Graphene, a material first synthesized controllably in 2004, consists of an atomic monolayer of carbon atoms arranged in a honeycomb lattice. Its discovery (made possible thanks to a process known as “exfoliation”), and the later characterization of its electronic properties, paved the way for a new and vibrant field in Condensed Matter Physics, with both fundamental and applied implications. Electron mobility in graphene is higher than in any metal, and electrons do not localize due to disorder or imperfections. In addition, graphene is transparent, flexible, extremely resistant, extremely light and a good heat conductor. All these features make graphene an excellent multi-functional material with a broad variety of potential applications.
The Condensed Matter Theory Group at IFIR works on the structural properties of graphene, its corrugation and the implications on the mobility of electrons. We have focused recently on the vibrations of the carbon honeycomb lattice, and its consequences for its thermal conductivity. We are at present studying graphene nanoribbons in different situations. We are particularly interested in the relative contribution of in-plane vibrations as compared to the out-of-plane vibrations (i.e., the so-called “flexural modes”). In addition, we have studied the effect of different perturbations, such as the presence of vacancies (isolated or in clusters), isotope effects, and boundary conditions of graphene nanoribbons. In our last work (see picture) we have studied different mechanisms to control the relative contribution of the aforementioned vibration modes to the thermal conductivity.
“Role of atomic vacancies and boundary conditions on ballistic thermal transport in graphene nanoribbons”
P. Scuracchio, S. Costamagna, F. M. Peeters y A. Dobry
PHYSICALREVIEW B 90, 035429 (2014)