| In the 21st century, human society has entered the information epoch with the features of high capacity, high broadband and high velocity, at which the integrated optics and optical communication develop at an unprecedented rapid. Erbium-doped planar waveguide amplifiers (EDWA) are an important part of integrated optics and optical communication system. EDWA can compensate for various types of optical loss in the process of transmission. Organic-inorganic composite materials, owing to their high flexibility, versatility, good thermal stability, integration, ease of processing and other features, have been prepared and investigated by numerous scientists. However, it is still considered to be a challenge for researchers to prepare rare-earth-doped silica nanoparticles via wet-chemistry. And few successful EDWAs have been demonstrated using erbium-doped Organic-inorganic composite materials. In this paper, we do some research on two parts. One part is to fabrication several different types of rare earth doped inorganic nanoparticles, another part is to synthesize waveguide polymer with the low optical loss. The theory and principles, preparation methods, and development of optical waveguide amplifiers materials have been reviewed in chapter 1.It is difficult to fabricate the lanthanide doped silica particles because the lanthanide ions will form insoluble lanthanide hydroxides in basic environment, at the same time, it is difficult to control the hydrolysis of the tetraethyl in acidic enviroment. In chapter 2, in order to resolve the problems, at first, we synthesized and characterized rare earth doped silica nano-particles by using the reverse emulsion formed by Span80, Tween60, cyclohexane and the lanthanide salt solution. Second, we fabricated monodispersive Eu(TTA)2(Phen)MA silica hybrid nanospheres by hydrolysis condensation reactions of tetraethyl orthosilicate in the presence of acid via sol-gel method modified by introducing water molecule into the TEOS-acetic acid system by moist airflow. At last, we fabricated the lanthanide ions-doped silica nanoparticles using two steps. We fabricated the porous silica particles and then dipped them in the solution of lanthanide salt. We characterized the structure and luminescence properties of the ions-doped particles using field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), photluminescence (PL) spectroscopy and so on.In chapter 3, for the first time, we developed a coating process to fabricate Eu3+-doped, Tb+-doped or Er3+-doped titania coatings deposited on silica nanoparticles. One modification of the process is that the diameter of the silica particles used to give the support for titania coating is nanosized. The other one is that the lathanide salts were added into the reactant mixture. The doping density is controlled by the concentration of the lanthanide ions in the reaction mixture. The typical Ln3+doping density is 0.052 at.%-0.535at.%. Indentical photoluminescence spectra were observed respectively from the Eu3+-doped, Tb3+-doped and Er3+-doped particles. The Er3+-Yb3+codoped core-shell titania@silica nanoparticles were prepared via this method. The diameter of the silica core is about 50 nm. The thickness of the titania shell is about 4 nm. A typical doping density of Er3+in the titania shell is 4.51 at.%, and the one of Yb3+is 12.20 at.%. The Er3+-Yb3+codoped core-shell titania@silica nanoparticles may find applications as optical materials because their excellent photoluminescence properties.In chapter 4, oleic acid-modified Er3+-Yb3+codoped LaF3 nanoparticles have been prepared and investigated. The scale of the diameter of the particles is 10-30nm. The results of TGA experiments tell us that the content of the solid can reach up to 85%. And then a fluorinated bis-phenol-A novolac resin for optical waveguide was synthesized based on 4,4-(hexafluoro-isopropylidene) diphenol, epoxy chloropropane and formaldehyde. A hybrid material was fabricated by mixing the nanoparticles and the polymer. The concentration of nanoparticles in hybrid materials was up to 30 wt%. The hybrid materials had good chemical resistance, thermal resistance and high glasstransition temperature, showing possibility for direct photolithography technique of waveguide amplifier structures.Any way, we fabricated several lanthanide ions doped inorganic nanoparticles via several methods and synthesized a new hybrid material with fluorinated photoresist and oleic acid-modified Er3+-Yb3+codoped LaF3 nanoparticles. The new hybrid materials we fabricated may find application on waveguide amplifiers. |
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