Friction on incommensurate substrates: Role of anharmonicity and defects
arXiv:2009.14562 · doi:10.1103/PhysRevE.104.014802
Abstract
We present Molecular Dynamics simulations of one- and two-dimensional bead-spring models sliding on incommensurate substrates. We investigate how sliding friction is affected by interaction anharmonicity and structural defects. In their absence, we confirm earlier findings, namely, that at special resonance sliding velocities, friction is maximal. When sliding off-resonance, partially thermalized states are possible, whereby only a small number of vibrational modes becomes excited, but whose kinetic energies are already Maxwell-Boltzmann distributed. Anharmonicity and defects typically destroy partial thermalization, and instead lead to full thermalization, implying much higher friction. For sliders with periodic boundaries, thermalization begins with vibrational modes whose spatial modulation is compatible with the incommensurate lattice. For a disc-shaped slider, modes corresponding to modulations compatible with the slider radius are initially the most dominant. By tuning the mechanical properties of the slider's edge, this effect can be controlled, resulting in significant changes in the sliding distance covered.
arXiv comment10 pages, 9 Figures
References in corpus (15)
- Tuning friction atom-by-atom in an ion-crystal simulator
- Observation of Aubry transition in finite atom chains via friction
- Static friction scaling of physisorbed islands: the key is in the edge
- Low friction and rotational dynamics of crystalline flakes in solid lubrication
- Experimental observation of the Aubry transition in two-dimensional colloidal monolayers
- Magnetic friction in Ising spin systems
- Parameter-free dissipation in simulated sliding friction
- Onset of sliding friction in incommensurate systems
- A simple model for the vibrational modes in honeycomb lattices
- Nanoscopic friction under electrochemical control
- Emergent friction in two-dimensional Frenkel-Kontorova models
- Optimal Energy Dissipation in Sliding Friction Simulations
- On the connection between sliding friction and phonon lifetimes: Thermostat induced thermolubricity effects in molecular dynamics simulations
- Effect of temperature and velocity on superlubricity
- Breakdown of a conservation law in incommensurate systems