Self-Organized Patterns of Micrometer sized Particles in Electric Fields


A surprisingly diverse set of interesting patterns formed by colloidal particles are discovered in the vertical DC electric field. The patterns are made of many different static or quasi-stationary dynamic structures and located in the bulk or on the electrodes. It is a coupled system of hydrodynamics and reaction-diffusion of ions and colloidal particles in the electric field.

vertical DC field, microscopic patterns

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Quasi-stationary dynamic structures such as flowers, toroids, labyrinth, islands, blobs, smoke-rings etc.
movie

vertical DC field, macroscopic patterns

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double-rolls, labyrinth, honeycomb etc.

(electric analogy of Raleigh-Benard convections)


vertical DC field, transient surface patterns

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horizontal AC field (discovered before)

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straight bands, zigzag bands, chains etc.