Abstract
We present the first fully quantitative and self-consistent analysis of atomic-scale friction, explicitly taking into account the flexibility and low effective mass of the mechanical nanocontact. In a procedure, which is free of the traditional assumptions with respect to the corrugation of the interaction potential of the contact, the basic but experimentally inaccessible system parameter, we arrive at an excellent description of recent nanotribology experiments, including the transition from stick slip to nearly frictionless sliding. We show that, contrary to original interpretation, the ultralow friction observed in some experiments has been largely due to thermal (thermolubricity) rather than mechanistic effects (superlubricity). Furthermore, we observe the manifestations of two different forms of thermally induced sliding dynamics, namely, true thermolubricity (slipperiness based on thermal excitations) and a specific, low-dissipation type of stick-slip motion.
- Received 30 July 2009
DOI:https://doi.org/10.1103/PhysRevB.80.235435
©2009 American Physical Society