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Competing effects of rotational diffusivity and activity on finite-sized clusters
Ravi Thej Pilla1, Ethayaraja Mani1
1Polymer Engineering and Colloid Science Lab, Department of Chemical Engineering, Indian Institute of Technology Madras, Chennai-600036, India.
Summary
Self-propelled colloidal particles form stable clusters. Increasing activity initially increases cluster size, then decreases it, leading to a fluid transition. Rotational diffusivity stabilizes clusters at higher activities.
Area of Science:
- Soft Matter Physics
- Colloidal Science
- Statistical Mechanics
Background:
- Colloidal particles with competing interactions form equilibrium clusters.
- Understanding active matter dynamics is crucial for self-assembly.
Purpose of the Study:
- Investigate the influence of activity and rotational diffusivity on colloidal particle phase behavior.
- Characterize cluster formation and stability in active systems.
Main Methods:
- Brownian dynamics simulations were employed.
- Analysis of static structure factor was performed.
Main Results:
- Cluster size shows non-monotonic dependence on activity, initially increasing then decreasing.
- Higher rotational diffusivity stabilizes larger clusters and delays activity-induced fluid transition.
- Rich phase behavior with various cluster types was observed.
Conclusions:
- Activity and rotational diffusivity significantly alter colloidal phase behavior.
- Rotational diffusivity acts as a stabilizing factor against activity-driven cluster dissolution.
- These findings provide insights into self-assembly mechanisms in active colloidal systems.
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