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arXiv · 1702.08020

Self-assembly of colloidal molecules due to self-generated flow

Ran Niu·Thomas Speck·Thomas Palberg
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Abstract

The emergence of structure through aggregation is a fascinating topic and of both fundamental and practical interest. Here we demonstrate that self-generated solvent flow can be used to generate long-range attractions on the colloidal scale, with sub-pico Newton forces extending into the millimeter-range. We observe a rich dynamic behavior with the formation and fusion of small clusters resembling molecules, the dynamics of which is governed by an effective conservative energy that decays as $1/r$. Breaking the flow symmetry, these clusters can be made active.

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Ran Niu, Thomas Speck, Thomas Palberg. 2017-02-26. Self-assembly of colloidal molecules due to self-generated flow. https://doi.org/10.1103/physrevlett.119.028001

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