Non-equilibrium solvent dynamics due to time-dependent temperature gradient around laser-heated colloids

Laser illumination of a Janus colloid which is suspended in a near-critical binary solvent leads to the formation of a concentration gradient and coarsening patterns around the colloid, which leads to its phoretic motion. Using analytical theory and numerical simulations, we investigate this non-equilibrium phenomenon under the influence of a time-dependent temperature gradient. Time-dependent properties of the coarsening patterns for various surface adsorption properties of the Janus colloid are analyzed. We also present results for structure formation around colloidal particles kept confined in thin films with confining surfaces preferring one species of the binary liquid mixture over the other. Confinement leads to the formation of a bridge connecting the colloid and both the confining walls.