Dynamics in the Metabasin Space of a Lennard-Jones Glass Former: Connectivity and Transition Rates

TL;DR

This study uses simulations to analyze the effective Markovian dynamics in metabasin space of a Lennard-Jones glass, highlighting the importance of connectivity for understanding slow relaxation.

Contribution

It introduces a scheme to identify metabasins based on transition rates and demonstrates the significance of connectivity in modeling glassy dynamics.

Findings

Effective metabasin dynamics are Markovian.

Connectivity is crucial for reproducing slow dynamics.

Differences from simple trap models are significant.

Abstract

Using simulations, we construct the effective dynamics in metabasin space for a Lennard-Jones glass-former. Metabasins are identified via a scheme that measures transition rates between inherent structures, and generates clusters of inherent structures by drawing in branches that have the largest transition rates. The effective dynamics is shown to be Markovian but differs significantly from the simplest trap models. We specifically show that retaining information about the connectivity in metabasin space is crucial for reproducing the slow dynamics observed in this system.