AVS 47th International Symposium
    Surface Science Wednesday Sessions
       Session SS-WeP

Paper SS-WeP34
Surface Electronic Structure of Rare Gas Xe on Cu(111): A Scanning Tunneling Microscope Study

Wednesday, October 4, 2000, 11:00 am, Room Exhibit Hall C & D

Session: Poster Session
Presenter: J.-Y. Park, Seoul National University, Korea
Authors: J.-Y. Park, Seoul National University, Korea
U.D. Ham, Seoul National University, Korea
S.-J. Kahng, University of Illinois at Urbana- Champaign
Y. Kuk, Seoul National University, Korea
Correspondent: Click to Email
A newly built ultrahigh vacuum cryogenic scanning tunneling microscope (STM) was used to study the modified surface state and image state on an adsorbate-covered surface, one monolayer (ML) Xe on Cu(111). Electron standing waves were observed on 1 ML Xe-covered Cu(111) as well as on bare Cu surface. By carefully controlling the Xe coverage, standing waves on both bare Cu surface and 1 ML Xe-covered Cu surface could be observed simultaneously in one STM image. Therefore, any possibility of artifact due to different conditions of the tunneling tip can be ruled out. The wavelength of standing waves on Xe layer is ~15% longer (~17Å) than that on Cu surface at sample bias as low as 10meV. By performing scanning tunneling spectroscopy on this surface, dispersions of the surface state both on Xe layer and bare Cu surface are determined. It was found that the onset of the surface state is shifted towards Fermi level by (130±20) meV and the effective electron mass is slightly larger on Xe layer than on bare Cu surface. The electronic lifetime, the multilayer effect, and the effect of image states will also be discussed.