Biomimetic swarm of active particles with coupled passive-active interactions

Area of Science:

• Soft Matter Physics
• Active Matter Systems
• Biomimetic Design

Background:

• Collective behavior in natural systems (fish schools, bird flocks) inspires synthetic systems.
• Active colloids with specific interaction designs can exhibit self-organization.
• Understanding universal behaviors in active matter is crucial for designing emergent properties.

Purpose of the Study:

• To investigate the universal behavior of active colloids designed with off-center repulsive interactions.
• To explore the self-organization into polar swarms and their emergent properties.
• To identify key parameters governing the phase transitions and collective dynamics.

Main Methods:

• Computational simulations were employed to model the active colloid system.
• Analysis of swarm polarity and hexatic bond order parameters was performed.
• Effective volume fractions, considering force and torque ranges, were calculated.

Main Results:

• Active colloids self-organize into polar swarms with long-range order and directional motion.
• The system exhibits transitions between crystalline, solid-like, liquid-like, and gas-like states based on noise, interaction strength, and density.
• Universal behavior is explained by effective volume fractions derived from interaction ranges.

Conclusions:

• The study demonstrates a biomimetic approach to active matter design, mimicking natural collective behaviors.
• Effective volume fractions provide a unifying framework for understanding the phase behavior of these active colloids.
• This research lays the foundation for developing applications based on cooperative polar dynamics in synthetic systems.