Fong King Yan = 光栅衍射及含週期結構的金屬片的透射增強效應的理論研究 / 方敬恩. / Thesis submitted in: September 2006. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 111-119). / Abstracts in English and Chinese. / Fong King Yan = Guang zha yan she ji han zhou qi jie gou de jin shu pian de tou she zeng qiang xiao ying de li lun yan jiu / Fang Jing'en. / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Review on Grating Theories --- p.6 / Chapter 2.1 --- Basic Concepts --- p.6 / Chapter 2.1.1 --- Maxwell's Equations --- p.6 / Chapter 2.1.2 --- Translational Symmetry --- p.8 / Chapter 2.1.3 --- TM and TE Polarizations --- p.10 / Chapter 2.1.4 --- The Grating Equation --- p.11 / Chapter 2.2 --- Rayleigh's Method --- p.12 / Chapter 2.3 --- Integral Method --- p.13 / Chapter 2.4 --- Classical Modal Method --- p.15 / Chapter 2.5 --- Rigorous Coupled-Wave Analysis --- p.16 / Chapter 2.5.1 --- General Form of Electromagnetic Modes --- p.17 / Chapter 2.5.2 --- Fourier Factorization Rules --- p.20 / Chapter 2.5.3 --- Matching Boundary Conditions --- p.21 / Chapter 2.5.4 --- Multilayered Gratings and Staircase Approximation --- p.25 / Chapter 2.5.5 --- Model Calculations --- p.25 / Chapter 2.6 --- Anisotropic Gratings --- p.26 / Chapter 2.6.1 --- General Form of Electromagnetic Modes --- p.29 / Chapter 2.6.2 --- Matching Boundary Conditions --- p.30 / Chapter 2.6.3 --- Model Calculations --- p.31 / Chapter 3 --- Grating Diffraction by Linear Superposition of Retarded Field --- p.33 / Chapter 3.1 --- Basic Ideas --- p.33 / Chapter 3.2 --- Formalism --- p.35 / Chapter 3.2.1 --- Field Induced Currents --- p.36 / Chapter 3.2.2 --- Field due to Current and Charge Densities --- p.38 / Chapter 3.2.3 --- "Internal, Transmitted, and Reflected Fields" --- p.39 / Chapter 3.2.4 --- Points of Physical Interest --- p.41 / Chapter 3.3 --- Model Calculations --- p.43 / Chapter 3.4 --- Application to Systems with Anisotropy or Nonlinearity --- p.46 / Chapter 3.5 --- Summary --- p.52 / Chapter 4 --- Introduction to Surface Plasmonic Excitations and Phenomenon of Enhanced Transmission --- p.55 / Chapter 4.1 --- Introduction to Surface Plasmons --- p.55 / Chapter 4.2 --- Phenomenon of Enhanced Transmission --- p.60 / Chapter 5 --- Enhanced Transmission Through Stacking Grating with Subwavelength Slits --- p.72 / Chapter 6 --- Controlling Enhanced Transmissions via Anisotropic Effects --- p.81 / Chapter 6.1 --- Effects of Anisotropic Waveguide on The Phenomenon of Enhanced Transmission --- p.82 / Chapter 6.1.1 --- Control of Enhanced Transmission by Anisotropic Waveguide --- p.83 / Chapter 6.1.2 --- Electromagnetic Modes in Anisotropic Waveguide --- p.87 / Chapter 6.1.3 --- Single Mode Model for Studying Transmission of Grating with Slits Filled with Anisotropic Material --- p.89 / Chapter 6.2 --- Effects of Strong Applied Magnetic Field on the Phenomenon of Enhanced Transmission --- p.95 / Chapter 6.2.1 --- Magnetic Field Induced Anisotropy in Metals --- p.95 / Chapter 6.2.2 --- Enhanced Transmission under Influence of Strong Magnetic Field --- p.97 / Chapter 6.2.3 --- Modification of Surface Plasmon Dispersion relation by Strong Applied Magnetic Field --- p.101 / Chapter 7 --- Conclusion --- p.107 / Bibliography --- p.111 / Chapter A --- Fourier Factorization Rules --- p.120 / Chapter A.l --- Notations --- p.120 / Chapter A.2 --- Factorization rules [28] --- p.121 / Chapter A.3 --- Fourier Factorization of Quantities in Anisotropic medium [32] --- p.122 / Chapter B --- Derivation of Integral in Eq. (3.10) --- p.124

"The objective of this project was to extend fundamentally the current kp theory by applying the Burt-Foreman formalism, rather than the conventional Luttinger-Kohn formalism, to a number of novel nanostructure geometries. The theory itself was extended in two ways. First in the application of the Burt-Foreman theory to computing the momentum matrix elements. Second in the development of a new formulation of the multiband kp Hamiltonian describing cylindrical quantum dots. A number of new and interesting results have been obtained. The computational implementation using the finite difference method of the Burt-Foreman theory for two dimensional nanostructures has confirmed that a non-uniform grid is much more efficient, as had been obtained by others in one dimensional nanostructures. In addition we have demonstrated that the multiband problem can be very effectively and efficiently solved with commercial software (FEMLAB). Two of the most important physical results obtained and discussed in the dissertation are the following. One is the first ab initio demonstration of possible electron localization in a nanowire superlattice in a barrier material, using a full numerical solution to the one band kp equation. The second is the demonstration of the exactness of the Sercel-Vahala transformation for cylindrical wurtzite nanostructures. Comparison of the subsequent calculations to experimental data on CdSe nanorods revealed the important role of the linear spin splitting term in the wurtzite valence band."

Friction stir processing (FSP), a solid-state post-processing technique that can provide localized modification and control of microstructures in near-surface layers of metallic components is developed based on the principles of friction stir welding (FSW). In this study, FSP was carried out in two phases. In Phase I, FSP was applied to one inch thick, sand casting A206 aluminum and 0.25 inch A367 bending fatigue sample. Optical microscope, SEM and EDS measurements have been performed to reveal a homogenous microstructure in the stirred zone, in which the porosities were quantitatively reduced, the second phase particles have been broken up and distributed in the Al matrix and there were some new components generated. Thermocouples have been applied to acquire the temperature gradient and thermo history during FSP. A range of material properties, including hardness and tensile measurement in A206, and bending fatigue test in A367 were examined. FSP resulted in an increase in hardness of the nugget compared to the hardness profile of the T4 condition. A significant improvement of the ductility of A206 was found after FSP compared to the ductility of T4 A206, but the FSP process slightly reduced the strength of A206. In Phase II, FSP was used for composite fabrication in the top layer of A206 substrate. The discontinuously reinforced aluminum (DRA) which contained 15% weight percent SiC was introduced into one inch thick sand cast A206 substrate. The surface composite layer is well bonded to the aluminum alloy substrate. Defects were not visible validating that FSP is an effective way for composite fabrication in Al cast alloys.

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No description available.

Tsang Sai-wing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references. / Abstracts in English and Chinese. / ABSTRACT (ENGLISH) --- p.I / ABSTRACT (CHINESE) --- p.III / ACKNOWLEDGEMENTS --- p.IV / TABLE OF CONTENTS --- p.V / Chapter 1. --- INTRODUCTION --- p.1 / Chapter 2. --- ELECTRONIC STRUCTURE OF ORGANIC SEMICONDUCTORS --- p.6 / Chapter 2.1 --- Introduction of energy-band diagram in organic semiconductors --- p.7 / Chapter 2.1.1 --- Organic semiconductors --- p.7 / Chapter 2.1.2 --- Density of state (DOS) and traps distribution --- p.8 / Chapter 2.1.3 --- Metal/organic interface --- p.10 / Chapter 2.1.4 --- Surface morphology and crystallinity of organic semiconductors --- p.12 / Chapter 2.2 --- Experimental --- p.14 / Chapter 2.2.1 --- Experimental scheme --- p.14 / Chapter 2.2.2 --- Sample preparation --- p.14 / Chapter 2.3 --- Data analysis and discussions --- p.15 / Chapter 2.3.1 --- Surface morphology on substrate temperature effect --- p.15 / Chapter 2.3.2 --- Characteristics of trap in CuPc thin film --- p.19 / Chapter 2.4 --- Conclusions --- p.20 / Reference --- p.22 / Chapter 3. --- CHARGE TRANSPORT IN CuPc ORGANIC SEMICONDUCTORS --- p.25 / Chapter 3.1 --- Introduction --- p.26 / Chapter 3.1.1 --- Carrier injection at metal-organic interface --- p.26 / Chapter 3.1.2 --- Carrier transport in organic semiconductors --- p.28 / Chapter 3.1.2.1 --- Polaron models --- p.29 / Chapter 3.1.2.2 --- Scher-Montroll model - Anomalous dispersive transport --- p.29 / Chapter 3.1.2.3 --- Gaussian disorder model --- p.32 / Chapter 3.2 --- Experimental / Chapter 3.2.1 --- Experimental scheme --- p.35 / Chapter 3.2.2 --- Sample preparation --- p.35 / Chapter 3.2.3 --- Admittance spectroscopy --- p.35 / Chapter 3.2.4 --- Dark injection space-charge-limited transient current measurement --- p.39 / Chapter 3.3 --- Results and discussions --- p.41 / Chapter 3.3.1 --- Simulation results of admittance spectroscopy --- p.41 / Chapter 3.3.2 --- Experimental results of Au/CuPc/Au devices by admittance spectroscopy --- p.49 / Chapter 3.3.2.1 --- Field dependent hole mobility of CuPc --- p.49 / Chapter 3.3.2.2 --- Thickness dependent dispersive transport --- p.53 / Chapter 3.3.3 --- Experimental results of Au/CuPc/Au devices by dark-injection space-charge-limited transient current measurement --- p.55 / Chapter 3.4 --- Conclusions --- p.58 / Reference --- p.59 / Chapter 4. --- NEGATIVE CAPACITANCE IN AU/CUPC/AU DEVICES --- p.61 / Chapter 4.1 --- Introduction of negative capacitance in different material systems --- p.62 / Chapter 4.2 --- Experimental --- p.63 / Chapter 4.2.1 --- Experimental scheme --- p.63 / Chapter 4.2.2 --- Sample preparation --- p.63 / Chapter 4.3 --- Data analysis and discussions --- p.64 / Chapter 4.4 --- Conclusions --- p.70 / Reference --- p.71 / Chapter 5. --- HOLE TRANSPORT IN COPPER PHTHALOCYANNINE UNDER VARIOUS AMBIENT CONDITIONS --- p.72 / Chapter 5.1 --- Introduction --- p.73 / Chapter 5.1.1 --- Current development of organic sensors --- p.73 / Chapter 5.1.2 --- Underlying mechanisms in sensing applications --- p.74 / Chapter 5.2 --- Experimental --- p.76 / Chapter 5.2.1 --- Experimental scheme --- p.76 / Chapter 5.2.2 --- Sample preparation --- p.77 / Chapter 5.3 --- Data analysis and discussions --- p.78 / Chapter 5.4 --- Conclusions --- p.83 / Reference --- p.84 / Chapter 6. --- SUMMARY AND FUTURE WORK --- p.85 / Summary --- p.85 / Future work --- p.87 / APPENDIX A: derivation of complex admittance --- p.89 / APPENDIX B: derivation of transient relaxation current --- p.92 / APPENDIX C: simulation for admittance spectroscopy --- p.95 / APPENDIX D: publications which contributed to this thesis --- p.99

Kwok Tsun Ah Joseph = 界面及梯度物料的介電性質的研究 / 郭俊雅. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 59-64). / Text in English; abstracts in English and Chinese. / Kwok Tsun Ah Joseph = Jie mian ji ti du wu liao de jie dian xing zhi de yan jiu / Guo Junya. / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- A Review of Composite Materials --- p.1 / Chapter 1.2 --- Graded Colloidal Crystals --- p.4 / Chapter 1.3 --- Long Range Interaction and Local Field Distribution --- p.6 / Chapter 1.4 --- Objective of the Thesis --- p.8 / Chapter 2 --- Local Field Determination in Bulk Periodic Systems --- p.10 / Chapter 2.1 --- Handling the Long Range Interaction --- p.10 / Chapter 2.1.1 --- The Three-dimensional Ewald Summation (EW3D) --- p.10 / Chapter 2.1.2 --- The Two-dimensional Ewald Summation (EW2D) --- p.13 / Chapter 2.1.3 --- The Lekner Summation --- p.14 / Chapter 2.2 --- Local Field Theory --- p.17 / Chapter 2.3 --- Results and Discussion --- p.19 / Chapter 2.4 --- Conclusion --- p.23 / Chapter 3 --- Multi-layer Formulation and Local Field Calculation --- p.26 / Chapter 3.1 --- A Model System --- p.26 / Chapter 3.2 --- Interlayer Interaction --- p.28 / Chapter 3.3 --- Multilayer Self-consistent Formalism --- p.30 / Chapter 3.4 --- Summary --- p.31 / Chapter 4 --- Optical Response of Graded Materials and Interfaces --- p.33 / Chapter 4.1 --- Constructing Graded Colloidal Crystals --- p.33 / Chapter 4.1.1 --- Coated Metallic Spheres --- p.34 / Chapter 4.1.2 --- Drude Dielectric Gradation Profiles --- p.35 / Chapter 4.2 --- Results and Discussion --- p.36 / Chapter 4.2.1 --- Optical Absorption of Graded Colloidal Crystals of Different Structures --- p.36 / Chapter 4.2.2 --- Optical Absorption of Colloidal Interfaces --- p.44 / Chapter 4.2.3 --- Graded Spherical Colloids in Dimer-arrays --- p.49 / Chapter 4.3 --- Other Kinds of Graded Colloidal Crystals and Interfaces --- p.51 / Chapter 4.3.1 --- Coated or Multi-coated Spherical Colloidal Crystals --- p.51 / Chapter 4.3.2 --- Coated Colloidal Crystals with a Radii-Gradient in the Cores --- p.52 / Chapter 4.3.3 --- Composites of Inclusions Other than Spheres --- p.53 / Chapter 4.3.4 --- Hairy interfaces --- p.53 / Chapter 4.4 --- Summary --- p.54 / Chapter 5 --- Conclusion --- p.57 / Bibliography --- p.59 / Chapter A --- Useful Expressions for the Lekner Summation Method --- p.65 / Chapter B --- Lorentz Cavity --- p.68 / Chapter C --- Two Mathematical Proofs --- p.70 / Chapter C.1 --- Proof of Tk『=Tk =-2Tkzz --- p.70 / Chapter C.2 --- Proof of the Sum Rule of Σk=-NTk = 4π for Large N in a Simple Cubic Structure --- p.71 / Chapter D --- The Ewald-Kornfeld Formulation --- p.74

石墨烯具有獨特的電學,熱力學及機械性能,在科學研究和技術領域受到廣泛的關注。特別是,以石墨烯為基礎的石墨烯場效應電晶體近年來得到了快速發展,使其成為後矽基時代的可選用材料之一。不同于傳統的體半導體材料,石墨烯具有獨特的二維結構;它與周圍環境的介面相互作用對石墨烯器件有決定性的影響。研究石墨烯的介面特性在石墨烯應用中具有重要的意義。因此研究者對於發掘在納米尺度上的石墨烯介面規律及由此獨特的介面特性所導致的電子結構、載流子輸運性質和其他相關現象具有濃厚的興趣。在本論文中,我們從實驗和理論兩個方面對石墨烯與不同基底的介面耦合機制,由金屬電極到石墨烯的電荷注入以及其表面的吸附物對石墨烯的摻雜作用進行了深入细致的研究。 / 首先,通過對薄層石墨烯的表面功能化,可以對其電子結構進行有效的控制和調整。在石墨烯薄片表面吸附不同的自組裝有機分子,可以實現對石墨烯的電子和空穴摻雜。另外,我們對由電子束放射產生的摻雜效應也進行了研究。我們發現當利用電子束處理包含不同層數的石墨烯薄片時,可以形成石墨烯pn結。 其次,我們對石墨烯基底對於石墨烯的重要作用進行了深入的探究。由於商用矽片中存在的帶電雜質及石墨烯褶皺對放置於其上的石墨烯樣品產生了極大的影響,使得石墨烯的遷移率遠小於其理論值。為消弱由基底產生的不利影響,我們利用自組裝單分子膜對二氧化矽/矽襯底的表面進行鈍化處理,從而減少不必要的散射。通過鈍化處理,載流子遷移率上升了近一個數量級(達到 47,000 cm²/Vs)。 / 此外,我們對石墨烯與不同金屬電極接觸的介面電學性質也進行了系統研究。我們發現較低的電阻及線性的電流電壓關係對於石墨烯場效應電晶體並非始終成立。對於本征石墨烯,我們發現石墨烯和金屬電極的接觸具有‘空間電荷區限制’和‘歐姆接觸’兩種接觸模式。並且在偏置電壓控制下,接觸電阻可以可逆的在兩種接觸模式中切換。我們發現該現象可以歸結于石墨烯獨特的錐型能帶色散關係。該現象提供了新的製備高密度非易失性石墨烯記憶體的方法。 / Graphene is an appealing material in both science and technology. Its distinct electronic, thermal and mechanical properties have stimulated enormous scientific interest. In particular, graphene-based field-effect transistors (GFET) have been developed rapidly and are now considered an option for post-silicon electronics. In contrast to traditional semiconductors, the unique two dimensional structure of graphene offers the possibility of studying the interface characteristics for its proximity to the top surface and interface between graphene and the outside environment. We are thus interested in understanding graphene surface and interfacial issues associated with electronic structure, carrier transport and related phenomena on a nano-scale. In this thesis, we investigate both experimentally and theoretically the mechanisms of graphene interfacial couplings to different substrates, charge injection from metal electrodes and its interplay with inert adsorbates. / At first, few layer graphene’s (FLG) electronic properties are adjusted efficiently and controllably through functionalizing its top surface. Both n-type and p-type doped exfoliated graphene sheets are present by virtue of adsorbing organic molecules. Additionally, the doping effects induced by electron beam (EB) irradiation are also studied. We find that by irradiating graphene with EB, graphene p-n junctions can be formed if EB irradiation is applied across a single graphene sheet containing regions with different layers. / Secondly, the crucial roles played by the supported substrate in graphene applications are meticulously interrogated. The existence of charge impurities and ripples adversely affects the mobility of high quality mechanically exfoliated graphene on commercially available SiO₂/Si wafers inferior to its theoretical limit. To suppress the deleterious substrate effect, we utilize self-assembled monolayers to passivate the SiO₂/Si substrate surface. After diminishing the unwanted scattering origins by this method, an increase in carrier mobility by nearly one order of magnitude (up to 47,000 cm²/Vs) is obtained. / Furthermore, the electronic properties of the interfaces between graphene and various metal electrodes are systematically investigated. Our study unambiguously reveals that a low electrical resistance as well as a linear current-voltage relation is not always granted for GFETs. Interestingly, for graphene on SiO₂/Si passivated with highly-ordered OTMS, both ‘space charge region limited’ and ‘ohmic’ contacts can be obtained with a single metal electrode. We also find that by utilizing voltage bias, the contact can be reversibly altered between high resistance and low resistance. We ascribe the phenomenon to graphene’s cone energy dispersion relationship as well as the vanishing density of states at the Dirac points. Our results herald a new avenue for achieving high density non-volatile graphene memory devices. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Wang, Xiaomu. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references. / Abstract also in Chinese. / Abstracts in English and Chinese. / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Electronic Properties of Graphene --- p.1 / Chapter 1.1.1 --- Graphene Band Structure --- p.1 / Chapter 1.1.2 --- Physical Properties of Graphene --- p.4 / Chapter 1.1.3 --- Carrier Transport in Graphene --- p.7 / Chapter 1.1.4 --- Optical Properties of Graphene --- p.9 / Chapter 1.2 --- Motivation and Outline of the Thesis --- p.10 / Chapter 1.2.1 --- Graphene Field-Effect Transistors --- p.10 / Chapter 1.2.2 --- Interface Engineering --- p.15 / Chapter Chapter 2 --- Sample Preparation Details and Characterization Techniques --- p.26 / Chapter 2.1 --- Graphene Preparation --- p.26 / Chapter 2.1.1 --- Mechanical Exfoliation --- p.26 / Chapter 2.1.2 --- Reduced Graphite Oxide --- p.28 / Chapter 2.1.3 --- Graphene Synthesis by CVD on Copper Substrates --- p.28 / Chapter 2.2 --- Characterization of Graphene --- p.29 / Chapter 2.2.1 --- Optical Microscopy --- p.30 / Chapter 2.2.2 --- Raman Spectroscopy --- p.30 / Chapter 2.2.3 --- Scanning Probe Microscopic Techniques --- p.32 / Chapter 2.3 --- GFET Fabrication --- p.33 / Chapter 2.3.1 --- Photolithography Process --- p.34 / Chapter 2.3.2 --- Shadow Mask Method Process --- p.34 / Chapter 2.3.3 --- Lithography-Free Process --- p.35 / Chapter Chapter 3 --- Top Surface Modification of Graphene --- p.37 / Chapter 3.1 --- Charge Transfer by Organic Molecules in Doping of Graphene --- p.37 / Chapter 3.1.1 --- Overview --- p.37 / Chapter 3.1.2 --- Kelvin Probe Force Microscopy --- p.41 / Chapter 3.1.3 --- Experimental Details --- p.45 / Chapter 3.1.4 --- P-type Doping of Graphene by F4-TCNQ --- p.47 / Chapter 3.1.5 --- N-tpye Doping of Graphene by VOPc --- p.48 / Chapter 3.1.6 --- Mechanism of Charge Transfer: A Quantitative Analysis --- p.55 / Chapter 3.2 --- Asymmetric Doping of Graphene by Electron Beam Irradiation --- p.66 / Chapter 3.2.1 --- Overview --- p.66 / Chapter 3.2.2 --- Experimental Details --- p.67 / Chapter 3.2.3 --- Transport Measurements --- p.70 / Chapter 3.3 --- Summary --- p.73 / Chapter Chapter 4 --- Substrate Modification for Graphene --- p.81 / Chapter 4.1 --- Substrate Effects Adjusted by Thermal Annealing --- p.81 / Chapter 4.1.1 --- Overview --- p.81 / Chapter 4.1.2 --- Experimental Details --- p.82 / Chapter 4.1.3 --- Mechanism of Graphene/Substrate Interaction --- p.84 / Chapter 4.2 --- Modified Substrate by Highly Ordered OTMS SAMs --- p.85 / Chapter 4.2.1 --- Overview --- p.85 / Chapter 4.2.2 --- Experimental Details --- p.87 / Chapter 4.2.3 --- Transport Measurements --- p.94 / Chapter 4.2.4 --- Summary --- p.111 / Chapter Chapter 5 --- Graphene/Metal Contacts --- p.116 / Chapter 5.1 --- Graphene/Metal Contacts --- p.116 / Chapter 5.1.1 --- Overview --- p.116 / Chapter 5.1.2 --- Experimental Details --- p.118 / Chapter 5.2 --- Contact Modes and Related Memory Devices --- p.125 / Chapter 5.2.1 --- Bistable Contact Modes --- p.125 / Chapter 5.2.2 --- Related Memory Devices --- p.132 / Chapter 5.2.3 --- Contact Mechanism --- p.136 / Chapter 5.3 --- Transport Mechanism for OFF States --- p.147 / Chapter 5.3.1 --- Temperature-Dependent Transport Measurements --- p.148 / Chapter 5.3.2 --- WKB Approximations --- p.151 / Chapter 5.3.3 --- Tunneling between Fermi Liquid and Luttinger Liquid --- p.154 / Chapter 5.4 --- Summary --- p.156 / Chapter Chapter 6 --- Conclusions and Outlook --- p.161 / Chapter 6.1 --- Major Findings and Summary --- p.161 / Chapter 6.2 --- Outlook for Future Research --- p.165 / Chapter Appendix A --- Transport Model of GFET --- p.169 / Chapter A.1 --- Transport Models --- p.169 / Chapter A.2 --- Drift Current Model --- p.171 / Chapter A.3 --- Quantum Transport Theory of GFET --- p.175 / Chapter A.4 --- Brief Outline of NEGF --- p.177

Zhuang, Junping = 單根納米線的軸向局域的光學性質 / 庄俊平. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references. / Abstracts in English and Chinese. / Zhuang, Junping = Dan gen na mi xian de zhu xiang ju yu de guang xue xing zhi / Zhuang Junping. / Acknowledgement --- p.I / Abstract --- p.II / 摘要 --- p.IV / Contents --- p.i / List of Figures --- p.iv / List of Tables --- p.viii / Abbreviations --- p.ix / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.2 --- ZnSe Semiconductor Nanowires --- p.2 / Chapter 1.3 --- Carrier Dynamics in Semiconductor Nanowires --- p.3 / Chapter 1.3.1 --- Carrier Relaxation --- p.3 / Chapter 1.3.2 --- Surface Effects on Carrier Recombination --- p.7 / Chapter 1.4 --- Principle ofTCSPC Technique --- p.9 / Chapter 1.5 --- Motivations and Works --- p.10 / References --- p.12 / Chapter Chapter 2 --- Experiments --- p.17 / Chapter 2.1 --- Growth of ZnSe Nanowires --- p.17 / Chapter 2.2 --- Measurements with Electron Microscopes --- p.17 / Chapter 2.3 --- Measurements by a Laser Scanning Microscope --- p.18 / Chapter 2.3.1 --- Experimental Setup --- p.18 / Chapter 2.3.2 --- Settings of Measurements --- p.23 / References --- p.25 / Chapter Chapter 3 --- Methods of Analysis --- p.26 / Chapter 3.1 --- Luminescence Intensity --- p.26 / Chapter 3.1.1 --- Intensity Detected by PMT --- p.27 / Chapter 3.1.2 --- Intensity Detected by SPAD --- p.28 / Chapter 3.2 --- Lifetime Histogram --- p.29 / Chapter 3.2.1 --- Pixel Binning --- p.29 / Chapter 3.2.2 --- Lifetime Fitting --- p.32 / References --- p.33 / Chapter Chapter 4 --- Results and Discussion --- p.34 / Chapter 4.1 --- "Morphology, Structure and Composition of As-Grown Nanowires" --- p.34 / Chapter 4.2 --- Cathodoluminescence of Individual ZnSe Nanowires --- p.36 / Chapter 4.3 --- Photoluminescence of ZnSe Nanowires --- p.36 / Chapter 4.4 --- Luminescence of Individual Nanowires --- p.39 / Chapter 4.4.1 --- Luminescence of As-Grown Nanowires --- p.39 / Chapter 4.4.2 --- Nonlinear Optical Properties --- p.42 / Chapter 4.5 --- Luminescence Lifetimes of Individual Nanowires --- p.47 / Chapter 4.5.1 --- Power Dependence --- p.48 / Chapter 4.5.2 --- Chemical Environments --- p.53 / Chapter 4.5.3 --- Concentration of Ammonium Sulfide Solution --- p.56 / Chapter 4.6 --- Axially Resolved Luminescence Lifetimes --- p.60 / Chapter 4.6.1 --- Axially Resolved 2D Decay Diagrams --- p.60 / Chapter 4.6.2 --- Axially Resolved Luminescence Lifetimes --- p.62 / Chapter 4.6.3 --- (TNBE) and T1 of DL Emission --- p.69 / References --- p.72 / Chapter Chapter 5 --- Conclusions --- p.76 / Appendix A --- p.79 / Chapter A.1 --- Laser Beam Diameter and Spatial Resolution --- p.79 / Chapter A.2 --- Instrument Response Function of TCSPC module --- p.81 / Chapter A.3 --- Photo-Injection --- p.82 / Chapter A.3.1 --- Two-Photon Excitation by Pulse Laser --- p.82 / Chapter A.3.2 --- One-Photon Excitation by CW UV Laser --- p.84 / Chapter A.4 --- Lifetime Distributions --- p.85 / References --- p.86 / Appendix B Supporting Data --- p.87

A research report submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg in partial fulfilment of the requirements for the degree of Master of Science / The aim of this work was to evaluate the measurement of the optical properties as a means of obtaining information on the growth history of synthetic diamond. A suite of sample of known synthesis origin representing the different types of commercially produced synthetic diamond was analysed hy photoluminescence. The photoh.{fnmescence intensity was normalising by using the area of tbe Raman peak. This allowed a semi-quantitative comparison of the defect concentration. Three photoluminescent centres were identified, H3, 575 run and 1.945 eV (with zero-phonon lines at 2.463 eV, 2.156 eV, and 1.945 eV respectively). Differences between the intensities of the luminescence due to these centres were observed as a function of the type ot diamond The H3 amd the 1.945 eV intensity was found to increase with the proportion of cubic growth sector, In addition the 1.945 eV intensity was found to increase with heat treatment and was higher in (100) than in (111) growth sectors. As all three defects detected involve vacancies and nitrogen impurity, an analysis was done to quantify any correlation between the luminescent intensities from the different defects in the same SDA powder sample. The 1.945 eV and 575 run intensities were observed to be correlated .. An additional correlation 'was found between the 575 lim and the H3 intensities in the case of finer particle size samples. The luminescence intensity for all three defect types was observed to be a function of the particle size of the sample. The shapes and widths of zero-phonon lines were related to the types and concentration of lattice defects present in a crystal according to line broadening theory. An attempt was made to explain the results in the context of the known synthesis origin and growth conditions. / AC 2018