Colloidal systems with competing interactions: from an arrested repulsive cluster phase to a gel

TL;DR

This study uses numerical simulations to explore how colloidal particles with competing attractions and repulsions form either stable clusters or gels, revealing two distinct arrested states in the phase diagram.

Contribution

It provides a detailed numerical analysis of phase behavior in colloids with competing interactions, identifying two non-ergodic arrested states: cluster glasses and gels.

Findings

Identification of stable finite-size clusters dominated by repulsion

Discovery of a percolating gel state at low temperatures

Evidence of two distinct non-ergodic states: cluster glass and gel

Abstract

We report an extensive numerical study of a charged colloidal system with competing short-range depletion attraction and long-range electrostatic repulsion. By analizing the cluster properties, we identify two distinct regions in the phase diagram: a state composed of stable finite-size clusters, whose relative interactions are dominated by long-range repulsion, and a percolating network. Both states are found to dynamically arrest at low temperatures, providing evidence of the existence of two distinct non-ergodic states in these systems: a Wigner glass of clusters and a gel.