Effects of surface disorder and temperature on atomic friction

Abstract

We have investigated the effect of surface disorder on atomic friction in the stick-slip dynamical regime of a one-dimensional Prandtl-Tomlinson model. We find that disorder in the substrate potential can modify the mean slip length and then it changes the friction force of the system. In particular, the effect of the disorder is more important at low temperatures and close to dynamical transition points or at high loads. We show results for different values of temperature, amplitude of the corrugation potential, dragging velocity, and damping. Special care is put in the comparison between the results of the regular and the disordered cases at many different temperatures and in the understanding of the combined effect of disorder and temperature in the dynamics of the system. To finish, we present some results on the robustness of the results against a change in the effective damping of the system.

Out-of-plane and in-plane actuation effects on atomic-scale friction

“…In order to analyze ac-actuation effects on atomic-scale friction, we start from the one-dimensional Prandtl-Tomlinson (PT) model including thermal effects [19][20][21][22][23][24][25][26]:…”

Stick–Slip and the Transition to Steady Sliding in a 2D Granular Medium and a Fixed Particle Lattice

“…At the atomic scale, inter-particle interactions are well defined, and a variety of models have been suggested to describe how static friction and stickslip phenomena at a sliding interface arise from the molecular nature of the materials at the interface, and how energy is dissipated through the excitation of molecular and electronic excitations (ROBBINS and KRIM 1998;FILIPPOV et al 2004). Length scales here are of the order of a few Angstroms, and the relevant systems are highly sensitive to both temperature (BAREL and URBAKH 2010;JANSEN et al 2010) and sliding velocity levels (LUAN and ROBBINS 2004).…”

Stochastic Modeling and Rate Theory of Atomic Friction

“…However, in general, the situation can be more complex and in some cases a temperature-induced enhancement of nanoscale friction was predicted [46,48,61] due to the effect of temperature on the slip length. Friction reduction is more significant at low velocities and moderate damping values.…”

“…For instance, the standard PT model is characterized by a sinusoidal tip-substrate interaction potential (15) and corresponds to a perfectly periodic substrate lattice. However, other cases are worth to be analyzed, such as quasiperiodic lattices [46,47] and lattices including defects [48,61].…”

“…Note that, although a single-harmonic potential (15) is the one that is used most often in modeling, other possibilities have also been considered in the literature, e.g. a potential with sharp minima and flat maxima [45], quasiperiodic potentials [46,47], potentials with localized Gaussian perturbations [48], fractal potentials [49], etc.…”