Year: 2025
Type: article
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.
Source: Advanced Materials
Institutions: University of Minnesota, University of Minnesota System
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $6,070
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
OpenAlex ID: W4410412581