Optical properties of Ag nanocrystals in Sc and O sequentially implanted silica

The implantation of Sc and O results in the modification of the silica with polarizable Sc3+ ions. During annealing the Sc ions are incorporated with the O in the network to form a Sc–O–silicate layer. Subsequent implantation of Ag into this layer results in the formation of Ag metal nanocrystals with significantly modified optical properties compared to samples without the Sc ions. The size distribution of the Ag nanocrystals narrowed with increasing Sc concentration, due to the gradual elimination of a band of large Ag clusters. The incorporation of the Sc results in a shift in the wavelength of the surface plasmon resonance of the Ag nanocrystals and a change in the magnitude of the surface plasmon resonance absorption. The results are interpreted using effective medium theory.