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Band Structure and Energy Level Alignment of Chiral Graphene Nanoribbons on Silver Surfaces.

ABSTRACT: Chiral graphene nanoribbons are extremely interesting structures due to their narrow band gaps and potential development of spin-polarized edge states. Here, we study their band structure on low work function silver surfaces. The use of a curved Ag single crystal provides, within the same sample, regions of disparate step structure and step density. Whereas the former leads to distinct azimuthal growth orientations of the graphene nanoribbons atop, the latter modulates the substrate's work function and thereby the interface energy level alignment. In turn, we disclose the associated charge transfer from the substrate to the ribbon and assess its effect on the nanoribbon's properties and the edge state magnetization.

SUBMITTER: Corso M

PROVIDER: S-EPMC8705322 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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Band Structure and Energy Level Alignment of Chiral Graphene Nanoribbons on Silver Surfaces.

Corso Martina M Menchón Rodrigo E RE Piquero-Zulaica Ignacio I Vilas-Varela Manuel M Ortega J Enrique JE Peña Diego D Garcia-Lekue Aran A de Oteyza Dimas G DG

Nanomaterials (Basel, Switzerland) 20211206 12

Chiral graphene nanoribbons are extremely interesting structures due to their narrow band gaps and potential development of spin-polarized edge states. Here, we study their band structure on low work function silver surfaces. The use of a curved Ag single crystal provides, within the same sample, regions of disparate step structure and step density. Whereas the former leads to distinct azimuthal growth orientations of the graphene nanoribbons atop, the latter modulates the substrate's work funct ...[more]

PMID: 34947652

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