Thermal self-stability, multi-stability, and memory effects in single-mode Brillouin fiber lasers

The main drawback of fiber lasers is their high sensitivity to fluctuation in the properties of their surroundings, where even a minuscule fluctuation in the ambient parameters can destabilize them. In this paper, a new passive feedback mechanism inherent to Brillouin fiber lasers (BFLs) is presented and studied. This mechanism, stemming from the interplay between thermal optical-length variations and the gain-line induced frequency dependent lasing power, triggers unexpected and counter-intuitive phenomena such as self-frequency-stabilization, multi-stability, and memory effects. This feedback sheds light on the dynamic behavior of BFLs and can be controlled and modified by engineered the gain lineshape.