光学仪器, 2018, 40 (4): 47, 网络出版: 2018-09-15
太赫兹金属光子晶体结构研究
Study of terahertz metallic photonic crystals
时域有限差分 金属光子晶体 光子能带 表面波 角度依赖性 finite difference time domain metallic photonic crystal photonic band surface waves angular dependence
摘要
鉴于金属光子晶体结构在滤波、极化、传感、成像等领域的重要作用, 研究了基于三角形晶格的金属光子晶体的超常透射、光子能带和表面波特性。采用三维时域有限差分法对金属光子晶体结构建模, 同时解释超常透射机理;推导和讨论光子能带沿着ΓK和ΓM晶格方向的能带图, 分析不同的表面波特征, 并解释非对称入射下观察到的三角形的两个晶格方向模式分裂效应;建立了描述这种模式分裂效应的精确的表面模式谐振频率公式, 并对金属光子晶体的色散进行了定量分析。研究结果可为太赫兹功能器件的研究提供参考。
Abstract
Owing to its wide applications in the fields of filtering, polarization property, sensing, and imaging, the metallic photonic crystal structure has become the most attractive research field in the past decade.Hence the questions on how to design and analyze the photonic band structure and surface wave modes in the metallic photonic crystals have become important in the development of such frequency selective surfaces devices.Here, based on our previous work, we present a short review to describe the mode characteristics of metallic photonic crystal with a triangular lattice, including extraordinary transmission, photonic bands, and the interaction between surface wave and metallic photonic crystals.Firstly, we used 3-dimension finite difference time domain method with perfectly matched layer to provide a generation process of the surface wave in order to explain the transmittance mechanism of metallic photonic crystal.Then, we derived and discussed photonic band diagrams for two lattice directions and analyzed the characteristics of surface wave along the planar surface of metallic photonic crystal.Splitting of resonance modes had also been observed by varying the incident polar angle along ΓK and ΓM lattice directions, which is due to the off-normal incidence.In addition, exact formulas of angular-dependent resonance frequencies were derived to quantitatively analysis the dispersion of metallic photonic crystal.Such angle dependence results drive the development of related applications and can be used to analyze and design devices based on metallic photonic crystal as well as its attractive application prospects.
陈麟, 杨冰洋, 雍有, 杨涵, 杨洁, 许恩豪. 太赫兹金属光子晶体结构研究[J]. 光学仪器, 2018, 40(4): 47. CHEN Lin, YANG Bingyang, YONG You, YANG Han, YANG Jie, XU Enhao. Study of terahertz metallic photonic crystals[J]. Optical Instruments, 2018, 40(4): 47.