Large anomalous Nernst effect in the ferromagnetic Fe3Si polycrystal

TL;DR

This paper reports the experimental discovery of a large anomalous Nernst effect in Fe3Si polycrystals at room temperature, driven by intrinsic Berry curvature, highlighting its potential for thermoelectric applications.

Contribution

First experimental demonstration of large ANE in Fe3Si polycrystals, confirming theoretical predictions and identifying its intrinsic Berry curvature origin.

Findings

Large Nernst coefficient (~2 μV/K) observed at room temperature.

Transverse thermoelectric coefficient (~3 A/m·K) measured, indicating significant ANE.

Fe3Si's high Curie temperature and abundant elements make it promising for thermoelectric devices.

Abstract

The high-throughput calculation predicts that the Fe-based cubic ferromagnet Fe$_3$Si may exhibit a large anomalous Nernst effect (ANE). Here, we report our experimental observation of the large Nernst coefficient $S_{yx}\sim$2 $\mu$V/K and the transverse thermoelectric coefficient $-\alpha_{yx}$ $\sim$ 3 Am$^{-1}$K$^{-1}$ for Fe$_3$Si polycrystal at room temperature. The large $-\alpha_{yx}$ indicates that the large ANE originates from the intrinsic Berry curvature mechanism. The high Curie temperature of 840 K and the most abundant raw elements of Fe and Si make Fe$_3$Si a competitive candidate for Nernst thermoelectric generations.