The Quincke effect is an electrohydrodynamic phenomenon in which dielectric particles suspended in a weakly conductive liquid spontaneously begin to rotate when exposed to an external electric field. If the particles are in contact with a surface, this rotation results in rolling. We studied glass particles in a solution of the dioctyl sodium sulfosuccinate (AOT) in hexadecane, focusing on the dependence of the rolling velocity on the strength of the external electric field, as well as on the analysis of the oscillatory regime of the particles. For the purpose of the study, we established an experimental system with glass electrodes coated with indium tin oxide (ITO), which enabled the stable generation of a homogeneous electric field. The motion of several hundred particles was analyzed using optical microscopy and computer-based tracking, for different concentrations of AOT and at various electric field strengths. We compared the results with the existing model describing the dependence of the rolling velocity on the external electric field, as well as with the specific model we developed that takes into account the field-dependent conductivity of the medium. The experimental data showed a better fit to the specific model within the observed interval of electric field strengths. In addition to rolling, we systematically investigated the oscillatory regime of particle behavior. In this regime, the particles alternately move by approximately one particle diameter and then remain stationary for a certain time. We found that the average resting time decreases with increasing field strength, while the shape of the histogram of these time intervals also changes. Moreover, at electric field strengths below 2 MV/m, the maximum velocities of individual displacements often exceeded those of uniform rolling.
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