Chaotic stimulated Brillouin scattering near the threshold in a fiber with feedback

We investigate a nonlinear dynamical behavior of the stimulated Brillouin scattering (SBS) near the threshold in the presence of feedback. When a cw Nd:YAG laser is injected into a single mode optical fiber, the SBS signal exhibits intermittently appearing irregular self-pulsations near the threshold. By examining the time series of the SBS signals, we verify that spontaneous Brillouin scattering having a stochastic property is dramatically suppressed due to the feedback. We explain the chaotic phenomenon of SBS in the presence of feedback in comparison with that in the absence of feedback.