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Updated: Mar 22, 2026
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Visually Based Characterization of the Incipient Particle Motion in Regular Substrates: From Laminar to Turbulent Conditions
Published on: February 22, 2018
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Nucleation pathway and kinetics of phase-separating active Brownian particles
David Richard1, Hartmut Löwen, Thomas Speck
1Institut für Physik, Johannes Gutenberg-Universität Mainz, Staudingerweg 7-9, 55128 Mainz, Germany. thomas.speck@uni-mainz.de.
Soft Matter
|April 30, 2016
Summary
Self-propelled particles can phase separate like passive particles. Simulations reveal nucleation kinetics and pathways for active Brownian disks, suggesting an effective free energy governs this phenomenon.
Area of Science:
- Physics
- Soft Matter Physics
- Statistical Mechanics
Background:
- Self-propelled particles exhibit complex behaviors, including phase separation, mimicking passive systems.
- Understanding active Brownian motion is crucial for fields like robotics and biological systems.
Purpose of the Study:
- To investigate the nucleation kinetics and microscopic pathways of phase separation in active Brownian disks.
- To determine if an effective free energy governs the phase separation of self-propelled particles.
Main Methods:
- Utilizing two-dimensional computer simulations.
- Quenching homogeneous suspensions of active Brownian disks to propulsion speeds beyond the binodal.
- Employing committor analysis to study transition states.
Main Results:
- Observed qualitative behavior of nucleation rate versus density similar to passive liquid-vapor separation.
- Demonstrated that an effective free energy scenario extends to the kinetics of active particle phase separation.
- Identified cluster size and radial polarization as key descriptors for transition states.
Conclusions:
- Phase separation in purely repulsive, self-propelled Brownian particles shares similarities with passive systems.
- The kinetics of active Brownian disk phase separation can be described by an effective free energy.
- Cluster size and particle polarization are critical factors in the phase separation transition.
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