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Preliminary results on these ribbons are very promising. Photoemission has allowed us to observe that at the edge of these graphene strips, a semiconductor, is bonded to metallic graphene. This semiconductor is only a few nanometers wide (a few graphene lattice constants), a level of precision beyond modern lithographic limits.
To learn more.:
« A wide band gap metal-semiconductor-metal nanostructure made entirely from graphene ».
J. Hicks, A. Tejeda, A. Taleb-Ibrahimi, M.S. Nevius, F. Wang, K. Shepperd, J. Palmer, F. Bertran, P. Le Fèvre, J. Kunc, W.A. de Heer, C. Berger, et E.H. Conrad.
Nature Physics 9, 49 (2012). Link to article.