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arXiv · 0706.4406

Self-motile colloidal particles: from directed propulsion to random walk

Jonathan R. Howse·Richard A. L. Jones·Anthony J. Ryan·Tim Gough·Reza Vafabakhsh·Ramin Golestanian
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Abstract

The motion of an artificial micro-scale swimmer that uses a chemical reaction catalyzed on its own surface to achieve autonomous propulsion is fully characterized experimentally. It is shown that at short times, it has a substantial component of directed motion, with a velocity that depends on the concentration of fuel molecules. At longer times, the motion reverts to a random walk with a substantially enhanced diffusion coefficient. Our results suggest strategies for designing artificial chemotactic systems.

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Jonathan R. Howse, Richard A. L. Jones, Anthony J. Ryan, Tim Gough, Reza Vafabakhsh, Ramin Golestanian. 2007-06-29. Self-motile colloidal particles: from directed propulsion to random walk. https://doi.org/10.1103/physrevlett.99.048102

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