title: Photo-thermoelectric effect at a graphene interface junction.
abstract: We investigate the optoelectronic response of a graphene single-bilayer interface junction using photocurrent (PC) microscopy. We measure the polarity and amplitude of the PC while varying the Fermi level by tuning a gate voltage. These measurements show that the generation of PC is by a photothermoelectric effect. The PC displays a factor of approximately 10 increase at the cryogenic temperature as compared to room temperature. Assuming the thermoelectric power has a linear dependence on the temperature, the inferred graphene thermal conductivity from temperature dependent measurements has a T(1.5) dependence below approximately 100 K, which agrees with recent theoretical predictions.
authors.affiliation: Center For Nanoscale Systems, Cornell University,Ithaca, New York 14853, USA.
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Xu
authors.forename: Nathaniel M
authors.initials: NM
authors.lastname: Gabor
authors.forename: Jonathan S
authors.initials: JS
authors.lastname: Alden
authors.forename: Arend M
authors.initials: AM
authors.lastname: van der Zande
authors.forename: Paul L
authors.initials: PL
authors.lastname: McEuen