Single-Particle Dynamics in Dense Granular Fluids under Driving

TL;DR

This paper develops a mode-coupling theory to describe the dynamics of a single particle in a dense, driven granular fluid near the glass transition, highlighting the effects of dissipation on structural arrest.

Contribution

It introduces a novel theoretical framework that accounts for dissipation effects in granular fluids, extending traditional models of glassy dynamics to nonelastic particles.

Findings

Mean-squared displacement shows a plateau indicating structural arrest.

Localization length and critical dynamics depend on dissipation degree.

Glass structure and dynamics are nonuniversal with respect to restitution coefficient epsilon.

Abstract

We present a mode-coupling theory for the dynamics of a tagged particle in a driven granular fluid close to the glass transition. The mean-squared displacement is shown to exhibit a plateau indicating structural arrest. In contrast to elastic hard-sphere fluids, which are solely controlled by volume fraction, the localisation length as well as the critical dynamics depend on the degree of dissipation, parametrized by the coefficient of normal restitution epsilon. Hence the resulting glassy structure as well as the critical dynamics are nonuniversal with respect to epsilon.