title: Tunneling Desorption of Single Hydrogen on the Surface of Titanium Dioxide.
abstract: We investigated the reaction mechanism of the desorption of single hydrogen from a titanium dioxide surface excited by the tip of a scanning tunneling microscope (STM). Analysis of the desorption yield, in combination with theoretical calculations, indicates the crucial role played by the applied electric field. Instead of facilitating desorption by reducing the barrier height, the applied electric field causes a reduction in the barrier width, which, when coupled with the electron excitation induced by the STM tip, leads to the tunneling desorption of the hydrogen. A significant reduction in the desorption yield was observed when deuterium was used instead of hydrogen, providing further support for the tunneling-desorption mechanism.
authors.affiliation: †International Advanced Research and Education Organization, Tohoku University, Sendai 980-8578, Japan.|‡Surface and Interface Science Laboratory, RIKEN, 2-1 Hirosawa, Saitama 351-0198, Japan.
authors.forename: Taketoshi
authors.initials: T
authors.lastname: Minato
authors.affiliation: §Department of Physics, Chiba University, 1-33 Yayoi, Inage, Chiba 263-0022, Japan.
authors.forename: Seiji
authors.initials: S
authors.lastname: Kajita
authors.affiliation: ∥Department of Chemistry, University College London, London WC1H 0AJ, United Kingdom.
authors.forename: Chi-Lun
authors.initials: CL
authors.lastname: Pang
authors.affiliation: ⊥WPI Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Sendai 980-8577, Japan.
authors.forename: Naoki
authors.initials: N
authors.lastname: Asao
authors.affiliation: ⊥WPI Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Sendai 980-8577, Japan.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Yamamoto
authors.affiliation: §Department of Physics, Chiba University, 1-33 Yayoi, Inage, Chiba 263-0022, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Nakayama
authors.affiliation: #Department of Advanced Materials Science, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan.
authors.forename: Maki
authors.initials: M
authors.lastname: Kawai
authors.affiliation: ‡Surface and Interface Science Laboratory, RIKEN, 2-1 Hirosawa, Saitama 351-0198, Japan.
authors.forename: Yousoo
authors.initials: Y
authors.lastname: Kim
keywords: defect; manipulation; scanning tunneling microscopy; titanium dioxide