By Prof. Hamid Oughaddou, Institut des Sciences Moléculaires d’Orsay, Université Paris-Sud, France
The remarkable properties of graphene stem from its two-dimensional structure, with a linear dispersion of the electronic states at the corners of the Brillouin zone (BZ) forming a Dirac cone. Since then, other 2D materials have been emerged based on boron, silicon, germanium, phosphorus, tin, and metal di-chalcogenides. Indeed, even though graphene has a very high potential, its metallic character and the absence of a band gap are significant limitations for a large variety of devices.
Silicene is considered to be promising materials. Theoretical studies have shown that its structure shows similar electronic properties that graphene; such as a Dirac cone at the high symmetry point of the Brillion zone, large charge carrier mobility and Hall effect.
Phosphorene has both an intrinsic tunable direct band gap and high carrier mobility values, which make it suitable for a large variety of optical and electronic devices. However, the synthesis of single-layer phosphorene is a major challenge because the principal process currently used to produce phosphorene is exfoliation.
In my talk, I will present an experimental investigation of silicene and phosphorene using low energy electron diffraction (LEED), high resolution angle-resolved photoemission spectroscopy (HR-ARPES), and scanning tunneling microscopy (STM).
Dr. Hamid Oughaddou is full-professor at the University of Cergy-Pontoise. He is actually leader of New 2D material group at the ISMO (Institut des Sciences Moléculaires d’Orsay) at the University of Paris Sud. He works, particularly, on semiconductor nanostructures on metallic surfaces. Prof. H. Oughaddou has pioneered the silicene studies by demonstrating for the first time the growth of silicene on metallic substrates. He is actually working also on synthesis of phosphorene by Molecular beam epitaxy.