ErMn₆Sn₆: A Promising Kagome Antiferromagnetic Candidate for Room‐Temperature Nernst Effect‐Based Thermoelectrics

Abstract The Nernst effect, the generation of a tranverse electric voltage in the presence of longitudinal thermal gradient, has garnered significant attention in the realm of magnetic topological materials due to its superior potential for thermoelectric applications. In this work, the electronic and thermoelectric transport properties of a Kagome magnet ErMn₆Sn₆ are investigated, a compound showing an incommensurate antiferromagnetic phase followed by a ferrimagnetic phase transition upon cooling. It is shown that in the antiferromagnetic phase ErMn₆Sn₆ exhibits both topological Nernst effect and anomalous Nernst effect, analogous to the electric Hall effects, with the Nernst coefficient reaching 1.71 µV K⁻¹ at 300 K and 3 T. This value surpasses that of most of previously reported state‐of‐the‐art canted antiferromagnetic materials and is comparable to recently reported other members of RMn₆Sn₆ (R = rare‐earth, Y, Lu, Sc) compounds, which makes ErMn₆Sn₆ a promising candidate for advancing the development of Nernst effect‐based thermoelectric devices.