| The communication and interconnect with photon as the carrier of information is a new information technology after 1970's. This new technology has brought a revolution to the information traffic which promotes the human being from industrial society to information society. The light devices play a key role in the information traffic. The 1.54μm emission from the intra-4f transition of Er ions has attracted much attention on the optical information traffic. This wavelength is corresponding to the low-loss for Si-based devices and safe to the human's eyes. The studies are mainly focused on the charactistic spectra of the Er-doped materials, and how to improve the luminescence efficiency of Er doped materials, and devices on the energy transfer mechanism and physical and chemical environment for Er luminescence. The maily studies are Er-doped Al2O3 thin film with nc-Si, Er-Tm-codoped CABAL glasses.The first part is investigating the nanostructured Si (nc-Si) crystallization evolution on the Er3+ luminescence in the Er-doped Si/Al2O3 superlattices fabricated by using pulsed laser deposition (PLD) technique. The Raman scattering, X-Ray Diffraction and Transmission Electron Microscopy measurements are used to analyze the micro structure characteristics of the nc-Si during the annealing treatment processes. The maximum photoluminescence intensity is achieved in the sample with ultrathin nc-Si sublayers at the annealing temperature 600-700℃, where the number and the size of Si nanocrystals, the interaction distance and the local environment of Er3+ are well controlled. It has been observed that the nc-Si sensitized indirect excitation dominates the luminescence process even under resonant pumping.The second part is investigating the Er-only, Tm-only and Er-Tm-codoped CABAL glasses were prepared by CaCO3 (Panreac 99.0%), B2O3 (Merck 99.935%), Al2O3 (Alfa 99.9%), Tm2O3 (Aldrich 99.99%) and Er2O3 (Aldrich 99.99%) raw materials in a melting method. The characteristic emission around 1530nm with a FWHM of 50nm from intra-4fEr3+transitions was observed for the Er-doped CABAL glasses. An absorption peak at 1530nm was found from the absorption spectrum, which confirmed the truth of 1530nm is a result of direct transition process.In the third part, Er and Si codoped ZnO film was synthesized by cosputtering from separated Er, Si, and ZnO targets. It is shown that the maximum intensity of Er3+ related 1.54μm PL is obtained when the Si:ZnO/Er:Si:ZnO/Si:ZnO sandwiched multilayer film and the alternate Er:ZnO/Si:ZnO multilayer film were annealed at 1000℃and 950℃, respectively. The Er3+related 1.54μm PL intensity of the multilayer film, which can be attributed to the presence of the silicon nanocrystals (Si-NCs) that could act as sensitizers of Er3+ ions, is higher than that of the Er:ZnO monolayer film. The PL of the sandwiched multilayer film and the alternate multilayer film were measured under different temperature (15-298K).In the fourth part, Er-Tm-codoped CABAL glasses were investigated with a pump light of 795nm at room temperature. It is shown that by controlling the [Tm]/[Er] concentration ratio a fairly flat emission with a bandwidth of 370nm can be achieved. The broadband emission is formed by three bands centered at 1.4,1.5 and 1.8μm, which are related to the emission from the Tm3+:H4â†'3F4, Er3+:4I13/2â†'4I15/2 and Tm3+: 3F4â†'3H6 transitions, respectively. It was observed that the emission intensity at 1.46, 1.53 and 1.80μm decreases monotonically as increasing the temperature from 15 to 298K (room temperature) at lower concentrations, however, for the high-concentration samples, the peak emission at 1.80μm (Tm3+:3F4â†'3H6) was found to increase with the increasing temperature. The energy transfer (ET) processes between Er3+ and Tm3+ ions was identified by analying the fluorescence lifetime of corresponding energy level. This study has revealed the average critical distance of energy transfer between Tm3+ ions (RTm0), Er3+ and Tm3+ ions (Rer0)) was approximate to be lnm. Meanwhile, Near-infrared photoluminescence (PL) of calcium boroaluminate (CABAL) glasses codoped with Er2O3 and Tm2O3 has been investigated by dual-wavelength pumping at 795 and 476nm.In the last part, the CABAL glasses were improved by a dry method to reduce the composition OH-. The peak emission of 1800nm was enhanced from a Tm-doped CABAL glasses. From the absorption spectra, the absorption cross section of OH- was calculated. Furthermore, the influence of OH- to 1800nm was explained. |
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