本文選題：等離子體　切入點：納米結(jié)構(gòu)　出處：《安徽大學(xué)》2015年碩士論文

【摘要】：隨著科學(xué)技術(shù)和實驗技術(shù)的發(fā)展,納米結(jié)構(gòu)材料的可加工,納米結(jié)構(gòu)因其表面特有的表面等離激元特性而越來越受到人們的關(guān)注。尤其納米結(jié)構(gòu)的表面等離子體能反應(yīng)其光學(xué)特性。在外加激勵源情形下,金屬中的自由電子與空氣表面發(fā)生共振而引起表面等離激元(SPP)。而等離子體光學(xué)就是基于金屬納米結(jié)構(gòu)中傳導(dǎo)電子與電磁輻射交互作用而引起的一種低于波長尺度的近場光學(xué)增強效應(yīng)。在實際應(yīng)用中如太陽能電池,由于金屬特殊的光學(xué)特性,能夠在一定條件下激勵出表面等離子體激元引起共振現(xiàn)象,通過改變金屬薄膜厚度、周圍介質(zhì)和金屬的周期性結(jié)構(gòu)等參數(shù),都可以大幅度提高納米薄膜的電磁透射效率。在其他方面其應(yīng)用也越來越廣泛,例如在生物傳感器、近場顯微技術(shù)和表面局域和近場增強特性,超分辨成像以及納米級的光電器件制造等領(lǐng)域。本文的研究工作主要是圍繞基于表面等離子體共振,在不同的貴金屬納米結(jié)構(gòu)的表面產(chǎn)生的局域和非局域化光學(xué)特性。本文主要分為以下三個內(nèi)容：首先介紹研究的背景,并介紹了表面等離子體和納米結(jié)構(gòu)的光學(xué)特性參數(shù)等基本理論概念。其次主要介紹了計算貴金屬納米結(jié)構(gòu)光學(xué)特性的數(shù)值仿真算法,著重介紹了時域有限差分算法(FDTD)的基本原理和基本方法。引入了模擬貴金屬介電常數(shù)的幾種模型,通過采用Drude和Lorentz模型,對貴金屬的介電常數(shù)進行擬合。介紹了貴金屬納米結(jié)構(gòu)的局域(local)和非局域(nonlocal)的特性。結(jié)合FDTD算法,在不同介電常數(shù)模型下,得到了電場和磁場的具體差分公式,并利用后處理技術(shù)得出吸收截面、散射截面和消光截面。最后主要研究不同結(jié)構(gòu)下貴金屬納米結(jié)構(gòu)的local和nonlocal性質(zhì)。首先研究了不同厚度下的金屬薄膜的傳輸、反射和吸收特性；其次討論不同納米線結(jié)構(gòu)和柱納米線和三角形納米線之間耦合下的local和nonlocal特性；最后討論核殼模型下,不同尺寸和周圍介質(zhì)對貴金屬納米結(jié)構(gòu)消光截面的影響。
[Abstract]:With the development of science and technology and experimental technology, nanostructured materials can be machined. Nanostructures have attracted more and more attention because of their unique surface isophosphoric properties, especially the surface plasmas of nanostructures can reflect their optical properties. In the case of external excitation sources, the surface plasmas of nanostructures can reflect their optical properties. The resonance between free electrons in metal and air surface leads to the surface isotherm SPP. The plasma optics is based on the interaction between conducting electrons and electromagnetic radiation in metal nanostructures, which is a kind of lower wavelength scale caused by the interaction of electron conduction and electromagnetic radiation in metal nanostructures. In practical applications such as solar cells, Because of the special optical properties of metal, the surface plasmon excitation can induce resonance under certain conditions. By changing the thickness of the metal film, the periodic structure of the surrounding medium and the metal, and so on, Can greatly improve the electromagnetic transmission efficiency of nanocrystalline films, and are also increasingly used in other areas, such as biosensors, near-field microscopy and surface local and near-field enhancement properties, Super-resolution imaging and the fabrication of nano-scale optoelectronic devices. The research work in this paper is mainly based on surface plasmon resonance (SPR). The localized and nonlocalized optical properties on the surface of different noble metal nanostructures. This paper is divided into the following three parts: firstly, the background of the study is introduced. The basic theoretical concepts such as surface plasma and optical characteristic parameters of nanostructures are introduced. Secondly, numerical simulation algorithms for calculating optical properties of noble metal nanostructures are introduced. This paper introduces the basic principle and method of FDTD algorithm, introduces several models to simulate the dielectric constant of noble metals, and adopts Drude and Lorentz models. The dielectric constant of noble metals is fitted. The local and nonlocal properties of noble metal nanostructures are introduced. Based on the FDTD algorithm, the differential formulas of electric field and magnetic field are obtained under different dielectric constant models. Finally, the local and nonlocal properties of noble metal nanostructures under different structures are studied. Firstly, the transmission, reflection and absorption characteristics of metal films with different thickness are studied. Secondly, the characteristics of local and nonlocal under the coupling of different nanowires and column nanowires and triangular nanowires are discussed. Finally, the effects of different sizes and surrounding media on the extinction cross sections of noble metal nanostructures under the core-shell model are discussed.
【學(xué)位授予單位】：安徽大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號】：TB383.1
，

本文編號：1666722