title: Quantum Transport in Gated Dangling-Bond Atomic Wires.
abstract: A single line of dangling bonds (DBs) on Si(100)-2 × 1:H surface forms a perfect metallic atomic-wire. In this work, we investigate quantum transport properties of such dangling bond wires (DBWs) by a state-of-the-art first-principles technique. It is found that the conductance of the DBW can be gated by electrostatic potential and orbital overlap due to only a single DB center (DBC) within a distance of ∼16 Å from the DBW. The gating effect is more pronounced for two DBCs and especially, when these two DB "gates" are within ∼3.9 Å from each other. These effective length scales are in excellent agreement with those measured in scanning tunnelling microscope experiments. By analyzing transmission spectrum and density of states of DBC-DBW systems, with or without subsurface doping, for different length of the DBW, distance between DBCs and the DBW, and distance between DB gates, we conclude that charge transport in a DBW can be regulated to have both an on-state and an off-state using only one or two DBs.
authors.affiliation: Center for the Physics of Materials and Department of Physics, McGill University , Montreal, Quebec H3A 2T8, Canada.
authors.forename: S
authors.identifier: 0000-0002-8071-3216
authors.initials: S
authors.lastname: Bohloul
authors.affiliation: Center for the Physics of Materials and Department of Physics, McGill University , Montreal, Quebec H3A 2T8, Canada.
authors.forename: Q
authors.initials: Q
authors.lastname: Shi
authors.affiliation: National Institute for Nanotechnology, National Research Council of Canada , Edmonton, Alberta T6G 2M9, Canada.|Department of Physics, University of Alberta , Edmonton, Alberta T6G 2E1, Canada.
authors.forename: Robert A
authors.initials: RA
authors.lastname: Wolkow
authors.affiliation: Center for the Physics of Materials and Department of Physics, McGill University , Montreal, Quebec H3A 2T8, Canada.
authors.forename: Hong
authors.initials: H
authors.lastname: Guo
keywords: Dangling bond nanowires; atomic scale switch; interconnects; quantum transport