English

Simultaneous Phase Separation and Pattern Formation in Chiral Active Mixtures

Soft Condensed Matter 2019-07-24 v1 Statistical Mechanics

Abstract

Chiral active particles, or self-propelled circle swimmers, from sperm cells to asymmetric Janus colloids, form a rich set of patterns, which are different from those seen in linear swimmers. Such patterns have mainly been explored for identical circle swimmers, while real-world circle swimmers, typically possess a frequency distribution. Here we show that even the simplest mixture of (velocity-aligning) circle swimmers with two different frequencies, hosts a complex world of superstructures: The most remarkable example comprises a microflock pattern, formed in one species, while the other species phase separates and forms a macrocluster, coexisting with a gas phase. Here, one species microphase-separates and selects a characteristic length scale, whereas the other one macrophase separates and selects a density. A second notable example, here occurring in an isotropic system, are patterns comprising two different characteristic length scales, which are controllable via frequency and swimming speed of the individual particles.

Keywords

Cite

@article{arxiv.1901.08496,
  title  = {Simultaneous Phase Separation and Pattern Formation in Chiral Active Mixtures},
  author = {Demian Levis and Benno Liebchen},
  journal= {arXiv preprint arXiv:1901.08496},
  year   = {2019}
}
R2 v1 2026-06-23T07:21:21.037Z