Motile dissenters disrupt the flocking of active granular matter

Abstract

We report flocking in the dry active granular matter of millimeter-sized two-step-tapered rods without an intervening medium. The system undergoes the flocking phase transition at a threshold area fraction ~ 0.12 having high orientational correlations between the particles. However, the one-step-tapered rods do not flock and are used as the motile dissenters in the flock-forming granular matter. At the critical fraction of dissenters ~ 0.3, the flocking order of the system gets completely destroyed. The variance of the system's order parameter shows a maximum near the dissenter fraction f ~ 0.05, suggesting a finite-size crossover between the ordered and disordered phases.

arXiv comment11 pages, 4 figures

References in corpus (14)

• Long-lived Giant Number Fluctuations in a Swarming Granular Nematic
• Flocking at a distance in active granular matter
• Spontaneous Segregation of Self-Propelled Particles with Different Motilities
• Distortion and destruction of colloidal flocks in disordered environments
• Optimal noise maximizes collective motion in heterogeneous media
• Dynamic Phases of Active Matter Systems with Quenched Disorder
• Symmetry properties of the large-deviation function of the velocity of a self-propelled polar particle
• Sorting motile rods by activity
• Trapping and sorting active particles: motility-induced condensation & smectic defects
• How many dissenters does it take to disorder a flock?
• Clogging and Depinning of Ballistic Active Matter Systems in Disordered Media
• Polar flock in the presence of random quenched rotators
• Gregarious vs Individualistic Behavior in Vicsek Swarms and the Onset of First-Order Phase Transitions
• Dry, aligning, dilute, active matter: A synthetic and self-contained overview

Cited by in corpus (8)

• Chemotactic smoothing of collective migration
• Flocking of two unfriendly species: The two-species Vicsek model
• Heterogeneous bacterial swarms with mixed lengths
• Emergent complex phases in a discrete flocking model with reciprocal and non-reciprocal interactions
• Bulk condensation by an active interface
• Stability of flocking in the reciprocal two-species Vicsek model: Effects of relative population, motility, and noise
• Reentrant phase behavior in binary topological flocks with nonreciprocal alignment
• Susceptibility of Orientationally-Ordered Active Matter to Chirality Disorder