An extended defect in graphene as a metallic wire

TLDR: The realization of a one-dimensional topological defect in graphene, containing octagonal and pentagonal sp(2)-hybridized carbon rings embedded in a perfect graphene sheet is reported, which acts as a quasi-one-dimensional metallic wire.

Abstract: Many proposed applications of graphene require the ability to tune its electronic structure at the nanoscale1,2. Although charge transfer3 and field-effect doping4 can be applied to manipulate charge carrier concentrations, using them to achieve nanoscale control remains a challenge. An alternative approach is ‘self-doping’5, in which extended defects are introduced into the graphene lattice. The controlled engineering of these defects represents a viable approach to creation and nanoscale control of one-dimensional charge distributions with widths of several atoms6. However, the only experimentally realized extended defects so far have been the edges of graphene nanoribbons7,8,9,10, which show dangling bonds that make them chemically unstable11,12,13. Here, we report the realization of a one-dimensional topological defect in graphene, containing octagonal and pentagonal sp2-hybridized carbon rings embedded in a perfect graphene sheet. By doping the surrounding graphene lattice, the defect acts as a quasi-one-dimensional metallic wire. Such wires may form building blocks for atomic-scale, all-carbon electronics. A stable extended defect in graphene consisting of octagonal and pentagonal rings produces one-dimensional charge localization, allowing it to act as a metallic wire embedded in an otherwise perfect graphene sheet.