Interaction effects in graphene: Where are they?

Who:  Daniel Sheehy - (Louisiana State University)
Where:  Smith Seminar Room (1080 PRB)
When:  Monday, November 2, 2009 at 11:30
Type:  Condensed Matter Theory Seminar

Description: Graphene, a one-atom thick sheet of graphite, has received a large amount of attention following its experimental isolation in 2005. At low energies, graphene possesses an emergent relativistic symmetry, and can be described in terms of linearly-dispersing massless "Dirac"fermions, with a velocity that is determined by band structure and experimentally measured to be 300 times smaller than the speed of light. This approximate relativistic behavior is, naively, broken by the presence of the unscreened long-range Coulomb interaction, although many experiments can be explained in terms of a non-interacting picture. I will discuss how the Coulomb interaction will be manifested in various experimentally observable quantities, including the heat capacity, diamagnetic response, and optical conductivity.