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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
Magnon-Mediated Orbital Torque Switching through an Antiferromagnetic Insulator
Hui Yang1, Zehan Chen1, Weikai Luo1
1College of New Materials and New Energies, Shenzhen Technology University, Shenzhen 518118, China.
Nano Letters
|May 30, 2026
Summary
Researchers demonstrated magnon-mediated orbital torque, an orbital analogue of spin-orbit torque. This novel mechanism efficiently controls magnetization in spintronic devices using reduced currents, paving the way for advanced orbitronics.
Area of Science:
- Spintronics and Magnetism
- Condensed Matter Physics
- Materials Science
Background:
- Spin-orbit torque (SOT) is a key mechanism for controlling magnetization in spintronic devices.
- Magnon-mediated SOT offers a promising route for enhanced efficiency.
- The orbital analogue of SOT, orbital torque, is less explored.
Purpose of the Study:
- To provide experimental evidence for magnon-mediated orbital torque.
- To investigate the role of the orbital Hall effect and antiferromagnetic ordering in this phenomenon.
- To explore the potential for efficient magnetization manipulation in orbitronic devices.
Main Methods:
- Fabrication of Ti/NiO/CoPt heterostructures.
- Electrical transport measurements to probe current-induced torques.
- Analysis of the dependence of torque on the antiferromagnetic state of NiO.
Main Results:
- Experimental demonstration of magnon-mediated orbital torque.
- Identification of the orbital Hall effect in the Ti layer as the driving mechanism.
- Observation of strong dependence on NiO antiferromagnetic ordering, indicating magnon-mediated orbital angular momentum transport.
- Efficient manipulation of perpendicular magnetization with reduced electrical currents.
Conclusions:
- Magnon-mediated orbital torque is a viable mechanism for magnetization control.
- This effect enables efficient orbitronic devices.
- The study highlights the potential of antiferromagnetic insulators in mediating orbital angular momentum transport.
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