Plasmon resonance and clustering of silver nanoclusters embedded in glass

Silver nanoclusters growth in AR Schott glass was investigated by transmission electron microscopy (TEM) and optical absorption. The studied samples were Ag-Na ion-exchanged and annealed at ambient air in a furnace. Optical absorption was performed to visualize the size effect on the spectra and compared to the Drude model. TEM was used to evaluate the distribution size of the silver particles so as to confirm the precipitation of the metallic nano-aggregates, to observe their morphological evolution with time, and to correlate it to the absorption curves which makes the interest and the aim of this study. The TEM observations prove that we are in a confinement regime with a particle size below the mean free path of the bulk metal. Growth of the clusters is ascribed first to the diffusion of the silver ions due to annealing and in a second time to an Oswald process.