Large anomalous Nernst effect in non-crystalline Gd-Fe ferrimagnetic alloy films for flexible thermoelectric applications

TL;DR

This study demonstrates a large anomalous Nernst effect in non-crystalline Gd-Fe alloy films with low magnetization, suitable for flexible thermoelectric devices, achieving high ANE coefficients and maintaining flexibility.

Contribution

It reports the first observation of a large ANE in low-magnetization Gd-Fe films on flexible substrates, highlighting their potential for flexible thermoelectric applications.

Findings

Gd33Fe67 film exhibits an ANE coefficient of 2.13 μV/K.

The Gd33Fe67 film maintains flexibility while producing a significant ANE voltage.

The study suggests potential for flexible thermoelectric devices using Gd-Fe alloys.

Abstract

The anomalous Nernst effect (ANE), a heat-charge conversion mechanism based on a magnetic metal, has been extensively studied for application in thin thermoelectric devices. The low magnetization and fabrication at room temperature are important for flexible ANE thermoelectric devices on plastic substrates. Therefore, we investigated the ANE in ferrimagnetic GdxFe100-x films with low magnetization in this study by systematically varying the Gd composition x. Although the Gd33Fe67 film with a Gd composition close to magnetic compensation composition exhibited very low magnetization, an ANE coefficient |S_ANE| of 2.13 uV/K was obtained, which is close to the highest value reported thus far. Finally, we demonstrated the ANE in a Gd33Fe67 film deposited on a flexible sheet. A sufficient ANE voltage was obtained while maintaining the flexibility of the sample, indicating the potential application of this material in thermoelectric devices exploiting the ANE of Gd-Fe films.