超窄带和梳状多通道光子晶体滤波器设计

Design of super narrow band and comb-shaped multi-channel photonic crystal filters

设计了一种因掺杂而具有超窄带滤波特性的光子晶体滤波器和一种复周期结构的梳状多通道光子晶体滤波器。在两种均匀介质交替分布的周期结构中间插入一层折射率不同的介质膜后,通过传输矩阵法的数值计算,发现采用前后不对称的周期结构并调节参数,可以在1 550 nm处找到一个透射率接近100%的极窄的透过峰,因而可得到一种超窄带光子晶体滤波器。另外,在以高低两种折射率的介质交替分布,并以两种单独的单元周期合并组成一个复周期,然后进行周期重复构成的光子晶体中,利用通道数等于复周期数减1的规律,并配合各层厚度的调节,设计出在1 550 nm附近梳状8通道和16通道的光子晶体滤波器,各通道透过峰的透射率均接近100%,由此设计出一种梳状多通道光子晶体滤波器。

In this paper, two kinds of photonic crystals are designed. One is the super narrow band optical filter, the other is the comb-shaped multi-channel optical filter. Based on the transfer matrix method, after inserting one layer of heterogeneous medium into two different homogeneous mediums, a super narrow pass band with a 100 % transmitivity can be obtained near 1 550 nm by adopting a dissymmetric structure and adjusting parameters in this crystal. In the complex-period optical crystal integrated by mediums with two alternatively distributed high and low refractive indexes whose complex period is combined by two separate cell periods, by following the law that the channel number is calculated by subtracting one from the complex-period number, a comb - shaped 8 - channel and a comb - shaped 1 6 - channel photonic crystal optical filters are designed , and their transmitivities approach 100% around 1 550 nm.