發(fā)布時(shí)間：2018-01-24 21:12

  本文關(guān)鍵詞： 表面等離激元 表面等離激元共振 高階表面等離激元共振 等離激元耦合　出處：《陜西師范大學(xué)》2015年碩士論文　論文類(lèi)型：學(xué)位論文

【摘要】：貴金屬的表面等離基元是指激發(fā)光與金屬表面附近的自由電子相互耦合所產(chǎn)生的沿著金屬的表面?zhèn)鞑サ囊环N電磁波,其理論自上世紀(jì)被提出之后獲得了越來(lái)越廣泛的關(guān)注。金屬納米顆粒的表面等離激元會(huì)隨著外部電磁場(chǎng)的改變而發(fā)生運(yùn)動(dòng),當(dāng)表面等離子體和外界電磁場(chǎng)的頻率一致時(shí)會(huì)發(fā)生共振,即為表面等離激元共振。金屬納米結(jié)構(gòu)的尺寸以及形貌都會(huì)對(duì)產(chǎn)生的表面等離激元共振特性構(gòu)成很大的影響,因此可以通過(guò)調(diào)整這些參數(shù)來(lái)構(gòu)建具有不同光學(xué)性質(zhì)的表面等離基元器件。由于表面等離激元器件可以突破光的衍射極限,從而實(shí)現(xiàn)比傳統(tǒng)光學(xué)器件更高的精度來(lái)操作光,所以在很多領(lǐng)域展示出了巨大的應(yīng)用前景,比如表面增強(qiáng)光譜、等離激元光波導(dǎo)、太陽(yáng)能電池、以及生物傳感器等。隨著各種理論研究的逐漸深入以及在微納尺度下對(duì)于金屬顆粒進(jìn)行加工的技術(shù)越來(lái)越成熟,對(duì)于不同的金屬納米結(jié)構(gòu)的表面等離基元性質(zhì)已經(jīng)成為了一項(xiàng)非常熱門(mén)的研究課題。這項(xiàng)研究也形成了一項(xiàng)迅猛發(fā)展的新興學(xué)科,即表面等離激元光子學(xué)。本文基于表面等離激元光子學(xué)的研究現(xiàn)狀,針對(duì)目前絕大多數(shù)的研究都集中在復(fù)雜的二維納米結(jié)構(gòu),提出了一種通過(guò)簡(jiǎn)單幾何結(jié)構(gòu)的耦合來(lái)產(chǎn)生比較復(fù)雜的表面等離激元特性的方法。本文主要分為三個(gè)部分,第一部分對(duì)目前主要使用的一些數(shù)值計(jì)算方法和本文中進(jìn)行數(shù)值計(jì)算的軟件進(jìn)行了介紹。第二部分對(duì)于一些基本的納米結(jié)構(gòu)和納米二聚體的表面等離激元特性進(jìn)行了介紹。第三部分設(shè)計(jì)了方框-方盤(pán)(SRD)復(fù)合結(jié)構(gòu)并研究了其表面等離激元光學(xué)特性并著重研究由于破壞對(duì)稱(chēng)性而產(chǎn)生的一些高階表面等離激元共振特性。各部分的內(nèi)容總體敘述如下；第一部分：介紹了目前常用的的一些數(shù)值計(jì)算方法,并且對(duì)于本文中使用的數(shù)值計(jì)算軟件做以簡(jiǎn)單介紹。其中主要介紹了時(shí)域有限差分(FDTD)法,離散偶極近似(DDA)法,以及有限元(FEM)法這三種常用的數(shù)值模擬算法。之后重點(diǎn)介紹了本文中所使用的利用了有限元法的COMSOL Multiphysics軟件。對(duì)于其中建模時(shí)需要注意的一些諸如邊界條件的設(shè)置、端口的設(shè)置和S參數(shù)的計(jì)算、初始值和背景場(chǎng)的設(shè)置等均做了詳細(xì)的解釋。第二部分：研究了一些比較基礎(chǔ)的結(jié)構(gòu)的表面等離激元特性。從最簡(jiǎn)單的納米球,納米盤(pán)以及納米環(huán)入手。隨后介紹了一些有關(guān)于納米顆粒二聚體的表面等離激元特性,其中分別包括了納米球二聚體和納米盤(pán)二聚體。介紹了一種在二聚體中產(chǎn)生暗等離激元共振模式的方法。第三部分：設(shè)計(jì)了一個(gè)方框-方盤(pán)(SRD)結(jié)構(gòu),通過(guò)改變SRD結(jié)構(gòu)中方盤(pán)和方框的相對(duì)位置來(lái)獲得不同程度的不對(duì)稱(chēng)性,從而來(lái)調(diào)節(jié)方框的表面等離激元共振模式,產(chǎn)生高階振動(dòng)模式或者補(bǔ)全一些在對(duì)稱(chēng)的結(jié)構(gòu)下無(wú)法被激發(fā)出來(lái)的共振級(jí)次。
[Abstract]:The surface isodissociation of precious metals is a kind of electromagnetic wave propagating along the surface of metals which is generated by the coupling of light and free electrons near the metal surface. Since its theory was put forward in the last century, more and more attention has been paid to it. The surface isotherms of metal nanoparticles will move with the change of external electromagnetic field. Resonance occurs when the frequency of the surface plasma is the same as that of the external electromagnetic field. The size and morphology of metal nanostructures have a great influence on the resonance characteristics of surface isoexcitators. Therefore, we can adjust these parameters to construct the surface equidistant components with different optical properties, which can break through the diffraction limit of light. In order to achieve higher precision than the traditional optical devices to operate light, so in many fields have shown great application prospects, such as surface enhanced spectra, isobaric optical waveguides, solar cells. As well as biosensors and so on. With the gradual deepening of various theoretical research and the technology of metal particle processing in the micro-nano scale is more and more mature. The properties of surface isobaric elements of different metal nanostructures have become a very hot research topic. This research has also formed a rapidly developing new subject. Based on the current research status of surface isophosphonic photonics, most of the current studies are focused on complex two-dimensional nanostructures. In this paper, a method of producing complex surface isopultionic properties by coupling simple geometric structures is proposed. This paper is mainly divided into three parts. In the first part, some numerical calculation methods and the software used in this paper are introduced. In the second part, some basic nanostructures and surface isopherons of nano-dimer are introduced. In the third part, the box-square disk is designed. SRD) composite structure has studied the optical properties of surface isoexcitators and focused on some high order surface resonance characteristics due to the breaking of symmetry. The contents of each part are described as follows; In the first part, some commonly used numerical calculation methods are introduced, and the numerical calculation software used in this paper is briefly introduced, in which the FDTD method is mainly introduced. Discrete dipole approximation (DDA) method. And finite element FEMM). Three common numerical simulation algorithms are presented in this paper. Then, the COMSOL using finite element method in this paper is introduced emphatically. Multiphysics software. For which modeling needs to pay attention to some of the settings such as boundary conditions. The setting of the port and the calculation of the S parameters, the initial value and the setting of the background field are all explained in detail. The second part: we study the properties of the surface isopotons of some relatively basic structures from the simplest nanospheres. After that, some properties of surface isophosphorus of nano-particle dimer are introduced. A method of generating dark isoexciton resonance mode in dimer is introduced. Part 3: a frame / disk SRD structure is designed. By changing the relative position of the square disk and the square frame of the SRD structure, different degrees of asymmetry can be obtained, thus adjusting the surface isoexciton resonance mode of the square frame. A higher order vibration mode is produced or some resonance order that cannot be excited under a symmetric structure is complemented.
【學(xué)位授予單位】：陜西師范大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類(lèi)號(hào)】：TB383.1

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相關(guān)期刊論文 前1條

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本文編號(hào)：1461030