Title: Silicene, graphene’s topologically non-trivial cousin

Speaker: Guy LE LAY Aix-Marseille University, France & Consiglio Nationale delle Ricerce-ISM, Italy

Location: Room 111, Physics Building

Time: 3:00pm, 26-09-2012, Wednesday

Abstract:

We have shown recently compelling evidences for the first synthesis of epitaxial silicene sheets hosting massless relativistic Dirac fermions with a Fermi velocity exceeding that of free standing graphene [1]. Silicene, which does not exist in nature, is the all silicon based analogue of graphene. This discovery has followed that of a one-dimensional grating of massively parallel silicene nanoribbons with a magic width of just 1.6 nm [2]. Silicene is predicted to have non-trivial topological properties. Hence, it could offer the possibility, if interfaced with a s-wave superconductor, for advances in the long quest for Majorana fermions.

Here, we will review the genesis of this discovery, describe the present state of the art and draw perspectives for other two-dimensional nano-lattices and future applications.

* guy.lelay@univ-provence.fr

[1] P. Vogt et al., Phys. Rev. Lett., 108, 155501 (2012) 155501 and Nature 485, 9 (2012).

[2] P. De Padova et al., Appl. Phys. Lett., 96, 261905 (2010).

Biology:

Prof. Guy Le Lay is Full Professor of Physics since 1981. He has reached the topmost level attainable in France in 2007 (Classe exceptionnelle 2). He has been for several years a member of the Comité National des Universités and was for five years President of the regional section of the French Physical Society. Prof. Le Lay is a recognized specialist of Nanoscience, as well as an expert in Synchrotron Radiation. During his career, he has chaired and organized a number of international Schools, Workshops and Conferences (one about each second year in the last 20 years) and served in many UNESCO, NATO, EC, international, national and regional panels and expert committees. Prof. Le Lay is also involved in some art-science collaborative projects that have been performed and exhibited, especially during the Einstein International Year of Physics, in 2005. Prof. Le Lay’s main research focuses in recent years were on the study of two-dimensional silicon/germanium adlayers on silver/gold single crystal surfaces, which has led to the discovery of silicene, the all silicon based graphene analogue, and, on the other hand, on the study by femto second X-ray Free Electron Lasers of the anomalous dynamics of strongly correlated prototypical systems, e.g., tin/lead adatoms adsorbed at the silicon or germanium (111) surfaces. His Hirsch h-index: 33 (according to ISI Web of Knowledge, that gives, as of August 2012, 218 publications 4,116 total citations and 18.88 average citations per item). Prof. Guy Le Lay has been a nominator for the Nobel Prize, the Japan Prize and the Kyoto Prize.