Synthesis, Characterization Of Er³⁺-Ce³⁺ Co-doped Fluoride Nanocrystals For Optical Waveguide Amplifiers

Nowadays, our way of life has been greatly changed with the widespread use ofoptical communication networks. It has been widely accepted that all-opticalcommunication would become available in the near future. In the process of opticalcommunication, the energy loss is inevitable, thus the optical amplifiers are widelyused in long distance transmission. The optical amplifiers can amplify the opticalsignal without any conversion between optical and electric signal. Optical signalamplification technology is the most effective method of the energy losscompensation. In comparison with the inorganic ones, the organic optical waveguideamplifiers have drawn more and more attentions for their advantages such as lessenergy loss, more convenient to change the index of refraction, better plastic property,easier technic and cheaper in price.This paper is mainly about the fundamental research in synthetic material of corelayer and device fabrication in the field of optical waveguide amplifiers, include thefollowing items:We synthetized the NaYF4:Yb³⁺, Er³⁺nano-particle with three methods:solvothermal method by using rare-earth stearate as precursor, Sodium hydroxide oleic acidethanol system hydrothermal method, and thermal decomposition method. In order to guide our synthetic method and get a better core layer material, we characterized thestructures, appearances and optical spectrums of these samples, and made acomparison in the properties of particle size, solubility, appearance, dispersion andoptical spectrum, when doing this we considered the connection with the amplifiers.We made a conclusion that α-phase NaYF4synthetized by thermal decompositionmethod is much better in all properties.After synthetizing the NaYF4:Yb³⁺, Er³⁺nano-particles, we changed the dopingratios, and found a trend that the luminescence of Er³⁺depends on the Ce³⁺concentration. With a certain Ce³⁺concentration, there is a dramatically reduction ofEr³⁺Conversion emission, and the emission near1550nm is enhanced to six time thanbefore. This will provide a simple and effective approach to enhance the amplificationefficiency of optical waveguide amplifiers.We explored the process of preparing organic waveguide amplifier usingPMMA-GMA as under cladding or using SU-8as core layer of waveguide. Thencharacterized the appearance, did the optical testing of the samples. Later we focusedon the later method. After the device being polished, making a reducing on loss, wetested the gain characteristics of the device. Now we can get a stable gain of about2dB/cm.In this thesis, we did specific research in the doping material of waveguide corelayer in many aspects, and got a series of practical results. The exploration ofpreparation method, the characterization and testing of the system laid the foundationfor the preparation of high-performance organic waveguide amplifiers.