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Studies of the decay of surface plasmon polaritons on periodic metallic nanostructures and related applications. / 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 / Studies of the decay of surface plasmon polaritons on periodic metallic nanostructures and related applications. / 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 yongJanuary 2014 (has links)
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.
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Probing defect and magnetic structures on the nanoscaleKallis, Alexis January 2010 (has links)
This thesis reports on experimental research on structural defects and magnetic species on the nanoscale. The latter project involved considerable development work on the production of a spin-polarised mono-energetic positron beam. The construction of the system is described through various trial steps with emphasis on the methods of maximum practical polarization of the positron beam and of electrons in the sample with the smallest possible loss of beam intensity. A new sodium-22 source capsule was purchased, having beryllium foil backing to minimise the depolarisation effects of backscattering, and the source-moderator spacing was increased. Different types of sample were tested, varying in atomic structure, purity, magnetic susceptibility, electronic structure, and electric conductivity - including iron of different purity and structure, mu metal and solid oxygen. After these tests measurements were taken on single crystal iron, and the results suggest that the positron response to magnetic structures is very small, and that prospects for depth profiling of dilute magnetic systems are not favourable at this time. A large number of other investigations have been performed on non-magnetic defect structures in various materials. Variable Energy Positron Annihilation Spectroscopy – here involving beam-based Doppler broadening – was applied to novel materials of relevance to photonic or electronic structures on the nanoscale. These included thin films of technological interest such as AlGaN and Ar plasma-treated TiO2: silicon and silicon-on-insulator samples implanted with He and Si ions to engineer vacancies: Si-rich SiO2 and SiN to form nanocrystals for photonic applications in which new findings on the evolution of the nanocrystals, and the role of the nanocrystal-oxide interface in optical emission, could be very useful in the technological development of such systems: and a study of the structural phase and nano-pore properties of water ice films grown from vapour on a cold copper surface. The variety of these experimental studies serves to underline the wide applicability of positron beam spectroscopy in research on defect and nanostructure structures. A list of papers published to date resulting from this work is given at the end of the thesis; a number of others are planned.
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Light interaction with graphene, related materials and plasmonic nanostructuresMilana, Silvia January 2015 (has links)
No description available.
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Metal oxide nanostructures for hybrid optoelectronic applicationsSaberi Moghaddam, Reza January 2015 (has links)
No description available.
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Formation of MgO nanorods by displacement reactions between Mg and ZnO. / 鎂和氧化鋅反應製備氧化鎂納米棒 / Formation of MgO nanorods by displacement reactions between Mg and ZnO. / Mei he yang hua xin fan ying zhi bei yang hua mei na mi bangJanuary 2004 (has links)
Yau Man Yan Eric = 鎂和氧化鋅反應製備氧化鎂納米棒 / 游文仁. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references. / Text in English; abstracts in English and Chinese. / Yau Man Yan Eric = Mei he yang hua xin fan ying zhi bei yang hua mei na mi bang / You Wenren. / Acknowledgement --- p.i / Abstract --- p.ii / 摘要 --- p.iii / Table of contents --- p.iv / List of tables --- p.viii / List of figures --- p.ix / Chapter Chapter 1 --- Introduction / Chapter 1.1 --- Nanostructured materials --- p.1-1 / Chapter 1.2 --- Application of nano-materials --- p.1-1 / Chapter 1.3 --- Current development of nano-materials --- p.1-2 / Chapter 1.4 --- Synthesis of nano-materials --- p.1-2 / Chapter 1.4.1 --- Physical methods --- p.1-3 / Chapter 1.4.1.1 --- Physical vapor deposition --- p.1-3 / Chapter 1.4.1.2 --- Arc-discharge process --- p.1-3 / Chapter 1.4.1.3 --- Laser ablation --- p.1-4 / Chapter 1.4.2 --- Chemical methods --- p.1-4 / Chapter 1.4.2.1 --- Chemical vapor deposition --- p.1-4 / Chapter 1.4.2.2 --- Metal-organic chemical vapor deposition (MOCVD) --- p.1-4 / Chapter 1.4.2.3 --- Solgel method --- p.1-5 / Chapter 1.5 --- Study on growth mechanism of nano-materials --- p.1-5 / Chapter 1.5.1 --- Vapor-liquid-solid (VLS) mechanism --- p.1-5 / Chapter 1.5.2 --- Vapor-solid (VS) mechanism --- p.1-6 / Chapter 1.6 --- Applications of Magnesium Oxide (MgO) materials --- p.1-7 / Chapter 1.7 --- Previous works on MgO nanostructures --- p.1-8 / Chapter 1.7.1 --- Network like MgO nanobelts --- p.1-8 / Chapter 1.7.2 --- Decorated MgO crystalline fibers --- p.1-9 / Chapter 1.7.3 --- Mg2Zn11 - MgO belt-like nanocables --- p.1-9 / Chapter 1.7.4 --- MgO nanowires with uniform diameter distribution --- p.1-10 / Chapter 1.7.5 --- Aligned MgO nanorods on MgO (100) substrates --- p.1-11 / Chapter 1.8 --- Objectives and approaches of this project --- p.1-12 / Chapter 1.8.1 --- Addition of sodium chloride (NaCl) --- p.1-13 / Chapter 1.9 --- Thesis Layout --- p.1-13 / Chapter 1.10 --- References --- p.1-15 / Chapter Chapter 2 --- Methodology and Instrumentation / Chapter 2.1 --- Introduction --- p.2-1 / Chapter 2.2 --- Powder Metallurgy --- p.2-1 / Chapter 2.3 --- Sample fabrication --- p.2-1 / Chapter 2.3.1 --- Starting materials --- p.2-1 / Chapter 2.3.2 --- Cold pressing --- p.2-2 / Chapter 2.3.2.1 --- Single pellet method --- p.2-2 / Chapter 2.3.2.2 --- Double pellet method --- p.2-3 / Chapter 2.3.3 --- Argon tube furnace sintering --- p.2-3 / Chapter 2.4 --- Study of fabrication parameters --- p.2-4 / Chapter 2.4.1 --- Heat treatment temperature --- p.2-4 / Chapter 2.4.2 --- NaCl content in sample --- p.2-4 / Chapter 2.4.3 --- Duration of heat treatment --- p.2-5 / Chapter 2.5 --- Control Experiments --- p.2-5 / Chapter 2.5.1 --- Effect of addition of NaCl --- p.2-5 / Chapter 2.5.2 --- Effect of residual oxygen --- p.2-5 / Chapter 2.5.3 --- Geometrical effect of experimental setup --- p.2-6 / Chapter 2.5.3.1 --- Compressed double pellet method --- p.2-6 / Chapter 2.5.3.2 --- Powder on Magnesium pellet method --- p.2-6 / Chapter 2.5.3.3 --- Single pellet method --- p.2-7 / Chapter 2.6 --- Characterization Methods --- p.2-7 / Chapter 2.6.1 --- Thermal analysis - Differential thermal analyzer (DTA) --- p.2-7 / Chapter 2.6.2 --- Structural analysis --- p.2-7 / Chapter 2.6.2.1 --- Scanning electron microscopy (SEM) --- p.2-7 / Chapter 2.6.2.2 --- Transmission electron microscopy (TEM) --- p.2-8 / Chapter 2.6.3 --- Phases determination - X-ray powder diffractometry (XRD) --- p.2-8 / Chapter 2.7 --- References --- p.2-9 / Chapter Chapter 3 --- Results of Mg-ZnO-NaCl System / Chapter 3.1 --- Introduction --- p.3-1 / Chapter 3.2 --- Results of thermal analysis --- p.3-1 / Chapter 3.2.1 --- Chemical reactions --- p.3-1 / Chapter 3.2.2 --- DTA results --- p.3-2 / Chapter 3.3 --- Variation of heat treatment temperature --- p.3-3 / Chapter 3.3.1 --- XRD pattern --- p.3-3 / Chapter 3.3.2 --- SEM images --- p.3-4 / Chapter 3.4 --- Variation of NaCl content --- p.3-5 / Chapter 3.4.1 --- TEM analysis --- p.3-5 / Chapter 3.5 --- Variation of duration of heat treatment --- p.3-6 / Chapter 3.6 --- Additional findings --- p.3-7 / Chapter 3.7 --- Discussions --- p.3-7 / Chapter 3.8 --- References --- p.3-10 / Chapter Chapter 4 --- Results of Control Experiments / Chapter 4.1 --- Introduction --- p.4-1 / Chapter 4.2 --- The study of Mg-ZnO system --- p.4-1 / Chapter 4.3 --- The study of residual oxygen effect --- p.4-2 / Chapter 4.4 --- The study of geometrical effect of experiment setup --- p.4-2 / Chapter 4.5 --- Discussions --- p.4-3 / Chapter 4.5.1 --- Effect of addition of NaCl --- p.4-3 / Chapter 4.5.2 --- Effect of residual oxygen --- p.4-3 / Chapter 4.5.3 --- Role of ZnO --- p.4-4 / Chapter 4.5.4 --- Growth model --- p.4-4 / Chapter 4.6 --- References --- p.4-7 / Chapter Chapter 5 --- Conclusions and Further Studies / Chapter 5.1 --- Conclusion --- p.5-1 / Chapter 5.2 --- Further studies --- p.5-2 / Chapter 5.3 --- References --- p.5-3
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Photoluminescence studies of quasi-one-dimensional ZnSe nanostructures in different ambient gases. / 在不同氣體中一的維硒化鋅鈉米結構的發光研究 / Photoluminescence studies of quasi-one-dimensional ZnSe nanostructures in different ambient gases. / Zai bu tong qi ti zhong yi de wei xi hua xin na mi jie gou de fa guang yan jiuJanuary 2005 (has links)
Ng Ching Man = 在不同氣體中一的維硒化鋅鈉米結構的發光研究 / 吳靜雯. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 67-69). / Text in English; abstracts in English and Chinese. / Ng Ching Man = Zai bu tong qi ti zhong yi de wei xi hua xin na mi jie gou de fa guang yan jiu / Wu Jingwen. / Contents / Acknowledgements --- p.ii / Abstract --- p.iii / Chapter Chapter 1- --- Introduction --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.2 --- Motivation --- p.3 / Chapter 1.3 --- Our Work --- p.4 / Chapter Chapter 2 - --- Experiment --- p.5 / Chapter 2.1 --- MOCVD System --- p.5 / Chapter 2.2 --- Metalorganic Sources --- p.5 / Chapter 2.3 --- Substrates --- p.7 / Chapter 2.4 --- Growth of ZnSe Nanowires --- p.7 / Chapter 2.5 --- Sample Passivation --- p.8 / Chapter 2.6 --- PL measurements --- p.8 / Chapter 2.7 --- Ambient Gases --- p.9 / Chapter 2.8 --- Gases Handling Apparatus --- p.9 / Chapter 2.9 --- Ambient Gases and Laser Power Control in PL Measurements --- p.11 / Chapter Chapter 3 - --- Characterization --- p.13 / Chapter 3.1 --- Photoluminescence --- p.13 / Chapter 3.2 --- Secondary Electron Microscopy --- p.14 / Chapter 3.3 --- X-Ray diffraction --- p.15 / Chapter Chapter 4 - --- Results --- p.16 / Chapter 4.1 --- ZnSe Nanowires Grown on Si(100) --- p.16 / Chapter 4.1.1 --- Morphology and Structure of the As Synthesized Sample --- p.16 / Chapter 4.1.2 --- Morphology and Structure of the Sample after Passivation --- p.17 / Chapter 4.2 --- Effect of Ambient Condition on Photoluminescence --- p.19 / Chapter 4.2.1 --- PL in Vacuum Ambient --- p.20 / Chapter 4.2.2 --- PL Spectra in different Ambient Gases --- p.21 / Chapter 4.2.3 --- PL Reversibility --- p.23 / Chapter 4.3 --- "Effect of Pressure, Concentration and Power of Excitation on the Photoluminescence of Nanowires" --- p.26 / Chapter 4.3.1 --- Ambient Pressure --- p.27 / Chapter 4.3.1.1 --- H2S --- p.27 / Chapter 4.3.1.2 --- H2 --- p.30 / Chapter 4.3.1.3 --- CO --- p.32 / Chapter 4.3.2 --- Ambient Concentration --- p.33 / Chapter 4.3.2.1 --- H2S --- p.33 / Chapter 4.3.2.2 --- H2 --- p.36 / Chapter 4.3.3 --- Excitation Power --- p.38 / Chapter 4.3.3.1 --- H2S --- p.38 / Chapter 4.3.3.2 --- H2 --- p.40 / Chapter 4.3.3.3 --- CO --- p.41 / Chapter Chapter 5 - --- Discussions --- p.42 / Chapter 5.1 --- Quality of nanowires --- p.42 / Chapter 5.2 --- Surface Reaction --- p.43 / Chapter 5.2.1 --- Surface States --- p.43 / Chapter 5.2.2 --- Gas-surface interaction --- p.46 / Chapter 5.2.2.1 --- Physiosorption --- p.46 / Chapter 5.2.2.2 --- Chemisorption --- p.47 / Chapter 5.3 --- (NH4)2S passivation --- p.48 / Chapter 5.3.1 --- Etching --- p.48 / Chapter 5.3.2 --- (NH4)2S passivation --- p.48 / Chapter 5.4 --- PL increase in Vacuum --- p.50 / Chapter 5.5 --- Effects of different Gases --- p.50 / Chapter 5.5.1 --- H2S --- p.50 / Chapter 5.5.2 --- H2 --- p.53 / Chapter 5.5.3 --- CO --- p.54 / Chapter 5.5.4 --- Other explanations --- p.54 / Chapter 5.6 --- The amount of Intensity Change --- p.56 / Chapter 5.7 --- Rates of Adsorption and Desorption --- p.56 / Chapter Chapter 6 - --- Conclusions --- p.58 / Appendices --- p.60 / Chapter I - --- Fitted parameter of the adsorption and desorption of H2S and CO --- p.60 / Chapter II - --- Calculation of gas and photon fluxes --- p.65 / References --- p.67
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Preparation of rare-earth (Eu3+, Tb3+, and Yb3+) doped Y2O3 luminescent ceramics by the use of reverse micellesCorral, Jessica Olga. January 2004 (has links)
Thesis (M.S.)--University of Nevada, Reno, 2004. / "December 2004." Includes bibliographical references (leaves 59-63). Online version available on the World Wide Web.
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Mesoscopic spin Hall effect in semiconductor nanostructuresZarbo, Liviu. January 2007 (has links)
Thesis (Ph.D.)--University of Delaware, 2007. / Principal faculty advisor: Branislav Nikolic, Dept. of Physics & Astronomy. Includes bibliographical references.
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Study of Nanostructure Copper Oxide with Controlled Morphologies by a Simple Solution RouteCheng, Hsiu-yi 09 January 2009 (has links)
Copper oxide with various morphologies, such as nanocubes, nanorods, and nanoribbons was synthesized from the H2O/C2H5OH solution of Cu(OAc)2/NEt3 with or without tetraoctylammonium bromide (TOAB) under mild conditions.
In the system of Cu(OAc)2/NEt3 (0.05 mmole : 7.9 mmole) with 0.75 mmole of TOAB in H2O/C2H5OH (10 mL : 40 mL) solution, We found that nanocubes of CuO spontaneously self-assembled into nanorods and then nanosheets with the increasing of reaction time.
Structural characterization of the CuO nanorods shows that the rod grows primarily along the [010] direction. Nanorods of CuO were also characterized by TEM, HR-TEM, SAED, and XRD.
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Croissance localisée de boîtes quantiques d'inas sur une surface nanostructurée d'INP (001) pour une application en composants photoniquesTurala, Artur Gendry, Michel January 2007 (has links) (PDF)
Thèse doctorat : Matériaux : Ecully, Ecole centrale de Lyon : 2007. / 139 références.
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