【作者】 李彤；

【导师】 张大明；

【作者基本信息】 吉林大学 ， 微电子学与固体电子学， 2009， 硕士

【摘要】 掺铒光波导放大器(EDWA)能够有效地补偿光信号的损耗,具有增益高、体积小、结构紧凑、便于集成、成本低的优势,是具有相当发展需求和前景的新型通信器件。聚合物波导材料制备的EDWA工艺简单、成本低,材料种类多样,折射率差易于调整,制作的器件轻巧、机械性能好,适用于制作高密度集成器件,是近年来受到重视的一个新的研究热点。本文对铒镱共掺有机聚合物光波导放大器进行了研究。首先对光放大技术的发展、EDWA的产生及国内外研究进展进行了介绍,指出了聚合物材料在用于制作光波导放大器上的优势。研究了EDWA的工作原理与基本结构、引入敏化剂镱离子的意义、光波导设计、Judd-Ofelt理论及对EDWA增益特性的模拟。合成并表征了三种铒配合物,分析其光谱特性、热稳定性。制备了铒的有机配合物及其掺杂的P(MMA-GMA)聚合物材料,分析其光谱特性。针对材料设计单模波导结构并模拟放大器的增益特性,讨论了放大器增益特性的影响因素。采用铝掩模光刻结合反应离子刻蚀技术制备铒配合物掺杂的P(MMA-GMA)聚合物光波导,利用实验室构建的光波导近场光斑测试系统与增益测试系统对光波导进行测试,获得了两种波导结构的近场输出光斑,并在泵浦光(980 nm,133mW)激励下,在15mm长,截面尺寸8μm×4μm的矩形光波导器件上观测到了信号光(1550 nm,2mW) 0.7dB的增益。最后,分析信号的放大现象微弱且不稳定的原因,指出下一步要着重解决的问题和方法。本论文在有机聚合物光波导放大器的材料合成与表征、器件的结构设计、理论模拟、工艺制备及性能测试方面做了一些研究工作,为研制高性能、实用化的有机聚合物平面光波导放大器奠定了基础。更多还原

【Abstract】 It has been widely acknowledged that all-optical communication would be the prime method in optical communication systems. The integrated optical amplifiers can amplify the optical signal without any conversion from light to electricity. Optical signal amplification technology is the most effective method for the loss compensation. It is a milestone in the history of the development in optical fiber communication systems and a key to the realization of all-optical communications.Erbium doped optical waveguide amplifier （EDWA） is another new kind of optical amplifier followed the Semiconductor optical amplifier （SOA） and Erbium doped fiber amplifier （EDFA）. The research of optical waveguide amplifiers used in optical communications have drawn more and more attentions for their high gain, small size, compact structure, convenient integration and low loss.The optical waveguide amplifiers in the 1.55μm region are mainly made of Er-doping inorganic phosphate and silicate glasses, and have already commercialized. However, the fabrication process is complex and integrating with other photonics devices is very difficult. Compared with conventional inorganic waveguide materials, polymer waveguide materials have advantages in easy process, controllable refractive index and easy integration etc. For these reasons, the research on polymeric optical waveguide amplifier is becoming an increasing focus.This dissertation is a fundamental research on Erbium-Ytterbium co-doped polymeric optical waveguide amplifier. Several kinds of Er-doped complexes and doping-type active polymer were prepared. The photolithography method and reactive ion etching process were used to prepare the optical waveguides. The output near-field profile and optical gain of the optical signal in 1550nm region were measured. The main contents are listed as following:1. First, the developing process and achievement in recent years about fiber optical communication and EDWA were reviewed. Compared with the three kinds of optical amplifiers, it is pointed out that erbium-doped waveguide amplifier is conducive to the integration of optical functions because of its advantages such as high gain per unit length, easy fabrication method, lower cost, low noise figure, small polarization correlation, no channel crosstalk and so on. A variety of integrated optical communication devices are successfully fabricated because erbium-doped waveguide amplifier could be integrated with isolation, phased-array waveguide, multiplexers, modulators, optical switches, optical cross connect and so on. Second, we analyzed the advantages of organic polymeric waveguide amplifier. Then the new researches of the erbium-doped organic polymer materials and erbium-doped optical amplifiers at home and abroad have also been reviewed.2.The energy level structure of Er³⁺ was analyzed. The basic structure and working principle of EDWA and the improvement of optical gain using Erbium-Ytterbium co-doped technology were introduced. The basic theories of designing a rectangular optical waveguide and the Judd-Ofelt theory were studied. Based on optical amplifying theory of excited emission, we set up the rate equations and propagation equations of optical power, which were used for the numerical simulation of the gain.3. The key point of research on polymer optical amplifiers is the preparation of active polymer materials with high quantum efficiency. Erbium organic complexes derived from 1,10-phenanthroline（Phen） with acetylacetone（AcAc） or methacrylic acid （MA） were synthesized and identified by elemental analysis. The UV-vis absorption and FTIR spectra measurements have been employed for all the erbium complexes.Near infrared （NIR）photoluminescence properties,such as luminescence intensity and effective bandwidth of the erbium complexes were also studied.Using these complexes, we prepared doping-type active polymer. By measuring the absorption and the photoluminescence spectra of the polymer materials, we observed some typical absorption and photoluminescence peaks of Er³⁺ ions. The full width at half maximum （FWHM） was more than 80nm centred around 1535nm. Using the Judd-Ofelt theory, we calculated the spontaneous transition probability and the fluorescence lifetime of this polymer material. The fluorescence lifetime was about 13ms. Using X-ray photoelectron spectroscopy （XPS） analysis, we identified the ratio of Er³⁺ to Yb³⁺.4. We used ellipsometry to measure the film-formed characteristic and refractive index of the material. According to the material’s refractive index and effective index method, single-mode waveguide structures were designed to meet the 1535 nm and 980 nm laser propagation. The mode field distributions in these waveguides were analyzed and the overlapping factors were calculated. Based on optical amplifying theory of excited emission and a six-level system model for Er3+-Yb3+co-doped waveguide amplifier, we set up the rate equations and propagation equations of optical power, and numerical simulated the gain. Based on the simulation results, we analyzed influencing factors of the gain, such as pump power, signal power, Er/Yb-doped concentration, overlapping factors etc.5. The fabrication technique of waveguide amplifiers is the key process, which directly influences the quality of the waveguide. We selected the photolithography and reactive ions etching process and prepared the doping-type active optical waveguides. Then, two different optical waveguide structures were designed and the fabrication processes were described in detail. The surface characters of polymeric optical waveguide amplifiers were showed by the microscope photos. Taking into account of the optical waveguide-fiber direct coupling, we designed and constructed a system which was used to test the output signal and the gain of waveguide amplifier. With this system, the output near-field profiles were measured. When the pump power is 133 mW and the signal power is 2 mW, a gain of approximately 0.7 dB was observed at 1550nm in a 15-mm-long waveguide, which dimension was 8μm×4μm.6. Due to the low Er-doping concentration and photoluminescence quantum efficiency, a real and applicable amplifier still needs further research. The key problems are how to enhance the solubility and the dispersity of the Erbium organic complexes in the polymer matrix and how to reduce the effect of concentration quenching and the vibration quenching caused by O-H and C-H groups.Some basic research on Erbium-Ytterbium co-doped polymeric optical waveguide amplifier, such as the synthesis and characterization of active polymer materials and the structural design, simulation, fabrication processes and performance test of devices, has been down in this dissertation. It laid the foundation for the development of high-performance and practical polymeric planar optical waveguide amplifiers.更多还原