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Updated: Jul 4, 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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Acoustic spin rotation in heavy-metal-ferromagnet bilayers
Yang Cao1, Hao Ding1, Yalu Zuo1
1Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou, 730000, China.
Nature Communications
|February 2, 2024
Summary
Acoustic spin rotation (ASR) uses lattice vibrations to rotate injected spins, creating a unique inverse spin Hall voltage. This discovery reveals novel spin-orbit coupling and enables acoustic manipulation of spin currents.
Area of Science:
- Spintronics
- Condensed Matter Physics
- Materials Science
Background:
- Spin current injection from ferromagnets into heavy metals is crucial for spintronic devices.
- Understanding spin-orbit interactions is key to controlling spin dynamics.
Purpose of the Study:
- To investigate the phenomenon of acoustic spin rotation (ASR) in ferromagnet/heavy metal heterostructures.
- To quantify the efficiency of ASR and its underlying mechanisms.
- To explore the potential of ASR for spin manipulation in acoustic devices.
Main Methods:
- Utilizing magnetization precession to pump spin current from ferromagnet into heavy metal.
- Analyzing the resulting inverse spin Hall voltage in the heavy metal layer.
- Employing a drift-diffusion model to quantify ASR efficiency.
Main Results:
- Observed an inverse spin Hall voltage with a distinct 90° angular dependency, attributed to ASR.
- Demonstrated that ASR voltage sign remains consistent despite changes in stacking order or heavy metal properties.
- Quantified ASR efficiency up to 30%.
Conclusions:
- ASR, driven by lattice vibrations, effectively rotates injected spins.
- Interface spin-orbit interaction dictates the direction of ASR.
- ASR offers a new pathway for acoustic control of spin currents and reveals a novel spin-orbit coupling.
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