title: Non-Gaussian statistics for the motion of self-propelled Janus particles: experiment versus theory.
abstract: Spherical Janus particles are one of the most prominent examples for active Brownian objects. Here, we study the diffusiophoretic motion of such microswimmers in experiment and in theory. Three stages are found: simple Brownian motion at short times, superdiffusion at intermediate times, and finally diffusive behavior again at long times. These three regimes observed in the experiments are compared with a theoretical model for the Langevin dynamics of self-propelled particles with coupled translational and rotational motion. Besides the mean square displacement also higher displacement moments are addressed. In particular, theoretical predictions regarding the non-Gaussian behavior of self-propelled particles are verified in the experiments. Furthermore, the full displacement probability distribution is analyzed, where in agreement with Brownian dynamics simulations either an extremely broadened peak or a pronounced double-peak structure is found, depending on the experimental conditions.
authors.affiliation: State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, CAS, Beijing 100190, People's Republic of China.
authors.forename: Xu
authors.initials: X
authors.lastname: Zheng
authors.forename: Borge
authors.initials: B
authors.lastname: Ten Hagen
authors.forename: Andreas
authors.initials: A
authors.lastname: Kaiser
authors.forename: Meiling
authors.initials: M
authors.lastname: Wu
authors.forename: Haihang
authors.initials: H
authors.lastname: Cui
authors.forename: Zhanhua
authors.initials: Z
authors.lastname: Silber-Li
authors.forename: Hartmut
authors.initials: H
authors.lastname: Löwen