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arXiv · 1411.6847

Swimming in a Crystal:

Aidan T. Brown·Ioana D. Vladescu·Angela Dawson·Teun Vissers·Jana Schwarz-Linek·Juho S. Lintuvuori·Wilson C. K. Poon
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Abstract

We study catalytic Janus swimmers and Escherichia coli bacteria swimming in a two-dimensional colloidal crystal. The Janus swimmers orbit individual colloids and hop between colloids stochastically, with a hopping rate that varies inversely with fuel (hydrogen peroxide) concentration. At high fuel concentration, these orbits are stable for 100s of revolutions, and the orbital speed oscillates periodically as a result of hydrodynamic, and possibly also phoretic, interactions between the swimmer and the six neighbouring colloids. Motile E.~coli bacteria behave very differently in the same colloidal crystal: their circular orbits on plain glass are rectified into long, straight runs, because the bacteria are unable to turn corners inside the crystal.

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Aidan T. Brown, Ioana D. Vladescu, Angela Dawson, Teun Vissers, Jana Schwarz-Linek, Juho S. Lintuvuori, Wilson C. K. Poon. 2014-11-25. Swimming in a Crystal:. https://arxiv.org/abs/1411.6847

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