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Updated: Jul 5, 2025
08:37
Forming, Confining, and Observing Microtubule-Based Active Nematics
Published on: January 13, 2023
2.7K
Viscoelastic confinement induces periodic flow reversals in active nematics
Francesco Mori1, Saraswat Bhattacharyya1, Julia M Yeomans1
1Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford OX1 3PU, United Kingdom.
Physical Review. E
|January 20, 2024
Summary
Active nematics confined in viscoelastic channels exhibit instability at high activity. Below a critical elasticity, spontaneous oscillations and flow reversals occur due to the interplay between activity and viscoelasticity.
Area of Science:
- Soft Matter Physics
- Active Matter Dynamics
- Non-equilibrium Systems
Background:
- Active nematics are complex fluids with self-propulsion.
- Confining active matter influences its emergent behaviors.
- Viscoelastic materials exhibit both viscous and elastic properties.
Purpose of the Study:
- Investigate the dynamical behavior of active nematics in viscoelastic channels.
- Determine the conditions leading to instability and pattern formation.
- Explore the role of viscoelasticity in controlling active matter dynamics.
Main Methods:
- Linear stability analysis to identify instability thresholds.
- Hybrid lattice Boltzmann simulations for dynamical simulations.
- Phase diagram construction to map different dynamical regimes.
Main Results:
- An ordered active nematic becomes unstable above a critical activity level.
- High channel elasticity leads to a steady flow state.
- Below a threshold elastic modulus, spontaneous oscillations and periodic flow reversals emerge.
Conclusions:
- The interplay of activity and viscoelasticity drives spontaneous oscillations.
- Viscoelastic confinement is crucial for spatiotemporal organization in active matter.
- Results suggest experimental avenues for controlling active matter.
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