Anomalous diffusion of symmetric and asymmetric active colloids.
The stochastic dynamics of colloidal particles with surface activity-in the form of catalytic reaction or particle release-and self-phoretic effects are studied analytically. Three different time scales corresponding to inertial effects, solute redistribution, and rotational diffusion are identified and shown to lead to a plethora of different regimes involving inertial, propulsive, anomalous, and diffusive behaviors. For symmetric active colloids, a regime is found where the mean-squared displacement has a superdiffusive t;{3/2} behavior. At the longest time scales, an effective diffusion coefficient is found which has a nonmonotonic dependence on the size of the colloid.
Golestanian
Ramin
R
Department of Physics, University of Sheffield, Sheffield S3 7RH, United Kingdom. r.golestanian@sheffield.ac.uk
D000465:Algorithms; D003102:Colloids / Q000737:chemistry*; D004058:Diffusion; D007700:Kinetics; D008956:Models, Chemical; D009038:Motion; D013269:Stochastic Processes; D013501:Surface-Active Agents / Q000737:chemistry*; D013816:Thermodynamics; D014867:Water / Q000737:chemistry
D003102:Colloids; D013501:Surface-Active Agents; D014867:Water