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arXiv · 1602.05271

Collective Motion of Self-Propelled Particles with Memory

Ken H. Nagai·Yutaka Sumino·Raul Montagne·Igor S. Aranson·Hugues Chaté
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Abstract

We show that memory, in the form of underdamped angular dynamics, is a crucial ingredient for the collective properties of self-propelled particles. Using Vicsek-style models with an Ornstein-Uhlenbeck process acting on angular velocity, we uncover a rich variety of collective phases not observed in usual overdamped systems, including vortex lattices and active foams. In a model with strictly nematic interactions the smectic arrangement of Vicsek waves giving rise to global polar order is observed. We also provide a calculation of the effective interaction between vortices in the case where a telegraphic noise process is at play, explaining thus the emergence and structure of the vortex lattices observed here and in motility assay experiments.

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Ken H. Nagai, Yutaka Sumino, Raul Montagne, Igor S. Aranson, Hugues Chaté. 2018-09-11. Collective Motion of Self-Propelled Particles with Memory. https://doi.org/10.1103/physrevlett.114.168001

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