Why multilayer graphene on 4H-SiC(0001[over ]) behaves like a single sheet of graphene.

The Georgia Institute of Technology, Atlanta, Georgia 30332-0430, USA.
Physical Review Letters (Impact Factor: 7.73). 03/2008; 100(12):125504. DOI: 10.1103/PhysRevLett.100.125504
Source: PubMed

ABSTRACT We show experimentally that multilayer graphene grown on the carbon terminated SiC(0001[over ]) surface contains rotational stacking faults related to the epitaxial condition at the graphene-SiC interface. Via first-principles calculation, we demonstrate that such faults produce an electronic structure indistinguishable from an isolated single graphene sheet in the vicinity of the Dirac point. This explains prior experimental results that showed single-layer electronic properties, even for epitaxial graphene films tens of layers thick.

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