title: Fabrication of coupled graphene-nanotube quantum devices.
abstract: We report on the fabrication and characterization of all-carbon hybrid  quantum devices based on graphene and single-walled carbon nanotubes. We discuss both carbon nanotube quantum dot devices with graphene charge detectors and nanotube quantum dots with graphene leads. The devices are fabricated by chemical vapor deposition growth of carbon nanotubes and subsequent structuring of mechanically exfoliated graphene. We study the detection of individual charging events in the carbon nanotube quantum dot by a nearby graphene nanoribbon and show that they lead to changes of up to 20% of the conductance maxima in the graphene nanoribbon, acting as a well performing charge detector. Moreover, we discuss an electrically coupled graphene-nanotube junction, which exhibits a tunneling barrier with tunneling rates in the low GHz regime. This allows us to observe Coulomb blockade on a carbon nanotube quantum dot with graphene source and drain leads.
authors.affiliation: II Institute of Physics B, RWTH Aachen University, D-52074 Aachen, EU, Germany. stephan.engels@rwth-aachen.de
authors.forename: S
authors.initials: S
authors.lastname: Engels
authors.forename: P
authors.initials: P
authors.lastname: Weber
authors.forename: B
authors.initials: B
authors.lastname: Terrés
authors.forename: J
authors.initials: J
authors.lastname: Dauber
authors.forename: C
authors.initials: C
authors.lastname: Meyer
authors.forename: C
authors.initials: C
authors.lastname: Volk
authors.forename: S
authors.initials: S
authors.lastname: Trellenkamp
authors.forename: U
authors.initials: U
authors.lastname: Wichmann
authors.forename: C
authors.initials: C
authors.lastname: Stampfer