Nanostructured MoWTe ₂ as a Saturable Absorber for Near-Infrared Ultrafast Fiber Lasers

As a prominent member of the transition metal dichalcogenides (TMDs), MoWTe 2 exhibits unique optoelectronic properties in the near-infrared (NIR) range and broad application prospects. In this study, we fabricated a MoWTe 2 saturable absorber (SA) from ultrathin nanosheets (∼1.5 nm) with distinctive nanoscale features. We integrated this SA into an erbium-doped fiber laser (EDFL) system. Leveraging its superior nonlinear optical response, we achieved stable fundamental mode locking (FML), Q-switched mode locking (QML), and dissipative soliton resonance (DSR) outputs. This work demonstrates, for the first time, the modulation capability of MoWTe 2 for QML and DSR. These results highlight its adaptability to diverse pulse regimes. Overall, this study lays a foundation for MoWTe 2 applications in the NIR range and provides critical material support for high-performance nonlinear laser devices.