Quantum size effects in adatom island decay.
The decay of hexagonal Ag adatom islands on top of larger Ag adatom islands on a Ag(111) surface is followed by a fast-scanning tunneling microscope. Islands do not always show the expected increase in decay rate with decreasing island size. Rather, distinct quantum size effects are observed where the decay rate decreases significantly for islands with diameters of 6, 9.3, 12.6, and 15.6 nm. We show that electron confinement of the surface state electrons is responsible for this enhancement of the detachment barrier for adatoms from the island edge.
Morgenstern
Karina
K
Institut für Festkörperphysik, Universität Hannover, Appelstrasse 2, D-30167 Hannover, Germany.
Laegsgaard
Erik
E
Besenbacher
Flemming
F