Protected pseudohelical edge states in proximity graphene ribbons and flakes

Abstract

We investigate topological properties of models that describe graphene on realistic substrates which induce proximity spin-orbit coupling in graphene. A ${\mathbb{Z}}_2$ phase diagram is calculated for the parameter space of (generally different) intrinsic spin-orbit coupling on the two graphene sublattices, in the presence of Rashba coupling. The most fascinating case is that of staggered intrinsic spin-orbit coupling which, despite being topologically trivial, ${\mathbb{Z}}_2=0$, does exhibit edge states protected against time-reversal scattering for zigzag ribbons as wide as micrometers. We call these states pseudohelical as their helicity is locked to the sublattice. The spin character and robustness of the pseudohelical modes is best exhibited on a finite flake, which shows that the edge states have zero $g$-factor, carry a finite spin current in the crossection of the flake, and exhibit spin-flip reflectionless tunneling at the armchair edges.

10 pages, 9 figures, 1 video

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Cited by in corpus (49)

• Van der Waals heterostructures for spintronics and opto-spintronics
• Quantum Anomalous Hall Effects in Graphene from Proximity-Induced Uniform and Staggered Spin-Orbit and Exchange Coupling
• Induced spin-orbit coupling in twisted graphene-TMDC heterobilayers: twistronics meets spintronics
• Twist-angle dependent proximity induced spin-orbit coupling in graphene/transition-metal dichalcogenide heterostructures
• Connecting Higher-Order Topology with the Orbital Hall Effect in Monolayers of Transition Metal Dichalcogenides
• Spin-Orbit Interaction Induced in Graphene by Transition-Metal Dichalcogenides
• Twist- and gate-tunable proximity spin-orbit coupling, spin relaxation anisotropy, and charge-to-spin conversion in heterostructures of graphene and transition-metal dichalcogenides
• Tunable spin-polarized edge currents in proximitized transition metal dichalcogenides
• Testing Topological Protection of Edge States in Hexagonal Quantum Spin Hall Candidate Materials
• Tunable Circular Dichroism and Valley Polarization in the Modified Haldane Model
• Counterintuitive gate dependence of weak antilocalization in bilayer graphene/WSe${}_2$ heterostructures
• Proximity effects in graphene on monolayers of transition-metal phosphorus trichalcogenides MPX${}_3$
• Heterostructures of graphene and topological insulators Bi${}_2$Se${}_3$, Bi${}_2$Te${}_3$, and Sb${}_2$Te${}_3$
• Antiferromagnetic spin valve from heterostructure of two-dimensional hexagonal crystals
• Single and bilayer graphene on the topological insulator Bi${}_2$Se${}_3$: Electronic and spin-orbit properties from first principles
• Topological phases and twisting of graphene on a dichalcogenide monolayer
• Proximity-induced topological phases in bilayer graphene
• Twist-angle dependent proximity induced spin-orbit coupling in graphene/topological insulator heterostructures
• Chiral Majorana fermions in graphene from proximity-induced superconductivity
• Large spin-relaxation anisotropy in bilayer-graphene/WS${}_2$ heterostructures
• Spin-orbit-enhanced robustness of supercurrent in graphene/WS${}_2$ Josephson junctions
• Perfect crossed Andreev reflection in the proximitized graphene/superconductor/proximitized graphene junctions
• Volkov-Pankratov states in topological graphene nanoribbons
• Topological edge states of a graphene zigzag nanoribbon with spontaneous edge magnetism
• Two-Dimensional Higher-Order Topological Metals
• DFT2kp: effective kp models from ab-initio data
• Two-dimensional Weyl nodal-line semimetal and antihelical edge states in a modified Kane-Mele model
• Stacking-induced Chern insulator
• Effect of proximity-induced spin-orbit coupling in graphene mesoscopic billiards
• Reversible edge spin currents in antiferromagnetically proximitized dichalcogenides
• Proximity-enhanced valley Zeeman splitting at the WS${}_2$/graphene interface
• Dispersive 1D Majorana modes with emergent supersymmetry in 1D proximitized superconductors via spatially-modulated potentials and magnetic fields
• Tuning of Bilayer Graphene Heterostructure by Horizontally Incident Circular Polarized Light
• Proximity-induced spin-polarized magnetocaloric effect in transition metal dichalcogenides
• Landau levels in spin-orbit coupling proximitized graphene: bulk states
• Floquet states of Valley-Polarized Metal with One-way Spin or Charge Transport in Zigzag Nanoribbons
• Robust propagating in-gap modes due to spin-orbit domain walls in graphene
• Tunable Kondo resonance at a pristine two-dimensional Dirac semimetal on a Kondo insulator
• Edge states in proximitized graphene ribbons and flakes in a perpendicular magnetic field: emergence of lone pseudohelical pairs and pure spin-current states
• Valley-dependent transport through graphene quantum dots due to proximity-induced, staggered spin-orbit couplings
• Topological characterization of modified Kane-Mele-Rashba models via local spin Chern marker
• Zigzag nanoribbon of gated bilayer hexagonal crystals with spontaneous edge magnetism
• Ultra-Fast All-Electrical Universal Nano-Qubits
• Dirac-Rashba fermions and quantum valley Hall insulators in graphene-based 2D heterostructures
• The emergence of interface states in graphene/transition metal dichalcogenides heterostructure with lateral interface
• Proximity spin-orbit coupling in graphene on alloyed transition metal dichalcogenides
• Valley-Polarized Quantum Anomalous Hall Phase in Bilayer Graphene with Layer-Dependent Proximity Effects
• Intra-band and Inter-band Plasmons in Transition Metal Dichalcogenide-Graphene van der Waals Heterostructures
• Optical properties of van der Waals heterostructure of uniaxially strained graphene on TMD