Spin pumping and inverse spin Hall effect in iridium oxide

TL;DR

This study demonstrates that polycrystalline IrO2 exhibits high spin Hall conductivity and angle, making it a promising material for spintronic devices due to its effective spin pumping and inverse spin Hall effect.

Contribution

First detailed investigation of spin pumping and inverse spin Hall effect in IrO2, showing its comparable performance to platinum in spintronic applications.

Findings

IrO2 exhibits high spin Hall conductivity.

Significant contribution of spin pumping to ISHE signal.

Comparable spin Hall angle to platinum.

Abstract

Large charge-to-spin conversion (spin Hall angle) and spin Hall conductivity are prerequisites for development of next generation power efficient spintronic devices. In this context, heavy metals (e.g. Pt, W etc.), topological insulators, antiferromagnets are usually considered because they exhibit high spin-orbit coupling (SOC). In addition to the above materials, 5d transition metal oxide e.g. Iridium Oxide (IrO 2 ) is a potential candidate which exhibits high SOC strength. Here we report a study of spin pumping and inverse spin Hall effect (ISHE), via ferromagnetic resonance (FMR), in IrO 2 /CoFeB system. We identify the individual contribution of spin pumping and other spin rectification effects in the magnetic layer, by investigating the in-plane angular dependence of ISHE signal. Our analysis shows significant contribution of spin pumping effect to the ISHE signal. We show that polycrystalline IrO 2 thin film exhibits high spin Hall conductivity and spin Hall angle which are comparable to the values of Pt.