Large Spin‐Orbit Torque with Multi‐Directional Spin Components in Ni<sub>4</sub>W
Abstract
AbstractSpin‐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.
Article Details
Authors (18)
Yifei Yang
Key Laboratory of Ocean Observation and Forecasting, Key Laboratory of Marine Geology and Environment, Institute of Oceanology, Chinese Academy of Sciences
Seungjun Lee
Department of Electrical and Computer Engineering, University of Minnesota−Twin Cities
Yu‐Chia Chen
Department of Electrical and Computer Engineering University of Minnesota Minneapolis MN 55455 USA
Qi Jia
Brahmdutta Dixit
Department of Electrical and Computer Engineering University of Minnesota Minneapolis MN 55455 USA
Duarte Sousa
Department of Electrical and Computer Engineering University of Minnesota Minneapolis MN 55455 USA
Michael Odlyzko
Characterization Facility University of Minnesota Minneapolis MN 55455 USA
Javier Garcia‐Barriocanal
Characterization Facility University of Minnesota Minneapolis MN 55455 USA
Guichuan Yu
Greg Haugstad
Characterization Facility University of Minnesota Minneapolis MN 55455 USA
Yihong Fan
Department of Electrical and Computer Engineering, University of Minnesota 1 , Twin Cities, Minneapolis, Minnesota 55455,
Yu‐Han Huang
Department of Electrical and Computer Engineering University of Minnesota Minneapolis MN 55455 USA
Deyuan Lyu
Department of Electrical and Computer Engineering, University of Minnesota 1 , Twin Cities, Minneapolis, Minnesota 55455,
Zach Cresswell
Department of Chemical Engineering and Materials Science University of Minnesota Minneapolis MN 55455 USA
Shuang Liang
State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry
Onri Jay Benally
Department of Electrical and Computer Engineering, University of Minnesota 1 , 200 Union St. SE, Minneapolis, Minnesota 55455,
Tony Low
Department of Electrical and Computer Engineering, University of Minnesota−Twin Cities
Jian‐Ping Wang
Department of Electrical and Computer Engineering University of Minnesota Minneapolis MN 55455 USA