Noise effects on excitable chaotic attractors in coupled light-emitting diodes

Recent studies demonstrated that chaotic spike sequences appearing in the context of incomplete homoclinic scenarios can be understood in terms of excitability of chaotic attractors. So far, this particular dynamic has been found in a semiconductor laser with optoelectronic feedback. Here, we show that the same phenomenology occurs also in light-emitting diodes, which are ideal candidates for the implementation of a complex network on a chip. In particular, we study the appearance of both stochastic incoherence (SI) and stochastic coherence (SC) in a single unit, as well as in two coupled units. We demonstrate experimentally and explore numerically the enhancement of SC and worsening of SI induced by coupling systems in array.