Weyl points enabling significant enhancement of thermoelectric performance in an antiferromagnetic van der Waals metal GdTe3

TL;DR

This paper demonstrates that Weyl points in the topological material GdTe3 significantly enhance thermoelectric performance under magnetic fields, achieving record power factors in metallic systems.

Contribution

It reveals the role of Weyl points and magnetic field-induced topological transition in boosting thermoelectric properties of GdTe3, a topological antiferromagnetic metal.

Findings

GdTe3 exhibits an unsaturated power factor of up to 18846 μW m-1 K-1 at 20 K under 13.5 T.

Thermopower and power factor are enhanced by 873% and 1075% respectively under magnetic field.

Weyl points contribute to thermoelectric enhancement via field-induced topological transition.

Abstract

Magneto-thermoelectric (MTE) effect has demonstrated significant ad-vantages in achieving optimal thermoelectric (TE) properties compared to conventional methods. Topological materials pro-vide a unique platform for investigating the MTE effect, leveraging their exotic electronic structure topology. In this study, we report that the topological material GdTe3 exhibits an unsaturated power factor of up to 18846 {\mu}W m-1 K-1 under a magnetic field of 13.5 T at 20 K, which represents the highest value observed in metallic systems and surpasses most state-of-the-art TE materials. The relative enhancement under magnetic field in thermopower and power factor reaches 873% and 1075%, respectively, attributed to the Weyl points contribution resulting from the field-induced topological transition, as confirmed by our theoretical calculations. Our findings demonstrate a promising candidate for solid-state cooling and reveal the substantial contribution of Weyl points to TE enhancement, thereby offering a novel approach to optimizing TE properties in topological materials.