【作者】 刘亚楠；

【导师】 方家熊； 李炎；

【作者基本信息】 山东大学 ， 电子与通信工程（专业学位）， 2019， 硕士

【摘要】 光学色散一直以来都是光学领域中非常具有研究价值的一部分,它在光信息处理、光谱分析等方面具有重要作用。由于传统光学元件是通过光束经过元件时产生的连续相位延迟的积累来实现对于光束波前调制的,这使其主要依赖于材料本身的性质或形状轮廓。受限于天然材料的性质局限,传统光学元件通常存在尺寸较大、难以集成等问题,无法满足人们追求小型化、集成化的应用要求。近年来,超构表面因其具备的强大的光场操控能力在各国引发了研究热潮。超构表面是一种亚波长人工层状材料,可以看做是超构材料的二维对应,与超构材料相比,具有更易制备、损耗更小等优点。超构表面一般具有天然材料所不具备超常的物理特性,可以通过亚波长的微细结构实现对电磁波相位、振幅、极化方式等多种特性的灵活调控,它的出现为人们对光场的操控提供了新的研究思路。与传统光学元件相比,超构表面具有轻薄、易集成等优势,在光通信、光学传感、聚焦/成像器件等技术领域具有非常广泛的应用前景。本文主要针对光学超构表面结构的多波长色散特性展开相关研究工作,探索利用超构表面实现近红外波段(1450nm-1650nm)高效率的色散分光的设计方案。主要工作内容如下:1.针对传统光学色散元件的存在的问题,结合超构表面的优势,根据广义斯涅尔定律及超构表面工作原理,设计了一种工作在近红外波段(1450nm-1650nm)基于V形天线的多波长色散超构表面,使用FDTD Solutions数值仿真软件对所设计的超构表面进行了仿真计算和结果分析,证明了其在特定波段的分光能力,并且为提高工作效率对其进行了几个不同方向的优化尝试,对仿真结果进行了分析;2.根据V形天线多波长色散超构表面存在的问题,设计了一种结构更加简单的、效率更高的梯形天线多波长色散超构表面。与基于V形天线的超构表面相比,构成梯形超构表面的天线阵列每个周期单元仅含有一个天线结构,周期长度缩短,不同波长入射光的色散角度差有所增大,且其结构更加简单、更易制备。该超构表面采用了天线-绝缘体-金属膜的结构,通过数值仿真证明了利用超构表面可以实现近红外波段(1450nm-1650nm)较为高效的色散分光。更多还原

【Abstract】 Optical dispersion has always been a very valuable part of the optical field,and it plays an important role in optical information processing and spectral analysis.The conventional optical devices achieve wavefront modulation of the beam by accumulating a continuous phase delay generated by the beam passing through the component,which mainly depends on the nature or shape profile of the material itself,and is limited by the nature of the natural material.Therefore,the conventional optical devices usually have problems such as large size and difficulty in integration,and cannot meet the application requirements of miniaturization and integration.In recent years,the metasurface has received widespread attention due to its powerful light field control capability.It is a subwavelength artificial layered material.which can be reigarded as a two-dimensional correspondence of the metamaterial.Compared with metamaterial,metasurface has the advantages of easier preparation and smaller loss.Metasurface has the extraordinary physical properties that natural materials do not have.It can realize the flexibility of various characteristics such as electromagnetic wave phase,amplitude and polarization by sub-wavelength microstructure.Regulation.,Its appearance provides a new research idea for people to control the light field.Compared with traditional optical components,metasurface has the advantages of lightness,easy integration,low loss.etc.,and has a very wide application prospect in the fields of optical communication,optical sensing,focusing and imagine devices.In this paper,we focus on the mufti-wavelength dispersion characteristics of metasurface,and explore the application of high-efficiency spectral splitting in the near-infrared band(1450nm-1650nm).The main contents are as follows:1.Aiming at the existing problems of traditional optical dispersion elements,according to the general Snell’s law and metasurface working principle.We designed a multi-wavelength dispersion metasurface based on V-shaped antennas working in the near-infr-ared band(1450nm-1650nm).We used FDTD Solutions to carry out simulation test and result analysis on the designed metasurface,which proved its spectral splitting ability in a specific band.And in order to improve work efficiency.we conducted several optimization experiments in different directions and analyzed the test results.2.According to the problem of multi-wavelength dispersion metasurface based on V-shaped antennas.we designed a simpler multi-wavelength dispersion metasurface based on trapezoidal antennas.Compared with the metasurface based on the V-shaped antenna.the antenna array constituting the trapezoidal metasurface contains only one antenna unit per cycle unit,the period length is shortened,the dispersion angle difference of incident light of different wavelengths is increased,and the structure is simpler and easier to prepare.The metasurface adopts the structure of antenna-insulator-metal film.We have proved through simulation experiments that the metasurface can achieve more efficient spectral splitting in the near-infrared band(1450nm-1650nm).更多还原