Glassy dynamics in monodisperse hard ellipsoids

TL;DR

This paper provides simulation evidence that monodisperse hard ellipsoids can exhibit glassy dynamics due to particle anisometry, challenging the usual requirement of polydispersity for glass formation.

Contribution

It demonstrates that slight particle anisometry alone can induce glassy behavior in monodisperse systems, expanding understanding of glass formation mechanisms.

Findings

Super-Arrhenius slowing down of diffusion and relaxation.

Two-step relaxation in positional and orientational correlators.

Mode-coupling theory applies to these glassy dynamics.

Abstract

We present evidence from computer simulations for glassy dynamics in suspensions of monodisperse hard ellipsoids. In equilibrium, almost spherical ellipsoids show a first order transition from an isotropic phase to a rotator phase. When overcompressing the isotropic phase into the rotator regime, we observe super-Arrhenius slowing down of diffusion and relaxation, accompanied by two-step relaxation in positional and orientational correlators. The effects are strong enough for asymptotic laws of mode-coupling theory to apply. Glassy dynamics are unusual in monodisperse systems. Typically, polydispersity in size or a mixture of particle species is prerequisite to prevent crystallization. Here, we show that a slight particle anisometry acts as a sufficient source of disorder. This sheds new light on the question of which ingredients are required for glass formation.