Abstract

The question of stochasticity versus deterministic chaos is an outstanding issue in the field of nonlinear dynamics. In optics this has recently been a focus of attention in regard to stimulated Brillouin scattering (SBS).¹ While the temporal structure of basic SBS has been found experimentally to be dominantly stochastic due to noise resulting from the spontaneous thermal fluctuation,^2,3 theory predicts that in the absence of the latter the SBS exhibits dynamical instabilities and chaos.⁴ To date such deterministic dynamical features have been experimentally observed in SBS with feedback,¹ the latter seemingly acting to suppress stochasticity in the emission. However, such underlying deterministic behaviour is most readily interrogated in amplifier configuration in which effects of noise interaction can be eliminated. The significant findings in our analysis of such a systems how that over broad range of operating conditions the amplified signal exhibits deterministic chaos and instabilities as a consequence of the effects of nonlinear refraction and detuning. Without nonlinear refraction the amplified signal of the cw SBS seed is dominantly stochastic and cw amplification only occurs over a narrow range around the gain center.

© 1994 IEEE