Holographic images of iodine atoms on a silver surface from electron emission patterns

Abstract

BARTON1 has suggested that photoelectron interference patterns may be used directly as holograms to obtain atomic-resolution images of surface structures. Bulk structures have been obtained previously by this means from experimental patterns of high-energy Kikuchi (quasi-elastically scattered) and Auger electrons2,3. Here we test the feasibility of this technique for determination of surface structures using Auger intensity patterns obtained4,5 from iodine chemisorbed on a pseudomorphic silver monolayer on Pt{111}. By direct numerical holographic inversion, we obtain three-dimensional images which show that iodine adatoms are located in hollows of 3-fold symmetry on the surface. The images yield the site symmetry with good atomic resolution in the surface plane, but suffer from poor resolution along the Ag–I axis. We anticipate that data with better angular resolution obtained at low temperatures would improve the spatial resolution of such images.