Active nematic-isotropic interfaces in channels.

  title={Active nematic-isotropic interfaces in channels.},
  author={Rodrigo C. V. Coelho and Nuno A. M. Ara{\'u}jo and Margarida M. Telo da Gama},
  journal={Soft matter},
We use numerical simulations to investigate the hydrodynamic behavior of the interface between nematic (N) and isotropic (I) phases of a confined active liquid crystal. At low activities, a stable interface with constant shape and velocity is observed separating the two phases. For nematics in homeotropic channels, the velocity of the interface at the NI transition increases from zero (i) linearly with the activity for contractile systems and (ii) quadratically for extensile ones. Interestingly… 

Director alignment at the nematic–isotropic interface: elastic anisotropy and active anchoring

The results of the simulations reveal that the active anchoring dominates except at very low activities, when the interfaces are static, and it is found that the elastic anisotropy does not affect the dynamics but changes the active length that becomes anisotropic.

Propagation of active nematic-isotropic interfaces on substrates.

A hydrodynamic multiphase model is used to investigate the propagation of interfaces of active nematics on substrates and finds an activity dependent threshold, above which the turbulent active nematic forms isolated islands that shrink until the system becomes isotropic and below which theActive nematic expands, with a well defined propagating interface.

Lattice-Boltzmann simulation of free nematic-isotropic interfaces

We use a hybrid method of lattice Boltzmann and finite differences to simulate flat and curved interfaces between the nematic and isotropic phases of a liquid crystal described by the Landau-de

Fingering instability of active nematic droplets

  • Ricard Alert
  • Physics
    Journal of Physics A: Mathematical and Theoretical
  • 2022
From the mitotic spindle up to tissues and biofilms, many biological systems behave as active droplets, which often break symmetry and change shape spontaneously. Here, I show that active nematic

Braiding Dynamics in Active Nematics

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Swarming bacterial fronts: Dynamics and morphology of active swarm interfaces propagating through passive frictional domains

It is concluded that hydrodynamic and steric interactions enable different modes of surface dynamics, morphology and thus front invasion in swarming Serratia marcescens.

Oscillatory chiral flows in confined active fluids with obstacles

The authors combine experiments and simulations to investigate collective chiral states of a confined polar active fluid with scatterers and show the onset of three dynamic steady states.

Channel Confined Active Nematics



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