title: Nanoscale imaging of electronic surface transport probed by atom movements induced by scanning tunneling microscope current.
abstract: The hopping movements of Cl atoms on a Si(111)-(7 x 7) surface that are enhanced by an electron injection from tips of a scanning tunneling microscope (STM) exhibit a spatial spread from the electron injection point with an anisotropic distribution. The enhanced hopping effect becomes greatest at a sample bias voltage being resonant with the Si-Cl antibonding states and also exhibits an oscillatory decay with the distance from the injection point characterized by the wavelength depending on the bias voltage. All of these facts can be interpreted in terms of the coherent expansion of the electron wave packets locally formed at the STM tip.
authors.affiliation: Department of Applied Physics, Graduate School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-6856, Japan.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Mera
authors.forename: Koji
authors.initials: K
authors.lastname: Maeda