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arXiv · 1907.06813

Hydrodynamic synchronization and collective dynamics of colloidal particles driven along a circular path

Takumi Miyamoto·Masayuki Imai·Nariya Uchida
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Abstract

We study theoretically the collective dynamics of particles driven by an optical vortex along a circular path. Phase equations of N particles are derived by taking into account both hydrodynamic and repulsive interactions between them. For N = 2, the particles attract with each other and synchronize, forming a doublet that moves faster than a singlet. For N = 3 and 5, we find periodic rearrangement of doublets and a singlet. For N = 4 and 6, the system exhibits either a periodic oscillating state or a stable synchronized state depending on the initial conditions. These results reproduce main features of previous experimental findings. We quantitatively discuss the mechanisms governing the non-trivial collective dynamics.

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Takumi Miyamoto, Masayuki Imai, Nariya Uchida. 2019-09-27. Hydrodynamic synchronization and collective dynamics of colloidal particles driven along a circular path. https://doi.org/10.1103/physreve.100.032607

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