8th Liquid Matter Conference September 6-10, 2011 Wien, Austria ...

Wed 711:10-14:00P5.53Particle dynamics in one- and two-dimensional randompotentialsFlorian Evers, 1 Richard Hanes, 1 and Stefan Egelhaaf 11 Heinrich-Heine-Universität Düsseldorf, Condensed Matter Physics Laboratory, 40225,Düsseldorf, GermanyWe experimentally studied the dynamics of individual colloidal particles in random potentials.Each local value of the one- or two-dimensional potentials was drawn from a Gaussian distribution,the width of which was varied between measurements. The random potentials were opticallygenerated [1] and the motion of the colloidal particles followed by video microscopy. The particledynamics have been studied over many orders of magnitude in time and characterised usingthe mean squared displacement, the van Hove function and the non-Gaussian parameter. Thedynamics are initially diffusive and then, at intermediate times, show an extended sub-diffusiveregime before diffusive motion is recovered at long times. The particle dynamics in the one- andtwo-dimensional potentials are quantitatively compared.[1] Hanes, R. D. L. , Jenkins, M. C. amp; Egelhaaf, S. U. , Rev. Sci. Instrum. 80, 083703(2009).53