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arXiv · 1806.06559

Exploring interlayer Dirac cone coupling in commensurately rotated few-layer graphene on SiC(000-1)

C. Mathieu·E. H. Conrad·F. Wang·J. E. Rault·V. Feyer·C. M. Schneider·O. Renault·N. Barrett
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Abstract

We investigate electronic band-structure images in reciprocal space of few layer graphene epitaxially grown on SiC(000-1). In addition to the observation of commensurate rotation angles of the graphene layers, the k-space images recorded near the Fermi edge highlight structures originating from diffraction of the Dirac cones due to the relative rotation of adjacent layers. The 21.9{\deg} and 27{\deg} rotation angles between two sheets of graphene are responsible for a periodic pattern that can be described with a superlattice unit cells. The superlattice generates replicas of Dirac cones with smaller wave vectors, due to a Brillouin zone folding.

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C. Mathieu, E. H. Conrad, F. Wang, J. E. Rault, V. Feyer, C. M. Schneider, O. Renault, N. Barrett. 2018-06-18. Exploring interlayer Dirac cone coupling in commensurately rotated few-layer graphene on SiC(000-1). https://doi.org/10.1002/sia.5541

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