V型腔可调谐半导体激光器啁啾特性研究

发布时间：2018-08-23 08:41

【摘要】：信息交流在人们工作、生活和学习中发挥着越来越重要的作用。在未来的光通信网中,制作工艺、调制格式简单,波长可调谐,具有良好传输性能的半导体激光器将是必不可少的器件。直接幅度调制和电吸收调制以及马赫-曾德尔电光相位调制等外调制方式相比,是最简单、成本最低的一种调制格式。然而,半导体激光器的直接幅度调制通常伴随着人们不希望具有的正频率啁啾现象。调制信号在1550nm标准正色散单模光纤中传输时,正频率啁啾会使信号的脉冲展宽,这将严重限制光纤通信系统的传输速率和传输距离。人们渴望得到可以在密集波分复用城域网使用的具有波长可调谐功能和负啁啾特性的光发射机。本文首次发现并证实了直接调制可调谐半导体激光器的负啁啾现象。本文研究的多电极结构的直接调制可调谐V型腔激光器,在调制过程中,其有源区的载流子密度与输出光功率发生了巧妙地反向变化。因此,V型腔激光器输出的光信号具有负啁啾特性,从而实现了人们期盼已久的愿望。本文首先用时域行波模型模拟分析了直接调制过程中V型腔激光器的载流子密度与输出光功率之间的动态变化关系,从理论上说明了负啁啾的正确性；其次用光带通滤波方法测量了V型腔激光器的时域动态啁啾,从实验上测得了负啁啾结果,得到了与模拟分析一致的结论；最后分析了V型腔激光器的负啁啾特性对光信号在G.652标准单模光纤中色散的部分补偿作用,进一步证实了V型腔激光器的负啁啾特性。具有制作简单、结构紧凑、波长可调谐和直接调制负啁啾特性的V型腔激光器在未来光通信网中必将会有广阔的应用前景。
[Abstract]:Information exchange plays a more and more important role in people's work, life and study. In the future optical communication networks, semiconductor lasers with simple modulation format, tunable wavelength and good transmission performance will be essential devices. Compared with direct amplitude modulation (DAM), electroabsorption modulation (EAM) and Mach Zehnder electro-optic phase modulation (EOPM), it is the simplest and least cost modulation scheme. However, the direct amplitude modulation of semiconductor laser is usually accompanied by the chirp of positive frequency which people do not want. When the modulated signal is transmitted in the 1550nm standard normal-dispersion single-mode fiber, the positive frequency chirp will widen the pulse of the signal, which will seriously limit the transmission rate and transmission distance of the optical fiber communication system. It is desirable to obtain wavelength tunable optical transmitters with negative chirp characteristics that can be used in dense wavelength division multiplexing metropolitan area networks (DWDM). In this paper, the negative chirp of direct modulation tunable semiconductor lasers is first found and verified. In the process of modulation, the carrier density of the active region and the output optical power of the direct-modulated tunable V-cavity laser with multi-electrode structure have been ingeniously reversed. Therefore, the optical signal produced by the V-cavity laser has negative chirp characteristics, thus realizing the long-awaited desire. In this paper, the time-domain traveling wave model is used to simulate and analyze the dynamic relationship between carrier density and output optical power of V-cavity laser during direct modulation, and the correctness of negative chirp is explained theoretically. Secondly, the time-domain dynamic chirp of V-cavity laser is measured by optical band-pass filtering method. The negative chirp results are measured experimentally and the results are in agreement with the simulation analysis. Finally, the negative chirp characteristic of V-cavity laser is analyzed to compensate the dispersion of optical signal in G. 652 standard single-mode fiber. The negative chirp characteristic of V-cavity laser is further confirmed. The V-cavity laser with simple fabrication, compact structure, tunable wavelength harmonic and direct modulation negative chirp will have a broad application prospect in the future optical communication network.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN248.4

【相似文献】