Evidence of a topological Hall effect in Eu$_{1-x}$Sm$_x$TiO$_3$

TL;DR

This paper reports the observation of a possible topological Hall effect in Eu$_{1-x}$Sm$_x$TiO$_3$ thin films, indicating the presence of nontrivial spin textures like skyrmions in this material system.

Contribution

It provides experimental evidence of a topological Hall effect in Eu$_{1-x}$Sm$_x$TiO$_3$ thin films, a novel finding in this class of materials.

Findings

Hall resistivity shows anomalous Hall effect below 5 K

Additional features at 2 K suggest topological spin textures

Results imply potential for hybrid heterostructures with topological magnetic states

Abstract

We report on the observation of a possible topological Hall effect in thin films of the itinerant ferromagnet Eu1-xSmxTiO3. EuTiO3 and Eu0.955Sm0.045TiO3 films were grown by molecular beam epitaxy. The EuTiO3 film is insulating. The Hall resistivity of the Eu0.955Sm0.045TiO3 films exhibits the anomalous Hall effect below the Curie temperature of ~ 5 K as well as additional features that appear at 2 K. It is shown that these features are magnetic in origin and consistent with the topological Hall effect seen in materials systems with topologically nontrivial spin textures, such as skyrmions. The results open up interesting possibilities for epitaxial hybrid heterostructures that combine topological magnetic states, tunable carrier densities, and other phenomena.