Experimental and Theoretical Study of Forced Synchronization of Self-Oscillations in Liquid Ferrocolloid Membranes

A ferrocolloid is a suspension of nanometer-sized ferromagnetic particles (magnetite) in a carrier liquid (kerosene). A unique feature of a ferrocolloid is the fact that layers consisting of densely packed particles are formed near the electrode surface under the influence of an external electric field. Each layer is a liquid membrane, and its formation significantly affects the various properties of the system. For example, the development of a unique phenomenon in a ferrocolloid is self-organization (self-oscillations and autowaves). The applied external periodic force leads to a change (capture) of the frequency of the autowave process-forced synchronization of autowaves. The experimentally obtained synchronization was investigated by the method of electrically controlled interference. After multiple experiments and theoretical studies, a physical mechanism for the synchronization of the autowave process in a cell with a ferrocolloid was proposed for the first time. A mathematical model of forced synchronization of autowaves, which is described by a system of nonlinear differential equations, was proposed for the first time as well. Adding an external periodic force into the model led to a change in the frequency of autowaves; synchronization by an external force was confirmed by computational experiments.