Regensburg 2019 – wissenschaftliches Programm
DY 20.1: Vortrag
Dienstag, 2. April 2019, 14:00–14:15, H3
Collective behavior of active colloids in confined viscoelastic fluids — •N Narinder1, Mahsa Sahebdivani1, Juan Ruben Gomez-Solano2, and Clemens Bechinger1 — 1Fachbereich Physik, Universität Konstanz, Konstanz, Germany — 2Instituto de Física, Universidad Nacional Autónoma de México, México.
The natural habitat of microorganisms is complex not only in geometrical aspects but also in the sense that it is viscoelastic . The fundamental question to address is what prime role such sophisticated surroundings play. To uncover this, we experimentally study the motion of light activated Janus particles in a viscoelastic fluid inside hard wall circular confinements. Unlike a Newtonian liquid , we observe that particles in viscoelastic fluids  experience an elastic repulsion from the walls which strongly depends on their activity and the elasticity of the surrounding fluid. Furthermore, strongly confined many-particle system inside circular pores exhibits a transition from liquid-like to a well-organized crystal-like behavior upon increasing the activity of particles. A further increase in activity liquifies the system and thus a reentrant liquid-like behavior is observed.
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