Recent Advances in MoS₂-Based Saturable Absorbers for Mode-Locked Fiber Lasers

Ultrashort pulse mode-locked fiber lasers demonstrate significant application potential in optical communication, precision measurement, and ultrafast photonics. As the critical component for pulse generation, the performance of saturable absorbers directly dictates the output characteristics of these lasers. To address the limitations of traditional saturable absorbers regarding operating bandwidth, fabrication cost, and environmental stability, two-dimensional transition metal dichalcogenides represented by molybdenum disulfide have emerged as research hotspots in the field of novel saturable absorbers due to their broadband tunability, superior nonlinear optical response, and flexible fabrication processes. This review focuses on molybdenum disulfide saturable absorbers and systematically summarizes their nonlinear optical properties, mainstream fabrication strategies, and recent application progress in mode-locked fiber lasers. Furthermore, the advantages and challenges concerning key performance metrics such as pulse stability, output power, and pulse duration are comprehensively evaluated. Finally, future perspectives on critical issues including fabrication process optimization, long-term stability enhancement, and composite structure design are discussed. This work aims to provide theoretical references and technical support for the practical application of high-performance ultrashort pulse fiber lasers.