Atomic motion at germanium surfaces: Scanning tunneling microscopy and Monte Carlo simulations

The observation of the motion of an adatom on the reconstructed Ge (111) is a rare event, which will be examined by way of simple adatom-surface interaction models. Estimations of the residence time of adatoms on energetically favorable sites indicate that a thermal excitation can account for casual adatom motion and that a strong tip-surface interaction is not obviously needed to explain the changes found in sequences of scanning tunneling microscopy (STM) images of the same surface areas. (C) 1998 John Wiley & Sons, Inc.