Excitable Patterns in Active Nematics

Abstract

We analyze a model of mutually-propelled filaments suspended in a two-dimensional solvent. The system undergoes a mean-field isotropic-nematic transition for large enough filament concentrations and the nematic order parameter is allowed to vary in space and time. We show that the interplay between non-uniform nematic order, activity and flow results in spatially modulated relaxation oscillations, similar to those seen in excitable media. In this regime the dynamics consists of nearly stationary periods separated by "bursts" of activity in which the system is elastically distorted and solvent is pumped throughout. At even higher activity the dynamics becomes chaotic.

4 pages, 4 figures

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Cited by in corpus (63)

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• Patterning active materials with addressable soft interfaces
• Velocity Correlations in an Active Nematic
• Defect-mediated morphologies in growing cell colonies
• Viscoelastic control of spatiotemporal order in bacterial active matter
• Spontaneous Circulation of Confined Active Suspensions
• Instabilities and Topological Defects in Active Nematics
• Multiscale polar theory of microtubule and motor-protein assemblies
• Long-range Ordering of Vibrated Polar Disks
• Spontaneous division and motility in active nematic droplets
• Emergent states in dense systems of active rods: from swarming to turbulence
• Vorticity, Defects and Correlations in Active Turbulence
• Universal scaling of active nematic turbulence
• Swarming, swirling and stasis in sequestered bristle-bots
• Banding, Excitability and Chaos in Active Nematic Suspensions
• Confined active nematic flow in cylindrical capillaries
• Correlation lengths in hydrodynamic models of active nematics
• A classical nucleation theory description of active colloid assembly
• Active turbulence in active nematics
• Analytical structure, dynamics, and coarse-graining of a kinetic model of an active fluid
• Submersed Micropatterned Structures Control Active Nematic Flow, Topology and Concentration
• Confinement-induced self-organization in growing bacterial colonies
• Negative stiffness and modulated states in active nematics
• Polar Patterns in Active Fluids
• Antipolar ordering of topological defects in active liquid crystals
• Multiscale modeling and simulation of microtubule/motor protein assemblies
• Understanding dense active nematics from microscopic models
• The low noise phase of a 2d active nematic
• Emergent Structures in an Active Polar Fluid : dynamics of shape, scattering and merger
• Data-driven discovery of active nematic hydrodynamics
• Fast, scalable, and interactive software for Landau-de Gennes numerical modeling of nematic topological defects
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• Globally aligned states and hydrodynamic traffic jams in confined active suspensions
• Spectral energy analysis of bulk three-dimensional active nematic turbulence
• Defect Spirograph: Dynamical Behavior of Defects in Spatially Patterned Active Nematics
• Geometry and mechanics of microdomains in growing bacterial colonies
• Oscillatory settling in wormlike-micelle solutions: bursts and a long time scale
• Coexistence of active and hydrodynamic turbulence in two dimensional active nematics
• Active nematics with quenched disorder
• The role of advective inertia in active nematic turbulence
• Weakly nonlinear analysis of pattern formation in active suspensions
• Non-equilibrium systems have steady-state distributions and non-steady dynamics
• Vorticity phase separation and defect lattices in the isotropic phase of active liquid crystals
• Self-propulsion of an active polar drop
• Cells around the corner
• Broad-tailed force distributions and velocity ordering in a heterogeneous membrane model for collective cell migration
• Active nematic gel with quenched disorder
• Active fluids form system-spanning filamentary networks
• Quadrupolar active stress induces exotic phases of defect motion in active nematics
• Demonstration of the rotational viscosity transfer across scales in Navier-Stokes turbulence
• Active nematic response to a deformable body or boundary: elastic deformations and anchoring-induced flow
• Self-sustained oscillations of active viscoelastic matter
• The importance of being discrete -- An agent-based model for active nematics and more
• Global Existence and Regularity for the Active Liquid Crystal System
• Thin Films of Chiral Motors
• Active viscoelastic nematics with partial degree of order
• Machine Learning Forecasting of Active Nematics
• Global Weak Solutions for the Compressible Active Liquid Crystal System