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arXiv · 0810.0165

Friction at Atomic-Scale Surface Steps: Experiment and Theory

Hendrik Holscher·Daniel Ebeling·Udo D. Schwarz
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Abstract

Experiments performed by friction force microscopy at atomic-scale surface steps on graphite, MoS$_2$, and NaCl in ambient conditions are presented. Both step-down and step-up scans exhibit higher frictional forces at the edge, but distinguish in their load dependence: While the additional frictional force due to the step edge increases linearly with load if the tip has to jump a step up, it remains constant for downward jumps. This phenomena represents a universal effect that can be explained in terms of a modified Prandtl-Tomlinson model featuring a Schoebel-Ehrlich barrier at steps.

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Hendrik Holscher, Daniel Ebeling, Udo D. Schwarz. 2008-10-01. Friction at Atomic-Scale Surface Steps: Experiment and Theory. https://arxiv.org/abs/0810.0165

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