Spin Polarized and Valley Helical Edge Modes in Graphene Nanoribbons

Abstract

Inspired by recent progress in fabricating precisely zigzag-edged graphene nanoribbons and the observation of edge magnetism, we find that spin polarized edge modes with well-defined valley index can exist in a bulk energy gap opened by a staggered sublattice potential such as that provided by a hexagonal Boron-Nitride substrate. Our result is obtained by both tight-binding model and first principles calculations. These edge modes are helical with respect to the valley degree of freedom, and are robust against scattering, as long as the disorder potential is smooth over atomic scale, resulting from the protection of the large momentum separation of the valleys.

4 pages, 4 figures

References in corpus (17)

• Electric Field Effect in Atomically Thin Carbon Films
• The electronic properties of graphene
• Half-Metallic Graphene Nanoribbons
• Substrate-induced band gap opening in epitaxial graphene
• Valley filter and valley valve in graphene
• Andreev reflection and Klein tunneling in graphene
• Spatially Resolving Spin-split Edge States of Chiral Graphene Nanoribbons
• Phase Coherent Transport of Charges in Graphene Quantum Billiard
• Topological confinement in bilayer graphene
• Anisotropic Etching and Nanoribbon Formation in Single-Layer Graphene
• Edge states in Graphene: from gapped flat band to gapless chiral modes
• Quantum Anomalous Hall Effect in Single-layer and Bilayer Graphene
• Electronic transport properties of graphene nanoribbons
• Scattering universality classes of side jump in anomalous Hall effect
• Marginality of bulk-edge correspondence for single-valley Hamiltonians
• Universal quantized spin-Hall conductance fluctuation in graphene
• Non-local exchange effects in zigzag edge magnetism of neutral graphene nanoribbons

Cited by in corpus (16)

• Topological Phases in Two-Dimensional Materials: A Brief Review
• Valley-Hall Kink and Edge States in Multilayer Graphene
• Topological Kirchhoff Law and Bulk-Edge Correspondence for Valley-Chern and Spin-Valley-Chern Numbers
• Insulating nature of strongly correlated massless Dirac fermions in an organic crystal
• Helicoidal Graphene Nanoribbons: Chiraltronics
• Interplay between sublattice and spin symmetry breaking in graphene
• Gate-induced Dirac cones in multilayer graphenes
• The role of geometry and topological defects in the 1D zero-line modes of graphene
• Unbalanced edge modes and topological phase transition in gated trilayer graphene
• Band bending and zero-conductance resonances controlled by edge electric fields in zigzag silicene nanoribbons
• Magnetic Impurity Affected by Spin-Orbit Coupling: Behavior near a Topological Phase Transition
• Effects of disorder on electron tunneling through helical edge states
• Effectuating tunable valley selection via multi-terminal monolayer graphene devices
• Diffusion on edges of insulating graphene with intravalley and intervalley scattering
• Tuning the electronic structure and magnetic coupling in armchair B${}_2$S nanoribbons using strain and staggered sublattice potential
• Topological Interface States and Nonlinear Thermoelectric Performance in Armchair Graphene Nanoribbon Heterostructures