Ultrathin Ag and Ni/NiO films are sequentially produced on Corning glass and silicon substrates by means of magnetron sputtering. Post annealing treatment in a furnace with air at [Formula: see text]C and [Formula: see text]C may lead to the formation of Ag nanostructures in NiO environment. Some of these samples present local surface plasmon resonances (SPRs). The sequence in which each layer is deposited, as well as, the state of the structure on which the layer is deposited, appears to play a pivotal role in the optical properties of these nanostructures, which are attributed to the growth properties of the nanocomposite thin films. Ultimately, rigorous theoretical calculations have been made for comparison and discussion with the experimental results.

Plasmonic materials currently have a plethora of applications. How would a dielectric matrix, such as diblock copolymers, tune plasmonic properties? In this work, self-assembled gold nanoparticles were fabricated in medium vacuum conditions on heated Corning glass substrates (kept at 440 °C) under the coexistence of argon and air by means of DC magnetron sputtering. These samples were compared structurally and optically to samples deposited at room temperature and post annealed. Subsequently, the better of the two preparations, those deposited on heated glass, were covered with three different polymers, namely: Polystyrene-block-polybutadiene-block-polystyrene (PS-b-PBD-b-PS); Polystyrene-co-methyl methacrylate (PS-co-PMMA); and Polystyrene-block-polyisoprene-block-polystyrene (PS-b-PI-b-PS), by means of spin coating. Localized surface plasmon resonances were recorded and analyzed, respectively, for polymer-covered gold nanoparticles, with the width, intensity, and position of the resonances changing according to multiple factors, such as the nanoparticles size and the refractive index of each polymer. Lastly, for purposes of justification and comparison with the experimental results, rigorous theoretical calculations have been carried out.