由於表面等離子體激元可以將電磁場限制在金屬表面,從而產生強烈的場強增強效果,因此在納米光子學和生物光子學方面具有廣泛的應用價值,其中包括高性能發光二級管、光伏電池、超高分辨率光學成像和超靈敏分子檢測等。尤其在單分子和醫學診斷方面,基於表面等離子體共振的生物傳感器獲得了越來越多的青睞。本論文包括兩部份。第一部份著重討論二維週期性洞陣列的表面等離子體特性,而第二部份則是研究這種洞陣列結構在表面等離子體共振傳感方面的應用。 / 在第一部份中,表面等離子體模式被分為非簡並模式(m,O) 和簡並模式(m,±n)兩種情況分別加以討論。首先,結合實驗結果和理論模型,我們對非簡並模式的衰減壽命和激發效率進行了研究。通過光干涉光刻法和薄膜沉積技術,一系列不同幾何結構的洞陣列樣品被製備出來,且這些樣品具有很高的重複性。利用角分辨色散關係進行模式識別以及確定這些模式的衰減壽命和激發效率。通過調整起偏器和檢偏器的相對方向,表面等離子體模式的非輻射和輻射衰竭均可加以研究。結果發現,衰減壽命強烈依賴於單洞的幾何結構,而且這種行為可以用簡單的靜電模型并考慮高階修正加以解釋。從非輻射衰減和輻射衰減平衡的角度出發,激發效率對幾何結構和共振波長的依賴性也可以理解。對於簡并模式,由於存在稱合,對稱模式和反對稱模式分別被p 偏振激發和S偏振激發。它們的對稱性和對於衰減壽命和共振波長的修正可以用干涉法和模式耦合理論來理解。最後,利用多模耦合方程,我們對色散關係圖譜隨著洞深度增加而演化的情況也進行了探討。 / 第二部份對基於表面等離子體共振的生物傳感器與陣列幾何結構的關係進行了研究。結果發現,激發效率和衰減壽命對表面等離子體共振傳感器的分辨率都起到了關鍵性作用。在共振中,峰值高度和帶寬主要由表面等離子體的衰減速率控制。較低的衰減速率導致較清晰的峰值線型,從而產生較高的傳感器分辨率。因此,通過調整陣列的幾何結構以產生非常低得輻射衰減速率,表面等離于體共振傳感器的品質因數可高達104.8/RIU ,這已經超過了基於梭鏡和納米粒子對應器件的性能表現。 / Surface plasmon polaritons (SPPs) generate a strong localized electromagnetic field on metal surface and thus are promising for nano- and bio-photonics including high performing light-emitting diodes and photovoltaic cells, super-high resolution optical imaging, ultra-high sensitive bimolecular detection, etc. In particular, the application of SPPs on surface plasmon resonance (SPR) biosensor has drawn much more attention recently because of the attempt to realize single molecule detection in medical diagnosis. / This thesis contains two parts. The first part focuses on studying the basic plasmonic properties of two-dimensional periodic hole arrays while the second part concentrates on the application of hole arrays on SPR sensing. / In the first part, SPPs modes on hole arrays are classified into nondegenerate mode (m, 0) and degenerate mode (m, ±n). For nondegenerate mode, its decay lifetime and generation efficiency are studied both experimentally and theoretically. By combining interference lithography and thin film deposition, a set of arrays with a wide range of geometry has been fabricated with high reproducibility. The dispersion relations of arrays are studied by angle-dependent reflectivity for mode identification and detenninations of SPP decay lifetime and generation efficiency. In particular, through orienting the polarization of the specular reflection either parallel or orthogonal to that of the incidence, we can access both the nonradiative and radiative decays of SPPs at different resonance wavelengths. As a result, it is found that decay lifetime is strongly dependent on the geometry of single hole and its behaviors can be understood by using a simple quasi-static model taking into account of the higher order correction as well as numerical simulation deduced by finite-difference timedomain. The dependence of generation efficiency on hole geometry or resonance wavelength can be understood in tenns of trade-off between nonradiative and radiative decay rates. Once these two decay rates equals to each other, the optimum generation efficiency is realized and the field enhancement gets the maximum. And the optimum parameters can be achieved by adjusting the hole geometry or the resonance wavelength. For degenerate mode, due to the coupling between (m, +n) and (m, -n) modes, a symmetric and an anti-symmetric modes are excited under pand s-polarized excitation, respectively. Their symmetries and modifications to the decay lifetime and resonance wavelength can be understood by using the interference method and coupled mode theory. Finally, generalized coupled mode equations are employed to know about the evolution of dispersion relation as hole depth increases. / The dependence of SPR biosensor on the generation and decay of SPPs are studied in the second part. Both the generation efficiency and decay lifetime of SPPs are found to be critical in governing the resolution of SPR biosensor. In SPR, the peak height and linewidth are primarily controlled by the decay rate of SPPs. Lower decay rate leads to sharper peak profile, which results in higher SPR resolution. Therefore, by tailoring the geometry of hole arrays to achieve a very low radiative decay rate, a SPR biosensor with figure of merit (FOM) reaching l04.8/RIU can be realized, which surpasses those of prism and nanoparticle counterparts. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Zhang, Lei = 表面等離子體激元對於週期性金屬納米結構幾何形狀的依賴性及其在生物傳感中的應用 / 張磊. / "November 2011." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 116-125). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Zhang, Lei = Biao mian deng li zi ti ji yuan dui yu zhou qi xing jin shu na mi jie gou ji he xing zhuang de yi lai xing ji qi zai sheng wu chuan gan zhong de ying yong / Zhang Lei. / Chapter Chapter1 --- Introduction --- p.1 / Chapter Chapter2 --- Theoretical Background --- p.7 / Chapter 2.1 --- Maxwell's equations --- p.7 / Chapter 2.2 --- Classic electromagnetic theory for dielectric properties of matter --- p.9 / Chapter 2.3 --- Surface plasmon polaritons at the dielectric/metal interface --- p.11 / Chapter 2.4 --- Excitation of surface plasmon polaritons --- p.16 / Chapter 2.4.1 --- Prism coupling --- p.17 / Chapter 2.4.2 --- Grating coupling --- p.17 / Chapter 2.5 --- lones calculus --- p.19 / Chapter 2.6 --- Finite-difference time-domain method --- p.22 / Chapter Chapter 3 --- Sample Preparation --- p.25 / Chapter 3.1 --- Interference lithography --- p.25 / Chapter 3.1.1 --- Substrate preparation --- p.26 / Chapter 3.1.2 --- Exposure --- p.27 / Chapter 3.1.3 --- Pattern development --- p.30 / Chapter 3.2 --- Thin film deposition --- p.30 / Chapter Chapter 4 --- Experimental Setups and Calibration --- p.33 / Chapter 4.1 --- Experimental setup for measuring dispersion relation --- p.33 / Chapter 4.2 --- Experimental setup calibration --- p.35 / Chapter 4.2.1 --- Calibration of spectrometer --- p.36 / Chapter 4.2.2 --- Calibration of movement stages --- p.38 / Chapter 4.3 --- Data presentation for dispersion relation --- p.40 / Chapter 4.4 --- Summary --- p.41 / Chapter Chapter 5 --- Understanding of Fundamental Properties of SPPs --- p.43 / Chapter 5.1 --- Excitation of SPPs on 2D hole arrays --- p.44 / Chapter 5.2 --- Properties of non degenerate modes and theoretical explanation --- p.53 / Chapter 5.2.1 --- Dependence of lifetime on hole geometry and theoretical explanation --- p.55 / Chapter 5.2.2 --- Dependence of generation efficiency on hole geometry and theoretical explanation --- p.63 / Chapter 5.3 --- Properties of degenerate modes and theoretical explanation --- p.70 / Chapter 5.3.1 --- Dependence of properties of degeneration modes on hole geometry by FDTD --- p.72 / Chapter 5.3.1.1 --- (0, ±l)[subscript s,a] modes --- p.72 / Chapter 5.3.l.2 --- (-1, ±l)[subscript s,a] modes --- p.76 / Chapter 5.3.2 --- Understanding of excitation of degenerate modes by using interference method --- p.79 / Chapter 5.3.3 --- Understanding of coupling between degenerate modes by using coupled mode theory --- p.85 / Chapter 5.4 --- Evolution of dispersion relation as hole depth increases --- p.90 / Chapter 5.5 --- Summary --- p.95 / Chapter Chapter 6 --- Surface Plasmon Resonance Based Label Free Biosensor --- p.98 / Chapter 6.1 --- Basics of surface plasmon resonance (SPR) based biosensor --- p.98 / Chapter 6.2 --- State-of-the-art SPR biosensor --- p.101 / Chapter 6.3 --- SPR biosensor by using 2D metallic hole arrays --- p.102 / Chapter 6.4 --- Summary --- p.111 / Chapter Chapter 7 --- Conclusions --- p.112 / References --- p.116 / Publications --- p.126
Identifer | oai:union.ndltd.org:cuhk.edu.hk/oai:cuhk-dr:cuhk_328153 |
Date | January 2012 |
Contributors | Zhang, Lei, Chinese University of Hong Kong Graduate School. Division of Physics. |
Source Sets | The Chinese University of Hong Kong |
Language | English, Chinese |
Detected Language | English |
Type | Text, bibliography |
Format | electronic resource, electronic resource, remote, 1 online resource (xx, 127 leaves) : ill. (some col.) |
Rights | Use of this resource is governed by the terms and conditions of the Creative Commons “Attribution-NonCommercial-NoDerivatives 4.0 International” License (http://creativecommons.org/licenses/by-nc-nd/4.0/) |
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