Abstracts2014‎ > ‎

Justin Wells: Graphene's overlooked sigma band

posted 4 Jun 2014, 02:26 by Mette Lund Meisner
Justin Wells, Department of Physics, Norwegian University of Science and Technology (NTNU), Trondheim Norway. justin.wells@ntnu.no

Graphene's linearly dispersing pi-band is the centre of much attention and a wide range of novel applications have been speculated. In stark contrast, the wide gap sigma band remains almost entirely unexplored - presumably because it lies several eV form the Fermi level, has little influence on the charge transport properties. 
In fact, the sigma-band is interesting for several reasons; not least, that it supports a strong electron-phonon-coupling `kink'. In the traditional view, this should be impossible, since such behaviour has only previously been observed close to the Fermi level. We show that the sharp change in the density of occupied states at the sigma band maximum is responsible.   
In this talk, I will discuss how many-body interactions, such as electron-phonon coupling, can be observed using a combination of photoemission and simulations. In particular, I will relate this to graphene's sigma band and speculate on the possibility of a superconducting phase.

Justin is currently Associate Professor at the Norwegian University of Science and Technology (NTNU) in Trondheim. Justin has a broad range of research interests, relating to charge confinement and spin and charge transport in reduced dimensions. He received his Ph.D. from Aarhus University in 2006, and has since held PostDoctoral positions in Aarhus, Trondheim and Lund. He was appointed as Associate Professor at NTNU, Department of Physics, in autumn 2012.