Heat-induced damping modification in YIG/Pt hetero-structures

TL;DR

This paper demonstrates that temperature gradients across YIG/Pt heterostructures can modulate magnetization damping, with effects detectable via microwave and electrical measurements, potentially due to thermally-induced spin torques.

Contribution

It introduces a novel method to control magnetization damping using temperature gradients, revealing a thermally-induced spin torque mechanism.

Findings

Damping can be increased or decreased by temperature gradients.

Heat-induced damping variation is detectable via microwave and electrical signals.

The effect suggests a thermally-induced spin torque mechanism.

Abstract

We experimentally demonstrate the manipulation of magnetization relaxation utilizing a temperature difference across the thickness of an yttrium iron garnet/platinum (YIG/Pt) hetero-structure: the damping is either increased or decreased depending on the sign of the temperature gradient. This effect might be explained by a thermally-induced spin torque on the magnetization precession. The heat-induced variation of the damping is detected by microwave techniques as well as by a DC voltage caused by spin pumping into the adjacent Pt layer and the subsequent conversion into a charge current by the inverse spin Hall effect.