Authors: A. Fasolino, L. Consoli and H.J.F. Knops
Affilation: Research Institute for Materials, Institute of Theoretical Physics, University of Nijmegen, LN
Pages: 95 - 95
Keywords: atomistic friction, phonons, incommensurate systems
We study the mechanisms for dissipation of mechanical energy during the sliding of two bodies against each other, namely the origin of friction at an atomic scale. We consider the most likely case of incommensurate contacting lattices. For this purpose, we study the dynamics of an infinite incommensurate chain onto a periodic lattice, modeled by the Frenkel Kontorova Hamiltonian with initial kinetic energy. By means of numerical and analytical results we have shown that transfer of translational energy from the center of mass to internal vibrations (heat) occurs via a novel kind of dissipative parametric resonances involving several resonant phonons. We review these results focusing on the computational aspects related to incommensurate structures. Here we show that the above mechanism leads to thermal equilibrium via a dynamical transition which is characterized by a redistribution of the phonon modes from a oating to a pinned state, analogous to the Aubry transition of the static model.