Active rotational dynamics of a self-diffusiophoretic colloidal motor

Abstract

The dynamics of a spherical chemically-powered synthetic colloidal motor that operates by a self-diffusiophoretic mechanism and has a catalytic domain of arbitrary shape is studied using both continuum theory and particle-based simulations. The motor executes active rotational motion when self-generated concentration gradients and interactions between the chemical species and colloidal motor surface break spherical symmetry. Local variations of chemical reaction rates on the motor catalytic surface with catalytic domain sizes and shapes provide such broken symmetry conditions. A continuum theoretical description of the active rotational motion is given, along with the results of particle-based simulations of the active dynamics. From these results a detailed description of the factors responsible for the active rotational dynamics can be given. Since active rotational motion often plays a significant part in the nature of the collective dynamics of many-motor systems and can be used to control motor motion in targeted cargo transport, our results should find applications beyond those considered here.

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Simulation of microswimmer hydrodynamics with multiparticle collision dynamics*

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Relaxation in a phase-separating two-dimensional active matter system with alignment interaction

“…Active matter systems are composed of self-propelled particles and are inherently non-equilibrium in nature [1][2][3][4][5][6][7][8]. These systems are of significant recent interest [9][10][11][12][13][14][15][16][17][18], particularly in connection with the clustering phenomena that are commonly observed in a variety of systems containing living entities. Examples of such systems are aplenty, bacterial colony [19], school of fish [20] and flock of birds [21] being some of the popular ones.…”