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arXiv · 1706.02067

Dynamical design of spatial patterns of colloidal suspensions

N. A. M. Araujo·D. A. Zezyulin·V. V. Konotop·M. M. Telo da Gama
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Abstract

We study the collective dynamics of colloidal suspensions in the presence of a time-dependent potential, by means of dynamical density functional theory. We consider a non-linear diffusion equation for the density and show that spatial patterns emerge from a sinusoidal external potential with a time-dependent wavelength. These patterns are characterized by a sinusoidal density with the average wavelength and a Bessel-function envelope with an induced wavelength that depends only on the amplitude of the temporal oscillations. As a generalization of this result, we propose a design strategy to obtain a family of spatial patterns using time-dependent potentials of practically arbitrary shape.

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N. A. M. Araujo, D. A. Zezyulin, V. V. Konotop, M. M. Telo da Gama. 2017-06-07. Dynamical design of spatial patterns of colloidal suspensions. https://arxiv.org/abs/1706.02067

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