Limited robustness of edge magnetism in zigzag graphene nanoribbons with electrodes

Abstract

It is shown that apart from well-known factors, like temperature, substrate, and edge reconstruction effects, also the presence of external contacts is destructive for the formation of magnetic moments at the edges of graphene nanoribbons. The edge magnetism gradually decreases when graphene/electrode interfaces become more and more transparent for electrons. In addition to the graphene/electrode coupling strength, also the aspect ratio parameter, i.e. a width/length ratio of the graphene nanoribbon, is crucial for the suppression of edge magnetism. The present theory uses a tight-binding method, based on the mean-field Hubbard Hamiltonian for $\pi$ electrons, and the Green's function technique within the Landauer-Büttiker approach.

8 pages, 6 figures

References in corpus (5)

• Half-Metallic Graphene Nanoribbons
• Doping graphene with metal contacts
• Emergence of magnetism in graphene materials and nanostructures
• Spin currents in rough graphene nanoribbons: Universal fluctuations and spin injection
• Effect of the attachment of ferromagnetic contacts on the conductivity and giant magnetoresistance of graphene nanoribbons

Cited by in corpus (1)

• Giant Magnetoresistance in Bilayer Graphene Nanoflakes