Plasmonics is the most promising field appointed to continue the predictions of the Law of Moore as well as for the confinement of light on a subwavelength spatial scale, allowing the breaking of the diffraction limit. In that direction, we have produced by ion implantation, interesting nanocomposites with very attractive optical properties. Recently, a double implantation of Si and Ag ions in silica, with subsequent thermal treatments in appropriated atmospheres, allowed us to obtain two layers: one of Si nanocristals (NCs), and other of Ag nanoparticles (NPs). This arrangement shows an enhancement of the emission of Si nanocrystals (NCs) in a new, totally integrated configuration. The synthesis of the system by ion implantation offers a total protection of the optical active agents from environmental effects such as oxidation, additionally assuring a high degree of homogeneity. We present a photoluminescence excitation study (420-500 nm) of Si NCs, with and without the presence of Ag nanoparticles (NPs), both embedded in a matrix of SiO₂. The level of saturation for Si NCs is independent of the excitation wavelength, but for Si NCs in the presence of Ag NPs, a saturation level arises for excitation wavelengths near the absorption band of the surface plasmon resonance of the Ag NP (325-475 nm). The increase of both, the values of saturation and excitation cross-section of Si NCs in the presence of Ag NPs, is an evidence of the optical interaction between the metal NPs and Si NCs studied in this work. This suggests a decrease of the lifetime of Si NCs photoemission due to the interaction with the Ag NPs.

Date Published: 25 October 2011
PDF: 6 pages
Proc. SPIE 8011, 22nd Congress of the International Commission for Optics: Light for the Development of the World, 80113D (25 October 2011); doi: 10.1117/12.901992

Published in SPIE Proceedings Vol. 8011:
22nd Congress of the International Commission for Optics: Light for the Development of the World
Ramón Rodríguez-Vera; Ramón Rodríguez-Vera; Ramón Rodríguez-Vera; Rufino Díaz-Uribe; Rufino Díaz-Uribe; Rufino Díaz-Uribe, Editor(s)