Stochastic resonance and noise-enhanced order with spatiotemporal periodicsignal

Stochastic resonance is investigated in a chain of coupled threshold elemen ts 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 st ochastic resonance with spatiotemporal signal, characterized by a maximum o f the spatiotemporal input-output correlation function, are observed. For a wide range of wavelengths of the plane wave an optimum value of coupling e xists for which both kinds of stochastic resonance are most pronounced, i.e ., the phenomenon of array enhanced stochastic resonance is observed. For l arge wavelengths the enhancement of stochastic resonance coincides with a m aximum 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.