Evidence for topological proximity effect in graphene coupled to topological insulator

Abstract

The emergence of topological order in graphene is in great demand for the realization of quantum spin Hall states. Recently, it is theoretically proposed that the spin textures of surface states in topological insulator can be directly transferred to graphene by means of proximity effect. Here we report the observations of the topological proximity effect in the graphene-topological insulator Bi2Se3 heterojunctions via magnetotransport measurements. The coupling between the p_z orbitals of graphene and the p orbitals of surface states on the Bi2Se3 bottom surface can be enhanced by applying perpendicular negative magnetic field, resulting in a giant negative magnetoresistance at the Dirac point up to about -91%. An obvious resistivity dip in the transfer curve at the Dirac point is also observed in the hybrid devices, which is consistent with the theoretical predictions of the distorted Dirac bands with unique spin textures inherited from Bi2Se3 surface states.

References in corpus (29)

• Two-Dimensional Gas of Massless Dirac Fermions in Graphene
• Topological Insulators
• Topological insulators and superconductors
• Experimental Observation of Quantum Hall Effect and Berry's Phase in Graphene
• Quantum Spin Hall Effect in Graphene
• Discovery (theoretical prediction and experimental observation) of a large-gap topological-insulator class with spin-polarized single-Dirac-cone on the surface
• Electronic transport in two dimensional graphene
• Carrier transport in 2D graphene layers
• A self-consistent theory for graphene transport
• Spintronics and Pseudospintronics in Graphene and Topological Insulators
• Hexagonal Warping Effects in the Surface States of Topological Insulator Bi${}_2$Te${}_3$
• Non-saturating magnetoresistance in heavily disordered semiconductors
• Spin-Orbit Proximity Effect in Graphene
• Quantum Anomalous Hall Effect in Graphene Proximity Coupled to an Antiferromagnetic Insulator
• Strong interface-induced spin-orbit coupling in graphene on WS2
• Strong interfacial exchange field in the graphene/EuS heterostructure
• Giant topological insulator gap in graphene with 5d adatoms
• Charge Transport and Inhomogeneity near the Charge Neutrality Point in Graphene
• Graphene-based topological insulator with an intrinsic bulk band gap above room temperature
• Proximity effect in graphene-topological insulator heterostructures
• Stabilizing topological phases in graphene via random adsorption
• Proximity-induced giant spin-orbit interaction in epitaxial graphene on topological insulator
• Quantum spin Hall states in graphene interacting with WS${}_2$ or WSe${}_2$
• Model for a Macroscopically Disordered Conductor with an Exactly Linear High-Field Magnetoresistance
• Current-induced spin polarization in topological insulator-graphene heterostructures
• Gate-Tunable Tunneling Resistance in Graphene/Topological Insulator Vertical Junctions
• Proximity Enhanced Quantum Spin Hall State in Graphene
• Model for the magnetoresistance and Hall coefficient of inhomogeneous graphene
• Tunneling in graphene-topological insulator hybrid devices

Cited by in corpus (6)

• Spin Proximity Effects in Graphene/Topological Insulator Heterostructures
• Effective Interactions in a Graphene Layer Induced by the Proximity to a Ferromagnet
• Magic angle conditions for twisted 3D topological insulators
• Proximity-Induced Spin-Orbit Coupling in Graphene-Bi${}_{1.5}$Sb${}_{0.5}$Te${}_{1.7}$Se${}_{1.3}$ Heterostructures
• Landau quantization in buckled monolayer GaAs
• Universally optimizable strategy for magnetic gaps towards high-temperature quantum anomalous Hall states via magnetic-insulator/topological-insulator building-blocks