Stochastic and coherence resonance in lasers: homoclinic chaos and polarization bistability
نویسندگان
چکیده
We report Stochastic Resonance and Coherence Resonance phenomena in experiments using CO2 lasers. First, we consider a polarized laser with feedback; for suitable feedback parameters, the laser intensity undergoes homoclinic chaos consisting in the return to a saddle focus, where noise controls the permanence time around the saddle. Second, we discuss a quasi-isotropic laser where noise induces switching between two intensity components with mutually orthogonal polarization. PACS. 05.40.Ca Noise – 42.60.Mi Dynamical laser instabilities; noisy laser behavior – 42.65.Sf Dynamics of nonlinear optical systems; optical instabilities, optical chaos and complexity, and optical spatio-temporal
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