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arXiv · 0706.2134

Rotational stacking and its electronic effects on graphene films grown on 4H-SiC$(000\bar{1})$

J. Hass·F. Varchon·J. E. Millan-Otoya·M. Sprinkle·W. A. de Heer·C. Berger·P. N. First·L. Magaud·E. H. Conrad
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Abstract

We examine the stacking order of multilayer graphene grown on the SiC$(000\bar{1})$ surface using low-energy electron diffraction and surface X-ray diffraction. We show that the films contain a high density of rotational stacking faults caused by three types of rotated graphene: sheets rotated $30^\circ$ and $\pm 2.20^\circ$ relative to the SiC substrate. These angles are unique because they correspond to commensurate phases of layered graphene, both with itself and with the SiC substrate. {\it Ab intio} calculations show that these rotational phases electronically decouple adjacent graphene layers. The band structure from graphene at fault boundaries displays linear energy dispersion at the $K$-point (Dirac cones), nearly identical to that of a single graphene sheet.

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J. Hass, F. Varchon, J. E. Millan-Otoya, M. Sprinkle, W. A. de Heer, C. Berger, P. N. First, L. Magaud, E. H. Conrad. 2007-06-14. Rotational stacking and its electronic effects on graphene films grown on 4H-SiC$(000\bar{1})$. https://arxiv.org/abs/0706.2134

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