Mode coupling behavior of a Lennard Jones binary mixture: a comparison between bulk and confined phases

TL;DR

This study compares the dynamical behavior of a Lennard Jones binary mixture in bulk and confined phases under supercooling, highlighting the role of hopping in spatially correlated dynamics and their agreement with Mode Coupling theory.

Contribution

It provides a detailed comparison of bulk and confined glassy dynamics, emphasizing the impact of confinement on mode coupling and hopping mechanisms.

Findings

Confined systems show reduced spatially correlated dynamics due to hopping.

Both bulk and confined systems exhibit behavior consistent with Mode Coupling theory.

Hopping plays a significant role in the dynamical differences observed under confinement.

Abstract

We present a quantitative comparison at equivalent thermodynamical conditions of bulk and confined dynamical properties of a Lennard Jones binary mixture upon supercooling. Both systems had been previously found to display a behavior in agreement with the Mode Coupling theory of the evolution of glassy dynamics. Differences and analogies of behavior are discussed focusing in particular on the role of hopping in reducing spatially correlated dynamics in the confined system with respect to the bulk.