Scanning-tunneling spectroscopy of surface-state electrons scattered by a slightly disordered two-dimensional dilute "solid": Ce on Ag(111).
Low temperature (3.9 K) scanning-tunneling spectroscopy on a hexagonal superlattice of Ce adatoms on Ag(111) reveals site-dependent characteristic features in differential conductance spectra and in spectroscopic images at atomic-scale spatial resolution. Using a tight-binding model, we relate the overall spectral structures to the scattering of Ag(111) surface-state electrons by the Ce adatoms, the site dependence to the disorder induced by imperfections of the superlattice, and the opening of a gap in the local density of states to the observed stabilization of superlattices with adatom distances in the range of 2.3-3.5 nm.
Ternes
Markus
M
Institut de Physique des Nanostructures, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland. Markus.Ternes@epfl.ch
Weber
Cédric
C
Pivetta
Marina
M
Patthey
François
F
Pelz
Jonathan P
JP
Giamarchi
Thierry
T
Mila
Frédéric
F
Schneider
Wolf-Dieter
WD