中文摘要：

采用可以减小纤芯面积的小气孔设计方案巧妙设计并成功拉制了一根高非线性的单零色散微结构光纤.利用有限元法模拟并计算得到了该光纤的基模有效折射率、色散系数和非线性系数等基本属性随波长的变化关系,然后利用四波混频的有效相位失配方程模拟了其相位失配曲线.模拟表明,在该光纤中可以同时发生两组四波混频.在位于微结构光纤的正常色散区的0.800,0.810和0.820μm三个波长处,分别采用不同的功率抽运,在实验上都非常明显地观察到了分列于抽运波长两侧的四个增益波带的产生.经与相位失配曲线比较,发现它们满足相位匹配条件,从而证明了两组四波混频过程的同时发生.实验结果与理论预言符合得很好.发生在正常色散区的四波混频效应的产生可归结于负的四阶色散对相位匹配过程的贡献.本文研究可对微结构光纤的结构设计和基于四波混频的多波长转移技术的发展提供经验与借鉴,同时也对非常见波段激光器和宽带光源的开发具有参考意义.

英文摘要：

A highly nonlinear microstructured fiber with single-zero-dispersion wavelength is designed and drawn by reducing the core area in order to observe two groups of four-wave mixing processes by a single pump. The foundational material of the fiber is silica and its cladding is comprised of seven-layer air holes. The air holes are arranged in a hexagonal lattice and the lattice pitch is Λ = 2.5 μm. The radius of each of the air holes is r = 1.03 μm. There is just one zero-dispersion wavelength in our considerable wavelength range for the microstructured fiber and the corresponding wavelength λD is nearly 0.85 μm（λD =0.85 μm）. The basic properties of the fiber including effective refractive index,dispersion coefficient, and nonlinear coefficient are calculated by the finite element method. The effective mode area is 4.4 μm^2 and the nonlinear coefficient is 0.057 m^-1·W^-1 for the foundation mode near the wavelength of 0.8 μm, and the nonlinear coefficient reaches 0.053 m^-1·W^-1 near the zero dispersion wavelength of 0.85 μm. In short, the optical fiber has a stable and high nonlinear coefficient in the whole experimental band（0.80–0.83 μm）, which provides an important guarantee for the occurrence of four-wave mixing double parameter gain process. In addition, the phase mismatch curve is simulated by using the four-wave mixing phase mismatch formulation. Numerical simulation shows that two sets of four-wave mixing processes can occur in the designed fiber. At the normal dispersion wavelengths of 0.800, 0.810 and 0.820 μm with different powers, the experimental result shows a significant feature of four gain wavebands located at both sides of the pump wavelength. By comparing experimental data with the phase mismatch curve, we find that the band generation meets four-wave mixing phase matching condition, thus, the simultaneous occurrence of two groups of fourwave mixing processes observed in the experiment is explained in theory. The experimental results are consistent well with the theoretica