Wavelength-Dependent Nonlinear Optical Properties of Ag Nanoparticles Dispersed in a Glass Host

Abstract

The linear and nonlinear optical properties of metal nanoparticles are highly tunable by variation of parameters such as particle size, shape, composition, and environment. To fully exploit this tunability, however, quantitative information on nonlinear absorption cross sections is required, as well as a sufficient understanding of the physical mechanism underlying these nonlinearities. In this work, we present a detailed and systematic investigation of the wavelength-dependent nonlinear optical properties of Ag nanoparticles embedded in a glass host, in which the most important parameters determining the nonlinear behavior of the system are characterized. This allows a proper quantification of absorption cross sections and elucidation of the excitation mechanism. Based on small-angle X-ray scattering measurements average particle diameters of 3 and 17 nm are estimated for the studied samples. The nonlinear optical properties of the nanoparticle–glass composite are studied in an extended wavelength range ...