title: Octahedral faceted Si nanoparticles as optical traps with enormous yield amplification.
abstract: We describe a method for the creation of an efficient optical scatter trap by using fully crystalline octahedral Silicon nanoparticles (Si-NPs) of approximately 100 nanometres in size. The light trapping, even when probing an isolated nanoparticle, is revealed by an enormous amplification of the Raman yield of up to 10(8) times that of a similar Si bulk volume. The mechanism conceived and optimised for obtaining such a result was related to the capability of a Si octahedron to trap the light because of its geometrical parameters. Furthermore, Si-NPs act as very efficient light scatterers not only for the direct light beam but also for the trapped light after it escapes the nanoparticle. These two effects are observed, either superimposed or separated, by means of the Raman yield and by photoluminescence enhancements. The inductively coupled plasma synthesis process performed at a temperature of only 50 °C allows for the ubiquitous use of these particles on several substrates for optical and photovoltaic applications.
authors: CNR-IMM, Strada VIII n°5, 95121 Catania, (Italy).
authors: Giovanni
authors: G
authors: Mannino
authors: CNR-IMM, Strada VIII n°5, 95121 Catania, (Italy).
authors: Alessandra
authors: A
authors: Alberti
authors: CNR-IMM, Strada VIII n°5, 95121 Catania, (Italy).
authors: Rosa
authors: R
authors: Ruggeri
authors: CNR-IMM, Strada VIII n°5, 95121 Catania, (Italy).
authors: Sebania
authors: S
authors: Libertino
authors: Università di Catania, Dipartimento di Fisica e Astronomia, Via Santa Sofia 64, 95123 Catania, (Italy).
authors: Agata R
authors: AR
authors: Pennisi
authors: Università di Catania, Dipartimento di Fisica e Astronomia, Via Santa Sofia 64, 95123 Catania, (Italy).
authors: Giuseppe
authors: G
authors: Faraci