Nonlinear Optical Properties of Ag-Sb2Se3 Nanofilm in the Near-Infrared Region

Sb2Se3 is an emerging material in recent years, and previous studies have shown that it exhibits excellent optoelectronic properties when doped with metals. In this experiment, magnetron sputtering technology was also used to prepare Ag-Sb2Se3 doped nano thin films using a dual target co sputtering method. The sputtering power of the RF target was set to 50 W, and the sputtering power of the DC target was 1 W, 2 W, and 3 W, respectively. The nonlinear optical properties of the sample film were studied using femtosecond Z-scan technology at 800 nm. The results indicate that both pure Sb2Se3 and doped Sb2Se3 thin films exhibit reverse saturation absorption (RSA). The reverse saturation absorption of doped Sb2Se3 thin films is mainly due to the presence of two-photon absorption (TPA), free carrier absorption (FCA), and defect energy levels. Compared with pure Sb2Se3 thin films, Ag-Sb2Se3 thin films exhibit significantly enhanced nonlinear absorption and nonlinear refractive properties. The nonlinear optical properties of Ag-Sb2Se3 thin films were improved by increasing the Ag sputtering power and incident laser energy. The thin film was characterized by SEM, XRD, UV-Vis and other testing methods, and it was found that the doping of metal Ag greatly improved and optimized the stacking properties of the film, and adjusted the optical bandgap of the film. The better properties of metal-Sb-Se3 nanomembranes were further explored.