Quantum Hall phase in graphene engineered by interfacial charge coupling

Abstract

Quantum Hall effect (QHE), the ground to construct modern conceptual electronic systems with emerging physics, is often much influenced by the interplay between the host two-dimensional electron gases and the substrate, sometimes predicted to exhibit exotic topological states. Yet the understanding of the underlying physics and the controllable engineering of this paradigm of interaction remain challenging. Here we demonstrate the observation of an unusual QHE, which differs markedly from the known picture, in graphene samples in contact with an anti-ferromagnetic insulator CrOCl equipped with dual gates. Owing to the peculiar interfacial coupling, Landau levels in monolayer graphene remain intact at negative filling fractions, but largely deviated for the positive gate-doping range. The latter QHE phase even presents in the limit of zero magnetic field, with the consequential Landau quantization following a parabolic relation between the displacement field $D$ and the magnetic field $B$. This characteristic prevails up to 100 K in a sufficiently wide effective doping range from 0 to 10${}^{13}$ cm${}^{-2}$. Our findings thus open up new routes for manipulating the quantum electronic states, which may find applications in such as quantum metrology.

11 pages, 5 figures

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Cited by in corpus (11)

• Multi-state data storage in a two-dimensional stripy antiferromagnet implemented by magnetoelectric effect
• A seamless graphene spin valve based on proximity to van der Waals magnet Cr${}_2$Ge${}_2$Te${}_6$
• Designing topology and fractionalization in narrow gap semiconductor films via electrostatic engineering
• Synergistic correlated states and nontrivial topology in coupled graphene-insulator heterostructures
• Dissipation and dephasing in quantum Hall interferometers
• Gate-tunable spin Hall effect in trilayer graphene/group-IV monochalcogenide van der Waals heterostructures
• Constructing the Fulde-Ferrell-Larkin-Ovchinnikov state in antiferromagnetic insulator CrOCl
• Exploring the interfacial coupling between graphene and the antiferromagnetic insulator MnPSe${}_3$
• Gate control of 2D magnetism in tri- and four-layers $\mathrm{Cr}{\mathrm{I}}_3$/graphene heterostructures
• Spin and Valley Polarized Multiple Fermi Surfaces of α-RuCl${}_3$/Bilayer Graphene Heterostructure
• Pronounced scale-dependent charge carrier density in graphene quantum Hall devices