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

TL;DR

This study demonstrates current-induced spin-orbit torque switching in a high-entropy alloy-based magnetic heterostructure, revealing its potential for spintronic device applications despite slightly lower efficiency than pure Ta.

Contribution

First demonstration of SOT magnetization switching in a HEA-based heterostructure with perpendicular magnetic anisotropy.

Findings

Maximum damping-like SOT efficiency of HEA is about 0.033.

HEA-based heterostructures can be potential candidates for SOT devices.

Efficiency is comparable to traditional materials like Ta.

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 $|\zeta^{\operatorname{HEA}}_{DL}|\approx0.033$ by hysteresis loop shift measurements, while that for the Ta control sample is $|\zeta^{\operatorname{Ta}}_{DL}|\approx0.04$. Our results indicate that HEA-based magnetic heterostructures can serve as a new group of potential candidates for SOT device applications.