Tm ~ (3 +) / Yb ~ (3 +) co-doped oxyfluoride glass ceramics waveguides Preparation and optical properties

Title: Tm ~ (3 +) / Yb ~ (3 +) co-doped oxyfluoride glass ceramics waveguides Preparation and optical properties Author: Qin fast Degree-granting unit: Jinan University Key words: rare earth doped;; glass ceramics;; upconversion;; fluoride microcrystalline;; planar waveguide Summary: As both oxide glass high mechanical strength, chemical stability and good, but also the low phonon energy fluoride, luminous efficiency of high Magnetic lifter performance, rare earth doped transparent oxyfluoride glass ceramics in the laser, display and optical communication fields is good prospect, which led to the close attention of researchers. This article was prepared by high temperature melting Tm3 + / Yb3 + co-doped Na2O-La2F6-Al2O3-SiO2 transparent glass-ceramics, the main research and its fluorescence characteristics of waveguide performance. (1) X-ray diffraction, transmission electron microscopy, absorption and fluorescence spectra of different heat treatment methods discussed in the rare earth-doped glass ceramic microstructure and luminescent properties. The results show that the glass substrate after heat treatment to generate a LaF3 nanocrystals, being evenly distributed in the matrix. With the heat treatment temperature (650,670,700 ℃), LaF3 crystallite size increases (14.2,20.7,24.4 nm), the transparency of the glass matrix of a corresponding decline (86,84,79%), when temperature reaches 750 ℃ ​​C, the loss occurs through the phenomenon. In the 980 nm LD excitation at the center of the glass ceramic apparent at 475,650,796 nm upconversion fluorescence, corresponding to the Tm3 + 1G4 → 3H6, 1G4 → 3F4 and 3H4 → 3H6 level transition. After heat treatment a large number of rare earth ion concentration in the lower phonon energy LaF3 crystallites, as it can be observed in the bright blue upconversion luminescence. Upconversion mechanism for the discussion of that blue (475 nm) light-emitting part of three-photon absorption, while the red light (650 nm and 796 nm) are two-photon absorption. In the 980 nm LD excitation also detected the infrared glow of glass ceramics 1.47μm, corresponding to the Tm3 + 3H4 → 3F4 level transition, and its bandwidth is about 100 nm, but the light intensity relative to the much weaker upconversion, because Tm3 + in 1.47μm and 796 nm light the existence of competition, the branching ratio for the 0.083:0.893 light. (2) prepared by ion-exchange glass and glass ceramics planar waveguides, comparative study of legal trouble through the prism of both m-line http://www.999magnet.com/products/131-magnetic-lifter spectrum, the refractive index distribution and diffusion depth, test results showed that the two matrices have a good The ion exchange properties. In KNO3 and AgNO3 (99.5:0.5 molar ratio) mixed in the molten salt, 340 ℃, respectively exchange 3min, 3.5min, 4min, 4.5min, glass and glass-ceramic waveguide refractive index change An was 0.0116 ± 0.00095 and 0.0121 ± 0.000925, diffusion coefficients were 0.054μm2 / s and 0.071μm2 / s. This study shows that rare-earth-doped transparent glass ceramic silicate oxygen fluoride upconversion and ion exchange has excellent performance, so that in the conversion of laser materials and optical communication has potential applications. Degree Year: 2010