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Non-equilibrium dynamics of an active colloidal "chucker"
C Valeriani1, R J Allen, D Marenduzzo
1SUPA, School of Physics and Astronomy, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ, Scotland. cvaleria@ph.ed.ac.uk
The Journal of Chemical Physics
|June 3, 2010
Summary
Colloidal chuckers emit particles, initially boosting their diffusion. At high emission rates, crowding slows them down. This study explores chucker dynamics and interactions with surfaces.
Area of Science:
- Colloid and Surface Science
- Statistical Mechanics
- Computational Physics
Background:
- Colloidal particles emitting solutes (chuckers) are inspired by biological systems like bacteria.
- Recent work explores phoretic colloidal swimmers and their dynamics.
Purpose of the Study:
- Investigate the dynamics of colloidal chuckers using Monte Carlo simulations.
- Analyze how particle emission rate affects chucker diffusion and mobility.
- Characterize chucker behavior near surfaces with varying solute interactions.
Main Methods:
- Monte Carlo simulations of chucker dynamics.
- Analytical calculation of solute concentration fields.
- Langevin dynamics simulations for coarse-grained hydrodynamic effects.
- Simulations of chucker dragging to estimate mobility.
Main Results:
- Chucker diffusion constant increases at low emission rates (k(c)), consistent with theory.
- At high k(c), diffusion slows due to crowding effects.
- Apparent mobility coefficient violates the fluctuation-dissipation theorem.
- Steady-state distributions near surfaces differ significantly for repelling vs. absorbing solute interactions.
Conclusions:
- Chucker dynamics are complex, influenced by emission rate and particle interactions.
- Simulations provide insights into anomalous diffusion and surface interactions of active colloids.
- Findings contribute to understanding self-propelled and interacting colloidal systems.
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