Passively Q-Switched and Mode-Locked Fiber Laser Based on a Zeolitic Imidazolate Framework-67 Saturable Absorber

Exploring new saturable absorber (SA) materials with excellent performance to achieve Q-switching and mode-locking operations is a hot topic in ultrafast laser research. The impressive specific surface areas, structural tunability, and high thermal and chemical stability of the zeolitic imidazolate framework (ZIF) materials make them promising candidates as high-performance SAs. In this work, we demonstrated the potential of the ZIF-67 SAs for ultrafast fiber laser applications. The nonlinear optical absorption characteristics of the ZIF-67 SAs at the telecommunication band were investigated by using the balanced twin-detector method. By incorporating the ZIF-67 SAs into the Er3+-doped fiber laser cavity, stable Q-switching and mode-locking operations were achieved. The research results are essential for promoting the application of novel hybrid nanomaterials in ultrafast lasers.