光子晶体环形腔的四波长THz滤波器

Four-wavelength THz filter based on photonic crystal ring resonator

提出一种基于光子晶体环形腔的四波长THz滤波器,该滤波器在光子晶体结构中引入两个环形腔,且环形腔内部各增加一个正方形介质柱,四周各引入一个散射介质柱。应用基于时域有限差分法(FDTD)的Rsoft软件进行仿真分析,结果表明通过对内部正方形介质柱的边长、散射介质柱半径以及耦合介质柱半径等结构参数的调节,可以滤出74.813,76.98,78.168和78.883μm四个太赫兹波长。该滤波器性能优良,透过率高、Q值高、信道隔离度大,对于THz技术应用具有重要意义。

A four-wavelength THz filter based on photonic crystal ring resonators is proposed in the paper, which contains a square dielectric column in each of the two ring resonators and around the column there are four scattering dielectric cylinders. An FDTD-based Rsoft software is used for simulation and the results show that four THz wavelengths （74. 813, 76. 980, 78. 168 and 78. 883 μm） can be filtered out by changing the structure parameters such as the side length of the internal square dielectric column, scattering media cylinder radius and the coupling medium cylinder radius. The performance of this filter is excellent because of its high transmittance, high Q value and large channel isolation, in which case this filter has important meaning for THz technology application.