Authors

Abstract

Fe5-xGeTe2 is a centrosymmetric, layered van der Waals (vdW) ferromagnet that displays Curie temperatures Tc (270-330 K) that are within the temperature range for spintronic applications. However, little is known about the interplay between topological spin textures (e.g., merons, skyrmions) with technologically relevant transport properties such as the topological Hall effect (THE), or topological thermal transport. Here, we show via high-resolution Lorentz transmission electron microscopy that merons and anti-meron pairs coexist with Nel skyrmions in Fe5-xGeTe2 over a broad range of temperatures and probe their relationship through thermal and electrical transport. We detect a THE even at room T that senses merons at higher Ts as well as their coexistence with skyrmions as T is lowered. Therefore, in Fe5-xGeTe2 the formation and stabilization of distinct thermally driven topological spin textures can be chosen on demand by just adjusting T. Remarkably, we also observe an unconventional THE in absence of Lorentz force and attribute it to the interaction between charge carriers and magnetic field-induced chiral spin textures.