Nonlinear optical properties of Ag/PMMA nanocomposite polymer film

We prepared Ag/PMMA nanocomposite polymer film by a simple in situ synthesis and measured their linear and nonlinear optical properties to evaluate their potential applications to all-optical devices. The linear absorption spectrum has shown the increase of absorption intensity in the presence of Ag nanoparticles. Nonlinear optical properties were studied using Z-scan technique with 13 ns pulse duration at 532 nm. The nonlinear refractive index gamma and nonlinear absorption coefficient beta of Ag/PMMA nanocomposite polymer film were measured to be 5.781 x 10^-2 cm² GW and 2.225 x 10³ cm I GW , respectively. Giant enhancement of nonlinear optical responses was found for Ag/PMMA nanocomposite polymer film compared with pure PMMA (Polymethyl Methacrylate) film. The results indicate that the enhancements of linear and nonlinear optical properties were caused by the surface plasmon resonance of Ag nanoparticles. Analyzed with respect to Stegeman figures of merit, the Ag/PMMA nonlinear polymer film show promise for practical use in ultrafast optical devices.