title: First-principles study on electron transport of carbon dumbbells C60-C(n)-C60.
abstract: Electronic transport properties of carbon dumbbells, a new type of carbon hybrid nanostructures formed by connecting carbon atomic chains to two fullerenes C(60), are investigated by using nonequilibrium Green's functions in combination with the density-functional theory. Specifically, the transport properties as a function of the carbon chain length n are examined. An obvious metal-insulator-like oscillation has been achieved with the increase of the carbon chain length. When n is even, the device behaves as a metal. In contrast, when n is odd, it behaves as an insulator. It is quite different to the carbon chains directly sandwiched between metallic leads where the low conductance states are observed for even n while the high conductance states are observed for odd n. Such a difference arises from the screening effect of C(60)s.
authors.affiliation: Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, China.
authors.forename: R N
authors.initials: RN
authors.lastname: Wang
authors.forename: X H
authors.initials: XH
authors.lastname: Zheng
authors.forename: L L
authors.initials: LL
authors.lastname: Song
authors.forename: Z
authors.initials: Z
authors.lastname: Zeng