Strong anomalous Nernst effect in collinear magnetic Weyl semimetals without net magnetic moments

TL;DR

This paper predicts a significant anomalous Nernst effect in collinear magnetic Weyl semimetals with zero net magnetic moments, driven by Weyl points and topologically protected, expanding understanding of thermoelectric effects in such materials.

Contribution

It demonstrates for the first time a large anomalous Nernst effect in collinear systems with zero net magnetic moments, linked to Weyl points and topological protection.

Findings

Large anomalous Nernst conductivity predicted in Ti2MnX compounds

Weyl points cause the effect, independent of net magnetic moments

Effect is topologically protected and comparable to noncollinear antiferromagnets

Abstract

We predict a large anomalous Nernst effect in the inverse Heusler compensated ferrimagnets Ti$_2$Mn$X$ ($X$=Al,Ga,In) with vanishing net magnetic moments. Though the net magnetic moment is zero, the Weyl points in these systems lead to a large anomalous Nernst conductivity (ANC) due to the lack of a magnetic sublattice that inverses the sign of the Berry curvature. In comparison to the noncollinear antiferromagnets Mn$_3$Sn and Mn$_3$Ge, the high ANC stems almost entirely from the Weyl points in this class of compounds, and thus, it is topologically protected. This work shows for the first time a large ANC with zero net magnetic moments in collinear systems, which is helpful for comprehensive understanding of the thermoelectric effect in zero-moment magnetic materials and its further applications.