【作者】 曹迎春；

【导师】 陆培祥；

【作者基本信息】 华中科技大学 ， 物理电子学， 2009， 硕士

【摘要】 光子晶体光纤作为一种新型的光纤,包层由折射率周期分布的二维光子晶体组成。由于其在非线性方面的诸多优势,一提出便受到广泛的关注。一方面,研究人员通过设计不同的结构,从理论或实验上进一步探索光子晶体光纤的新特性;另一方面,基于光子晶体光纤的通信器件也相继得到研究,有的已经开始应用到实际的通信网络中,并发挥着重要的作用。基于此,我们认为研究光子晶体光纤的特性及其在通信中的应用是一个很有意义的课题。我们从光子晶体光纤的导光原理出发,深入研究了带隙光纤的能带结构,解释了空芯导光原理,对比了它与传统折射率导光的异同。通过归一化频率参数计算了光子晶体光纤的无截止单模特性,这是光子晶体光纤所特有的属性。利用有限元方法分析了光纤的模场分布,并分别计算了光子带隙光纤和折射率导引光子晶体光纤中的色散曲线。实验上研究了高非线性光子晶体光纤中的超连续谱产生,分析了超连续产生的机理和应用前景。在详细研究了光子晶体光纤中的受激布里渊散射效应和当前的光速减慢技术后,我们提出在极小核光子晶体光纤中利用受激布里渊散射效应实现全光缓存。该技术以声波作为信息缓存的载体,可实现缓存时间连续可调、还原效率高、脉冲失真度小、控制脉冲低等优点。并且通过数值模拟,验证了我们的想法,和普通大核光纤相比,在还原效率可比拟的情况下,用极小核光子晶体光纤可大大降低控制脉冲的功率,从而降低控制脉冲对光通信网络造成的潜在威胁,使系统更加稳定,在全光通信网络中具有很大的应用前景。更多还原

【Abstract】 Photonic crystal fiber (PCF), whose cladding is constituted with index-periodically arranged two dimensional photonic crystal, is a novel optical fiber. Because of its various advantages in nonlinear properties, PCF attracts many attentions once it was proposed. On one hand, researchers explore the new optical characteristics of PCF by designing different kinds of structures theoretically or experimentally; On the other hand, PCF-based communication devices begin to be investigated and made into application, some of which has its application in practical communication network and plays an important part in it.Therefore, we think that it is a meaningful work to research the optical properties of PCF and its applications in communication. Starting from the optical guiding principle of PCF, we deeply study the bandgap structure of photonic bandgap fiber, explain the guiding principle in air hole and compare it with the traditional index-guiding optical fiber. We also investigate the endless single mode properties of PCF from normalized frequency V parameter, which is the particular property of PCF. By using the finite element method, we study the mode distribution of index-guiding PCF and photonic bandgap fiber, respectively, and then calculate the dispersion curve and birefringence of them. In addition, we experimentally investigate the supercontinuum generation in our high nonlinear PCF, and analyze the mechanism and application prospect of supercontinuum generation.After detailed investigating stimulated Brillouin scattering effect in PCF and the current slow light technology, we propose a new method that realizing all-optical buffering in ultra small-core PCF via stimulated Brillouin scattering. By using the long-lived acoustic wave as the temporal information carrier during the all-optical buffering, we can achieve the buffering with tunable delay, high retrieval efficiency, small pulse distortion and low control pulse power. To prove the validity of our assumption, we numerically simulate the buffering process by solving the coupled wave equation. It is shown that we can greatly reduce the needed control power while keeping the same retrieval efficiency when buffering in our small-core PCF instead of traditional optical fiber. It promise a brighter application in communication network because the reduced control power will take less damage to all-optical network and make the system more steady.更多还原