Proximity-Induced Ferromagnetism in Graphene Revealed by the Anomalous Hall Effect

We demonstrate the anomalous Hall effect (AHE) in single-layer graphene exchange coupled to an atomically flat yttrium iron garnet (YIG) ferromagnetic thin film. The anomalous Hall conductance has magnitude of ∼0.09(2e2/h) at low temperatures and is measurable up to ∼300 K. Our observations indicate not only proximity-induced ferromagnetism in graphene/YIG with a large exchange interaction, but also enhanced spin-orbit coupling that is believed to be inherently weak in ideal graphene. The proximity-induced ferromagnetic order in graphene can lead to novel transport phenomena such as the quantized AHE which are potentially useful for spintronics.Received 28 May 2014DOI:https://doi.org/10.1103/PhysRevLett.114.016603© 2015 American Physical Society