title: Ultrafast carrier kinetics in exfoliated graphene and thin graphite films.
abstract: Time-resolved transmissivity and reflectivity of exfoliated graphene and thin graphite films on a 295 K SiO(2)/Si substrate are measured at 1300 nm following excitation by 150 fs, 800 nm pump pulses. From the extracted transient optical conductivity we identify a fast recovery time constant which increases from approximately 200 to 300 fs and a longer one which increases from 2.5 to 5 ps as the number of atomic layers increases from 1 to approximately 260. We attribute the temporal recovery to carrier cooling and recombination with the layer dependence related to substrate coupling. Results are compared with related measurements for epitaxial, multilayer graphene.
authors.affiliation: Department of Physics and Institute for Optical Sciences, University of Toronto, Toronto, Canada M5S 1A7. rnewson@physics.utoronto.ca
authors.forename: Ryan W
authors.initials: RW
authors.lastname: Newson
authors.forename: Jesse
authors.initials: J
authors.lastname: Dean
authors.forename: Ben
authors.initials: B
authors.lastname: Schmidt
authors.forename: Henry M
authors.initials: HM
authors.lastname: van Driel
mesh_terms: D003198:Computer Simulation; D006108:Graphite / Q000737:chemistry*; D008027:Light; D008567:Membranes, Artificial; D008956:Models, Chemical; D012031:Refractometry / Q000379:methods*; D012542:Scattering, Radiation
chemical_list: D008567:Membranes, Artificial; D006108:Graphite