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arXiv · 1208.5448

Nucleation-induced transition to collective motion in active systems

Christoph. A. Weber·Volker Schaller·Andreas R. Bausch·Erwin Frey
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Abstract

While the existence of polar ordered states in active systems is well established, the dynamics of the self-assembly processes are still elusive. We study a lattice gas model of self-propelled elongated particles interacting through excluded volume and alignment interactions, which shows a phase transition from an isotropic to a polar ordered state. By analyzing the ordering process we find that the transition is driven by the formation of a critical nucleation cluster and a subsequent coarsening process. Moreover, the time to establish a polar ordered state shows a power-law divergence.

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Christoph. A. Weber, Volker Schaller, Andreas R. Bausch, Erwin Frey. 2012-08-27. Nucleation-induced transition to collective motion in active systems. https://doi.org/10.1103/physreve.86.030901

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