title: Single-atom contact mechanics: from atomic scale energy barrier to mechanical relaxation hysteresis.
abstract: The potential energy landscape of surfaces governs the dynamics of adsorbed molecules, as well as atomic scale friction processes. We measure the potential energy landscape of a single-atom tip interacting with a vicinal nonconducting NaCl(100) surface in real space using noncontact atomic force microscopy. We find that the shape of the potential energy profile is of sinusoidal form with a barrier height of 48 meV. Furthermore, we observe a discontinuity in the force curves at specific lattice sites, indicating the onset of reversible yet hysteretic mechanical relaxations.
authors.affiliation: Physikalisches Institut, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Strasse 10, 48149 Münster, Germany. schirmeisen@uni-muenster.de
authors.forename: André
authors.initials: A
authors.lastname: Schirmeisen
authors.forename: Domenique
authors.initials: D
authors.lastname: Weiner
authors.forename: Harald
authors.initials: H
authors.lastname: Fuchs