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Controlling Flow Speeds of Microtubule-Based 3D Active Fluids Using Temperature
Published on: November 26, 2019
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Particle anisotropy tunes emergent behavior in active colloidal systems.
Shannon E Moran1, Isaac R Bruss1, Philipp W A Schönhöfer1
1Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109, USA. sglotzerkjc@umich.edu.
Soft Matter
|January 12, 2022
Summary
Particle shape and force direction significantly influence active colloidal systems, affecting phase separation and emergent behaviors. Tuning anisotropy offers a route for controlling these complex systems.
Area of Science:
- Physics
- Soft Matter Physics
- Active Matter
Background:
- Particle anisotropy is known to influence collective behavior in active particle systems.
- Understanding these effects is crucial for designing and controlling active colloidal systems.
Purpose of the Study:
- To systematically investigate the impact of shape and active force director anisotropy on the collective behavior of 2D active colloidal systems.
- To explore how these anisotropies affect motility-induced phase separation (MIPS) and critical densities.
Main Methods:
- Computational investigation of a two-dimensional active colloidal system.
- Analysis of particle shape and active force director anisotropy.
- Quantification of collision efficiency and its relation to MIPS.
Main Results:
- Shape and force anisotropy can lead to critical densities lower or higher than those of isotropic disks.
- Particle anisotropy tunes collision efficiency, a key factor in MIPS.
- Phase-separated clusters exhibit local structures mirroring equilibrium densest packing.
Conclusions:
- A direct link exists between equilibrium packing and non-equilibrium cluster structure in self-propelled anisotropic particles.
- Tailoring particle shape and interactions provides a pathway for controlling emergent behaviors in active colloidal systems.
- Shape-controlled steric interactions offer a simple engineering approach for active colloidal systems.
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