Conductance modulation in graphene/antiferromagnet van der Waals heterostructures induced by magnetic order

Abstract

Two-dimensional (2D) van der Waals (vdW) antiferromagnets (AFMs) have emerged as promising candidates for spintronic applications due to their fast spin dynamics and robustness against external magnetic perturbations. However, their intrinsically low electrical conductivity challenges their integration into electronic devices. A possible path to overcome this limitation is to form vdW heterostructures with highly conductive materials such as graphene, which can sensitively respond to interfacial magnetic interactions. Such an interplay is, however, far from being understood. In this work, we investigate vdW heterostructures composed of single-layer graphene and the antiferromagnet FePS₃ (FEPS). Electron transport measurements in a field-effect transistor geometry reveal a sharp change in graphene resistance precisely at the Néel temperature of FEPS. Temperature-dependent Raman spectroscopy and gate-dependent transport suggest a distinct interfacial charge transfer driven by the antiferromagnetic ordering. Density functional theory (DFT) calculations support this mechanism, showing a significant modulation of charge transfer across the interface linked to the magnetic phase. These findings unveil a strong interplay between magnetism and electron transport in 2D vdW heterostructures and pave the way toward integrating antiferromagnetic vdW materials into future electronic and spintronic technologies.