太赫兹波段纳米颗粒的表面增强拉曼散射效应

发布时间：2018-12-30 13:43

【摘要】：太赫兹波谱处于以经典理论为基础的电子学和以量子理论为基础的光子学之间过渡区域,从而它的性质就呈现出一系列特殊性,可以应用在医学、成像、通信和天文等诸多领域。尤其是在生物大分子探测上有着突出的应用优势,与表面增强拉曼散射(Surface-enhanced Raman Scattering,SERS)技术在生物大分子检测方面有着很多的共同点。将太赫兹波与SERS结合起来形成一种基于SERS的太赫兹探测技术,在大分子检测过程中有着明显的优势,不仅可以描述大分子的分子结构而且也可以对其浓度进行检测。以SERS基底组成部分的金属和半导体纳米结构的表面电磁增强效果作为论文命题的研究重点,使用时域有限差分(Finite Difference Time Domain,FDTD)方法对金属和半导体纳米结构的表面电磁增强效果进行了数值计算模拟。本论文对太赫兹技术与SERS技术相结合的命题进行了以下研究:1)SERS及其拉曼散射基础理论。研究分析了拉曼散射的形成原理,SERS的增强机理。针对论文命题对太赫兹波技术和SERS技术相结合的基础模型,以金属纳米颗粒结构为例,对SERS基底的增强机理进行了分析。2)FDTD的原理分析及软件FDTD Solutions具体应用的设置研究。研究分析了描述电磁场的Maxwell方程组在时域的差分形式,对各个关键点进行了分析。介绍了以FDTD为基础的软件FDTD Solutions的仿真设置。3)金属和半导体纳米颗粒在太赫兹波段的SERS效应研究。研究分析了金属和半导体纳米颗粒结构在太赫兹波段的近场电磁增强分布情况,进而得到SERS增强因子,从基础上阐明了太赫兹波技术与SERS技术相结合的原理。实验中对金和锑化铟纳米颗粒“热点”处的近场电磁增强效果进行了计算仿真,得到了“热点”处的SERS增强因子分别可以达到106和109。
[Abstract]:The terahertz spectrum is in the transition region between electronics based on classical theory and photonics based on quantum theory, so its properties show a series of particularities, which can be used in medicine and imaging. Communications and astronomy and many other fields. Especially in the detection of biological macromolecules, there are many common points with surface enhanced Raman scattering (Surface-enhanced Raman Scattering,SERS) technology in the detection of biological macromolecules. Combining terahertz wave with SERS to form a terahertz detection technology based on SERS, it has obvious advantages in the detection of macromolecules. It can not only describe the molecular structure of macromolecules but also detect their concentration. Based on the surface electromagnetic enhancement effect of metal and semiconductor nanostructures based on SERS substrate as the focus of the thesis, the finite-difference time-domain (Finite Difference Time Domain, is used. The surface electromagnetic enhancement effect of metal and semiconductor nanostructures was numerically simulated by FDTD method. In this thesis, the proposition of combining terahertz technique with SERS technique is studied as follows: 1) SERS and its Raman scattering theory. The formation principle of Raman scattering and the enhancement mechanism of SERS are studied and analyzed. Aiming at the basic model of combining THz wave technology with SERS technology, the strengthening mechanism of SERS substrate is analyzed by taking the metal nanoparticles as an example. 2) the principle analysis of FDTD and the setting up of the application of software FDTD Solutions are studied. The difference form of Maxwell equations describing electromagnetic field in time domain is studied and the key points are analyzed. The simulation setup of FDTD Solutions software based on FDTD is introduced. 3) the SERS effect of metal and semiconductor nanoparticles in terahertz band is studied. The near field electromagnetic enhancement distribution of metal and semiconductor nanoparticles in terahertz band is studied and the SERS enhancement factor is obtained. The principle of combining terahertz wave technology with SERS technique is explained. In the experiment, the near field electromagnetic enhancement effect of gold and indium antimonide nanoparticles at "hot spot" is simulated, and the SERS enhancement factor at "hot spot" can reach 106 and 109 respectively.
【学位授予单位】：天津理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：O441.4

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