Temperature-Dependent Far-Infrared Response Of Epitaxial Multilayer Graphene

The optical response of pristine and FeCl3-intercalated epitaxial graphene has been studied over the temperature range from 11K to 296 K. The far-infrared (FIR) Drude conductivity of pristine graphene rises with increasing temperature, opposite to the behavior of intercalated graphene. This is a result of intercalation-induced p-type doping compensating the intrinsic n-doping in epitaxial graphene. Temperature-dependent Drude parameters are obtained by fitting the FIR response. This study demonstrates the influence of temperature variation on the optical properties of graphene, which should be a vital factor to be considered for graphene-based device applications. (C) 2013 AIP Publishing LLC.