Spontaneous breakdown of topological protection in two dimensions

Abstract

Due to time-reversal symmetry (TRS), two dimensional topological insulators support counter-propagating helical edge modes. Here we show that, unlike the infinitely sharp edge potential utilized in traditional calculations, an experimentally more realistic smooth edge potential gives rise to edge reconstruction and, consequently, spontaneous TRS breaking. Such edge reconstruction may lead to breaking of the expected perfect conductance quantization, to a finite Hall resistance at zero magnetic field, and to a likely spin current. This calculation underpins the fragility of the topological protection in realistic systems, which is of crucial importance in proposed applications.

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Cited by in corpus (54)

• Josephson radiation from gapless Andreev bound states in HgTe-based topological junctions
• Transport in two-dimensional topological materials: recent developments in experiment and theory
• Interacting topological edge channels
• Failure of conductance quantization in two-dimensional topological insulators due to non-magnetic impurities
• Effects of nuclear spins on the transport properties of the edge of two-dimensional topological insulators
• Exact solution of single impurity problem in non-reciprocal lattices: impurity induced size-dependent non-Hermitian skin effect
• Edge states reconstruction from strong correlations in quantum spin Hall insulators
• Helical Liquids in Semiconductors
• Fractional Edge Reconstruction in Integer Quantum Hall Phases
• Indirect exchange interaction between magnetic impurities near the helical edge
• Mesoscopic transport in two-dimensional topological insulators
• Topological protection brought to light by the time-reversal symmetry breaking
• Helical edge transport in the presence of a magnetic impurity
• Dynamical separation of bulk and edge transport in HgTe-based 2D topological insulators
• Nontrivial interplay of strong disorder and interactions in quantum spin-Hall insulators doped with dilute magnetic impurities
• Spontaneously broken translational symmetry at edges of high-temperature superconductors: thermodynamics in magnetic field
• Helical edge transport in the presence of a magnetic impurity: the role of local anisotropy
• Two-dimensional topological insulator state in double HgTe quantum well
• Signatures of dephasing by mirror-symmetry breaking in weak-antilocalization magnetoresistance across the topological transition in Pb${}_{1-x}$Sn${}_x$Se
• Unrestricted electron bunching at the helical edge
• Microwave studies of the fractional Josephson effect in HgTe-based Josephson junctions
• Quantitative theory of backscattering in topological HgTe and (Hg,Mn)Te quantum wells: acceptor states, Kondo effect, precessional dephasing, and bound magnetic polaron
• Spin Mode-Switching at the Edge of a Quantum Hall System
• Emergence of Neutral Modes in Laughlin-like Fractional Quantum Hall Phases
• Phase Crystals
• Edge stability and edge quantum criticality in 2D interacting topological insulators
• Manipulating topological-insulator properties using quantum confinement
• Coherent-Incoherent Crossover of Charge and Neutral Mode Transport as Evidence for the Disorder-Dominated Fractional Edge Phase
• Magnetic field dependent equilibration of fractional quantum Hall edge modes
• Breakdown of topological protection due to non-magnetic edge disorder in two-dimensional materials in the Quantum Spin Hall phase
• Finite frequency backscattering current noise at a helical edge
• Edge States in Lateral p-n Junctions in Inverted Band HgTe Quantum Wells
• Tomonaga Luttinger liquid in the topological edge channel of multilayer FeSe
• Protection of Edge transport in Quantum Spin Hall samples: Spin-Symmetry Based General Approach and Examples
• Multi-frequency Shubnikov-de Haas oscillations in topological semimetal Pt${}_2$HgSe${}_3$
• Josephson radiation from nonlinear dynamics of Majorana zero modes
• Analytical and Numerical study of the out-of-equilibrium current through a helical edge coupled to a magnetic impurity
• Velocity and confinement of edge plasmons in HgTe-based 2D topological insulators
• Reconstruction-Induced ${\phi }_0$ Josephson Effect in Quantum Spin Hall Constrictions
• Multiple Mechanisms for Emerging Conductance Plateaus in Fractional Quantum Hall States
• Edge Reconstruction of a Time-Reversal Invariant Insulator: Compressible-Incompressible Stripes
• Robustness of Helical Edge States Under Edge Reconstruction
• Conductance suppression by nonmagnetic point defects in helical edge channels of two-dimensional topological insulators
• Interplay between intrinsic and emergent topological protection on interacting helical modes
• Tunable helical crystals
• Topological and magnetic properties of the interacting Bernevig-Hughes-Zhang model
• Experimentally Motivated Order of Length Scales Affect Shot Noise
• Edge Reconstruction and Emergent Neutral Modes in Integer and Fractional Quantum Hall Phases
• Electronic thermal conductivity in 2D topological insulator in a HgTe quantum well
• Effective Hamiltonian of topologically protected qubit in a helical crystal
• Conductance resonances and crossing of the edge channels in the quantum Hall ferromagnet state of Cd(Mn)Te microstructures
• Sensing the binding and unbinding of anyons at impurities
• Strengthened correlations near [110] edges of $d$-wave superconductors in the t-J model with the Gutzwiller approximation
• Edge Reconstruction in a Quantum Spin Hall Insulator