White Light Emission from Thin-Film Samples of ZnO Nanocrystals, Eu and Tb Ions Embedded in an SiO Matrix.

In this work, a method was developed to determine the concentration of Eu and Tb ions in a thin-film sample of SiO, co-doped with ZnO-nanocrystals (ZnO-nc), to produce a sample of any desired colour in the International Commission on Illumination (CIE) colour space. Using this method, a white light emitting sample was fabricated. The thin-film sample combines red, green and blue emissions from the Eu ions, Tb ions and ZnO-nc, respectively, to create white light or light of any desired colour.

Energy Transfer Efficiency from ZnO-Nanocrystals to Eu Ions Embedded in SiO₂ Film for Emission at 614 nm.

In this work, we study the energy transfer mechanism from ZnO nanocrystals (ZnO-nc) to Eu ions by fabricating thin-film samples of ZnO-nc and Eu ions embedded in a SiO₂ matrix using the low-cost sol-gel technique. The time-resolved photoluminescence (TRPL) measurements from the samples were analyzed to understand the contribution of energy transfer from the various ZnO-nc emission centers to Eu ions. The decay time obtained from the TRPL measurements was used to calculate the energy transfer efficiencies from the ZnO-nc emission centers, and these results were compared with the energy transfer efficiencies calculated from steady-state photoluminescence emission results.

Study of energy transfer mechanism from ZnO nanocrystals to Eu(3+) ions.

In this work, we investigate the efficient energy transfer occurring between ZnO nanocrystals (ZnO-nc) and europium (Eu(3+)) ions embedded in a SiO2 matrix prepared using the sol-gel technique. We show that a strong red emission was observed at 614 nm when the ZnO-nc were excited using a continuous optical excitation at 325 nm. This emission is due to the radiative (5)D0 → (7)F2 de-excitation of the Eu(3+) ions and has been conclusively shown to be due to the energy transfer from the excited ZnO-nc to the Eu(3+) ions.

Annealing temperature and environment effects on ZnO nanocrystals embedded in SiO2: a photoluminescence and TEM study.

We report on efficient ZnO nanocrystal (ZnO-NC) emission in the near-UV region. We show that luminescence from ZnO nanocrystals embedded in a SiO2 matrix can vary significantly as a function of the annealing temperature from 450°C to 700°C. We manage to correlate the emission of the ZnO nanocrystals embedded in SiO2 thin films with transmission electron microscopy images in order to optimize the fabrication process.

Optical and physical properties of solgel-derived GeO2:SiO2 films in photonic applications.

The functionality of optical components relies heavily on the composition-dependent properties of germanosilicate materials, which include the refractive index, photosensitivity, and microstructural properties. Recent studies and parallel developments are presented of germanosilicate films with composition x of Ge content (i.e.