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Dissertation submitted in partial compliance with the requirements for the Master's Degree in Technology: Homoeopathy, Technikon Natal, 1997. / The purpose of this investigation was to analyse and compare the Nuclear Magnetic Resonance (NMR) spectra of samples of quinquagenimillesimal (LM) potencies of homoeopathic Sulphur and a lactose-based control produced according to Hahnemann, in order to evaluate homoeopathic medicines thus prepared. It was hypothesised that differences existed in the spectra of respective Sulphur samples, control samples, and between parallel samples of Sulphur and control. It was further hypothesised that these differences correlated proportionately with the degree of potency of samples. The design of the investigation was that of a scientific experiment. Potencies of Sulphur and a lactose-based control were prepared (according to the directions of Hahnemann*) to the LM10 level. LM2, LM6 and LM10 liquid potencies (95% ethanol) of each group were then prepared in =20.8160 ml volumes and despatched for sampling and measurement. NMR spectroscopy was conducted on fifteen (15) samples of each potency. These were prepared in coaxial sample tubes using deuterium oxide (020) as an extemal lock and dioxane as a reference. Samples were drawn and measured in overlapping sequence by the Department of Chemistry, University of Cape Town. The spectrometer em. ployed was a. Varian VXR200 operating at a frequency of 200.057 MHz. Acquisition time for each sample was 3.727 seconds, using a pulse width of 6\xB0. Measurement of each sample was repeated eight times, at a constant temperature of 298.1 K (250. OC) / M

A research report submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor off Philosophy Johannesburg, 2015 / Background Objective volumetric assessment of white matter in children with HIV involves post M processing, while corpus callosum (CC) thickness measurement on midMsagittal MRI may represent a rapid surrogate marker. Aim To determine whether the thickness of the CC on midMsagittal MRI can be used as a surrogate marker of brain volume in children with HIV Mrelated brain disease and in appropriate controls and to determine whether thickness at particular locations correlates with mental developmental scores and laboratory markers of immunity. Methods A retrospective analysis of 33 children with HIV Mrelated neurology(range 7 M 49 months; median31 months; mean 30 months; 16 boys and 17 girls) and matched controls (range 13 – 48 months; median 34 months; mean 32 months; 6 boys and 5 girls) was performed. A custom software tool imported sagittal MRI images, divided the midline CC contour into 40 segments and measured the thickness of each segment as well as the length of the CC. Brain volume (total brain volume (TBV); white matter volume (WMV);grey matter volume (GMV)) was determined using MATLAB and Statistical Parametric Mapping software. Overall and segmental CC mean and maximum thickness and CC length were checked for correlation with brain volume, Griffiths mental development scores(GMDS) and laboratory parameters. Results Griffiths scores in patients were ‘low average’ (mean Griffiths general quotient (GQ) of 84, range 72 – 101; ‘locomotor’ 84, range 59 – 116; ‘language’ 80; range57 –118). There was no statistical difference in overall and regional CC thickness, CC length, TBV, GMV and WMV between patients and controls. Significant correlation was found in patients for the premotor CC mean with age (p = 0.04). Other significant correlations of CC measurements and laboratory / clinical parameters were the prefrontal CC max with in adir CD4 (p=0.046)(+vecorrelation); motor CC max with GQ (p=0.028) (Mve!correlation) and CC length with CD4(p=0.04) (Mve correlation). Significant correlations between CC thickness and brain volume were found in patients and controls for the CC mean and TBV (p=0.049)(+ve correlation);premotor CC mean and TBV (p=0.039)(+ve correlation); sensory CC mean and TBV (p=0.022)(+ve correlation); prefrontal CC max and WMV (p=0.019)(+ve correlation); premotor CC mean and WMV (p=0.019)(+ve correlation and for the premotor CC max and WMV (p=0.023)(+ve correlation). Conclusion: This research met its objectives in demonstrating a statistically significant, albeit weak, correlation between CC thickness and brain volume in patients and controls, even though patients were not shown to have significantly diminished brain volumes as compared to controls.

近年來，表面等離子體因為可以在金屬表面激發極強的局部電磁場而受到廣泛的關注。它是光和物質之間的重要的聯繫。基於它在納米量級上操控和引導光子的能力，表面等離子體已廣泛應用于納米和生物光學之中，比如生物傳感器，表面增強拉曼散射，光鑷，發光二極管，太陽能電池和超材料等等。然而，儘管系統結構，材料特性，激發光波長和條件都會影響表面等離子體本身的特性以及它與材料之間的相互作用，這些外部條件的整體效果卻常常不為人所知。更重要的是，在表面等離子體和這些外部條件之間，似乎仍有未知的聯繫存在。比如，現在人們仍然不是很清楚激發表面等離子體的納米結構到底是怎樣控制它以及與它相關的特性的。 / 在這篇論文里，我們希望通過耦合模理論將這些外部條件和表面等離子體特性聯繫起來。耦合模理論提供了表面等離子體吸收和輻射壽命等內部參數以及它們與光相位，振幅，傳播方向的關係。因為這些外部條件和壽命參數，激發條件之間的聯繫廣為人知，我們因此就可以把這些外部條件和表面等離子體特性聯繫起來了。一旦獲得了這些壽命參數，我們亦可從另外一個角度研究表面等離子體的基本特性。比如，我們發現兩個簡併表面等離子體耦合除了形成超模式和次模式以外，它們的輻射壽命和吸收壽命都發生了改變。另外，我們在實空間和動量空間研究了表面等離子體衰變長度，群速度等其他內部參數，并發現它們和等離子體衰減及態密度有重要聯繫。我們還發現基於相位躍變的表面等離子體傳感器在臨界耦合時將獲得最優表現。最後，通過研究發光材料和表面等離子體之間的耦合效率，我們發現態密度在其中起了關鍵作用。 / Surface plasmons (SPs), which generate strong localized electromagnetic fields at metal surface, have been capturing worldwide attention recently because they establish an important link between light and matter. Due to their ability to route and manipulate photon at the nanoscale, SPs have been widely used in nano- and bio-photonics including biosensor, surface enhanced Raman scattering, optical tweezers, light emitting diodes, solar cell, and metamaterials, etc. However, although it is known that system geometry, material, wavelength, excitation condition are important in governing the behaviors of SPs as well as matter/SPPs interactions, how they work together in producing the final outcome is largely unknown. More importantly, there seems to be a "missing link" between these extrinsic parameters and the properties of SPs such that, for example, it is still not quite understood the exact roles of geometry play in controlling the SPs and their related properties. / In this thesis, we aim at bridging the link between extrinsic parameters and SPs properties based on temporal coupled-mode theory (CMT). CMT provides the knowledge of intrinsic parameters such as SPs radiative and absorption rates and their relationships with the phase, amplitude, and directionality of SPs. Because decay rates are strong function of system parameters, excitation condition, etc, connection between the extrinsic parameters and the SPs properties can now be established. With the decay rates and other accessories in hand, we study the fundamental of SPs from another perspective. For example, we examine how two degenerate SPs modes couple to yield a pair of dark and bright modes and find not only the radiation damping of SPs but also the absorption are modified. In addition, we study the decay length and the group velocity of SPs in real- and momentum- space to elucidate the interplay between the SPs losses and the wavevector-resolved projected density-of-optical-states (PDOS). We also explore the rate matching (i.e. critical coupling) for optimizing the phase-jump in SPs resonance sensing and achieve high figure of merit in sensing performance. Finally, the coupling between SPs and light emitters has been studied and it is found that their coupling rate is governed by PDOS. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Cao, Zhaolong = 表面等離子體激元在金屬納米洞陣列上的衰變研究及其應用 / 曹兆龍. / Thesis (Ph.D.) Chinese University of Hong Kong, 2014. / Includes bibliographical references (leaves 142-149). / Abstracts also in Chinese. / Cao, Zhaolong = Biao mian deng li zi ti ji yuan zai jin shu na mi dong zhen lie shang de shuai bian yan jiu ji qi ying yong / Cao Zhaolong.

by Ng Sik Tim. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaf 229). / by Ng Sik Tim. / Chapter 1 --- Introduction --- p.6 / Chapter 1.1 --- Resonances in open systems --- p.6 / Chapter 1.2 --- Descriptions of open optical systems --- p.11 / Chapter 1.3 --- The wave equations and E.M. fields --- p.17 / Chapter 2 --- The stabilization method --- p.20 / Chapter 2.1 --- Introduction --- p.20 / Chapter 2.2 --- Formalism --- p.23 / Chapter 2.2.1 --- The derivation of scattering phase shift --- p.23 / Chapter 2.2.2 --- The cumulative density of states --- p.25 / Chapter 2.3 --- Worked examples --- p.32 / Chapter 2.3.1 --- The importance of large b --- p.32 / Chapter 2.3.2 --- The comparison of different approaches --- p.35 / Chapter 2.3.3 --- Summary --- p.52 / Chapter 2.4 --- Other examples --- p.52 / Chapter 2.4.1 --- Discussions --- p.52 / Chapter 3 --- Completeness and orthogonality of QNM's --- p.64 / Chapter 3.1 --- Introduction --- p.64 / Chapter 3.2 --- QNM's of the scalar analog of electromagnetism --- p.65 / Chapter 3.3 --- The representation of Green's function --- p.66 / Chapter 3.4 --- The completeness of QNM's --- p.72 / Chapter 3.5 --- The orthogonality of QNM's --- p.73 / Chapter 3.6 --- Discussions --- p.75 / Chapter 4 --- Variational method for resonant states --- p.78 / Chapter 4.1 --- Introduction --- p.78 / Chapter 4.2 --- Formalism --- p.79 / Chapter 4.2.1 --- Complex variational method --- p.79 / Chapter 4.2.2 --- Non-linear variation --- p.82 / Chapter 4.2.3 --- Linear variation --- p.84 / Chapter 4.2.4 --- The orthogonality of approximate wave function --- p.85 / Chapter 4.3 --- Numerical examples --- p.86 / Chapter 4.3.1 --- A sketch of calculations --- p.86 / Chapter 5 --- The diagonalization method --- p.98 / Chapter 5.1 --- Introduction --- p.98 / Chapter 5.2 --- Completeness and orthogonality --- p.100 / Chapter 5.3 --- Formalism --- p.101 / Chapter 5.4 --- Numerical examples --- p.107 / Chapter 5.4.1 --- Descriptions of examples and results --- p.108 / Chapter 5.4.2 --- Summary of results --- p.131 / Chapter 5.5 --- Discussions --- p.134 / Chapter 5.5.1 --- The case with a > c --- p.134 / Chapter 5.5.2 --- A comparison with Fourier's series --- p.138 / Chapter 6 --- The Green's function method --- p.147 / Chapter 6.1 --- Formalism --- p.147 / Chapter 6.2 --- Numerical results --- p.154 / Chapter 6.3 --- Discussions --- p.173 / Chapter 7 --- The uniqueness theorem of QNM's --- p.179 / Chapter 7.1 --- A brief review --- p.179 / Chapter 7.2 --- Physical meanings of the conditions --- p.184 / Chapter 7.3 --- The uniqueness theorem of QNM's --- p.188 / Chapter 7.4 --- The generalization of diagonalization --- p.190 / Chapter 7.5 --- Derivation of Green's function method --- p.192 / Chapter 7.6 --- Numerical examples --- p.193 / Chapter 8 --- Conclusion --- p.204 / Chapter A --- The scalar wave equations --- p.207 / Chapter B --- The electromagnetic fields --- p.214 / Chapter C --- Second order expansion in B --- p.217 / Chapter D --- The derivation of D(w) --- p.220 / Chapter E --- The stability of eigenvectors --- p.223

表面電漿是由貴金屬表面電荷密度漲落引起的沿著金屬表面傳播的電磁波。在過去十年裡，表面電漿效應因其在光子器件，傳感，表面增強螢光，尤其是表面增強拉曼散射(SERS) 方面的應用而引起了廣泛的關注.許多著作中的結論已經證實了的預期的SERS 強度，因此使得基於各種不同納米結構中的熱點的SERS變成一種下一代超敏感生物傳感平臺。因為表面電漿的波長和材料介電性質密切相闕，受f於此，難以進一步減小，所以對於進一步的各種應用來說，保證產生高強度的表面電漿使至關重要。同時，用電漿實現納米光子器件已經引起了研完者長久的興趣。例如，基於等問距規則排列的密置金屬納米顆粒之間突破衍射極限的的近場耕合已經被用於傳輸光信號。但是，輻射和吸收損耗在此類波導中是很嚴重的。因此，設計新概念的電漿器件是急需的。 / 有鑒於上述種種問題，本論文集中于總結構和材料兩方面剪裁表面電漿以期達到下面的要點和目的: / (1)基於傳播電漿(PSPs) ，或者傳播電漿同局域電漿(LPRs) 的結合而發展新的簡單的器件，由此提供顯著的聚焦、電磁場和場強增強。這種器件可以應用於很多方面，包括依賴強場的生物分子傳感探測，以及非線性光學效應。 / (2) 設計基於增益介臂的低損耗的納米光子學器件，這種器件能夠為納米光子器件提供切實的可行性。針對表面電漿共振和電漿結構植于的介電環境之間聯繫，獲得其理論闡釋。這一工作將可以為傳感和器件設計提供深入的理解。 / 本論文中我們已經得到了如下的成果: / (1)一種基於將表面電漿聚焦到金屬盤中心孔而實現級聯放大增強的SERS 激勵源被提出和理論研究。這種器件提供了準均勻，水平偏振，較大面積的強SERS 激勵源。如時域有限差分(FDTD) 方法所揭試，強度譜線和波長範圍在650-1000 nm的近場性質展混出了一系列增強模式。在最佳的增強模式下，孔洞中的電場可以使得SERS 信號獲得四次方的進一步增強。同時一種解析模型也被提出來給FDTD結果以精確的解釋。我們的模型同時揭示了通過侵化金屬盤尺度而得到八次方場增強的可能性。我們的結果表明極強的電場增強，並且聚焦的電場是平行于金屬盤平面的效果，只能在中間包含一個孔洞的中空金屬盤(HMDs) 中才可能實現。這是因為金屬盤中間絶悸的問時的存在使得孔洞邊棒的電子不能流通間隙，進進而使得高強度的電場可以存在。另一方面，在實心的金屬盤的情形下，電子流會傾向於抑制到達中心的表面電漿的強度。除了產生高度優化的SERS 熱點，這種大面積的活性孔洞在螢光增強和非線性光學中也提供了一些潛在的應用。 / 除了中空金屬盤，基於經由增孟輔助下PSPs 的LPRs 之間的衍射共掠，我們開發了另一種一種高度侵化的熱點。由此得到的器件被理論上分析。衍射共振的過程是經由下述過程實現的:由LPRs 實現的光場局域化， LPRs 和PSPs 相互作用，以及通過PSPs 的能量傳遞。我們的研究表明通過給PSPs 引入光學增孟，可以從一種激光過程中的到LPRs 非常強的電磁場增強。我們發現通過現實的增豆豆水平，局域電場的增強引子可以達到10⁷。因此，我們為實現依賴強電場的單分子SERS提供了一種理想的方案，並且這種方案也是一種納米激光的新機制。 / (2) 基於增孟輔助的電漿共振金屬納米顆粒鏈，我們提出了一種低損耗納米尺度的波導。我們證明通過引入增孟材料或者引入適當的介電材料作為周圍環境，波導的損耗可以顯著減小。為了得到低損耗傳翰的復介電譜，我們開發了一種高效的膺正交基展開(POBE) 方法。本徵模式分析揭示了低損耗模式的物理源頭，同時給出了除了基於單體偶極共振傳輸之外能量傳輸的可能性。我們提出一種基於電子書刻蝕和化學合成納米顆粒的一種製備方案。這種電漿波導可以構成納米光學器件的基石，尤其是用於集成納米光子學線路。同時，我們原創的揭示表面電漿的物理機理的POBE 方法可以用於進一步研究優化增豆豆輔助的電漿結構，進而設計良好的納米光子器件。 / 本論文始於一個古老問題:宏觀尺度下基於傳統介電材料光聚焦和傳導，并最後終結於納米尺度內經由增益材料和電漿結構的表面電漿的聚焦、和引導。論文結尾，本文給出了展望以及幾種可能的器件實現方案。 / Surface plasmons (SPs) are electromagnetic waves that propagate along the surface of a noble metal via fluctuations in electron density. In the last decade, SPs effects gained widespread attention for their potential application in photonic devices, sensing, surface-enhanced fluorescence, especially Surface-Enhanced Raman Scattering (SERS). Many published results have confirmed the expected strengths of SERS, hence making it possible for SERS to become a next generation ultra-sensitive biosensing platform, which may take the form of various nano-structures in order to achieve optimized hot spots. While the wavelength of SPs is closely related to material dielectric properties and has limited scope for further reduction, it is of critical importance to ensure that SPs are being generated with the highest intensity before any further application advancement is possible. Meanwhile, plasmonics has aroused longstanding interests among researchers to realize nanophotonic devices. For example, ordered arrays of closely spaced metallic nanoparticles (MNP) have been employed to transport optical signals via near-field coupling below the diffraction limit. However, radiation and absorption losses in these waveguides can be serious. New concepts for novel plasmonic devices are essential. / In light of these issues, this thesis focuses on tailoring SPs from the viewpoints of structural and material properties with the following objectives: / (1) To develop a new class of simple plasmonic devices based on tailoring of propagating surface plasmons (PSPs) or cooperation between PSPs and localized plasmon resonance (LPRs) to offer significant field focusing and intensity enhancement. It can serve a wide range of applications, including high field related biomolecular sensing and detection as well as non-linear optical effects. / (2) To design low loss nanophotonic wave guides based on gain medium, which may offer real opportunity for practical nanophotonic devices. To obtain a theoretical interpretation of relationship between surface plasmon resonance and host environment where the plasmonic structure embedded. This study should provide further insight towards sensing and device design. / We have achieved the following results in this project: / (1) A novel SERS excitation source based on focusing of surface plasmons around the center hole of a metal disk for cascaded enhancement is put forward and studied theoretically. The device offers intense SERS excitation with quasi-uniformity and horizontal polarization over a comparatively large hole. As revealed by fmite-difference time-domain (FDTD) method, the intensity spectra and the characteristics of the near field for the wavelength range of 650-1 000 nm exhibit a number of enhancement modes. Electric field intensity of the optimal mode enhances the SERS signal inside the hole by over four orders. An analytical model was also developed to gain precise interpretation on FDTD results. Our model also reveals the possibility of achieving eight orders of enhancement by optimizing the scale of the disk. Our results indicate that much higher electric field enhancement in hollow metal disks (HMDs) can only be possible when we have a hole at the centre and the direction of the focusing field is parallel to the surface of the plasmonic device. This is because of the presence of an insulating gap at the center, that higher level of electric field can exist as electrons are not allowed to flow pass the gap. On the other hand, in the case of a solid metal disk, the flow of mobile electron will tend to dampen the amplitude of the arriving SPs. In addition to generation of highly optimized hot spots for SERS, the large active hole also offers potential applications in fluorescence enhancement and nonlinear spectroscopy. / In addition to HMDs, we also develop a kind of highly optimized hot spots based on diffraction coupling between LPRs via gain-assisted PSPs. Thus derived device was theoretically analyzed. The process of diffraction coupling is achieved via localization of light by LPRs, LPRs-PSPs interplay and PSPs transfer. Our study shows that by incorporating optical gain to PSPs, a very strong boost of the electromagnetic enhancement of LPRs can be expected from a lasing process. We find that with a practical gain level, the enhancement factor of local electric field intensity can be larger than 10⁷. Hence, we offer an ideal configuration to realize high-field dependent single molecule SERS and also a newly applied physical scheme for nano-Iaser. / (2) We propose a low-loss nanoscale wave guide based on gain-assisted plasmonic resonance MNP chain. We demonstrate that by employing a gain material or even an appropriate dielectric for the host environment, waveguide loss can be reduced dramatically. A highly efficient pseudo-orthonormal basis expansion (POBE) method for obtaining the complex dielectric spectra of the low-loss transmission has been developed. Eigenmode analysis revealed the physical origin of those low-loss wave guiding modes, which opens the possibility to achieve waveguiding other than using conventional dipolar resonances of individual particles. A scheme based on electron beam lithography and chemically synthesized nanoparticles has been proposed to fabricate the device. Such plasmonic waveguides may serve as building blocks for making nanoscale optical devices especially for integrated nanophotonic circuits. Meanwhile, the originally developed POBE method, which reveals the general physical mechanism of SPs, can be used to further explore optimized gain-assisted plasmonic structures to design favorable nanophotonic devices. / This thesis begins with an old problem: light focusing and guiding in macroscopic scale with traditional dielectric, and sum up finally with SPs focusing and guiding in nanoscale with gain material and plasmonic material. An outlook is presented at last with several potential schemes for the device realization. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Zhang, Haixi. / "September 2011." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 124-139). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Chapter Chapter1 --- Introduction --- p.1 / Chapter 1.1 --- Towards field intensity focusing and guiding of electromagnetic wave --- p.1 / Chapter 1.2 --- Surface plasmons as a route to realize electromagnetic field focusing and waveguiding in nanoscale --- p.3 / Chapter 1.3 --- Structure of this thesis --- p.10 / Chapter Chapter2 --- Plasmonic near field engineering: structural and material aspects --- p.13 / Chapter 2.1 --- Light focusing using near field oflocalized plasmon resonances --- p.13 / Chapter 2.2 --- Plasmonic near field focusing through propagating surface plasmons --- p.30 / Chapter 2.3 --- Various schemes for near field focusing through surface plasmons --- p.33 / Chapter 2.4 --- Guiding surface plasmons in nanoscale --- p.35 / Chapter 2.5 --- Gain-assisted surface plasmons: a different path to field enhancement and guiding --- p.38 / Chapter Chapter3 --- Surface plasmons: characteristics and methodology --- p.42 / Chapter 3.1 --- Characteristics of localized plasmon resonance --- p.42 / Chapter 3.2 --- Localized plasmon resonance: Mie theory and its variations --- p.44 / Chapter 3.3 --- Characteristics of propagating surface plasmons --- p.49 / Chapter 3.4 --- Reflection Pole Method for studying propagating surface plasmons in multilayer structures --- p.55 / Chapter 3.5 --- Pseudo-orthonormal basis expansion method: a new mathematical scheme for modeling surface plasmons --- p.58 / Chapter Chapter4 --- High field generation through intensity focusing of propagating surface plasmons --- p.62 / Chapter 4.1 --- Introduction --- p.62 / Chapter 4.2 --- The hollow metal disk design and its characteristics --- p.64 / Chapter 4.3 --- Quasi-uniform excitation source based on focusing of propagating surface plasmons for cascade enhancement of surface enhanced Raman scattering --- p.68 / Chapter 4.4 --- Conclusions and outlook --- p.78 / Chapter Chapter5 --- High field generation through intensity enhancement of localized plasmon resonance from gain-assisted diffraction coupling --- p.81 / Chapter 5.1 --- Introduction --- p.81 / Chapter 5.2 --- Diffraction excitation of localized plasmon resonance from propagating surface plasmons --- p.83 / Chapter 5.3 --- Diffraction coupling of localized plasmon resonance through gain-assisted propagating surface plasmons --- p.89 / Chapter Chapter6 --- Gain-assisted plasmonic waveguides based on nanoparticle chains: an effective device approach for achieving low loss in nanoscale dimensions --- p.97 / Chapter 6.1 --- Introduction --- p.97 / Chapter 6.2 --- Theoretical study of near-field particle interactions in active plasmon wave guides --- p.99 / Chapter 6.3 --- Routing and splitting of electromagnetic energy in nanosphere plasmon waveguides --- p.103 / Chapter 6.4 --- Conclusions --- p.107 / Chapter Chapter7 --- Conclusions and outlook --- p.109 / Appendix --- p.117 / Bibliography --- p.124