Large Spin‐Orbit Torque with Multi‐Directional Spin Components in Ni<sub>4</sub>W
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 Ni<sub>4</sub>W at room temperature is reported, as evaluated by second harmonic Hall measurements. In addition, due to the low crystal symmetry of Ni<sub>4</sub>W, 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/Ni<sub>4</sub>W (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 Ni<sub>4</sub>W, highlighting its potential as a low-symmetry SOT material for energy-efficient spintronic devices.
Authors
- Tony Low (ORCID: https://orcid.org/0000-0002-5759-5899)
- Javier García‐Barriocanal
- Shuang Liang (ORCID: https://orcid.org/0000-0003-1491-2839)
- Greg Haugstad (ORCID: https://orcid.org/0000-0003-0459-7476)
- Onri Jay Benally (ORCID: https://orcid.org/0000-0002-8391-9105)
- Brahmdutta Dixit (ORCID: https://orcid.org/0009-0008-4471-3877)
- Deyuan Lyu (ORCID: https://orcid.org/0000-0001-6552-9763)
- Zach Cresswell (ORCID: https://orcid.org/0000-0002-7624-2271)
- Jian‐Ping Wang (ORCID: https://orcid.org/0000-0003-2815-6624)
- Qi Jia (ORCID: https://orcid.org/0009-0008-3209-0422)
- D. J. P. de Sousa
- Yifei Yang
- Seungjun Lee (ORCID: https://orcid.org/0000-0003-3129-5086)
- Yu‐Han Huang (ORCID: https://orcid.org/0000-0002-4276-3060)
- Yu‐Chia Chen (ORCID: https://orcid.org/0000-0001-6669-1308)
- Yihong Fan (ORCID: https://orcid.org/0000-0001-9554-0541)
- Guichuan Yu (ORCID: https://orcid.org/0000-0002-7533-6911)
- Michael Odlyzko
Institutions
- University of Minnesota (US)
Publication Details
- Journal
- Advanced Materials
- Published
- 2025-05-15
- DOI
- https://doi.org/10.1002/adma.202416763
- Citations
- 9
- Primary Topic
- Magnetic properties of thin films
- Type
- article
- Field-Weighted Citation Impact
- 11.22
Funders
- National Science Foundation
- Semiconductor Research Corporation
- University of Minnesota
- National Research Foundation
- Ministry of Education
- National Research Foundation of Korea
- National Institute of Standards and Technology
- Materials Research Science and Engineering Center, Harvard University
- Division of Materials Research
- Division of Electrical, Communications and Cyber Systems