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

      Gough, Timothy D.; Howse, J.R.; Jones, R.A.L.; Ryan, A.J. (2009-07-27)
      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.