【作者】 杨鹏飞；

【导师】 姚建铨；

【作者基本信息】 天津大学 ， 光电子技术， 2011， 博士

【摘要】 人类进行通信的历史已很悠久。早在远古时期,人们就通过简单的语言、壁画等方式交换信息。到了近现代,借助科学技术的不断改革与进步,通信技术也得以迅猛发展。但是随着生产的发展,大规模改造自然的需要以及人们生产和生活的日益社会化和国际话,所需要传递的信息数量几乎每周,每月都呈现创纪录的天文数字。现在已建立的有线和无线通信系统在通信容量和通信效率方面正日益显露出局限性。THz波介于微波与远红外光之间,处于电子学向光子学的过渡领域,它集微波通信与光通信的优点于一体,同时在传输等方面也表现出独有的特性。THz技术可广泛应用于雷达、遥感、国土安全与反恐、高保密的数据通讯与传输、大气与环境监测、实时生物信息提取以及医学诊断等领域。因此,THz研究对国民经济和国家安全有重大的应用价值。同时,由于太赫兹频段属于空白频段,现在没有分配执照,可望提供固网和移动网的高服务质量(QoS)宽带多媒体10Gb/s左右的无线业务。电子学和光子学的发展,极大地促进了数据处理和传输能力。随着科学技术的发展,高度集成化成为主流的发展方向。传统介质集成光学器件由于衍射极限的限制,在小型化、集成化方面遇到瓶颈。表面等离子体是强烈束缚在金属和电介质材料界面上的一种特殊的电磁场形式。表面等离子体波导有着在亚波长尺度内对光的传导能力。通过适当的波导结构设计,就可以突破衍射极限的限制。因此,人们开始关注表面等离子波及其器件,希望能够在微纳米级的器件和光回路中得到广泛应用。本文主要内容和创新点如下:1.详细介绍了国内外太赫兹通信的研究情况;以太赫兹通信系统的整体框架,介绍和分析了太赫兹通信的一些关键技术和最新研究成果;对太赫兹的技术发展趋势和应用前景做了展望。2.从麦克斯韦方程出发,介绍了表面等离子激元共振基本原理,特性以及激发方式。3.在传统狭缝等离子波导的基础上提出了异质双圆柱形纳米线等离子波导的结构设计。该结构主体由GaAs以及Ag纳米线组成,通过结构参数的调整,最小可以将波导中的传输模限制在只有衍射极限1/600大小的模场面积中。与此同时,通过结构尺寸的调整我们可以使传输距离增加到mm的范围内。4.通过在金属槽型等离子波导中引入高折射率介质材料,可将传输模能量耦合限制在高折射率材料中,以减少金属损耗。该波导结构设计可将槽型波导所支持的传输距离延长2倍,并且通过调整结构上方涂层折射率可以实现对传输距离的控制。5.利用麦理论讨论了纳米金属颗粒以及纳米金属壳颗粒的表面等离子光学特性,结合等离子增益补偿原理,提出了具有增益补偿的的金纳米壳等离子激光颗粒的设计,分别对比分析了在包层以及同时在包层和芯中加入增益介质的情况,发现在壳两侧的包层及芯中同时加入增益介质更有利于受激辐射的产生。同时通过调整结构参数,其工作波长可实现在600nm-1000nm区间可调。更多还原

【Abstract】 The history of human communication has been very long. Back to ancient times, people with simple language, murals, etc. to exchange information. To the modern, with the continuing reform of science and technology,communication technology is in a rapid development. The magnitude of information is changing greatly because of the following reasons, such as the development of production, the requirement of massive nature remodeling and the increasing socialization and internationalization of modern production and living. The limitations of existing wire and wireless communications systems in capacity and efficiency are emerging increasingly.Terahertz electromagnetic radiation is one of the last remaining unexplored regions of the electromagnetic spectrum. The THz region, occupying a large portion of the electromagnetic spectrum between the infrared and microwave bands. It has the following features: higher data transfer rate (about 10Gb/s), good direction, higher safety, lower scatter, higher transmittance and so on. THz wave technology can be applied to various scientific fields such as radar, remote sensing, safety inspection, antiterrorism, secure communication, atmospheric/environmental monitoring, real-time biology extraction, medical diagnosis and so on. Now Terahertz technology is becoming a research focus in communication field in developed countriesHigh level of integration is the development direction of modern science and technology. The traditional medium integrated optic components have bottleneck in miniaturization and integration because of the limit of diffraction. Surface plasmons (SPs) are a special kind of electromagnetic field, which are strongly confined to the interface of metal and dielectric materials. Plasmon waveguides can guide optical field in sub wavelength scale, even can break through the diffraction limit. Now it has been the focus of research and hoped to be used in nanometer components and circuit.The main contents and key creation points of this dissertation are as follows:1. We briefly introduced the research situation of terahertz communication domestic and overseas. Analyzed the overall framework of terahertz communication . Gave a review of some key technology in THz communication , and displayed some latest research achievement. We also give a outlook on the developing trend and application prospect of THz wave technology.2. Gave a detailed introduction to surface plasmon and it’s characters from solving the Maxwell equations3. We proposed a design of the surface plasmon waveguide, called hybrid nanoline plasmonic waveguide. It consists of a dielectric nanowire separated from a metal nanoline by a nanoscale dielectric gap. The coupling between the plasmonic and waveguide modes across the gap allows effective sub wavelength transmission in non-metallic regions. In this way the hybrid mode can be strongly confined to sizes as small as 1/600 of the area of a diffraction limited spot4. Introduced a high refractive index dielectric core into the channel plasmon waveguide which will allow us to confine most of the energy within it, because of the low loss constant compare to metal, the mode propagation length of our structure can be at least 2 times longer than that of the traditional channel waveguide.5. We studied the optical properties of the metal nanoparticle, metal nanoparticle with dielectric shell, and the metal nanoshell respectively with Mie theory. Based on the theory of stimulated emission of surface Plasmon assisted by gain materials, we give a feasible solution that add the gain materials to both dielectric materials in and out of the metal shell, so the metal nanoshell particle can give a stimulated emission, and the emission wavelength can be designed from 600nm to 1000nm by change the shell size and thickness.更多还原