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arXiv · 0902.1638

Graphene on the C-terminated SiC (000 $\bar{1}$) surface: An ab initio study

L. Magaud·F. Hiebel·F. Varchon·P. Mallet·J. -Y. Veuillen
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Abstract

The atomic and electronic structures of a graphene layer on top of the $(2\times2)$ reconstruction of the SiC (000$\bar{1}$) surface are studied from ab initio calculations. At variance with the (0001) face, no C bufferlayer is found here. Si adatoms passivate the substrate surface so that the very first C layer presents a linear dispersion characteristic of graphene. A small graphene-substrate interaction remains in agreement with scanning tunneling experiments (F.Hiebel et al. {\it Phys. Rev. B} {\bf 78} 153412 (2008)). The stacking geometry has little influence on the interaction which explains the rotational disorder observed on this face.

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L. Magaud, F. Hiebel, F. Varchon, P. Mallet, J. -Y. Veuillen. 2009-02-10. Graphene on the C-terminated SiC (000 $\bar{1}$) surface: An ab initio study. https://doi.org/10.1103/physrevb.79.161405

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