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Surmounting Barriers: The Benefit of Hydrodynamic Interactions

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 Added by Holger Stark
 Publication date 2005
  fields Physics
and research's language is English




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We experimentally and theoretically investigate the collective behavior of three colloidal particles that are driven by a constant force along a toroidal trap. Due to hydrodynamic interactions, a characteristic limit cycle is observed. When we additionally apply a periodic sawtooth potential, we find a novel caterpillar-like motional sequence that is dominated by hydrodynamic interactions and promotes the surmounting of potential barriers by the particles.



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