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arXiv · 1704.07533

Distinguishing Advective and Powered Motion in Self-Propelled Colloids

Young-Moo Byun·Paul E. Lammert·Yiying Hong·Ayusman Sen·Vincent H. Crespi
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Abstract

Self-powered motion in catalytic colloidal particles provides a compelling example of active matter, i.e. systems that engage in single-particle and collective behavior far from equilibrium. The long-time, long-distance behavior of such systems is of particular interest, since it connects their individual micro-scale behavior to macro-scale phenomena. In such analyses, it is important to distinguish motion due to subtle advective effects -- which also has long time scales and length scales -- from phenomena that derive from intrinsically powered motion. Here, we develop a methodology to analyze the statistical properties of the translational and rotational motions of powered colloids to distinguish, for example, active chemotaxis from passive advection by bulk flow.

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Young-Moo Byun, Paul E. Lammert, Yiying Hong, Ayusman Sen, Vincent H. Crespi. 2017-09-17. Distinguishing Advective and Powered Motion in Self-Propelled Colloids. https://doi.org/10.1088/1361-648x%2Faa88f1

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