Static structure of active Brownian hard disks

Area of Science:

• Condensed matter physics
• Statistical mechanics
• Soft matter physics

Background:

• Active Brownian particles (ABP) are fundamental models for self-propelled entities.
• Understanding their collective behavior, like phase separation, is crucial in soft matter.
• Static structure is key to characterizing fluid phases.

Purpose of the Study:

• Investigate structural ordering in 2D ABP systems.
• Analyze the influence of self-propulsion velocity and rotational diffusivity.
• Provide reference data for theoretical models of active matter.

Main Methods:

• Event-driven Brownian dynamics simulations.
• Analysis of the orientationally-averaged fluid structure factor.
• System: two-dimensional active Brownian particles with hard-disk interactions.

Main Results:

• Activity enhances structural ordering in the system.
• A structure factor peak emerges at zero wave vector.
• This peak indicates a precursor to motility-induced phase separation.

Conclusions:

• Simulation results offer valuable data for validating statistical theories.
• The study clarifies the role of activity in ABP structural organization.
• Findings contribute to the understanding of active matter phase behavior.