Giant Domain-Wall Hall Magnetoresistance in Magnetic Topological Semimetal

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.