Chaotic and periodical dynamics of active chiral droplets

Abstract

The interplay between the chirality of many biological molecules and the energy injected at small length-scales as the result of biological processes is at the base of the life of the cells. With the aim of unveiling the connection between these two features, here we analyze by means of lattice Boltzmann simulations the behavior of an active droplet of cholesteric liquid crystal under the effect of intense active doping, within the framework of active gel theory. We find that a droplet of chiral liquid crystal, fueled by active force dipoles, develops defect loops (closed disclination lines) that pierce the interior of the droplet, leading the droplet to develop an erratic motility mode. When the droplet is fueled by in-warding active torque dipoles, three different dynamical regimes develops at varying both the thermodynamic chirality and the strength of active energy injection: a stable rotational state at low activity, an intermittent disclination dance regime, and a turbulent state where closed disclination lines formation is inhibited and new pairs of oppositely charged surface defects leads to the development of chaotic rotational motion. Finally, we show that out-warding torque dipoles are able to sustain a periodical dynamics at higher chirality characterized by the nucleation/annihilation of pairs of disclination rings.

References in corpus (22)

• Novel type of phase transition in a system of self-driven particles
• Active Particles in Complex and Crowded Environments
• The Mechanics and Statistics of Active Matter
• Motility-Induced Phase Separation
• Physics of Microswimmers - Single Particle Motion and Collective Behavior
• Hydrodynamic fluctuations and instabilities in ordered suspensions of self-propelled particles
• Pattern formation in self-propelled particles with density-dependent motility
• Spontaneous symmetry breaking in active droplets provides a generic route to motility
• Spontaneous Segregation of Self-Propelled Particles with Different Motilities
• Biphasic, Lyotropic, Active Nematics
• A minimal physical model captures the shapes of crawling cells
• Motility-induced phase separation and coarsening in active matter
• Active turbulence in active nematics
• Hybrid lattice Boltzmann model for binary fluid mixtures
• Phase co-existence in bidimensional passive and active dumbbell systems
• Morphologies and flow patterns in quenching of lamellar systems with shear
• Lattice Boltzmann simulations of lamellar and droplet phases
• Scaling and hydrodynamic effects in lamellar ordering
• Dynamics of a homogeneous active dumbbell system
• Bistable defect structures in blue phase devices
• Ordering of the lamellar phase under a shear flow
• Thermal and hydrodynamic effects in the ordering of lamellar fluids

Cited by in corpus (11)

• Lattice Boltzmann Methods and Active Fluids
• Rotation and propulsion in 3d active chiral droplets
• Cascade or not cascade? Energy transfer and elastic effects in active nematics
• Multi-scale control of active emulsion dynamics
• Rheology of active polar emulsions: from linear to unidirectional and unviscid flow, and intermittent viscosity
• Phase-field-based lattice Boltzmann model for immiscible incompressible N-phase flows
• Soft channel formation and symmetry breaking in exotic active emulsions
• Activity induced isotropic-polar transition in active liquid crystals
• Rheology of active emulsions with negative effective viscosity
• Dynamically asymmetric and bicontinuous morphologies in active emulsions
• Motility and self propulsion of active droplets