Year: 2007
Type: article
Abstract: Employing density-functional calculations we study single and double graphene layers on Si- and C-terminated 1x1-6H-SiC surfaces. We show that, in contrast with earlier assumptions, the first carbon layer is covalently bonded to the substrate and cannot be responsible for the graphene-type electronic spectrum observed experimentally. The characteristic spectrum of freestanding graphene appears with the second carbon layer, which exhibits a weak van der Waals bonding to the underlying structure. For Si-terminated substrate, the interface is metallic, whereas on C face it is semiconducting or semimetallic for single or double graphene coverage, respectively.
Source: Physical Review Letters
Authors: Alexander Mattausch, Oleg Pankratov
Institution: Friedrich-Alexander-Universität Erlangen-Nürnberg
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2033745067