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HL: Fachverband Halbleiterphysik

HL 41: Transport: Graphene (organized by TT)

HL 41.6: Vortrag

Dienstag, 1. April 2014, 11:15–11:30, WIL C107

Optical conductivity of graphene — •Julia Link, Peter P. Orth, and Jörg Schmalian — Institute for Theory of Condensed Matter, Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany

Graphene is a two-dimensional crystal of carbon atoms with a honeycomb structure, which has many fascinating optical and electronical properties. It has a high mobility of electrons at room temperature and a high transparency of light with 97.7%. In the optical domain, the value of the transparency does not depend on the frequency of white light being transmitted and is thus universal. This universality is linked to the fine structure constant α=1/137 and can be derived using non-interacting Dirac fermions.

We aim to understand the correction of the optical transparency due to Coulomb interaction. Since there is a long dispute about this correction in the literature [1-6], we try to resolve this controversy. Therefore we combine two different regularization schemes: dimensional regularization and a deformation of the Coulomb potential. We discuss the physical implication of the choice of the regularization.
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