Single-file dynamics of colloids in circular channels: Time scales, scaling laws and their universality

In colloidal systems, Brownian motion emerges from the massive separation of time and length scales associated to characteristic dynamics solute solvent constituents. This produces several temporal regimes in when combined with effects interaction between particles, confinement conditions, state variables, such as density temperature. Some examples are short- long-time two- three-dimensional open systems diffusive sub-diffusive observed single-file along a straight line. work studies way which confining geometry induces new scales. We report on interacting particles moving circle by combining heuristic theoretical analysis involved scales, Dynamics computer simulations, video-microscopy experiments paramagnetic colloids confined lithographic circular channels subjected an external magnetic field. The display four this order: one-dimensional free diffusion, sub-diffusion, free-cluster rotational expected saturation due confinement. also analytical expressions for mean-square angular displacement crossover times obtained scaling arguments, accurately reproduce both simulations. Our generic approach can be used predict many other physical systems.