Related Experiment Video
Updated: May 11, 2025
08:37
Forming, Confining, and Observing Microtubule-Based Active Nematics
Published on: January 13, 2023
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Turbulence-to-order transitions in activity-patterned active nematics.
Cody D Schimming1,2, C J O Reichhardt2, C Reichhardt2
1Johns Hopkins University, Department of Physics and Astronomy, Baltimore, Maryland 21218, USA.
Physical Review. E
|April 18, 2025
Summary
We numerically explored active nematics with patterned activity. Increasing activity force and stripe distance induced transitions from 2D to 1D turbulence, leading to ordered vortices. Patterning geometry dictates vortex ordering.
Area of Science:
- Soft Matter Physics
- Non-equilibrium Statistical Mechanics
- Active Matter Systems
Background:
- Active nematics exhibit complex dynamic behaviors like turbulence.
- Periodic patterning of activity offers a route to control these behaviors.
- Understanding the interplay between activity patterns and emergent order is crucial.
Purpose of the Study:
- To investigate the effects of periodic activity patterning on two-dimensional active nematics.
- To explore transitions between different dynamic regimes (turbulence, ordered vortices).
- To determine the influence of patterning geometry on emergent phenomena.
Main Methods:
- Numerical simulations of two-dimensional active nematic systems.
- Systematic variation of activity force, stripe distance, and patterning geometry (stripes vs. circles).
- Analysis of emergent turbulence and vortex ordering dynamics.
Main Results:
- Observed transitions from 2D to 1D active turbulence with increasing activity force and stripe separation.
- Identified stable vortex phases with specific antiferromagnetic and ferromagnetic ordering.
- Found that transitions to 2D turbulence depend on active length scale and density, not geometry.
- Demonstrated that vortex ordering is highly sensitive to patterning geometry.
Conclusions:
- Periodic activity inhomogeneity can induce non-equilibrium phase transitions in active nematics.
- The geometry of activity patterning critically controls emergent vortex order.
- This work provides a mechanism for designing active matter systems with tailored properties.
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