Influence of interaction softness in phase separation of active particles

Abstract

Using a minimal model of active Brownian discs, we study the effect of a crucial parameter, namely the softness of the inter-particle repulsion, on motility-induced phase separation. We show that an increase in particle softness reduces the ability of the system to phase-separate and the system exhibit a delayed transition. After phase separation, the system state properties can be explained by a single relevant lengthscale, the effective inter-particle distance. We estimate this lengthscale analytically and use it to rescale the state properties at dense phase for systems with different interaction softness. Using this lengthscale, we provide a scaling relation for the time taken to phase separate which shows a high sensitivity to the interaction softness.

arXiv comment8 pages, 12 figures. Significant changes: The form of the critical radius rc is new, with a better physical understanding of the system. Which neither changes the scaling nor the exponenets of the system. Fig.11 is a new addition in the appendix

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Cited by in corpus (7)

• Motility induced phase separation of deformable cells
• Percolation transition in phase separating active fluid
• Dynamical anomalies and structural features of Active Brownian Particles characterised by two repulsive length scales
• Active wetting transitions induced by rotational noise at solid interfaces
• Percolation transitions in the binary mixture of active Brownian particles with different softness
• Effective interactions in active Brownian particles
• Effect of the background flow on the motility induced phase separation