材料色散对全固态带隙光纤带内色散的影响

摘要

全固态光子带隙光纤已开始用于产生超连续谱,其带隙效应可以控制超连续谱的范围,但是带内的色散特性对于超连续谱的产生有着重要的影响.采用平面波法计算了同一带隙光纤不同阶带隙内的色散曲线和不同带隙光纤同阶带隙内的色散曲线,零色散波长在带内相对位置与带隙位置密切相关,在长波长区域,零色散点位于带隙的短波边;在短波区域,零色散点位于带隙的长波边.通过对波导色散和材料色散的计算发现,全固态带隙光纤的材料色散影响了零色散点在带隙内的相对位置.%All-solid photonic bandgap fibers have being used for supercontinuum generation. The spectral rang of supercontinuum is controllable with the use of bandgap. But the dispersion has significant effect on supercontinuum generation. In different bandgaps of the same photonic bandgap fiber and in the same order bendgaps of different photonic bendgap fibers, the group velocity dispersions were calculated with plane-wave methods. The results indicate that the relative position of the zero dispersion wavelength in the bandgap strongly depends on the location of the conesponding bandgap. Zero dispersion wavelength is in the proximity of the short wavelength edge d bandgap in long wavelength region. However, it is located near the long wavelength edge of bandgap in short wavelength region.From the calculated waveguide dispersion and material dispersion, it can be found that it is material dispersion that affects the relative position of zero dispersion wavelength in bandgap.