Proximity induced charge transfer and anomalous temperature dependency in G/α-RuCl₃

Proximity effects in van der Waals heterostructures have proven to be a powerful means to induce a wide range of interfacial phenomena. Among van der Waals materials, α-RuCl₃ has attracted attention as a candidate platform to host the sought-after Kitaev quantum spin liquid phase owing to its frustrated spin interactions on the honeycomb lattice. However, due to strong Mott insulating behavior, probing electronic and magnetic properties of α-RuCl₃ using transport measurements is not possible. In this presentation, I will discuss graphene/α-RuCl₃ heterostructures as a novel platform for mutually altering the electronic properties of both graphene and α-RuCl₃. Quantum oscillations and Hall measurements provide clear evidence for a band realignment that is accompanied by a large transfer of electrons originally occupying the graphene’s spin degenerate Dirac cones into α-RuCl₃ band with in-plane spin polarization. Furthermore, the temperature dependent measurements of the quantum oscillations reveal a non-Lifshitz-Kosevich behavior. The origin of this anomalous temperature behavior is studied by varying the thickness of the α-RuCl₃ layer, point to an interplay with the underlying delicate magnetic texture of the material in the thin-limit.