Aspect-ratio-dependent void formation in active rhomboidal and elliptical particle systems

Area of Science:

• Soft matter physics
• Computational fluid dynamics
• Materials science

Background:

• Active nematics exhibit complex behaviors driven by self-propelled particles.
• Understanding particle shape effects on emergent phenomena like void formation is crucial.
• Excluded-volume interactions significantly influence particle packing and dynamics.

Purpose of the Study:

• To investigate void formation in active nematics with rhomboidal and elliptical particles.
• To analyze the relationship between void regions and particle orientation.
• To determine how particle aspect ratio affects void characteristics and dynamics.

Main Methods:

• Numerical simulations of active nematics with excluded-volume interactions.
• Analysis of particle number density, orientation, topological defects, and void regions.
• Comparison of systems with rhomboidal and elliptical particle shapes at varying aspect ratios.

Main Results:

• Void regions appear in both rhomboidal and elliptical particle systems at high aspect ratios.
• Rhomboidal systems exhibit characteristic void sizes increasing with aspect ratio.
• Elliptical systems show a broad distribution of void sizes, potentially limited by system size.

Conclusions:

• Void size in rhomboidal active nematics is linked to orientational field correlation length.
• Void size in elliptical active nematics may be constrained by overall system dimensions.
• Particle shape critically influences void formation and characteristics in active nematic systems.