Comprehensive study on the nonlinear optical properties of Ag/MoSe2 composite films

MoSe2 thin films and Ag/MoSe2 composite thin films were prepared by physical vapour deposition (PVD). The morphology and structure of the composite film were characterized by scanning electron microscopy and absorption spectroscopy. The UV-visible absorption spectrum characterizes the linear absorptivity of the composite films. Due to the plasma effect of Ag nanofilms, the Ag/MoSe2 composite films showed a significant increase in the absorption intensity of the films compared to the MoSe2 films. The nonlinear absorption properties of MoSe2 thin films were investigated using the open-aperture Z-scan technique. The calculated nonlinear absorption coefficient (β) showed that the nonlinear absorption coefficient of the Ag/MoSe2 composite film is an order of magnitude higher than that of the MoSe2 film, indicating that the Ag nanofilm can better improve the nonlinear absorption properties of the MoSe2 film.