Quantum Hall states in spin-orbit proximitized monolayer graphene

Spin-orbit coupling (SOC) provides a potential route to controlling spin in devices as well as realizing topological electronic ground states [1]. Graphene/TMDs heterostructures have emerged as a suitable candidate for such devices due to the outstanding electron and spin transport properties as well as the proximity-enabled spin-orbit effects [2, 3]. In this work we use transport measurements to probe quantum Hall ground states in graphene/WSe₂ heterobilayers. At low temperature in a perpendicular magnetic field B, we observe all symmetry-broken integer quantum Hall states, yielding spin and valley information. The measured thermal activation gaps at half-filled quartets show significantly different B-dependence for electron or hole doping, deviating from the isolated graphene behavior. We attribute this observation to the proximity-induced SOC, to quantitatively extract the SOC strength, we are developing a self-consistent Hartree-Fock model incorporating Ising and Rashba SOC along with Coulomb interactions. Our work provides insight into the interplay of SOC and interactions in this fascinating system.

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