Designing slower glasses by manipulating their local structure

TL;DR

This paper introduces a colloidal model that enhances icosahedral local structures to slow down glass dynamics, offering a new approach to designing materials with tailored glass-forming properties.

Contribution

It demonstrates that promoting specific local structures, like icosahedral symmetry, can significantly slow glass dynamics, providing a novel method for controlling glassy behavior.

Findings

Enhancing icosahedral local structures dramatically slows down dynamics.

Selective promotion of local environments can control dense glassy systems.

The model offers a pathway to design glasses with desired properties.

Abstract

Glasses remain an elusive and poorly understood state of matter. For example, it is not clear how we can design an efficient macroscopic glass former by tuning the properties of its microscopic building blocks. In this paper, we propose a simple directional colloidal model that reinforces the optimal icosahedral local structure of binary hard-sphere glasses. We show that only this specific symmetry results in a dramatic slowing down of the dynamics. Our results open the door to controlling the dynamics of dense glassy systems by selectively promoting specific local structural environments.