Barrier crossing in a viscoelastic bath

TL;DR

This paper studies how a colloidal particle crosses a barrier in a viscoelastic environment, revealing two distinct time scales affecting hopping dynamics and showing that elastic energy storage accelerates barrier crossing.

Contribution

It demonstrates the existence of two separate time scales in barrier crossing within a viscoelastic bath and links the shorter scale to elastic energy dynamics, supported by numerical simulations.

Findings

Two distinct waiting time scales identified

Shorter time scale linked to elastic energy relaxation

Hopping rate increases due to elastic energy storage

Abstract

We investigate the hopping dynamics of a colloidal particle across a potential barrier and within a viscoelastic, i.e., non-Markovian bath, and report two clearly separated time scales in the corresponding waiting time distributions. While the longer time scale exponentially depends on the barrier height, the shorter one is similar to the relaxation time of the fluid. This short time scale is a signature of the storage and release of elastic energy inside the bath, that strongly increases the hopping rate. Our results are in excellent agreement with numerical simulations of a simple Maxwell model.