In-situ monitoring the magnetotransport signature of topological transitions in the chiral magnet Mn$_{1.4}$PtSn

Andy Thomas; Darius Pohl; Alexander Tahn; Heike Schlörb; Sebastian Schneider; Dominik Kriegner; Sebastian Beckert; Praveen Vir; Moritz Winter; Claudia Felser; Bernd Rellinghaus

arXiv · 2409.16649

In-situ monitoring the magnetotransport signature of topological transitions in the chiral magnet Mn$_{1.4}$PtSn

Andy Thomas·Darius Pohl·Alexander Tahn·Heike Schlörb·Sebastian Schneider·Dominik Kriegner·Sebastian Beckert·Praveen Vir·Moritz Winter·Claudia Felser·Bernd Rellinghaus

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Abstract

Emerging magnetic fields related to the presence of topologically protected spin textures such as skyrmions are expected to give rise to additional, topology-related contributions to the Hall effect. In order to doubtlessly identify this so-called topological Hall effect, it is crucial to disentangle such contributions from the anomalous Hall effect. This necessitates a direct correlation of the transversal Hall voltage with the underlying magnetic textures. We utilize a novel measurement platform that allows to acquire high-resolution Lorentz transmission electron microscopy images of magnetic textures as a function of an external magnetic field and to concurrently measure the (anomalous) Hall voltage in-situ in the microscope on one and the same specimen. We use this approach to investigate the transport signatures of the chiral soliton lattice and antiskyrmions in Mn$_{1.4}$PtSn. Notably, the observed textures allow to fully understand the measured Hall voltage without the need of any additional contributions due to a topological Hall effect, and the field-controlled formation and annihilation of anstiskyrmions are found to have no effect on the measurend Hall voltage.

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Andy Thomas, Darius Pohl, Alexander Tahn, Heike Schlörb, Sebastian Schneider, Dominik Kriegner, Sebastian Beckert, Praveen Vir, Moritz Winter, Claudia Felser, Bernd Rellinghaus. 2024-09-25. In-situ monitoring the magnetotransport signature of topological transitions in the chiral magnet Mn$_{1.4}$PtSn. https://arxiv.org/abs/2409.16649

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