【作者】 王肇颖；

【导师】 李世忱；

【作者基本信息】 天津大学 ， 物理电子学， 2004， 博士

【摘要】 时分复用与波分复用技术结合是未来全光网络的发展趋势，于是围绕全光网的功能器件研究成为持续性研究热点。本文主要围绕超短脉冲光源产生技术和全光波长变换技术取得如下研究成果：一、非线性偏振旋转被动锁模掺铒光纤激光器的研究1. 理论分析了被动锁模光纤光腔参数对输出脉冲特性的影响。2. 实验得到重复频率13.9MHz、脉宽1.5ps的稳定锁模脉冲输出。首次实现被动锁模限变脉冲在9nm范围内连续可调谐。利用50m普通单模光纤（SMF）将脉冲压缩到750fs，并观察到高阶孤子分裂现象。二、主被动锁模掺铒光纤激光器的研究1. 理论上，详细分析了色散不平衡光纤环形镜（DI-NOLM）的开关特性，以及入射脉冲参数、环形镜参数对DI-NOLM透射率特性的影响。2. 完成基于DI-NOLM的“8”字型主被动锁模光纤激光器实验，得到脉宽11ps的10GHz锁模脉冲序列和幅度均匀的20GHz和30GHz脉冲序列。三、光纤超连续谱（FSC）产生的研究1. 通过数值计算，从光纤各种非线性效应、光纤参数以及泵浦脉冲参数三个方面分析了影响超连续（SC）脉冲谱特性的因素。2. 用被动锁模光纤激光器泵浦不同色散特性和长度的光纤，完成SC产生和谱切片实验。实现谱展宽大于450nm，长波段扩展到1780nm以上（受测试仪器限制），在百纳米范围段的不平坦度<(0.25dB，达到国内最好水平。四、基于半导体光放大器（SOA）的四波混频全光波长变换研究1. 理论上推导出重要物理量对波长变换效率、信噪比的影响。分析了垂直双泵浦机制可在很宽的频率差范围内得到恒定的效率和信噪比。2. 在实验上，实现了对电吸收调制激光器10GHz脉冲的波长变换。在国内首次用正交泵浦方案实现泵光与信号光波长差52nm范围内变换效率变化量<3.88dB。五、C带掺铒光纤放大器（EDFA）的增益平坦研究1. 首次提出利用普通单模光纤通过缠绕产生双折射，并与不对称放置的偏振控制器构成光纤环形镜实现EDFA增益平坦滤波的可行性。2. 在实验上，首次运用上述方法实现了EDFA的自发发射谱34nm范围内<(0.6dB的不平坦度，为当目前类似方案可以获得的最好水平。更多还原

【Abstract】 The combination of optical time division multiplexing (OTDM) and wavelength division multiplexing (WDM) technologies will be the trend in near future optical network, which put the researches on components into focus. This dissertation is focused on ultra-short pulse sources and all optical wavelength conversion, which include:Nonlinear polarization rotation passively mode-locked fiber laser Influence of cavity parameters on output pulse width, chirp, bandwidth and stability is investigated numerically.Stable, self-starting 1.5ps mode-locked pulse at 13.9MHz repetition rate is obtained. Transform-limited pulse with wavelength continuously tunable over 9nm is obtained for the first time. The output pulse is compressed to 750fs with 50m single mode fiber (SMF) and beautiful division figure of high-order soliton is observed. Actively-passively mode-locked fiber laser with a DI-NOLMSwitching characteristics of dispersion-imbalanced nonlinear optical loop mirror (DI-NOLM) is investigated numerically in detail.11ps stable mode-locked pulse train and 20GHz, 30GHz harmonic mode-locked pulses with uniform amplitude are obtained with the figure-eight structure.Fiber supercontinuum (FSC) pulse source The influences of nonlinear effects of fiber, fiber parameters and pump pulse parameters on superconitnuum (SC) spectrum are studied numerically.SC is generated and sliced in fibers with different dispersion characteristic and length. More than 450nm 20dB bandwidth is generated with uniformity within (0.25dB over hundreds of nanometers for the first time.All wavelength conversion based on FWM in SOAInfluence of important parameters on conversion efficiency and signal-noise ratio (SNR) are studied numerically. It is also analyzed that constant efficiency and SNR can be obtained in a wide detuning range with orthogonally polarized pump mechanism. The output 10GHz pulse of electro-absorption modulated laser (EAL) is wavelength converted by using FWM in SOA. Meanwhile, only 3.88dB <WP=4>fluctuation of conversion efficiency over 52nm wavelength detuning range is obtained by using orthogonally polarized pump for the first time.Gain-flattening of erbium-doped fiber amplifier with fiber loop mirror (FLM)The method of EDFA gain flattening using a FLM acting as a wavelength filter is analyzed in theory. The feasibility of using closely twisted SMF generating birefringence to construct FLM is brought forward for the first time.Experimentally, an ASE flatness of (0.6dB within 34nm is obtained, which is the best result with similar method until now.更多还原