Short-wavelength collective modes in a binary hard-sphere mixture

TL;DR

This paper presents an analytic theory of collective modes in dense binary mixtures using generalized hydrodynamics, aligning qualitatively with molecular dynamics results and offering insights into glass formation.

Contribution

It introduces a simple analytic description of collective excitations in dense binary mixtures at molecular scales, highlighting the role of compositional disorder.

Findings

Qualitative agreement with molecular dynamics results

Insight into the role of compositional disorder in glass formation

Analytic framework for collective modes in binary mixtures

Abstract

We use hard-sphere generalized hydrodynamic equations to discuss the extended hydrodynamic modes of a binary mixture. The theory presented here is analytic and it provides us with a simple description of the collective excitations of a dense binary mixture at molecular length scales. The behavior we predict is in qualitative agreement with molecular-dynamics results for soft-sphere mixtures. This study provides some insight into the role of compositional disorder in forming glassy configurations.