Giant localised spin-Peltier effect due to ultrafast domainwalls motion in antiferromagnetic metals

Abstract

Spin thermo-electric phenomena have attracted wide attention recently, e.g. the Spin Peltier effect (SPE) heat generation by magnonic spin currents. Here we find that the Spin Peltier ef-fect also manifests as a heat wave accompanying fast moving magnetic textures. High speed andextreme magnetic excitation localisation are paramount for efficient transfer of energy from thespin-degrees of freedom to electrons and lattice. While satisfying both conditions is subject to se-vere restrictions in ferromagnets, we find that domain walls in antiferomagnets can overcome theselimitations due to their potential ultrahigh mobility and ultra-small widths originating from the rel-ativistic contraction. To illustrate our findings, we show that electric current driven domain wallmotion in the antiferromagnetic metal Mn2Au can carry a localised heat wave with the maximumamplitude up to 1 K . Since domain walls are well localised nanoscale magnetic objects, this effecthas the potential for nanoscale heating sensing and functionalities.