Stable operation of a passive fiber resonator in the bistable and period-doubling regimes

Abstract

Synchronously driven passive fiber resonators constitute a class of devices of growing interest from both fundamental and applied points of view. They can be found in practice as the basic elements of a large number of fiber-based devices such as APM lasers, fiber Raman lasers or fiber loop memories. From a more fundamental point of view, a passive nonlinear fiber resonator is structurally so simple and such a broad spectrum of complex behaviors that it is considered as the paradigm of an optical system prone to instabilities and chaos. A first experimental attempt was made to explore the chaotic dynamics of passive fiber resonators in 1983 [1]. The resonator was driven synchronously with Q-switched picosecond laser pulse trains in order to reach the power levels required for sufficient nonlinearity and the onset of chaos. Because of the lack of control of the driving field and of the cavity phase shift (i.e., cavity round-trip phase change), a clean demonstration of chaos and comparison with theory were proved to be much harder to do than originally anticipated. Since then, other authors have attempted to do better using cw mode-locked lasers [2-4]. In refs. 3 and 4 a measure of the cavity phase shift is made which allows for meaningful comparison with theory. However, no direct control of the cavity phase shift is performed in these experiments. As a result, the cavity phase shift fluctuates which makes difficult a systematic study of the complex dynamical behaviors and their potential applications.