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Updated: May 18, 2026
08:37
Forming, Confining, and Observing Microtubule-Based Active Nematics
Published on: January 13, 2023
Nucleation-induced transition to collective motion in active systems
Christoph A Weber1, Volker Schaller, Andreas R Bausch
1Arnold Sommerfeld Center for Theoretical Physics and Center for NanoScience, Department of Physics, Ludwig-Maximilians-Universität München, 80333 Munich, Germany.
Summary
The study reveals how active systems self-assemble into polar ordered states. This transition is driven by nucleation and coarsening, with ordering time showing a power-law divergence.
Area of Science:
- Physics
- Soft Matter Physics
- Statistical Mechanics
Background:
- Polar ordered states are known in active systems.
- The dynamics of self-assembly into these states remain unclear.
Purpose of the Study:
- Investigate the dynamics of self-assembly in active systems.
- Characterize the phase transition from isotropic to polar order.
Main Methods:
- Utilized a lattice gas model.
- Simulated self-propelled elongated particles with excluded volume and alignment interactions.
Main Results:
- Observed a phase transition from isotropic to polar ordered state.
- Identified nucleation and coarsening as key drivers of ordering.
- Found a power-law divergence in the time to establish polar order.
Conclusions:
- The self-assembly dynamics are governed by nucleation and coarsening.
- Ordering time in active systems exhibits predictable scaling behavior.
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