title: Manifestation of work function difference in high order Gundlach oscillation.
abstract: Gundlach oscillation (or the standing-wave state) is a general phenomenon manifesting in the tunneling spectrum acquired from a metal surface using scanning tunneling spectroscopy. Previous studies relate the energy shift between peaks of the lowest-order Gundlach oscillation observed on the thin film and the metal substrate to the difference in their work functions. By observing Gundlach oscillations on Ag/Au(111), Ag/Cu(111), and Co/Cu(111) systems, we demonstrate that the work function difference is not the energy shift of the lowest order but the ones of higher order where a constant energy shift exhibits. Higher order Gundlach oscillations can thus be applied to determine the work function of thin metal films precisely.
authors.affiliation: Institute of Physics, Academia Sinica, Nankang, Taipei, Taiwan, Republic of China.
authors.forename: C L
authors.initials: CL
authors.lastname: Lin
authors.forename: S M
authors.initials: SM
authors.lastname: Lu
authors.forename: W B
authors.initials: WB
authors.lastname: Su
authors.forename: H T
authors.initials: HT
authors.lastname: Shih
authors.forename: B F
authors.initials: BF
authors.lastname: Wu
authors.forename: Y D
authors.initials: YD
authors.lastname: Yao
authors.forename: C S
authors.initials: CS
authors.lastname: Chang
authors.forename: Tien T
authors.initials: TT
authors.lastname: Tsong