The two-dimensional stick-slip phenomenon with atomic resolution

Abstract

The authors investigated the atomic-scale stick-slip motion between muscovite mica and the Si₃N₄ tip apex of a cantilever using an atomic-force microscope combined with a lateral-force microscope (AFM/LFM). As a result, a square-wave behaviour of the cantilever motion was found across the scan direction, in addition to the well known sawtooth behavior along the scan direction. It was also found that the square-wave behavior was synchronized with the sawtooth behavior. To explain these phenomena, the authors proposed the two-dimensional stick-slip model, where the stick-points have the same periodicity as the lattice structure of the mica surface, so that the tip shows a zigzag walk along the scan. This new model seems to explain not only the one-dimensional line-scan profile, but also the contrast mechanism of the two-dimensional image.