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arXiv · 1208.1110

Soft deformable self-propelled particles

Andreas M. Menzel·Takao Ohta
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Abstract

In this work we investigate the collective behavior of self-propelled particles that deform due to local pairwise interactions. We demonstrate that this deformation alone can induce alignment of the velocity vectors. The onset of collective motion is analyzed. Applying a Gaussian-core repulsion between the particles, we find a transition to disordered non-collective motion under compression. We here explain that this reflects the reentrant fluid behavior of the general Gaussian-core model now applied to a self-propelled system. Truncating the Gaussian potential can lead to cluster crystallization or more disordered cluster states. For intermediate values of the Gaussian-core potential we for the first time observe laning for deformable self-propelled particles. Finally, without the core potential, but including orientational noise, we connect our description to the Vicsek approach for self-propelled particles with nematic alignment interactions.

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Andreas M. Menzel, Takao Ohta. 2012-08-06. Soft deformable self-propelled particles. https://doi.org/10.1209/0295-5075%2F99%2F58001

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