Analytic understanding and control of dynamical friction

TL;DR

This paper uses linear-response theory to analytically explain non-monotonic behaviors in phononic friction as a function of sliding speed, matching simulations and enabling control of frictional properties.

Contribution

It provides an analytical framework predicting frictional singularities and the speed dependence of friction, enhancing understanding and control of phononic friction.

Findings

Analytical formula accurately reproduces atomistic simulation results.

Identifies frictional singularities related to phonon interactions.

Offers a method to tailor frictional behavior by modifying interactions.

Abstract

Recent model simulations discovered unexpected non-monotonic features in the wear-free dry phononic friction as a function of the sliding speed. Here we demonstrate that a rather straight- forward application of linear-response theory, appropriate in a regime of weak slider-substrate in- teraction, predicts frictional one-phonon singularities which imply a non-trivial dependence of the dynamical friction force on the slider speed and/or coupling to the substrate. The explicit formula which we derive reproduces very accurately the classical atomistic simulations when available. By modifying the slider-substrate interaction the analytical understanding obtained provides a practical means to tailor and control the speed dependence of friction with substantial freedom.