Electronic structure of epitaxial graphene nanoribbons on SiC(0001)

I. Deretzis; A. La Magna

doi:10.1063/1.3202397

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arXiv · 0908.2554

Electronic structure of epitaxial graphene nanoribbons on SiC(0001)

I. Deretzis·A. La Magna

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Abstract

We present electronic structure calculations of few-layer epitaxial graphene nanoribbons on SiC(0001). Trough an atomistic description of the graphene layers and the substrate within the extended Hückel Theory and real/momentum space projections we argue that the role of the heterostructure's interface becomes crucial for the conducting capacity of the studied systems. The key issue arising from this interaction is a Fermi level pinning effect introduced by dangling interface bonds. Such phenomenon is independent from the width of the considered nanostructures, compromising the importance of confinement in these systems.

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I. Deretzis, A. La Magna. 2009-08-18. Electronic structure of epitaxial graphene nanoribbons on SiC(0001). https://doi.org/10.1063/1.3202397

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