Anomalous Nernst Effect in an Antiperovskite Antiferromagnet

Abstract

The anomalous Nernst effect (ANE), the generation of a transverse electric voltage by a longitudinal temperature gradient, has attracted increasing interest from researchers recently, due to its potential in thermoelectric power conversion and close relevance to the Berry curvature of the band structure. Avoiding the stray field of ferromagnets, the ANE in antiferromagnets (AFMs) has the advantage of realizing highly efficient and densely integrated thermopiles. Here, we report the observation of the ANE in an antiperovskite noncollinear AFM, ${\mathrm{Mn}}_{3}\mathrm{Sn}\mathrm{N},$ experimentally, which is triggered by the enhanced Berry curvature from Weyl points located close to the Fermi level. Considering that antiperovskite ${\mathrm{Mn}}_{3}\mathrm{Sn}\mathrm{N}$ has a rich magnetic phase transition, we modulate the noncollinear AFM configurations by the biaxial strain, which enables us to control its ANE. Our findings provide a potential class of materials to explore the Weyl physics of noncollinear AFMs as well as realizing antiferromagnetic spin caloritronics that exhibits promising prospects for energy conversion and information processing.