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arXiv · 0709.3706

Static friction on the fly: velocity depinning transitions of lubricants in motion

A. Vanossi·N. Manini·F. Caruso·G. E. Santoro·E. Tosatti
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Abstract

The dragging velocity of a model solid lubricant confined between sliding periodic substrates exhibits a phase transition between two regimes, respectively with quantized and with continuous lubricant center-of-mass velocity. The transition, occurring for increasing external driving force F_ext acting on the lubricant, displays a large hysteresis, and has the features of depinning transitions in static friction, only taking place on the fly. Although different in nature, this phenomenon appears isomorphic to a static Aubry depinning transition in a Frenkel-Kontorova model, the role of particles now taken by the moving kinks of the lubricant-substrate interface. We suggest a possible realization in 2D optical lattice experiments.

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A. Vanossi, N. Manini, F. Caruso, G. E. Santoro, E. Tosatti. 2007-09-27. Static friction on the fly: velocity depinning transitions of lubricants in motion. https://doi.org/10.1103/physrevlett.99.206101

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