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arXiv · 1107.0085

Three-Fold Diffraction Symmetry in Epitaxial Graphene and the SiC Substrate

David A. Siegel·Shuyun Zhou·Farid El Gabaly·Andreas K. Schmid·Kevin F. McCarty·Alessandra Lanzara
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Abstract

The crystallographic symmetries and spatial distribution of stacking domains in graphene films on SiC have been studied by low energy electron diffraction (LEED) and dark field imaging in a low energy electron microscope (LEEM). We find that the graphene diffraction spots from 2 and 3 atomic layers of graphene have 3-fold symmetry consistent with AB (Bernal) stacking of the layers. On the contrary, graphene diffraction spots from the buffer layer and monolayer graphene have apparent 6-fold symmetry, although the 3-fold nature of the satellite spots indicates a more complex periodicity in the graphene sheets.

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David A. Siegel, Shuyun Zhou, Farid El Gabaly, Andreas K. Schmid, Kevin F. McCarty, Alessandra Lanzara. 2011-06-30. Three-Fold Diffraction Symmetry in Epitaxial Graphene and the SiC Substrate. https://doi.org/10.1103/physrevb.80.241407

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