【作者】 陈曦；

【导师】 张茹；

【作者基本信息】 北京邮电大学 ， 物理电子学， 2009， 硕士

【摘要】 随着人们对信息需求的快速增长,光纤通信技术成为信息高速公路的核心和支柱,目前光纤网络正朝全光网络方向发展。基于高非线性光纤四波混频效应（FWM,Four-Wave Mixing）的全光纤波长变换技术因具有宽带的多信道同时变换能力以及远大于电子器件速率极限的超高响应速度等优点,在高速WDM网络中展示了极为广阔的应用前景。因此,高非线性光纤逐渐受到了人们的重视,而对于高非线性光纤的研究也随之成为了功能光纤研究领域的一大热点。本文首先概述了非线性光纤的研究现状;同时,将纳米技术与光纤制备技术相结合,选用尺寸在十几个纳米的纳米级InP微粒,利用改进的化学气相沉积法,研制出了新型的掺纳米InP微粒光纤,此种光纤较普通光纤的特殊之处在于:在普通光纤的纤芯中掺入了纳米级InP微粒。通过一系列的实验测定,测得该光纤的纤芯中,InP的掺杂浓度为0.1%,掺杂纳米微粒的大小约为20nm,且该光纤具有一定的通光性能。基于以上实验,根据有限元法分析思想,建立了微粒在纤芯中均匀分布的光纤纤芯模型,并通过FEMLAB仿真工具,计算了纤芯中关于电磁场的能量分布图,并计算了光纤的有效折射率为n_eff=1.400,以及其有效面积为A_eff≈10.01μm²,说明该光纤已经具有较普通光纤更小的有效模式面积以及非同寻常的折射率分布。根据以上结果,计算了光纤的非线性系数约为γ≈10.53W^-1/km,说明了该光纤具有较强的非线性特性。基于以上研究,对本课题工作进行了分析总结,得出:一个更加周期性的掺杂微粒分布以及更小的掺杂浓度会更有利于减小光纤中的传播损耗以及获得更佳的光控性能,这样也会获得更强的非线性特性,使这种光纤能更好的应用于各种光电子器件中。本课题的工作也为后续的研究工作指明了方向。最后,文章对此种非线性光纤的应用前景做出了分析和展望,相信此种光纤必定会为新型的非线性光纤的研究开辟新道路。更多还原

【Abstract】 With the rapid growth of the information needs nowadays, optical communication technology becomes the core of the information highway, and currently fiber optic networks are moving in the direction of the development of all-optical networks. The all-optical wavelength conversion technology, which based on the FWM （Four-Wave Mixing） technology of high nonlinear fibre, has the advantages of broadband multi-channel transform capacity, ultra-high response speed that more excellent than the electronic devices’ rate limit, shows the wild usage in WDM networks. Therefore, the research on high nonlinear fibre becomes a hot spot of the functional fibre research filed.First of all, this article states the overview of nonlinear optical research. Then combined the nano-technology with the fibre fabrication technology, the InP particles at nano-scale is chosen to fabricate the novel optical fibre doped with InP through a modified MCVD （Modified Chemical Vapor Deposition）. Compared with ordinary optical fiber, this fibre is special that it has InP particles doped in its core. Through experiment, the consistency of InP is approximately 0.1% in the core, and the particles scale is about 20nm, and the fibre has an excellent waveguide characteristic. Based on the experiment, a core model that the particles uniformly distributed in is built, and obtained the effective refractive index n_eff = 1.400 and the effective core area A_eff≈10.01μm² that is less than ordinary fibre and different with ordinary refractive index distribution. According to the result above, the nonlinear coefficientγ≈10.53W^-1/km is got, and this result reflects that this novel optical fibre has a strong nonlinearity.Based on the research above, we got this conclusion that, a more cyclical distribution and less dense of the particles in the core will have a less propagation loss, a better light control performance, and a higher nonlinearity, so that it can be easily used in multiple optoelectronic devices. This research leads a way for continuous research.At last, this article gives a brilliant future of this fibre and believes that this kind of fibre can open up new roads in nonlinear fibre field.更多还原