Dark pulses, defined as localized intensity dips on a stable continuous-wave (CW) background, represent a unique class of optical solitons. Their immunity to interference, among other characteristics, makes them promising for optical communication and sensing. Following a period of limited progress after their initial demonstration, research on dark pulses has surged in the past decade, driven by the emergence of novel materials and innovative light control techniques. This review examines various techniques employed to achieve stable dark pulse generation, with particular emphasis on the role of novel real and artificial saturable absorbers (SAs) and their influence on dark pulse characteristics and overall laser performance. By synthesizing these findings, this review serves as a valuable resource for researchers investigating on dark pulse dynamics and the development of next-generation fiber laser systems.
Chen et al. (Tue,) studied this question.