetic antiferromagnets. This method enhances energy efficiency for spintronic devices by utilizing orbital angular momentum.
Area of Science:
- Spintronics
- Condensed Matter Physics
- Materials Science
Background:
- Spin-orbit torque is crucial for low-power magnetization switching in spintronics.
- Current methods often neglect orbital angular momentum and require external fields, limiting scalability.
- Deterministic switching typically needs in-plane fields, increasing power consumption.
Purpose of the Study:
- To demonstrate energy-efficient, field-free magnetization switching.
- To leverage spin reorientation and orbital torque in synthetic antiferromagnetic structures.
- To explore orbital angular momentum transport for enhanced torque generation.
Main Methods:
- Fabrication of synthetic antiferromagnetic heterostructures.
- Tuning exchange coupling field and magnetic anisotropy.
- Utilizing orbital torque alongside spin torque for magnetization switching.
Main Results:
- Achieved 96% magnetization switching utilizing both spin and orbital torque.
- Demonstrated field-free switching enabled by spin reorientation.
- Increased orbital Hall layer thickness enhanced damping-like torque efficiency by 85% compared to Pt.
Conclusions:
- Orbital angular momentum transport is an efficient torque mechanism in synthetic antiferromagnets.
- This approach offers a scalable route to low-power spintronic devices.
- Field-free switching is achievable by exploiting spin reorientation and orbital torque.
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