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arXiv · 0907.5222

First direct observation of a nearly ideal graphene band structure

M. Sprinkle·D. Siegel·Y. Hu·J. Hicks·P. Soukiassian·A. Tejeda·A. Taleb-Ibrahimi·P. Le Fèvre·F. Bertran·C. Berger·W. A. de Heer·A. Lanzara·E. H. Conrad
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Abstract

Angle-resolved photoemission and X-ray diffraction experiments show that multilayer epitaxial graphene grown on the SiC(000-1) surface is a new form of carbon that is composed of effectively isolated graphene sheets. The unique rotational stacking of these films cause adjacent graphene layers to electronically decouple leading to a set of nearly independent linearly dispersing bands (Dirac cones) at the graphene K-point. Each cone corresponds to an individual macro-scale graphene sheet in a multilayer stack where AB-stacked sheets can be considered as low density faults.

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M. Sprinkle, D. Siegel, Y. Hu, J. Hicks, P. Soukiassian, A. Tejeda, A. Taleb-Ibrahimi, P. Le Fèvre, F. Bertran, C. Berger, W. A. de Heer, A. Lanzara, E. H. Conrad. 2009-07-30. First direct observation of a nearly ideal graphene band structure. https://doi.org/10.1103/physrevlett.103.226803

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