TaS₂-based saturable absorbers for Q-switched fiber laser applications

Transition metal disulfides are widely applied as nonlinear optical materials for laser pulse generation. In this paper, TaS₂ is successfully used for the first time to achieve a high-energy passively Q-switched erbium-doped fiber (EDF) laser. TaS₂ nanosheets are prepared by the liquid phase exfoliation method, and then the TaS₂ solution is mixed with polyvinyl alcohol (PVA). TaS₂/PVA film is prepared, which is cut into 1 mm × 1 mm flakes. TaS₂/PVA saturable absorber (SA) is obtained by sandwiching a small flake between two fiber optic patch cable connectors. With the TaS₂/PVA SA added to an EDF laser, a Q-switched fiber laser with a center wavelength of 1560 nm and a repetition rate ranging from 51.33 kHz to 83.04 kHz is realized. At the pump power of 231 mW, the maximum output power is 1094 μW, and the shortest pulse duration is 3.48 μs. The results confirm that the TaS₂ material has excellent potential for application in nonlinear optics.