Decoupling of single-particle and collective dynamics in arrested phase-separating glassy mixtures

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Moser, Konstantin N., Likos, Christos N., Sposini, Vittoria
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915723981357056
author Moser, Konstantin N.
Likos, Christos N.
Sposini, Vittoria
author_facet Moser, Konstantin N.
Likos, Christos N.
Sposini, Vittoria
contents We investigate the structure and dynamics of a hard colloid-star polymer mixture in the range of its arrested phase separation, where an incipient demixing transition is interfering with a nearby vitrification line, focusing on the protein limit (smaller hard component). Soft-hard mixtures present a rich dynamics, influenced by different parameters such as the concentration of the soft and hard components, the softness of the potential, and the size ratio between the two components. Using coarse-grained molecular dynamics simulations, we characterize the single-particle and collective dynamics of the hard colloidal tracers in the soft glassy matrix. The hard tracers show diffusive behavior of the mean squared displacement accompanied by non-exponential relaxation of the intermediate scattering functions at intermediate length scales and non-Gaussian displacement distributions. Moreover, we show that the system exhibits arrested phase separation, leading to population splitting and decoupling between self- and collective dynamics of the hard colloids. Overall, we demonstrate that the interplay between arrested phase separation and glassiness leads to complex, multiscale phenomena that strongly influence the dynamics of the hard additives in the arrested matrix formed by the soft colloids.
format Preprint
id arxiv_https___arxiv_org_abs_2601_07625
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Decoupling of single-particle and collective dynamics in arrested phase-separating glassy mixtures
Moser, Konstantin N.
Likos, Christos N.
Sposini, Vittoria
Soft Condensed Matter
Statistical Mechanics
We investigate the structure and dynamics of a hard colloid-star polymer mixture in the range of its arrested phase separation, where an incipient demixing transition is interfering with a nearby vitrification line, focusing on the protein limit (smaller hard component). Soft-hard mixtures present a rich dynamics, influenced by different parameters such as the concentration of the soft and hard components, the softness of the potential, and the size ratio between the two components. Using coarse-grained molecular dynamics simulations, we characterize the single-particle and collective dynamics of the hard colloidal tracers in the soft glassy matrix. The hard tracers show diffusive behavior of the mean squared displacement accompanied by non-exponential relaxation of the intermediate scattering functions at intermediate length scales and non-Gaussian displacement distributions. Moreover, we show that the system exhibits arrested phase separation, leading to population splitting and decoupling between self- and collective dynamics of the hard colloids. Overall, we demonstrate that the interplay between arrested phase separation and glassiness leads to complex, multiscale phenomena that strongly influence the dynamics of the hard additives in the arrested matrix formed by the soft colloids.
title Decoupling of single-particle and collective dynamics in arrested phase-separating glassy mixtures
topic Soft Condensed Matter
Statistical Mechanics
url https://arxiv.org/abs/2601.07625