Defect-Mediated Phase Transitions in Active Soft Matter

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 thermal system---without creating topological defects.

23 pages, 3+7 figures

References in corpus (6)

• Novel type of phase transition in a system of self-driven particles
• Spontaneous motion in hierarchically assembled active matter
• Collective motion of self-propelled particles interacting without cohesion
• Hydrodynamic equations for self-propelled particles: microscopic derivation and stability analysis
• Consensus of self-driven agents with avoidance of collisions
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Cited by in corpus (7)

• Tuned, driven, and active soft matter
• Dynamical mean-field theory and weakly non-linear analysis for the phase separation of active Brownian particles
• Probing the shear viscosity of an active nematic
• Extreme Spontaneous Deformations of Active Crystals
• Gaussian theory for spatially distributed self-propelled particles
• Repulsive torques alone trigger crystallization of constant speed active particles
• Bidirectional Zigzag Growth from Clusters of Active Colloidal Shakers