1维光子晶体的能带结构分析

Analysis of energy band structure of 1-D photonic crystal

为了分析研究1维光子晶体的结构参量对其能带结构的影响,并把这种影响作用应用到滤波器的设计中,采用传输矩阵法、利用MATLAB仿真软件,对不同结构参量的1维光子晶体的能带结构进行了计算仿真,分别得到了不同周期数、不同介质层厚度、不同介质折射率的1维光子晶体的能带分布图,进一步分析比较,得出了1维光子晶体的结构参量对其能带结构的影响。结果表明,较大的周期数可以使1维光子晶体的禁带边缘更加陡峭,通带透射性增强,能带分布更加分明;介质层厚度可以调节光子晶体的能带分布情况及能带宽度;介质折射率比值可以改变禁带宽度,禁带宽度随介质折射率比值的增大而增大。这些结果对宽带带阻滤波器的设计是有帮助的。

In order to analyze effect of structure parameters of 1-D photonic crystal on energy band structure systematically and apply the result in filter design,transmission matrix method was used. Different energy band structures of photonic crystals of different structural parameters were calculated by MALTAB simulation software. Energy band distributions of 1-D photonic crystal with different cycles,different dielectric layer thickness and different media refractive indices were gotten. Through analysis and comparison,the effects of 1-D photonic crystal structure parameters on energy band structure were gotten. The results show that 1-D photonic crystal with larger cycle number has a steeper forbidden band-edge and higher transmission of pass band. In other word,the band distribution is more distinct. Energy distribution and energy width can be adjusted with dielectric layer thickness of photonic crystal. The width of band gap can be changed by the ratio of the refractive index of the medium. The width of band gap increases with the increase of the ratio of the refractive index of the medium. These results are helpful for the design of filters.