Large out-of-plane spin-orbit torque in topological Weyl semimetal candidate TaIrTe4

TL;DR

This paper reports a significant out-of-plane spin-orbit torque in the topological Weyl semimetal candidate TaIrTe4, which could enable more energy-efficient spintronic devices without external magnetic fields.

Contribution

The study demonstrates a large out-of-plane damping-like spin-orbit torque in TaIrTe4, a topological Weyl semimetal, with high spin Hall conductivity, advancing spintronic technology.

Findings

Large out-of-plane SOT efficiency observed at room temperature.

Out-of-plane spin Hall conductivity is an order of magnitude higher than in other materials.

Potential for energy-efficient, field-free spintronic devices.

Abstract

Topological quantum materials, with novel spin textures and broken crystal symmetries are suitable candidates for spintronic memory technologies. Their unique electronic properties, such as protected surface states and exotic quasiparticles, can provide an out-of-plane spin polarized current needed for external field free magnetization switching of magnets with perpendicular magnetic anisotropy. Conventional spin-orbit torque materials, such as heavy metals and topological insulators, provide only an in-plane spin polarized current, and recently explored materials with lower crystal symmetries provide very low out-of-plane spin polarized current components, which is not suitable for energy-efficient spin-orbit torque (SOT) applications. Here, we demonstrate a large out-of-plane damping-like SOT at room temperature using a topological Weyl semimetal candidate TaIrTe4 with a lower crystal symmetry. We performed spin-orbit torque ferromagnetic resonance (STFMR) experiments in a TaIrTe4/Ni80Fe20 heterostructure and observed a large out-of-plane damping-like SOT efficiency. The out-of-plane spin Hall conductivity is estimated to be an order of magnitude higher than the reported values in other materials. These findings of high spin Hall conductivity and large out-of-plane SOT efficiency are suitable for the development of energy efficient and external field-free spintronic devices.