基于太赫兹超材料的电磁诱导透明研究

发布时间：2018-01-20 01:28

本文关键词： 超材料太赫兹电磁诱导透明宽频带谐振　出处：《北京交通大学》2017年硕士论文　论文类型：学位论文

【摘要】：超材料是一种具有人工结构阵列的材料,与天然材料相比有着独特的奇异物理性能。对这一性能加以有效控制,可进一步控制电磁波在这种材料中的传播特性。近年来,利用超材料提升太赫兹器件的性能成为研究人员关注的热点,涌现出基于超材料的太赫兹滤波器、吸波器、传感器、偏振片、调制器等新型器件。其中一个具有代表性的方面即为基于超材料模拟电磁诱导透明的研究。这种现象所表现出的卓越慢光性能,对于太赫兹开关、太赫兹调制器的发展有很大的促进作用。本文对基于超材料的电磁诱导透明结构进行设计,并对其性能参数进行仿真分析。主要研究内容为:1.提出一种基于石墨烯片以及开口谐振环实现太赫兹波段宽频带电磁诱导透明现象的主动式超材料结构。利用开口谐振环所产生的LC谐振作为暗模式,石墨烯材料产生的偶极等离子体谐振充当明模式,通过在该平面结构上增加暗模谐振器数量以增强谐振器间耦合进而拓宽频带。通过对该结构的透射光谱及电场分布进行仿真分析,揭示了通过增强电磁耦合展宽频带的特性,验证了基于调节明模原子的谐振频率进行主动控制电磁诱导透明窗口的可行性。2.运用三原子系统理论及宽频带理论设计了基于超材料的太赫兹双模宽频带电磁诱导透明结构,透明窗口带宽分别为0.30 THz和0.24 THz。利用仿真所得透射光谱以及电场分布分别对明模谐振器、暗模谐振器、准暗模谐振器进行单独谐振及组合产生电磁诱导透明现象的作用机理进行分析,结果表明通过利用明模谐振器与暗模谐振器、明模谐振器与准暗模谐振器交替耦合所组成的结构可以呈现出双模电磁诱导透明的特性。进一步对影响多层结构的宽频带特性、几何参数及电介质层因素进行了分析。
[Abstract]:Metamaterial is a kind of material with artificial structure array, which has unique physical properties compared with natural materials. In recent years, the use of metamaterials to improve the performance of terahertz devices has become the focus of attention of researchers, the emergence of terahertz filters based on metamaterials. Novel devices such as absorbers, sensors, polarizers, modulators and so on. One of the representative aspects is the study of electromagnetic induced transparency based on metamaterials. This phenomenon shows excellent slow light performance. The development of terahertz modulator plays a very important role in the development of terahertz switch. The electromagnetic induced transparent structure based on metamaterials is designed in this paper. The performance parameters are simulated and analyzed. The main research contents are as follows:. 1. An active metamaterial structure based on graphene sheet and open resonant ring is proposed to realize the wide band electromagnetic induced transparency in terahertz band. The LC resonance generated by the open resonant ring is used as dark mode. The dipole plasma resonance produced by graphene materials acts as an open mode. By increasing the number of dark mode resonators in the plane structure to enhance the coupling between resonators and broaden the frequency band, the transmission spectrum and electric field distribution of the structure are simulated and analyzed. The characteristics of broadening the frequency band by enhancing electromagnetic coupling are disclosed. The feasibility of active control of electromagnetic induced transparent window based on adjusting the resonant frequency of open-mode atom is verified. 2. The terahertz dual-mode broadband electricity based on supermaterial is designed by using the theory of Sanyuan subsystem and broadband theory. Magnetically induced transparent structure. The transparent window bandwidth is 0. 30 THz and 0. 24 THZ respectively. The transmission spectrum and electric field distribution obtained by simulation are applied to the open mode resonator and dark mode resonator respectively. The mechanism of the quasi-dark mode resonator and the electromagnetic induced transparency caused by the combination are analyzed. The results show that the open mode resonator and the dark mode resonator are used. The structure composed of alternating coupling of open mode resonator and quasi dark mode resonator can exhibit the characteristics of double mode electromagnetic induced transparency and further influence the broadband characteristics of multilayer structure. Geometric parameters and dielectric layer factors are analyzed.
【学位授予单位】：北京交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB34;O441

【参考文献】