Computational methods for modelling multiply-charged droplets
Charged materials in alternating electric fieldRobert Holyst
University of Warsaw, Poland
Charged materials are always electrically neutral and strong, long range Coulomb interactions are screened by ions. Electric field of low frequency moves these ions and separates plus and minus charges for a short period of time. These ions can shift boundaries between materials of different conductivity. The strongest effects are observed for such frequencies of the field that makes the ions travel a distance of the size of the Debye length in one period of the electric field. I will show a number of experiments performed on such systems. They are as follows: a freely suspended polar/ferroelectric liquid crystals, mixtures of polymers and liquid crystals undergoing phase separation, microfluidic system of water droplets immersed in oil and finally water between plates, at hundreds of nanometer separation, in the surface force apparatus.
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