title: Single molecular resistive switch obtained via sliding multiple anchoring points and varying effective wire length.
abstract: A single molecular resistive (conductance) switch via control of anchoring positions was examined by using a molecule consisting of more than two same anchors. For this purpose, we adopted the covered quaterthiophene (QT)-based molecular wire junction. The QT-based wire consisted of two thiophene ring anchors on each side; thus, shift of anchors was potentially possible without a change in the binding modes and distortion of the intramolecular structure. We observed three distinct conductance states by using scanning tunneling microscope-based break junction technique. A detailed analysis of the experimental data and first-principles calculations revealed that the mechanism of the resistive switch could be explained by standard length dependence (exponential decay) of conductance. Here, the length is the distance between the anchoring points, i.e., length of the bridged π-conjugated backbone. Most importantly, this effective tunneling length was variable via only controlling the anchoring positions in the same molecule. Furthermore, we experimentally showed the possibility of a dynamic switch of anchoring positions by mechanical control. The results suggested a distinct strategy to design functional devices via contact engineering.
authors.affiliation: Department of Chemistry, Graduate School of Science and Engineering, Tokyo Institute of Technology , 2-12-1 W4-10, Ookayama, Meguro-ku, Tokyo 152-8551, Japan.
authors.forename: Manabu
authors.initials: M
authors.lastname: Kiguchi
authors.forename: Tatsuhiko
authors.initials: T
authors.lastname: Ohto
authors.forename: Shintaro
authors.initials: S
authors.lastname: Fujii
authors.forename: Kazunori
authors.initials: K
authors.lastname: Sugiyasu
authors.forename: Shigeto
authors.initials: S
authors.lastname: Nakajima
authors.forename: Masayuki
authors.initials: M
authors.lastname: Takeuchi
authors.forename: Hisao
authors.initials: H
authors.lastname: Nakamura