Defect-Mediated Phase Transitions in Active Soft Matter

Authored by Christoph A Weber, Christopher Bock, Erwin Frey

Date Published: 2014

DOI: 10.1103/physrevlett.112.168301

Sponsors: German Research Foundation (Deutsche Forschungsgemeinschaft, DFG)

Platforms: No platforms listed

Model Documentation: Other Narrative

Model Code URLs: Model code not found

Abstract

How do topological defects affect the degree of order in active matter? To answer this question we investigate an agent-based model of self-propelled particles, which accounts for polar alignment and short-ranged repulsive interactions. For strong alignment forces we find collectively moving polycrystalline states with fluctuating networks of grain boundaries. In the regime where repulsive forces dominate, the fluctuations generated by the active system give rise to quasi-long-range transitional order, but-unlike the thermal system-without creating topological defects.
Tags
Model Motion Long-range order 2 dimensions Filaments