Ghost resonance in coupled lasers

We study the phenomenon of ghost resonance in a system of two bidirectionally coupled nonlinear oscillators. Ghost resonance was reported recently in an excitable system when perturbed by two periodic signals of different frequencies. Under these circumstances and with the help of noise, the system is able to resonate at a frequency not present in the external perturbations but related with them. In the current work, we give the first experimental evidence of ghost resonance in a coupled system which consists on two bidirectionally coupled semiconductor lasers.