Nonlocal topological valley transport at large valley Hall angles

Abstract

Berry curvature hot spots in two-dimensional materials with broken inversion symmetry are responsible for the existence of transverse valley currents, which give rise to giant nonlocal dc voltages. Recent experiments in high-quality gapped graphene have highlighted a saturation of the nonlocal resistance as a function of the longitudinal charge resistivity ${\rho }_{\mathrm{c},xx}$, when the system is driven deep into the insulating phase. The origin of this saturation is, to date, unclear. In this work we show that this behavior is fully compatible with bulk topological transport in the regime of large valley Hall angles (VHAs). We demonstrate that, for a fixed value of the valley diffusion length, the dependence of the nonlocal resistance on ${\rho }_{\mathrm{c},xx}$ weakens for increasing VHAs, transitioning from the standard ${\rho }_{\mathrm{c},xx}^3$ power-law to a result that is independent of ${\rho }_{\mathrm{c},xx}$.

5 pages, 3 figures

References in corpus (5)

• The Valley Hall Effect in MoS2 Transistors
• Direct electronic measurement of the spin Hall effect
• Detecting Topological Currents in Graphene Superlattices
• Proximity-induced ferromagnetism in graphene revealed by anomalous Hall effect
• Giant Nonlocality near the Dirac Point in Graphene

Cited by in corpus (25)

• Transport in two-dimensional topological materials: recent developments in experiment and theory
• Linear Scaling Quantum Transport Methodologies
• Observation of the quantum valley Hall state in ballistic graphene superlattices
• Nonlinear anomalous photocurrents in Weyl semimetals
• Theory of plasmonic effects in nonlinear optics: the case of graphene
• Origin of nonlocal resistance in multiterminal graphene on hexagonal-boron-nitride: Fermi surface edge currents rather than Fermi sea topological valley currents
• Nonlinear Valley Hall Effect
• Viscous magnetoresistance of correlated electron liquids
• Topological Valley Currents in Bilayer Graphene/Hexagonal Boron Nitride Superlattices
• Bulk valley transport and Berry curvature spreading at the edge of flat bands
• Valley Hall Effect and Non-Local Resistance in Locally Gapped Graphene
• Valley Hall Effect and Nonlocal Transport in Strained Graphene
• Non-identical moiré twins in bilayer graphene
• Extrinsic Spin-Charge Coupling in Diffusive Superconducting Systems
• Valley current generation using biased bilayer graphene dots
• Tunable valley Hall effect in gate-defined graphene superlattices
• Anomalous Nonlocal Resistance and Spin-charge Conversion Mechanisms in Two-Dimensional Metals
• Topological valley currents via ballistic edge modes in graphene superlattices near the primary Dirac point
• Non-conservation of the valley density and its implications for the observation of the valley Hall effect
• Intrinsic torque on the orbital angular momentum in an electric field
• Control of Spin Diffusion and Suppression of the Hanle Effect by the Coexistence of Spin and Valley Hall Effects
• Theory of Nonlocal Transport from Nonlinear Valley Responses
• Valley Pumping via Edge States and the Nonlocal Valley Hall Effect in Two-Dimensional Semiconductors
• Tunable atomically enhanced moiré Berry curvatures in twisted triple bilayer graphene
• Intrinsic nonlinear valley Nernst effect