通过在全固态光子带隙光纤的纤芯中心处掺入高折射率锗,形成具有微结构芯的混合型导光的全固态光子晶体光纤。采用全矢量有限元法,对光纤的导光机制、模场、损耗、色散等特性进行了数值分析。结果表明,中心高折射率棒的半径从0开始增大,小于包层高折射率棒的半径时,基模有效折射率由靠近带隙下边界处开始向上移动,导光机制由带隙效应导光向混合型导光转变,损耗随之降低。在短波处,全内反射效应占主导,带隙边缘对损耗的影响减小,损耗曲线逐渐表现出随波长单调递增的特性。长波处,导光机制以带隙效应为主,损耗曲线整体下移。通过改变中心棒的大小,可以灵活调节光纤的零色散波长。研究结果表明,当中心棒的半径为0.5μm时,零色散波长向短波方向移动30nm;半径为1.2μm时,零色散波长向长波方向移动230nm,调整带宽达到260nm。 By incorporating high refractive index germanium at the core center of an all-solid photonic bandgap fiber, a hybrid lightguide all-solid photonic crystal fiber having a microstructure core is formed. The full vector finite element method is used to analyze the light guide mechanism, mode field, loss and dispersion of optical fiber. The results show that the radius of the center high refractive index rod increases from 0 to less than the radius of the cladding high refractive index rod, the effective refractive index of the fundamental mode begins to move upward from near the lower boundary of the bandgap, Light guide to the mixed-type light guide, loss will be reduced. At shortwave, the effect of total internal reflection is dominant, and the influence of the bandgap edge on the loss is reduced. The loss curve gradually shows monotonically increasing characteristics with the wavelength. Long-wave office, the light guide mechanism to band-gap effect, the overall loss curve down. By changing the size of the center bar, you can flexibly adjust the zero-dispersion wavelength of the fiber. The results show that when the central rod radius is 0.5μm, the zero-dispersion wavelength moves 30nm to the short-wavelength direction and the zero-dispersion wavelength moves 230nm to the long-wavelength direction and adjusts the bandwidth to 260nm when the radius is 1.2μm.