Related Experiment Video
Updated: Nov 30, 2025

Forming, Confining, and Observing Microtubule-Based Active Nematics
Published on: January 13, 2023
Dry Active Matter Exhibits a Self-Organized Cross Sea Phase
Rüdiger Kürsten1, Thomas Ihle1
1Institut für Physik, Universität Greifswald, Felix-Hausdorff-Straße 6, 17489 Greifswald, Germany.
Abstract:
The Vicsek model of self-propelled particles is known in three different phases: a polar ordered homogeneous phase, also called the Toner-Tu phase, a phase of polar ordered regularly arranged high density bands with surrounding low density regions without polar order, and a homogeneous phase without polar order. Here, we show that the standard Vicsek model has a fourth phase for large system sizes: a polar ordered cross sea phase. We demonstrate that the cross sea phase is not just a superposition of two waves, but it is an independent complex pattern with an inherently selected crossing angle.
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