Abstract

The temporal behavior of stimulated Brillouin scattering (SBS) in an optical fiber under continuous-wave excitation is studied. In the absence of any feedback, the temporal evolution of the Stokes light for laser intensities well above SBS threshold is extremely noisy with nearly 100% fluctuations. The origin of these fluctuations is the spontaneous initiation of the SBS process. The experimental results agree with a theoretical analysis that includes the stochastic density fluctuations in the material. In the presence of a small amount of feedback, such as from the fiber endfaces, the Stokes light exhibits a transition to deterministic behavior in which the output either can be free of any fluctuations or can oscillate at harmonics of the round-trip time of the fiber.

© 1990 Optical Society of America