title: Molecular-scale quantum dots from carbon nanotube heterojunctions.
abstract: Carbon nanotube heterojunctions (HJs), which seamlessly connect nanotubes of different chiral structure using a small number of atomic-scale defects, represent the ultimate scaling of electronic interfaces. Here we report the first electrical transport measurements on a HJ formed between semiconducting and metallic nanotubes of known chiralities. These measurements reveal asymmetric IV-characteristics and the presence of a quantum dot (QD) with approximately 60 meV charging energy and approximately 75 meV level spacing. A detailed atomistic and electronic model of the HJ enables the identification of specific defect arrangements that lead to the QD behavior consistent with the experiment.
authors.affiliation: Department of Mechanical Engineering, Center for Electronic Transport in Molecular Nanostructures, Columbia University, New York, New York 10027, USA.
authors.forename: Bhupesh
authors.initials: B
authors.lastname: Chandra
authors.forename: Joydeep
authors.initials: J
authors.lastname: Bhattacharjee
authors.forename: Meninder
authors.initials: M
authors.lastname: Purewal
authors.forename: Young-Woo
authors.initials: YW
authors.lastname: Son
authors.forename: Yang
authors.initials: Y
authors.lastname: Wu
authors.forename: Mingyuan
authors.initials: M
authors.lastname: Huang
authors.forename: Hugen
authors.initials: H
authors.lastname: Yan
authors.forename: Tony F
authors.initials: TF
authors.lastname: Heinz
authors.forename: Philip
authors.initials: P
authors.lastname: Kim
authors.forename: Jeffrey B
authors.initials: JB
authors.lastname: Neaton
authors.forename: James
authors.initials: J
authors.lastname: Hone