Emergence of topological Hall effect in half-metallic manganite thin films by tuning perpendicular magnetic anisotropy

TL;DR

This paper demonstrates the emergence of the topological Hall effect in half-metallic manganite thin films by tuning perpendicular magnetic anisotropy through strain and doping, leading to skyrmion formation and new functional possibilities.

Contribution

It introduces a method to induce topological Hall effect in manganite films by controlling magnetic anisotropy, enabling skyrmion stabilization in these materials.

Findings

Topological Hall effect observed in strained, doped manganite films.

Skyrmions with high topological charge identified in real-space.

Tuning magnetic anisotropy balances dipolar interactions to stabilize skyrmions.

Abstract

Magnetic materials hosting topological spin textures like magnetic skyrmion exhibit nontrivial Hall effect, namely, topological Hall effect (THE). In this study, we demonstrate the emergence of THE in thin films of half-metallic perovskite manganites. To stabilize magnetic skyrmions, we control the perpendicular magnetic anisotropy by imposing a compressive epitaxial strain as well as by introducing a small Ru doping. When the perpendicular magnetic anisotropy is tuned so that it is balanced with the magnetic dipolar interaction, the film exhibits a sizable THE in a magnetization reversal process. Real-space observations indicate the formation of skyrmions and some of them have high topological charge number. The present result opens up the possibility for novel functionalities that emerge under keen competition between the skyrmion phase and other rich phases of perovskite manganites with various orders in spin, charge, and orbital degrees of freedom.