Noise activated granular dynamics

TL;DR

This paper investigates the dynamics of two inelastically colliding particles in a bistable potential driven by stochastic noise, revealing how granular temperature influences clustering, hopping behavior, and the effects of inelasticity on particle transitions.

Contribution

It introduces a model of granular particles in a bistable potential, demonstrating how granular temperature replaces thermal temperature in hopping rates and showing different hopping scenarios based on inelasticity.

Findings

Hopping over the barrier follows an Arrhenius-like rate with granular temperature.

Particles tend to cluster at low driving and fill space at high temperature.

Inelasticity affects whether particles hop individually or simultaneously.

Abstract

We study the behavior of two particles moving in a bistable potential, colliding inelastically with each other and driven by a stochastic heat bath. The system has the tendency to clusterize, placing the particles in the same well at low drivings, and to fill all of the available space at high temperatures. We show that the hopping over the potential barrier occurs following the Arrhenius rate, where the heat bath temperature is replaced by the granular temperature. Moreover, within the clusterized ``phase'' one encounters two different scenarios: for moderate inelasticity, the jumps from one well to the other involve one particle at a time, whereas for strong inelasticity the two particles hop simultaneously.