Stochastic Resonance in Chaotic Spin-Wave Dynamics

We report the first experimental observation of noise-free stochastic resonance by utilizing the intrinsic chaotic dynamics of the system. To this end we have investigated the effect of an external periodic modulation on intermittent signals observed by high power ferromagnetic resonance in yttrium iron garnet spheres. Both the signal-to-noise ratio and the residence time distributions show the characteristic features of stochastic resonance. The phenomena can be explained by means of a one-dimensional intermittent map. We present analytical results as well as computer simulations.