Enhanced spin pumping efficiency in antiferromagnetic IrMn thin films around the magnetic phase transition

TL;DR

This study demonstrates enhanced spin pumping efficiency in IrMn antiferromagnetic thin films near their magnetic phase transition, revealing critical temperature dependence and interfacial spin mixing conductance enhancements.

Contribution

It provides experimental evidence of increased spin pumping at the phase transition in IrMn films and links it to interfacial spin mixing conductance, advancing understanding of spin transport in antiferromagnets.

Findings

Enhanced damping observed near the IrMn phase transition

Thickness dependence of the critical temperature determined

Characteristic length for spin-spin interactions deduced

Abstract

We report measurement of a spin pumping effect due to fluctuations of the magnetic order of IrMn thin films. A precessing NiFe ferromagnet injected spins into IrMn spin sinks, and enhanced damping was observed around the IrMn magnetic phase transition. Our data was compared to a recently developed theory and converted into interfacial spin mixing conductance enhancements. By spotting the spin pumping peak, the thickness dependence of the IrMn critical temperature could be determined and the characteristic length for the spin-spin interactions was deduced.