Can Stochastic Resonance Lead to Order in Chaos?

Abstract

The dynamical behavior of two coupled chaotic oscillators was experimentally studied under superposition of both noise and periodic external forces. Increasing the noise intensity the chaotic behavior was suppressed and the signal-to-noise ratio (SNR) became maximum at a certain noise intensity; that is, the stochastic resonance phenomenon was observed. In order to define the states more quantitatively and compare to the change of SNR the largest Lyapunov exponent was calculated which showed a drastic change from a positive value in the chaotic state to zero in the resonance regimes; noise-induced order was observed.