Calculation of an Atomically Modulated Friction Force in Atomic-Force Microscopy

Abstract

We investigate the microscopic mechanism of energy dissipation in the friction force microscope (FFM), which is a modification of the atomic-force microscope for application to friction. Based on ab initio results for the interaction between Pd and graphite, we determine the atomic-scale modulation of the friction force and the corresponding stick-slip motion at the interface during the relative motion between these solids. We propose two idealized versions of the FFM and show that the friction force depends not only on the Pd-graphite interaction potential, but even more critically on the construction parameters of such a microscope.