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arXiv · 1705.07248

The Spin-Orbit Torque from a Magnetic Heterostructure with High-Entropy Alloy

Abstract

High-entropy alloy (HEA) is a family of metallic materials with nearly equal partitions of five or more metals, which might possess mechanical and transport properties that are different from conventional binary or tertiary alloys. In this work, we demonstrate current-induced spin-orbit torque (SOT) magnetization switching in a Ta-Nb-Hf-Zr-Ti HEA-based magnetic heterostructure with perpendicular magnetic anisotropy (PMA). The maximum damping-like SOT efficiency from this particular HEA-based magnetic heterostructure is further determined to be $|ζ^{\operatorname{HEA}}_{DL}|\approx0.033$ by hysteresis loop shift measurements, while that for the Ta control sample is $|ζ^{\operatorname{Ta}}_{DL}|\approx0.04$. Our results indicate that HEA-based magnetic heterostructures can serve as a new group of potential candidates for SOT device applications.

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Tian-Yue Chen, Tsao-Chi Chuang, Ssu-Yen Huang, Hung-Wei Yen, Chi-Feng Pai. 2017-05-20. The Spin-Orbit Torque from a Magnetic Heterostructure with High-Entropy Alloy. https://doi.org/10.1103/physrevapplied.8.044005

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