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

P5.78Wed 711:10-14:00Dynamic behavior of ferrofluids in time-dependent fieldsSebastian Jäger 1 and Sabine H. L. Klapp 11 Technische Universität Berlin, Hardenbergstr. 36, 10623, Berlin, GermanyWe investigate suspensions of colloidal dipolar particles that are exposed to external timedependentfields. Mainly, we are interested in the dynamic behavior and structure formation phenomenathat the colloidal particles exhibit under the influence of rotating external fields. Here weinvestigate synchronization as well as desynchronization effects of the particles with the externalfield and how these effects can result in the formation of layers. We also discuss the structure ofthe particles within those layers and the onset and breakdown of layer formation for an alreadysynchronized state [1]. We do this by employing computer simulations, most notably Brownian(Langevin) dynamics simulations, that are supplemented by analytical considerations. In particular,we propose a simple theory that describes the formation of layers in a density functionalframework.[1] S. Jäger and S. H. L. Klapp, accepted at Soft Matter.78