Coupled Spin and Pseudo-magnetic Field in Graphene Nanoribbons

Abstract

Pseudo-magnetic field becomes an experimental reality after the observation of zero-field Landau level-like quantization in strained graphene, but it is not expected that the time-reversal symmetric pseudo-magnetic fields will have any effect on the spin degree of freedom of the charge carriers. Here, we demonstrate that spin-orbit coupling (SOC) could act as a bridge between pseudo-magnetic field and spin. In quantum spin Hall (QSH) states, the direction of the spin of edge states is tied to their direction of motion because of the SOC. The pseudo-magnetic field affects the clockwise and counter-clock-wise edge currents of the QSH states, and consequently lifts the degenerate edge states of opposite spin orientation. Because of opposite signs of the pseudo-magnetic field in two valleys of graphene, the one-dimensional charge carriers at the two opposite edges have different group velocities, and in some special cases the edge states can only propagate at one edge of the nanoribbon and the group velocity at the other edge becomes zero.

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Cited by in corpus (12)

• Hierarchy of Graphene Wrinkles Induced by Thermal Strain Engineering
• Dispersive Landau levels and valley currents in strained graphene nanoribbons
• Creating Magnetic Fields in excess of 1000 T by Misoriented Stacking in a Graphene Bilayer
• Effective Dirac Hamiltonian for anisotropic honeycomb lattices: optical properties
• Elastic Gauge Fields and Hall Viscosity of Dirac Magnons
• Phase diagrams and edge-state transitions in graphene with spin-orbit coupling and magnetic and pseudomagnetic fields
• Reverse strain-induced snake states in graphene nanoribbons
• Quantum Monte Carlo study of honeycomb antiferromagnets under a triaxial strain
• Complex Landau levels and related transport properties in the strained zigzag graphene nanoribbons
• Fractional Josephson effect in nonuniformly strained graphene
• Helical superconducting edge modes from pseudo-Landau levels in graphene
• Generation of Half-Integer Harmonics and Efficient THz-to-Visible Frequency Conversion in Strained Graphene