%0 Journal Article
%T Extraordinary epitaxial alignment of graphene islands on Au(111)
%A Joseph M. Wofford
%A Elena Starodub
%A Andrew L. Walter
%A Shu Nie
%A Aaron Bostwick
%A Norman C. Bartelt
%A Konrad Th¨ırmer
%A Eli Rotenberg
%A Kevin F. McCarty
%A Oscar D. Dubon
%J Physics
%D 2012
%I arXiv
%R 10.1088/1367-2630/14/5/053008
%X Pristine, single-crystalline graphene displays a unique collection of remarkable electronic properties that arise from its two-dimensional, honeycomb structure. Using in-situ low-energy electron microscopy, we show that when deposited on the (111) surface of Au carbon forms such a structure. The resulting monolayer, epitaxial film is formed by the coalescence of dendritic graphene islands that nucleate at a high density. Over 95% of these islands can be identically aligned with respect to each other and to the Au substrate. Remarkably, the dominant island orientation is not the better lattice-matched 30^{\circ} rotated orientation but instead one in which the graphene [01] and Au [011] in-plane directions are parallel. The epitaxial graphene film is only weakly coupled to the Au surface, which maintains its reconstruction under the slightly p-type doped graphene. The linear electronic dispersion characteristic of free-standing graphene is retained regardless of orientation. That a weakly interacting, non-lattice matched substrate is able to lock graphene into a particular orientation is surprising. This ability, however, makes Au(111) a promising substrate for the growth of single crystalline graphene films.
%U http://arxiv.org/abs/1202.0561v2