Room-temperature perpendicular magnetization switching through giant spin-orbit torque from sputtered BixSe(1-x) topological insulator material

TL;DR

This study demonstrates room-temperature perpendicular magnetization switching using giant spin-orbit torque from sputtered BixSe(1-x) topological insulator films, achieving record spin Hall angle and low switching current density for potential spintronic applications.

Contribution

The paper reports the first observation of giant spin Hall angle and efficient magnetization switching at room temperature using sputtered BixSe(1-x) topological insulator films.

Findings

Spin Hall angle as high as 18.83 at room temperature.

Perpendicular CoFeB switching with a current density of 2.3×10^5 A/cm^2.

Successful growth and switching of perpendicular multilayer on BixSe(1-x) films.

Abstract

The spin-orbit torque (SOT) arising from materials with large spin-orbit coupling promises a path for ultra-low power and fast magnetic-based storage and computational devices. We investigated the SOT from magnetron-sputtered BixSe(1-x) thin films in BixSe(1-x)/CoFeB heterostructures by using a dc planar Hall method. Remarkably, the spin Hall angle (SHA) was found to be as large as 18.83, which is the largest ever reported at room temperature (RT). Moreover, switching of a perpendicular CoFeB multilayer using SOT from the BixSe(1-x) has been observed with the lowest-ever switching current density reported in a bilayer system: 2.3 * 105 A/cm2 at RT. The giant SHA, smooth surface, ease of growth of the films on silicon substrate, successful growth and switching of a perpendicular CoFeB multilayer on BixSe(1-x) film opens a path for use of BixSe(1-x) topological insulator (TI) material as a spin-current generator in SOT-based memory and logic devices.