中国激光, 2011, 38 (s1): s111005, 网络出版: 2011-11-21
二维金属线网格结构的太赫兹滤波特性仿真研究
Numerical Simulation of Filtering Characteristics of Two-Dimensional Metallic Grid in Terahertz Band
摘要
基于时域有限差分(FDTD)法对金属井字形栅网、互补的方块阵列和二者叠加而成的十字叉丝孔阵列3种类型的二维金属线网格结构在太赫兹波段的滤波特性进行了数值分析。研究发现,金属井字形栅网结构实现了高通滤波的功能,方块阵列结构实现了低通滤波的功能,十字叉丝孔阵列结构则实现了带通滤波的功能。模拟结果表明,随着周期的增大,井字形栅网以及其互补方块阵列的截止频率向低频扩展,叠加而成的十字叉丝孔阵列允许透过的中心频率也随着周期的增大向低频移动。另外,以十字叉丝孔阵列结构为例的多层金属网格结构仿真结果显示,当层与层之间的间隔为20 μm,层数多于5层之后,其上升沿和下降沿都变得十分陡峭,层数的增加可以大大提高结构的滤波性能。
Abstract
Based on finite difference time domain (FDTD) method, the numerical simulation of filtering characteristics of the two dimensional metal grid which include the well-shaped grid, the array of complementary square metallic pill and the cross wire-hole array are carried out. The results show that the well-shaped metal grid structure achieves a high-pass of filter function, the array of square metallic pill achieves a low-pass of filter function, and the cross wire-hole array structure achieves a band-pass of filter function. Simulation results show that, with the increasing of the period the cut-off frequency of high-pass filter and low-pass filter move to low-frequency, and the center frequency allowed by the cross wire-hole array similarly moves to the low-frequency. The result of the multi-layer structure of the cross wire-hole array shows that, the rising edge and the falling edge become very steep when the spacing between layers is 20 μm and the more than 5 layers are used which greatly improved the filtering performance.
刘立明, 赵国忠, 魏波. 二维金属线网格结构的太赫兹滤波特性仿真研究[J]. 中国激光, 2011, 38(s1): s111005. Liu Liming, Zhao Guozhong, Wei Bo. Numerical Simulation of Filtering Characteristics of Two-Dimensional Metallic Grid in Terahertz Band[J]. Chinese Journal of Lasers, 2011, 38(s1): s111005.