Noise-induced remote synchronization in star networks

Remote synchronization (RS) refers to coherence among peripheral nodes that are indirectly connected and remain desynchronized from their common hub. While RS has been extensively studied in deterministic systems, the role of stochastic perturbations in enabling or enhancing RS remains poorly understood. Here, we show that noise can induce RS in star-structured networks of coupled Stuart–Landau oscillators. As the noise intensity increases, the system exhibits four distinct dynamical regimes: a disordered state, noise-induced remote synchronization (NRS), phase-only noise-induced remote synchronization (PNRS), and noise-induced death. These regimes are distinguished by their phase coherence, frequency synchronization properties, and noise-driven spectral characteristics. A phase diagram in the coupling-noise parameter space reveals that NRS typically arises near the intrinsic RS boundary, where noise selectively enhances coordination through topology-dependent resonance filtering. A linearized frequency-domain analysis supports the numerical findings, providing a mechanistic explanation of how stochastic inputs can facilitate long-range synchronization. These results reveal a constructive role of noise in generating RS and uncover a new class of noise-induced dynamical states in complex networks.