Crisis and stochastic resonance in Shinriki’s circuit

In nonlinear electronic oscillators of the Chua type the merging of two precritical attractors leads to crisis-induced chaos–chaos intermittency. This behavior can be induced either by addition of noise to the precritical system or by variation of a control parameter. Close to such a crisis small periodic signals can be enhanced by the addition of noise via the mechanism of stochastic resonance. We present an experimental observation of this effect as well as a thorough description of the critical behavior of the system.