| AVS 58th Annual International Symposium and Exhibition | |
| Surface Science Division | Friday Sessions |
| Session SS-FrM |
| Session: | Surface Science on Graphene |
| Presenter: | Guy Le Lay, Aix Marseille Univ, CNRS-CINaM, France and CNR-ISM, Italy |
| Authors: | P. Vogt, Aix Marseille Univ, CNRS-CINaM, France and Technische Universität Berlin, Germany P. De Padova, CNR-ISM, Italy C. Quaresima, CNR-ISM, Italy J. Avila, Synchrotron SOLEIL, France E. Frantzeskakis, Synchrotron SOLEIL, France M.C. Asensio, Synchrotron SOLEIL, France B. Ealet, Aix Marseille Univ, CNRS-CINaM, France G. Le Lay, Aix Marseille Univ, CNRS-CINaM, France and CNR-ISM, Italy |
| Correspondent: | Click to Email |
We have just synthesized in Marseille silicene sheets [1], i.e., atom-thin two-dimensional graphene-like silicon layers with an in-plane Si-Si interatomic distance of 0.23 nm [2], upon in-situ epitaxial growth on silver (111) surfaces. The honeycomb atomic structure is revealed in Scanning Tunnelling Microscopy, while the long-range epitaxial order is confirmed by sharp 4x4 Low Energy Electron Diffraction patterns. Dirac cones at the K and K’ points of the silicene Brillouin zone, evidenced in High-Resolution Synchrotron Radiation Angle-Resolved PhotoElectron Spectroscopy measurements, point to massless relativistic fermions with a Fermi velocity of 1.3E6 m/s, as theoretically predicted [3], quite the same as graphene, and four times higher than previously obtained on a one-dimensional grating of silicene nano-ribbons [4]. Density Functional Theory calculations including the Ag(111) substrate confirm the stability of the epitaxial arrangement. The demonstration that silicon can form sheets of silicene, a two dimensional honeycomb structure, which does not exist in Nature, is tantalizing for new Physics. Silicon being the workhorse of electronics industry, this synthesis could have a major impact for novel devices because of the compatibility with existing Si technologies.
[1] P. Vogt , P. De Padova, C. Quaresima, J. Avila, E. Frantzeskakis, M.C. Asensio and G. Le Lay, submitted
[2] G. G. Guzman-Verri and L.C. Lew Yan Voon, Phys. Rev. B 76, 75132 (2007).
[3] M. Houssa, G. Pourtois, M. Heyns, V.V. Afanas'ev, and A. Stesmans,
J. Electrochem. Soc. 158, H107 (2011)[4] P. De Padova et al., Appl. Phys. Lett., 96, 261905 (2010)