Active Jamming: Self-propelled soft particles at high density

TL;DR

This paper investigates the collective behavior of dense, self-propelled soft particles, revealing phase transitions between liquid and jammed states influenced by particle density and propulsion speed, with implications for biological cell layers.

Contribution

It introduces a numerical study of active jamming in self-propelled soft particles, connecting phase behavior to experimental biological systems.

Findings

Liquid phase with giant fluctuations at low density and high propulsion

Jammed phase occurs at high density and low propulsion

Jammed dynamics are governed by low frequency modes

Abstract

We study numerically the phases and dynamics of a dense collection of self-propelled particles with soft repulsive interactions in two dimensions. The model is motivated by recent in vitro experiments on confluent monolayers of migratory epithelial and endothelial cells. The phase diagram exhibits a liquid phase with giant number fluctuations at low packing fraction and high self-propulsion speed and a jammed phase at high packing fraction and low self-propulsion speed. The dynamics of the jammed phase is controlled by the low frequency modes of the jammed packing.