Stochastic resonance in coupled threshold elements on a Barabási–Albert network

Stochastic resonance is investigated in a system of threshold elements located at nodes and coupled along edges of a Barabási–Albert network, driven by a common subthreshold periodic signal and independent noises. Array-enhanced stochastic resonance is observed, i.e., increase of the spectral power amplification evaluated from the mean output of the network due to proper coupling. This enhancement occurs though the response of individual threshold elements to the periodic signal is very diverse due to a power-law distribution of their connectivity. Numerical results are qualitatively explained using simple linear response theory in the mean field approximation.