Dresden 2017 – wissenschaftliches Programm
CPP 44.2: Vortrag
Mittwoch, 22. März 2017, 15:15–15:30, HÜL 186
Unexpected enhancement of rotational dynamics of self-propelled particles in a colloidal glass — •CELIA LOZANO1,2, JUAN RUBEN GOMEZ-SOLANO1, and CLEMENS BECHINGER1,2 — 12. Physikalisches Institut, Universitaet Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany — 2Max-Planck-Institute for Intelligent Systems, Heisenbergstrasse 3, 70569 Stuttgart, Germany
It has been recently demonstrated that the glass transition of dense colloidal suspensions is progressively shifted by increasing activity of embedded self-propelled particles (SPP) . However, it is not clear yet how the dynamics of such SPP becomes affected by the surrounding glassy environment. We experimentally investigate the active motion of spherical Janus particles within a cage created by a binary mixture of colloidal particles. We observe a dramatic enhancement of the rotational diffusion of active particles with increasing particle velocity and the density, in a similar fashion as SPP in semi-dilute polymer solutions . This experimental approach allows us to measure, in parallel, the temporal evolution of the active particle and the passive colloidal suspension. Our findings suggest that these effects originate from the coupling between the thermal fluctuations of the particle and the surrounding heterogeneities, which displays large relaxation times of several seconds.
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