【作者】 盛勇；

【导师】 沈廷根；

【作者基本信息】 江苏大学 ， 通信与信息系统， 2008， 硕士

【摘要】 光子晶体光纤由于它奇异的特性引起了国内外各方人士的关注。从理论上设计光子晶体光纤结构并研究其性质,对其实验室制备和应用研究具有重要的指导作用。但光子晶体光纤结构的复杂性使得人们很难对其特性作简单的解析,只能通过数值方法对其进行模拟分析。本论文的主要内容包括:1)本文着重研究了实心的光子晶体光纤的色散特性,尤其是在引入负折射材料的情况下,通过改变实心光子晶体的结构参数来找到色散的变化规律。2)用全矢量模型研究了六角形结构的空气芯光子晶体光纤的光子流可控特性,通过场图和曲线直观说明了能流和有效折射率以及有效模场面积内在的规律,有望用于制作高效率的光纤放大器,并主要讨论了随光纤结构参数孔距∧和层数的改变,选择合适的参数,它的有效折射率,有效面积以及能流分布达到最大值,以此得到光纤的光子流可控特性来优化光子晶体光纤的传输性能。3)用时域有限差分法研究了三角结构的等效负折射率光子晶体透射谱,用等效折射率n_eff介质概念来描述光在此晶体中的传播。因Bloch波共振和受激辐射以及光子隧道贯穿极大地增强了自发辐射的几率,使能量被高度局域,进而大大增强了它们的透射率,当波源中心频率发生微小变化时,而导致波峰位置有大的移动,以此得到晶体的光子流可控特性来优化光子晶体的传输性能。更多还原

【Abstract】 As a new kind of developed fibers with many particular and useful characteristics, the photonic crystal fibers （PCFs） have recently attracted a great deal of interest both in theory and experiments. It’s very difficult to give a qualitative or analytical analysis for a PCF due to its complicate structure,so numerical simulation is often necessary when one needs to analyze or design the characteristics of PCFs. The main contents are:1) In my thesis, we emphasize discussing solid core photonic crystal fibers’ dispersion of properties. First, take the C_6v total internal reflection photonic crystal fibers for example, we found the dispersion’s disciplinarian by change the structural parameters. Second, based on many forerunners’ experience, by changing hollow core photonic crystal’s shape, for example: triangle, hexagon, rectangle etc, which can find out the variety of dispersion. And localized fields of doped photonic crystal fibers, we know its effect on the dispersion. Last, according to above mentioned some conclusions, we may design more well special photonic crystal fibers.2) A full vector model is used to analyze the transmission properties of hexagonal air core photonic. By field pattern and curve, the internal regularity of energy flow, effective and effective core area is described directly. It is concentrated on how effective index, effective area and energy flow distribution can get the maximum by altering the structure parameters of the fiber and borehole spacing and proper parameters.3) Transmission spectrum from triangular structure PCs with equivalent negative index of refraction is studied with FDTD method in the paper, and the concept of equivalent index (n_eff) of refraction material is used to describe the optical transmission from such PCs. Because probability of spontaneous radiation is enhanced extremely by Bloch wave resonance stimulated radiation and photon tunneling, which makes energy highly location limited and the greatly strengthen their transmittance, the unilateral conduction of light and all-optical switching character are gained.更多还原