How to capture active particles

A. Kaiser; H. H. Wensink; H. Löwen

doi:10.1103/physrevlett.108.268307

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arXiv · 1202.0312

How to capture active particles

A. Kaiser·H. H. Wensink·H. Löwen

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Abstract

For many applications, it is important to catch collections of autonomously navigating microbes and man-made microswimmers in a controlled way. Here we propose an efficient trap to collectively capture self-propelled colloidal rods. By means of computer simulation in two dimensions, we show that a static chevron-shaped wall represents an optimal boundary for a trapping device. Its catching efficiency can be tuned by varying the opening angle of the trap. For increasing angles, there is a sequence of three emergent states corresponding to partial, complete, and no trapping. A trapping `phase diagram' maps out the trap conditions under which the capture of self-propelled particles at a given density is rendered optimal.

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A. Kaiser, H. H. Wensink, H. Löwen. 2012-02-01. How to capture active particles. https://doi.org/10.1103/physrevlett.108.268307

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