Green synthesis of silica-coated gold nanoparticles employing femtosecond laser, solid targets, and water.

Gold nanoparticles are widely used in biomedical applications due to their unique properties. However, traditional synthesis methods generate contaminants that cause cytotoxicity and compromise the biocompatibility of the nanomaterials. Therefore, green synthesis methods are essential to produce pure and biocompatible nanoparticles, ensuring their effectiveness in biomedical applications.

Strong enhancement of effective refractive index in structured colloids (TiO@Silica): Localization of light.

We use non-resonant Raman scattering to demonstrate a large enhancement of the effective refractive index experienced by Raman photons in a scattering medium comprising spatially-correlated photonic structures of core-shell TiO@Silica scatterers mixed with silica nanoparticles and suspended in ethanol. We show that the high refractive index extends outside the physical boundary of the medium, which is attributed to the evanescent contributions of electromagnetic modes that are strongly localized within the medium. Notably, the effective enhancement can be observed even at very low intensities of Raman emission.

1337 nm Emission of a Nd-Doped TZA Glass Random Laser.

Random lasers have been studied using many materials, but only a couple have used glass matrices. Here, we present a study of zinc tellurite and aluminum oxide doped with different percentages of neodymium oxide (4 wt.%, 8 wt.

Ordered photonic colloidal suspensions.

Ordered photonic structures (photonic crystals) have seen increasing interest in recent years due to their potential applications, which depend on fabrication technologies suitable for mass production. In this paper, we studied by light diffraction the order in photonic colloidal suspensions composed by core-shell ( @ ) nanoparticles suspended in ethanol and water solutions. Light diffraction measurements show order in these photonic colloidal suspensions, being stronger in ethanol compared with suspensions in water.

Localization of light induced in ordered colloidal suspensions: powerful sensing tools.

We study the light-matter coupling by Raman scattering in colloidal suspensions composed by core-shell TiO@Silica (Rutile@Silica) nanoparticles suspended in ethanol and water solutions. Strong enhancement of the Raman signal per particle is observed as [TiO@Silica] is increased above a threshold, being stronger in ethanol suspensions. Moreover, above this [TiO@Silica] threshold, the optical transmittance of the ethanol suspension starts to be considerably lower than in water, despite scattering strength being higher in water.