基于InSb可调谐太赫兹表面等离子体吸收器的研究

发布时间：2018-03-01 21:38

本文关键词： 太赫兹吸收器多波长可调谐耦合电磁感应透明法布里-珀罗　出处：《北京交通大学》2017年博士论文　论文类型：学位论文

【摘要】：太赫兹科学技术在最近十年得到了迅猛的发展,而且越来越受到相关研究人员的重视,这是由于它在如生物科学,医学成像,安全和空间科学,传感等诸多领域有着重要的应用。鉴于太赫兹科学技术潜在的应用价值和广阔的发展前景,吸引了世界各国大量科研人员的研究兴趣,一系列太赫兹器件得到了飞速的发展。例如发射器,调制器,滤波器,检测器和吸收器等等,这些器件的不断改进使得太赫兹系统的性能得到不断的优化。在这些器件中,太赫兹吸收器促进了太赫兹探测器、热发射器、传感器和室温下隐身操作技术的进一步发展。在过去的十年中,基于平面超材料的太赫兹吸收器得到了快速的发展,此类太赫兹吸收器表现出了很多优异的性能,例如偏振不敏感、全角度、双波长、三波长、超窄带和宽带吸收等等。不幸的是,这些吸收器的吸收峰很难调谐,除非改变其几何参数,对于制定好的器件来说,反复修改其几何尺寸显得十分笨拙,另外这些所谓的超材料都是通过金属和介质组合形成的,其排列还有一定的规则,有时候想要找到合适的金属-介质组成的超材料还相当困难,那么自然界中是否存在能吸收太赫兹波,且介电常数可调谐的材料呢?答案是肯定的。本文主要设计并研究了基于半导体InSb太赫兹波段的多种可调谐太赫兹吸收器,着重利用电磁感应透明原理和明暗谐振腔的强耦合导致原始共振频率发生分裂的物理现象设计了可调谐太赫兹多波长吸收器。论文主要创新成果如下:1.对三种(金属、石墨烯、半导体)可以支持SPP波的材料进行了对比,并分别利用三种材料设计了若干性能优异的微纳光子器件。2.设计了基于对称T型InSb阵列的单波长太赫兹吸收器,吸收效率高达99.3%。另外吸收频率的位置可以通过温度来调控。3.分析了 InSb-Air-InSb波导中的电磁感应透明(EIT)现象,并利用该原理设计了多波长太赫兹吸收器,且当两FP腔距离满足特定条件时,双波长太赫兹吸收器可以演变为宽带太赫兹吸收器。4.研究了明暗谐振腔之间的强耦合可以使原始共振频率可以分裂为两个超模共振频率,基于此原理设计并研究了基于InSb的可调多波长太赫兹吸收器。5.分别利用FP腔的级联和FP腔的高阶谐振设计了宽带(吸收带宽约0.2THz)太赫兹吸收器和窄带(吸收半全带宽约0.018THz)太赫兹吸收器。由于InSb的介电常数的温敏特性,本文中所设计的太赫兹吸收器的吸收频率的位置均可以通过温度来调节。本文的研究工作在军事领域、生物医疗、能源领域等方面有潜在的应用价值。
[Abstract]:Terahertz science and technology has developed rapidly in the last decade, and has received increasing attention from relevant researchers because of its role in biological science, medical imaging, safety and space science. Sensing and many other fields have important applications. In view of the potential application value and broad development prospects of terahertz science and technology, it has attracted the research interest of a large number of researchers from all over the world. A series of terahertz devices have been rapidly developed, such as transmitters, modulators, filters, detectors, absorbers, and so on. The continuous improvement of these devices makes the performance of terahertz systems continuously optimized. Terahertz absorbers have contributed to the further development of terahertz detectors, thermal emitters, sensors and stealth techniques at room temperature. In the past decade, terahertz absorbers based on planar supermaterials have developed rapidly. These THz absorbers exhibit many excellent properties, such as polarization insensitivity, full angle, dual wavelength, three wavelength, ultra-narrow band and broadband absorption, etc. Unfortunately, the absorption peaks of these absorbers are difficult to tune. Unless the geometric parameters are changed, it is very awkward for a device to modify its geometric size repeatedly, and these so-called metamaterials are formed from a combination of metals and media, and there are some rules in their arrangement. Sometimes it is difficult to find a metallic-dielectric supermaterial, so is there a material in nature that absorbs terahertz waves and tunable dielectric constants? In this paper, we design and study a variety of tunable THz absorbers based on semiconductor InSb terahertz band. The tunable terahertz multiwavelength absorber is designed based on the principle of electromagnetic induction transparency and the physical phenomenon that the strong coupling of the light and dark resonators leads to the splitting of the original resonance frequency. The main innovative achievements of this paper are as follows: 1. For three kinds of (metal, graphene, graphene), a tunable terahertz multiwavelength absorber is designed. Semiconductor) can support SPP wave materials are compared, and several excellent micro-nano photonic devices are designed using three kinds of materials. A single-wavelength terahertz absorber based on symmetric T type InSb array is designed. The absorption efficiency is as high as 99.3. In addition, the position of absorption frequency can be adjusted by temperature. The phenomenon of electromagnetically induced transparency in InSb-Air-InSb waveguides is analyzed, and a multi-wavelength terahertz absorber is designed using this principle. When the distance between two FP cavities satisfies certain conditions, the dual-wavelength terahertz absorber can evolve into wideband terahertz absorber .4.The strong coupling between light-dark resonators can split the original resonant frequency into two supermode resonant frequencies. The tunable multiwavelength terahertz absorber based on InSb is designed and studied based on this principle. The broadband (absorption bandwidth about 0.2 THZ) terahertz absorber and narrow band (absorption half full) are designed by using the cascade of FP cavity and the high order resonance of FP cavity, respectively. Bandwidth about 0.018 THZ) terahertz absorber. Due to the temperature sensitivity of the dielectric constant of InSb, The position of the absorption frequency of the terahertz absorber designed in this paper can be adjusted by temperature. The research work in this paper has potential application value in military field, biomedical field, energy field and so on.
【学位授予单位】：北京交通大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：O441

【相似文献】