Dynamical phase diagram of the dc-driven underdamped Frenkel-Kontorova chain

TL;DR

This paper investigates the complex dynamical phase transitions in an underdamped Frenkel-Kontorova chain driven by a DC force, revealing how the transition hierarchy depends on friction and providing a phenomenological explanation.

Contribution

It presents a detailed MD simulation study of the dynamical phase diagram of the underdamped Frenkel-Kontorova model, highlighting the friction dependence of transition hierarchies.

Findings

Hierarchy of phase transitions depends on friction constant

Critical forces vary with friction, affecting transition regimes

A phenomenological model explains friction's role in transitions

Abstract

Multistep dynamical phase transition from the locked to the running state of atoms in response to a dc external force is studied by MD simulations of the generalized Frenkel-Kontorova model in the underdamped limit. We show that the hierarchy of transition recently reported [Braun et al, Phys. Rev. Lett. 78, 1295 (1997)] strongly depends on the value of the friction constant. A simple phenomenological explanation for the friction dependence of the various critical forces separating intermediate regimes is given.