Longitudinal Spin Seebeck Effect in Silver Strip on CoFe Film

TL;DR

This study experimentally observes the longitudinal spin Seebeck effect in Ag/CoFe bilayers, quantifies the contributions of SSE and ANE to thermal voltages, and calculates the spin current injected at the interface.

Contribution

First experimental demonstration of longitudinal SSE in Ag/CoFe bilayers with detailed separation of SSE and ANE contributions.

Findings

SSE and ANE contributions have a ratio of 4:1.

The spin current injected through CoFe/Ag interface is 1.76 mA/W.

Thermal voltages were effectively separated using comparative measurements.

Abstract

We report the experimental observation of the spin Seebeck effect (SSE) in Ag/CoFe noble metal/magnetic metal bilayers with a longitudinal structure. Thermal voltages jointly generated by the anomalous Nernst effect (ANE) and the SSE were detected across the Ag/CoFe/Cu strip with a perpendicular thermal gradient. To effectively separate the SSE and the ANE part of the thermal voltages, we compared the experimental results between the Ag/CoFe/Cu strip and Cu/CoFe/Cu strip, where two samples processed with the heating power instead of the temperature difference through the thin CoFe film. The respective contributions of the ANE and SSE to thermal voltage were determined, and they have the ratio of 4:1. The spin current injected through CoFe/Ag interface is calculated to be 1.76 mA/W.