2025-07-17 ミネソタ大学
This low-symmetry material produces powerful spin-orbit torque (SOT)—a key mechanism for manipulating magnetism in next-generation memory and logic technologies. Photo provided by The Nano Magnetism and Quantum Spintronics Lab
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＜関連情報＞
- https://cse.umn.edu/college/news/researchers-demonstrate-new-material-reduce-power-consumption-electronics
- https://advanced.onlinelibrary.wiley.com/doi/10.1002/adma.202416763
Ni4Wにおける多方向スピン成分を含む大きなスピン軌道トルク Large Spin-Orbit Torque with Multi-Directional Spin Components in Ni4W
Yifei Yang, Seungjun Lee, Yu-Chia Chen, Qi Jia, Brahmdutta Dixit, Duarte Sousa, Michael Odlyzko, Javier Garcia-Barriocanal, Guichuan Yu, Greg Haugstad, Yihong Fan, Yu-Han Huang …
Advanced Materials Published: 15 May 2025
DOI:https://doi.org/10.1002/adma.202416763
Abstract
Spin-orbit torque (SOT) offers an efficient mechanism for manipulating the magnetization of ferromagnetic materials in spintronics-based memory and logic devices. However, conventional SOT materials, such as heavy metals and topological insulators, are limited by high crystal symmetry to generating and injecting only in-plane spins into the ferromagnet. Low-symmetry materials and symmetry-breaking strategies have been employed to generate unconventional spin currents with out-of-plane spin polarization, enabling field-free deterministic switching of perpendicular magnetization. Despite this progress, the SOT efficiency of these materials has typically remained low. Here, a large SOT efficiency of 0.3 in the bulk Ni4W at room temperature is reported, as evaluated by second harmonic Hall measurements. In addition, due to the low crystal symmetry of Ni4W, unconventional SOT from the out-of-plane and Dresselhaus-like spin components are observed. Notably, a large SOT efficiency of 0.73 is observed in W/Ni4W (5 nm), potentially resulting from additional interfacial contributions or extrinsic effects. Furthermore, field-free switching of perpendicular magnetization has been achieved using the multi-directional SOT of Ni4W, highlighting its potential as a low-symmetry SOT material for energy-efficient spintronic devices.
