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arXiv · 0804.1519

Role of transverse displacements for a quantized-velocity state of the lubricant

Ivano Eligio Castelli·Nicola Manini·Rosario Capozza·Andrea Vanossi·Giuseppe E. Santoro·Erio Tosatti
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Abstract

Within the idealized scheme of a 1-dimensional Frenkel-Kontorova-like model, a special "quantized" sliding state was found for a solid lubricant confined between two periodic layers [PRL 97, 056101 (2006)]. This state, characterized by a nontrivial geometrically fixed ratio of the mean lubricant drift velocity and the externally imposed translational velocity v_ext, was understood as due to the kinks (or solitons), formed by the lubricant due to incommensuracy with one of the substrates, pinning to the other sliding substrate. A quantized sliding state of the same nature is demonstrated here for a substantially less idealized 2-dimensional model, where atoms are allowed to move perpendicularly to the sliding direction and interact via Lennard-Jones potentials. Clear evidence for quantized sliding at finite temperature is provided, even with a confined solid lubricant composed of multiple (up to 6) lubricant layers. Characteristic backward lubricant motion produced by the presence of "anti-kinks" is also shown in this more realistic context.

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Ivano Eligio Castelli, Nicola Manini, Rosario Capozza, Andrea Vanossi, Giuseppe E. Santoro, Erio Tosatti. 2008-04-09. Role of transverse displacements for a quantized-velocity state of the lubricant. https://doi.org/10.1088/0953-8984%2F20%2F35%2F354005

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