Noise-sustained flashing structures in bistable systems

Fluctuations are an inherent feature of macroscopic systems. Rather than merely disturbing deterministic dynamics, noise can induce well-defined and often counterintuitive behaviors. We investigate noise-sustained flashing domain walls between stable states in convective bistable systems. By anchoring one end of the system in its least favorable stable state, noise persistently generates a pair of domain walls that propagate at different velocities, producing triangular patterns in the space–time diagram. Experimentally, this phenomenon is examined using a liquid crystal light valve with optical feedback, subjected to both fluctuating and controlled illumination. Theoretically, employing a bistable model with drift and noise, exhibiting noise-sustained flashing domain walls, we analyze the average emission time and size of these structures as functions of noise intensity, characterized by escape and relaxation times. The experimental observations align closely with the theoretical predictions.