1212.4309 (M. Ridene et al.)

Epitaxial Graphene Nanoribbons on Bunched Steps of a 6H-SiC(0001)
Substrate: Aromatic Ring Pattern and Van Hove Singularities    [PDF]

M. Ridene, T. Wassmann, E. Pallecchi, G. Rodary, J. C. Girard, A. Ouerghi1

We report scanning tunneling microscopy and spectroscopy investigation of graphene nanoribbons grown on an array of bunched steps of a 6H-SiC(0001) substrate. Our scanning tunneling microscopy images of a graphene nanoribbons on a step terrace feature a (sqrt(3)x sqrt(3))R30{\deg} pattern of aromatic rings which define our armchair nanoribbons. This is in agreement to a simulation based on density functional theory. As another signature of the one-dimensional electronic structure, in the corresponding scanning tunneling spectroscopy spectra we find well developed, sharp Van Hove singularities.

View original: http://arxiv.org/abs/1212.4309