Study on broadband high gain integrated amplifiers and circuits using Er doped garnet crystal thin-film

在此基础上，利用掺Er石榴石晶体薄膜进行了紧凑、宽带、高增益集成放大器和电路的研究，取得了以下成果。对于利用射频溅射系统在石榴石上制备掺Er和Er-Yb共掺石榴石薄膜的器件，以及在GGG衬底上制备Er：YIG薄膜的器件，我们对各种成分和晶体结构进行了评估，并与传统的掺Er：YGG晶体薄膜进行了比较。我们最终得出了最合适的材料结构的结论。我们用LPE制备了Ce、Bi掺杂的YIG晶体薄膜，这种薄膜在晶体质量和生长控制方面都有很大的优势。研究了晶体薄膜的制备条件，并对其进行了优化。2.测量了掺Er石榴石薄膜的吸收光谱和荧光光谱，得出了最合适的泵浦和信号光波长。利用1.5μm波段波长可调谐激光测量…比较了最合适波长下的波导损耗，测量了最合适波长下的吸收损耗。3.对稳态条件下的静态放大特性进行了理论分析。在Er/Yb共掺的情况下，与仅掺Er的情况相比，我们获得了较高的单位长度增益，并且发现器件小型化是可取的。我们发现，随Yb离子的不同，放大增益随波导长度的变化而变化。并对Yb离子浓度进行了优化。4.研究了Er/Yb共掺石榴石晶体薄膜光波导放大器中泵浦光和信号光的静态传输特性。并对其增益和噪声特性与离子浓度和传播距离的关系进行了研究。利用高精度的激光扫描系统，制作了三维光波导器件，提高了放大增益和效率。考虑到增益谱和光波导色散特性，利用含时三能级和四能级速率方程，对稀土离子超短光脉冲放大的跃迁响应进行了数据分析。对掺Er和掺Er-Yb放大光波导进行了对比研究，发现放大后的出射脉冲形状将变为非线性。对纳秒级和皮秒级光脉冲的动态增益特性进行了理论分析，并对飞秒级光脉冲的动态增益特性进行了分析。我们已经研究了信息处理器(超高速、超并行计算机)的实现，使光通信信号的超高速增益和高速计算处理成为可能。未来，我们必须研究如何提高放大特性、效率、带宽和紧凑性。根据研究项目的结果，有可能进行更全面的研究和开发。较少

Based on examination, we could obtain the following results in research of compact, broadband and high gain integrated amplifiers and circuits using Er doped garnet crystal thin-film.1. As for devices which Er doped and Er-Yb co-doped garnet thin film on YAG using the RF sputtering system, and device which Er:YIG thin film fabricated on GGG substrate, we evaluated many kinds of composition and crystalline structure, and compared those with conventional Er doped YGG crystal thin film. We finally reached a conclusion on the most suitable material structure. We have fabricated Ce, Bi doped YIG crystal thin film using LPE which was superior in crystal quality and growth controlling. And investigated the condition of fabricating crystal thin film, optimized it.2.We have measured the absorption and fluorescence spectrum of Er doped garnet thin film, and reached conclusion on the most suitable pump and signal light wavelength. Further more, using 1.5 μm region wavelength tunable laser measure … More d the loss of the waveguide on the most suitable wavelength, measured the absorption loss on the most suitable wavelength.3.We have carried out the theoretical analysis of static amplification characteristics under the steady-state condition. In the case of Er/Yb co-doped, compared with the case of Er doped only, we obtained high gain per unit length, and found it is desirable to miniaturize the device. We found that the amplified gain depending on the length of waveguide varied with Yb ion. And we optimized Yb ion concentrations.4.We have carried out the investigation on the static propagating property of pump light and signal light on the waveguide amplifier of which using Er/Yb co-doped garnet crystal thin-film. And we have done the study that the gain and noise properties depend on ion concentrations and propagated distance. Using a high precision laser scanning system, we made three-dimension waveguide, and expected improvement of amplified gain and efficiency.5. Considered the property of gain spectrum and waveguide dispersion, we have carried out the data analysis on transitional response of ultra short optical pulse amplifications for rare-earth ion, using time dependence 3 energy level and 4 energy level Rate equation. Comparatively studied on Er and Er-Yb doped amplification waveguides, we found that the shape of amplified outgoing pulse will become nonlinear. We have carried out theoretical analysis of dynamic gain property in the optical pulse of nano- and pico-second durations, and also did in femto-second durations. We have studied on the realization of the information processor (ultra fast, ultra parallel computer) which makes it possible ultra fast optical communication signal gain and high speed computing process.In future, we must examine improvement of amplification characteristics, efficiency, broadbandness and compactness. According to the results of research project, it has become possible more comprehensive study and development. Less