Slip, ypsotaxis, and synchronization of catalytically self-propelled particles.
By: Daniela Kraft
From: U. Leiden, The Netherlands
At: Online - Zoom (https://videoconf-colibri.zoom.us/j/84749978538)
[2021-04-29]
Synthetic microswimmers constitute a new class of nonequilibrium model systems that hold great promise for applications and understanding the behavior of biological microswimmers. A simple experimental realization of such microswimmers are spheres half coated with platinum, that propel themselves autonomously in the presence of hydrogen peroxide. These synthetic swimmers have a strong affinity for surfaces, but little is known about how surfaces affect their behavior. In this talk, I will demonstrate that the choice of the substrate material has a strong influence on the microswimmer speed through slippage [1]. Using a new height analysis approach, I will show that the microswimmer-wall separation is surprisingly robust for a range of salt concentrations, swimmer surface charges, and swimmer sizes [2]. Confining multiple swimmers further to one-dimensional environments, we find complex cooperative behavior such as a collective speed up and dynamic chain-formation and disassembly. [3] Finally, I will discuss the implications of these striking, activity-induced behaviors for the still-debated propulsion mechanism.
