Nernst effect experiments in magnetic thin films
The Nernst effect describes the transverse electric field that arises in an electrical conductor subject to both a thermal gradient and a magnetic field. Hereby, the Nernst electric field, the thermal gradient, and the magnetic field are mutually orthogonal. In magnetically ordered materials, the Nernst response is usually subdivided into an ordinary Nernst contribution scaling with the externally applied magnetic field, and an anomalous Nernst contribution scaling with the magnetic order parameter (the magnetization). In the last few years, an additional so-called topological Nernst effect connected to non-collinear spin structures or topology has been vividly discussed.
In the first part of the talk, I will introduce the different Nernst effect contributions just mentioned, and compare them to their Hall effect counterparts. The second part of the talk will then be devoted to recent experimental developments. In particular, I will discuss our recent experiments resolving the topological Hall and topological Nernst response in thin Mn1.8PtSn films with non-collinear spin structure, and address spatially resolved anomalous Nernst effect experiments in antiferromagnetic Mn3Sn thin films.
(*) Persons who do not have a CEA badge must request an entry authorization sufficiently in advance, before November 18th at sabrina.megias@cea.fr, or celine.conche@cea.fr