We report numerical and experimental results indicating successful stabilization of unstable steady states and periodic orbits in an electrochemical system. Applying a continuous delayed-feedback technique not only periodic and chaotic oscillations are suppressed via stabilization of steady-state solutions but also the chaotic dynamics can be converted to periodic behavior. In all cases the feedback perturbation vanishes as a target state is attained.

Model calculations indicate that chaotic current oscillations during anodic electrodissolution of copper into phosphoric acid may be controlled by applying a simple map-based algorithm. In the experiments, the unstable period-one and period-two orbits embedded in the chaotic attractor have been stabilized by small perturbations of the anodic potential. We present the results of an experimental test for a power law relating the average chaotic transient time to the size of maximum perturbation allowed during control. The reported experimental results are in good agreement with the theoretical predictions by Ott, Grebogi, and Yorke.

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We report the synchronization of two spatially extended chemical systems. In one spatial dimension, under appropriate parameter conditions, the model systems exhibit a transition to turbulence via backfiring of pulses. By implementing continuous control to the underlying partial differential equations synchronization is achieved not only for identical systems, but also for systems operating under unequal parameter values exhibiting different dynamical behavior. Using this technique, spatiotemporal chaos ͑turbulence͒ can be suppressed, maintained, or even enhanced depending on the dynamical behavior of the drive system. This could possibly be of relevance to biological systems, where in certain situations the emergence of chaos is undesirable while under different circumstances the loss of the chaotic dynamics is undesirable ͑epileptic seizures͒.

We report experimental evidence of explosive synchronization in coupled chemo-mechanical systems, namely in mercury beating-heart (MBH) oscillators. Connecting four MBH oscillators in a star network configuration and setting natural frequencies of each oscillator in proportion to the number of its links, a gradual increase of the coupling strength results in an abrupt and irreversible (first-order-like) transition from the system's unordered to ordered phase. On its turn, such a transition indicates the emergence of a bistable regime wherein coexisting states can be experimentally revealed. Finally, we prove how such a regime allows an experimental implementation of magneticlike states of synchronization, by the use of an external signal.