Ultrafast Laser Pulses Generation by Using 2D Layered PtS2 as a Saturable Absorber

Platinum disulfide (PtS 2 ) has recently drawn extensive research interest due to its excellent electronic properties, controllable bandgap over a broad range, and high air stability. Herein, we demonstrate the generation of mode-locked ultrafast laser pulses by using PtS 2 nanosheets for the first time, which were fabricated by ultrasonic exfoliation followed by the centrifugation process. The fabricated PtS 2 saturable absorber (SA) was used within two different fiber laser systems. Ultrafast laser pulses with pulse duration of 2.1 ps, 3-db bandwidth of 2.5 nm, and repetition rate of 15.04 MHz were produced from an Er-doped fiber laser system with an operational wavelength of 1.572 μm. Additionally, a mode-locking pulse train with repetition rate of 11.2 MHz was obtained by using the fabricated PtS 2 SA within Yb-doped fiber laser system with operational wavelength of ∼1 μm. It is expected that these results will trigger further research with wide potential applications of PtS 2 in the field of nonlinear optics and ultrafast photonics.