The Coexistence and Decoupling of Bulk and Edge States in Disordered Two-dimensional Topological Insulators

Abstract

We investigate the scattering and localization properties of edge and bulk states in a disordered two-dimensional topological insulator when they coexist at the same fermi energy. Due to edge-bulk backscattering (which is not prohibited \emph{a priori} by topology or symmetry), Anderson disorder makes the edge and bulk states localized indistinguishably. Two methods are proposed to effectively decouple them and to restore robust transport. The first kind of decouple is from long range disorder, since edge and bulk states are well separated in $k$ space. The second one is from an edge gating, owing to the edge nature of edge states in real space. The latter can be used to electrically tune a system between an Anderson insulator and a topologically robust conductor, i.e., a realization of a topological transistor.

arXiv comment5 pages, 4 figures

References in corpus (31)

• Topological Insulators
• Topological insulators and superconductors
• $Z_2$ Topological Order and the Quantum Spin Hall Effect
• Quantum Spin Hall Insulator State in HgTe Quantum Wells
• Experimental Observation of the Quantum Anomalous Hall Effect in a Magnetic Topological Insulator
• Discovery (theoretical prediction and experimental observation) of a large-gap topological-insulator class with spin-polarized single-Dirac-cone on the surface
• A topological Dirac insulator in a quantum spin Hall phase : Experimental observation of first strong topological insulator
• Low-energy effective Hamiltonian involving spin-orbit coupling in Silicene and Two-Dimensional Germanium and Tin
• Quantum interference and Klein tunneling in graphene heterojunctions
• Valley-Polarized Metals and Quantum Anomalous Hall Effect in Silicene
• Nonlocal edge state transport in the quantum spin Hall state
• Evidence of Klein tunneling in graphene p-n junctions
• Topological Insulator and Helical Zero Mode in Silicene under Inhomogeneous Electric Field
• Topological Anderson Insulator
• Finite size effects of helical edge states in HgTe/CdTe quantum wells
• Theory of the topological Anderson insulator
• Numerical study of the topological Anderson insulator in HgTe/CdTe quantum wells
• Perfectly Conducting Channel and Universality Crossover in Disordered Nano-Graphene Ribbons
• Conductance calculations for quantum wires and interfaces: mode matching and Green functions
• Anomalously large conductance fluctuations in weakly disordered graphene
• Surface Scattering via Bulk Continuum States in the 3D Topological Insulator Bi${}_2$Se${}_3$
• Topological Anderson insulator phenomena
• Reconciling Conductance Fluctuations and the Scaling Theory of Localization
• Spin-polarized current induced by a local exchange field in a silicene nanoribbon
• A topological look at the quantum spin Hall state
• Stabilization of Quantum Spin Hall Effect by Designed Removal of Time-Reversal Symmetry of Edge States
• Topological Insulator in the Presence of Spatially Correlated Disorder
• Bulk metals with helical surface states
• Algebraic and Geometric Mean Density of States in Topological Anderson Insulators
• Effects of surface-bulk hybridization in 3D topological `metals'
• Conductance Distribution in Disordered Quantum Wires with a Perfectly Conducting Channel

Cited by in corpus (11)

• Topological Phases in Two-Dimensional Materials: A Brief Review
• Transport in two-dimensional topological materials: recent developments in experiment and theory
• Valley-polarized quantum anomalous Hall phase and disorder induced valley-filtered chiral edge channels
• Surface-to-bulk scattering in topological insulator films
• Disorder Effects in Topological States -- Brief Review of the Recent Developments
• Single-edge transport in an InAs/GaSb quantum spin Hall insulator
• Perfect valley filter based on topological phase in disordered $\mathrm{Sb}$ Monolayer Heterostructure
• Stability of topological properties of bismuth (111) bilayer
• Emergent $Z_2$ Topological Invariant and Robust Helical Edge States in Two-Dimensional Topological Metals
• Chebyshev Polynomial Method to Landauer-Büttiker Formula of Quantum Transport in Nanostructures
• Transport through Quantum Anomalous Hall Bilayers with Lattice Mismatch