Stochastic resonance and noise-enhanced order with spatiotemporal periodic signal

Stochastic resonance is investigated in a chain of coupled threshold elements driven by independent noises and a plane traveling wave. Both stochastic resonance in an individual element embedded in the chain, characterized by a maximum of the signal-to-noise ratio for nonzero noise intensity, and stochastic resonance with spatiotemporal signal, characterized by a maximum of the spatiotemporal input-output correlation function, are observed. For a wide range of wavelengths of the plane wave an optimum value of coupling exists for which both kinds of stochastic resonance are most pronounced, i.e., the phenomenon of array enhanced stochastic resonance is observed. For large wavelengths the enhancement of stochastic resonance coincides with a maximum of spatiotemporal synchronization among elements with the same phase of the periodic signal at inputs. This synchronization is a manifestation of spatiotemporal order induced in the system by the cooperative influence of noise and periodic signal.