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

As a prominent member of the transition metal dichalcogenides (TMDs), MoWTe2 exhibits unique optoelectronic properties in the near-infrared (NIR) range and broad application prospects. In this study, we fabricated a MoWTe2 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 MoWTe2 for QML and DSR. These results highlight its adaptability to diverse pulse regimes. Overall, this study lays a foundation for MoWTe2 applications in the NIR range and provides critical material support for high-performance nonlinear laser devices.