Edge Disorder in Bottom-Up Zigzag Graphene Nanoribbons: Implications for Magnetism and Quantum Electronic Transport

Abstract

We unveil the nature of the structural disorder in bottom-up zigzag graphene nanoribbons along with its effect on the magnetism and electronic transport on the basis of scanning probe microscopies and first-principles calculations. We find that edge-missing m-xylene units emerging during the cyclodehydrogenation step of the on-surface synthesis are the most common point defects. These "bite'' defects act as spin-1 paramagnetic centers, severely disrupt the conductance spectrum around the band extrema, and give rise to spin-polarized charge transport. We further show that the electronic conductance across graphene nanoribbons is more sensitive to "bite" defects forming at the zigzag edges than at the armchair ones. Our work establishes a comprehensive understanding of the low-energy electronic properties of disordered bottom-up graphene nanoribbons.

References in corpus (9)

• Energy Gaps in Graphene Nanoribbons
• Half-Metallic Graphene Nanoribbons
• Emergence of magnetism in graphene materials and nanostructures
• Room temperature magnetic order on zigzag edges of narrow graphene nanoribbons
• Magnetic Correlations at Graphene Edges
• Atomic-scale control of graphene magnetism using hydrogen atoms
• Improvements on non-equilibrium and transport Green function techniques: the next-generation transiesta
• Spin currents in rough graphene nanoribbons: Universal fluctuations and spin injection
• Imprinting Tunable $\pi$-Magnetism in Graphene Nanoribbons via Edge Extensions

Cited by in corpus (1)

• Hydrogen Atoms on Zigzag Graphene Nanoribbons: Chemistry and Magnetism Meet at the Edge