Breakdown of stochastic resonance in complex networks

TL;DR

This paper investigates how local defects in oscillator resonance abilities can disrupt stochastic resonance in complex networks, highlighting the roles of network topology, coupling, and noise levels in this phenomenon.

Contribution

It introduces a study of the impact of nonresonant oscillators on stochastic resonance in complex networks, supported by a low-dimensional deterministic model.

Findings

Nonlinear relationship between nonresonant oscillators and their dissimilarity

Network topology influences stochastic resonance stability

Coupling strength and noise levels affect resonance maintenance

Abstract

In networked systems, stochastic resonance occurs as a collective phenomenon where the entire stochastic network resonates with a weak applied periodic signal. Beyond the interplay among the network coupling, the amplitude of the external periodic signal, and the intensity of stochastic fluctuations, the maintenance of stochastic resonance also crucially depends on the resonance capacity of each oscillator composing the network. This scenario raises the question: Can local defects in the ability of oscillators to resonate break down the stochastic resonance phenomenon in the entire network? Here, we investigate this possibility in complex networks of prototypical bistable oscillators in a double-well potential. We test the sustainability of stochastic resonance by considering a fraction of network oscillators with nonresonant potential landscapes. We find that the number of nonresonant oscillators depends nonlinearly on their dissimilarity from the rest of the network oscillators. In addition, we unravel the role of the network topology and coupling strength in maintaining, or suppressing, the stochastic resonance for different noise levels and number of nonresonant oscillators. Finally, we obtain a low-dimensional deterministic model confirming the results observed for the networks.