title: Graphene based quantum dots.
abstract: Laterally localized electronic states are identified on a single layer of graphene on ruthenium by low temperature scanning tunneling spectroscopy (STS). The individual states are separated by 3 nm and comprise regions of about 90 carbon atoms. This constitutes a highly regular quantum dot-array with molecular precision. It is evidenced by quantum well resonances (QWRs) with energies that relate to the corrugation of the graphene layer. The dI/dV conductance spectra are modeled by a layer height dependent potential-well with a delta-function potential that describes the barrier for electron penetration into graphene. The resulting QWRs are strongest and lowest in energy on the isolated 'hill' regions with a diameter of 2 nm, where the graphene is decoupled from the surface.
authors.affiliation: Institute of Physics, Chinese Academy of Sciences, Beijing, People's Republic of China.
authors.forename: H G
authors.initials: HG
authors.lastname: Zhang
authors.forename: H
authors.initials: H
authors.lastname: Hu
authors.forename: Y
authors.initials: Y
authors.lastname: Pan
authors.forename: J H
authors.initials: JH
authors.lastname: Mao
authors.forename: M
authors.initials: M
authors.lastname: Gao
authors.forename: H M
authors.initials: HM
authors.lastname: Guo
authors.forename: S X
authors.initials: SX
authors.lastname: Du
authors.forename: T
authors.initials: T
authors.lastname: Greber
authors.forename: H-J
authors.initials: HJ
authors.lastname: Gao