title: Intrinsic response time of graphene photodetectors.
abstract: Graphene-based photodetectors are promising new devices for high-speed optoelectronic applications. However, despite recent efforts it is not clear what determines the ultimate speed limit of these devices. Here, we present measurements of the intrinsic response time of metal-graphene-metal photodetectors with monolayer graphene using an optical correlation technique with ultrashort laser pulses. We obtain a response time of 2.1 ps that is mainly given by the short lifetime of the photogenerated carriers. This time translates into a bandwidth of ∼262 GHz. Moreover, we investigate the dependence of the response time on gate voltage and illumination laser power.
authors.affiliation: Institute of Photonics, Vienna University of Technology, Gusshausstrasse 27-29, 1040 Vienna, Austria. alexander.urich@tuwien.ac.at
authors.forename: Alexander
authors.initials: A
authors.lastname: Urich
authors.forename: Karl
authors.initials: K
authors.lastname: Unterrainer
authors.forename: Thomas
authors.initials: T
authors.lastname: Mueller
mesh_terms: D006108:Graphite / Q000737:chemistry*; D008670:Metals / Q000737:chemistry; D036103:Nanotechnology / Q000295:instrumentation*; D010316:Particle Size; D010783:Photometry / Q000295:instrumentation*; D012825:Silicon / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D013499:Surface Properties
chemical_list: D008670:Metals; D012822:Silicon Dioxide; D006108:Graphite; D012825:Silicon