Giant Domain-Wall Hall Magnetoresistance in Magnetic Topological Semimetal

TL;DR

This paper reports a giant domain-wall Hall magnetoresistance in magnetic topological semimetal Co3Sn2S2, driven by Berry phase effects and significantly larger than in conventional materials, with potential for multi-resistance applications.

Contribution

It introduces a new Hall magnetoresistance mechanism in magnetic Weyl semimetals, linking domain wall effects to Berry phase and demonstrating enhanced magnetoresistance.

Findings

Hall magnetoresistance is an order of magnitude larger than in conventional materials.

The effect is explained by a multi-domain model and a formula linking it to Berry phase.

The phenomenon enables potential multi-resistance-state modulation.

Abstract

Magnetic topological semimetals exhibit emerging magneto-transport behaviors, such as the giant anomalous Hall effect (AHE), chiral Hall effect, and antisymmetric magnetoresistance. In this work, based on the magnetic Weyl semimetal Co3Sn2S2, we report an intriguing longitudinal domain-wall Hall magnetoresistance in multi-domain states. According to a multi-domain model, a concise formula of this Hall magnetoresistance was revealed and verified experimentally. Rather than the real change of longitudinal resistance, this Hall magnetoresistance originates from an additional electric field distribution induced by the transverse giant AHE through the domain wall, which can be directly correlated to the Berry phase of topological Weyl bands. In Co3Sn2S2 devices, the Hall magnetoresistance was an order of magnitude larger than that of conventional magnetic materials, indicating its potential for multi-resistance-state modulation via the Weyl-enhanced AHE.