基于介电函数实验值拟合对一维光子晶体能带结构的分析与讨论

The analysis of 1D photonic crystal band structure based on the dielectric dispersion fitting

使用与在宽波段范围内TiO2,SiO2介电函数相似的指数型函数,利用数值拟合方法,给出了与实验介电函数值完全吻合的色散关系;将其直接应用于平面波展开法,计算分析了一维TiO2/SiO2色散光子晶体能带结构.与常规平面波展开法的计算结果对照发现,由两种方法分别计算得到的能带结构中均有两个较宽的光子带隙,但两者的带宽和位置均有所不同,且改进后的计算结果中未出现中间的一个窄带隙.分析认为,改进后的平面波展开法计算出的能带结构似更符合实际.

A modified plane wave expansion method based on the dispersion fitting of TiO2 and SiO2 for calculating the band structure of one dimensional（1D） TiO2/SiO2 photonic crystal is presented. Compared to band structure calculated by conventional plane wave expansion method, the dielectric dispersion of TiO2 and SiO2 has effect on the calculation of the band structure, and the present method is more effective to calculate the band structure for 1D TiO2/SiO2 photonic crystal.