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Reversing Néel Vector in Parity-Time Antiferromagnets by Nonreciprocal Light Scattering
1Center for Alloy Innovation and Design, State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, 710049, China.
Nano Letters
|May 19, 2025
Summary
Researchers propose a new way to control antiferromagnetic (AFM) materials using light. This optical method manipulates the Néel vector in AFM spintronics, paving the way for faster and smaller magnetic storage devices.
Area of Science:
- Spintronics
- Materials Science
- Quantum Optics
Background:
- Antiferromagnetic (AFM) spintronics offers advantages like ultrafast kinetics and zero stray fields.
- Optical control of the AFM Néel vector is a key challenge for advanced magnetic storage.
Purpose of the Study:
- To propose and theoretically validate a nonreciprocal light-scattering mechanism for controlling the AFM Néel vector.
- To explore the use of parity-time (PT) combined AFM multilayers for optical switching.
Main Methods:
- Utilized a low-energy k·p model to describe the system.
- Performed ab initio calculations on MnBi2Te4 and CrI3 thin films.
- Analyzed energy contrasts between bistable Néel polarization states.
Main Results:
- Demonstrated that light handedness and photon frequency can control Néel vector states.
- Parameter-independent calculations align with experimental findings on AFM phase diagrams.
- Confirmed the feasibility of optical switching in PT-combined AFM multilayers.
Conclusions:
- The proposed nonreciprocal light-scattering mechanism offers an effective route for ultrafast photomagnetic control of AFM order.
- This research advances the development of next-generation spintronic devices.
- Optical control of AFM states opens new possibilities in data storage and processing.
Keywords:
Néel vectorantiferromagnetic materialsdensity functional theoryk·p modellight−matter interactionnonreciprocal scatteringMore Related Videos
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