Proximity-induced negative magnetoresistance and anomalous Hall effect in monolayer graphene/CrSBr heterojunctions

The integration of graphene with magnetic insulators to invoke the magnetic proximity effect provides a powerful route toward spintronic devices that preserve graphene’s exceptional transport characteristics. A persistent challenge, however, is the identification of magnetic substrates that are both air-stable and capable of forming high-quality van der Waals interfaces. Here, we present a magnetotransport investigation of monolayer graphene coupled to a layered A-type antiferromagnetic semiconductor CrSBr nanoflake, which is notable for its high Néel temperature (∼132 K) and outstanding environmental stability. High-quality heterojunctions are obtained via a dry-transfer technique to ensure an atomically clean interface. Pronounced negative magnetoresistance and anomalous Hall effect in graphene are observed, arising from the suppression of spin-disorder scattering induced by the proximity exchange field from the CrSBr layer. Moreover, the heterojunction exhibits clear two-frequency Shubnikov–de Haas oscillations, evidencing the emergence of Fermi surface reconstruction in the monolayer graphene. Our results demonstrate that antiferromagnetic CrSBr can impose a robust magnetic proximity effect that manipulates the spin degrees of freedom in graphene, opening new opportunities for spintronic functionalities in two-dimensional materials.