title: Pulsed Near-IR Photoresponse in a Bi-metal Contacted Graphene Photodetector.
abstract: We use an ultra-fast near-infrared pulse coincidence technique to study the time, temperature, and power dependence of the photoresponse of a bi-metal contacted graphene photodetector. We observe two components of the photovoltage signal. One component is gate-voltage dependent, linear in power at room temperature and sub-linear at low temperature-consistent with the hot-electron photothermoelectric effect due to absorption in the graphene. The power dependence is consistent with supercollision-dominated cooling in graphene. The other component is gate-voltage independent and linear in temperature and power, which we interpret as due to thermoelectricity of the metal electrodes due to differential light absorption.
authors.affiliation: Center for Nanophysics and Advanced Materials, University of Maryland, College Park, MD 20742-4111 USA.
authors.forename: Xinghan
authors.initials: X
authors.lastname: Cai
authors.affiliation: Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, MD 20742 USA.
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Suess
authors.affiliation: Center for Nanophysics and Advanced Materials, University of Maryland, College Park, MD 20742-4111 USA.
authors.forename: H Dennis
authors.initials: HD
authors.lastname: Drew
authors.affiliation: Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, MD 20742 USA.
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Murphy
authors.affiliation: Department of Physics, University of Massachusetts, Amherst, MA 01003, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Yan
authors.affiliation: Center for Nanophysics and Advanced Materials, University of Maryland, College Park, MD 20742-4111 USA.|School of Physics, Monash University, 3800 Victoria, Australia.
authors.forename: Michael S
authors.initials: MS
authors.lastname: Fuhrer