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LSU Doctoral Dissertations

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Essays On The Bayesian Estimation Of Stochastic Cost Frontier, Xia Zhao Jan 2006

Essays On The Bayesian Estimation Of Stochastic Cost Frontier, Xia Zhao

LSU Doctoral Dissertations

This dissertation consists of three essays that focus on a Bayesian estimation of stochastic cost frontiers for electric generation plants. This research gives insight into the changing development of the electric generation market and could serve to inform both private investment and public policy decisions. The main contributions to the growing literature on stochastic cost frontier analysis are to 1. Empirically estimate the possible efficiency gain of power plants due to deregulation. 2. Estimate the cost of electric power generating plants using coal as a fuel taking into account both regularity restrictions and sulfur dioxide emissions. 3. Compare costs of …

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A Distribution Kinetics Approach For Polymer Crystallization And Phase Separation, Jiao Yang Jan 2006

A Distribution Kinetics Approach For Polymer Crystallization And Phase Separation, Jiao Yang

LSU Doctoral Dissertations

The mechanism of polymer crystallization is extensively studied and still far away from consensus. This research adopted cluster size distribution kinetics approach to explore the kinetics of polymer crystallization and phase separation within spinodal region. The kinetics of polymer crystallization is studied by integrating nucleation, crystal growth and ripening. Population balance equations based on crystal size distribution and concentration of amorphous polymer segments are solved numerically and the related differential moment equations are also solved. The model accounts for nucleation and crystal growth. Different mass dependences of growth and dissociation rate coefficients are proposed to investigate the fundamental features of …

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Infrared Laser Desorption/Ionization Mass Spectrometry: Fundamental And Applications, Mark Little Jan 2006

Infrared Laser Desorption/Ionization Mass Spectrometry: Fundamental And Applications, Mark Little

LSU Doctoral Dissertations

This dissertation on infrared laser desorption/ionization mass spectrometry encompasses fundamental studies of the desorption/ionization process and direct-from-gel laser desorption/ionization applications. Understanding of the fundamentals behind desorption and ionization can lead to improvements in the technique and to new applications. Experiments aimed at advancing this goal are wavelength studies and two-laser infrared/ultraviolet matrix-assisted laser desorption/ionization experiments. The direct-from-gel laser desorption/ionization application in which infrared laser desorption/ionization of analytes directly ionized after gel electrophoretic separation will also be presented. Protein and peptide standards were used as test analytes and the infrared lasers used were a 10.6 micrometers carbon-dioxide laser and a mid-IR …

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Synthesis, Crystal Growth, Magnetic And Transport Properties Of Ln-M-X (Ln=Lanthanide, M=Transition Metal, X=In, Ga) Compounds, Willa Maria Williams Jan 2006

Synthesis, Crystal Growth, Magnetic And Transport Properties Of Ln-M-X (Ln=Lanthanide, M=Transition Metal, X=In, Ga) Compounds, Willa Maria Williams

LSU Doctoral Dissertations

ABSTRACT This dissertation focuses on the structural stability, magnetic and transport properties of ternary lanthanide compounds grown using indium and gallium flux. Single crystals of TbRhIn5 were synthesized using indium flux. TbRhIn5 is isostructural to the well known LnnMIn3n+2 (n = 1, 2, ∞; Ln = La, Ce; M = Rh, Ir) and adopts the HoCoGa5 structure type and crystallizes in the space group P4/mmm, Z = 1. Lattice parameters are a = 4.6000(6) Å and c = 7.4370(11) Å, V = 157.29(6) Å3. A sharp antiferromagnetic transition is observed at TN = 48 K for TbRhIn5. Single crystals of …

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Heroic Individualism: The Hero As Author In Democratic Culture, Alan I. Baily Jan 2006

Heroic Individualism: The Hero As Author In Democratic Culture, Alan I. Baily

LSU Doctoral Dissertations

My study focuses on the literature of democratic morality, with specific reference to the question of "heroic individualism." I attempt to elucidate the notion of heroic individualism by examining three modern democratic moralists whose work occupies the space between politics and literature: Jean Jacques Rousseau, Thomas Carlyle and Friedrich Nietzsche. In brief, I conclude that the central aspiration of heroic individualism is to bridge the gap between writing and action, the Text and the Voice. The dialogue among Rousseau, Carlyle, and Nietzsche reveals that the problem of writing as action is central to heroic-individualist morality. Each of these authors demonstrates …

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Topics In Quantum Topology, Khaled Moham Qazaqzeh Jan 2006

Topics In Quantum Topology, Khaled Moham Qazaqzeh

LSU Doctoral Dissertations

In chapter 1, which represents joint work with Gilmer, we define an index two subcategory of a 3-dimensional cobordism category. The objects of the category are surfaces equipped with Lagrangian subspaces of their real first homology. This generalizes the result of [9] where surfaces are equipped with Lagrangian subspaces of their rational first homology. To define such subcategory, we give a formula for the parity of the Maslov index of a triple of Lagrangian subspaces of a skew symmetric bilinear form over R. In chapter 2, we find two bases for the lattices of the SU(2)-TQFT-theory modules of the torus …

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Reflections On Teaching A Mathematics Education Course, Sarah Elizabeth Smitherman Jan 2006

Reflections On Teaching A Mathematics Education Course, Sarah Elizabeth Smitherman

LSU Doctoral Dissertations

Teaching and learning involve reflexive actions and should be chosen thoughtfully and deliberately, not because someone has decided “what works.” In this study, I examine how complex conversations might offer pedagogical and theoretical (re)considerations in a teacher education course on mathematics. The term “math methods” is a doubly weighted phrase, for both mathematics and methods connote particular ideologies prevalent in current educational rhetoric. In order to unpack the impact of these words, I engage in research based on inquiry, historical analysis, and personal reflections, all of which I use in an eclectic, thoughtful, and explorative manner. The two main research …

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Loading And Recovery Behavior Of The Human Lumbar Spine Under Static Flexion, Guntulu Selen Hatipkarasulu Jan 2006

Loading And Recovery Behavior Of The Human Lumbar Spine Under Static Flexion, Guntulu Selen Hatipkarasulu

LSU Doctoral Dissertations

Musculoskeletal disorders account for 32 percent of work related injuries and illnesses. Extensive studies have been conducted to understand and explore the factors that affect the development of musculoskeletal disorders to provide effective control strategies. One of the most important factors that allow effective control strategies is the biomechanical factors. Among the biomechanical risk factors, exposures to repetitive static and vibratory activities are known to result in musculoskeletal disorders. A ligamento–muscular reflex activity exists in humans and animals to stabilize the knee, shoulder, elbow, ankle joints, and spine. This reflex activity decreases over time when static loading is applied, which …

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Detecting The Socioeconomic Conditions Of Urban Neighborhoods Through Wavelet Analysis Of Remotely Sensed Imagery, Guiyun Zhou Jan 2006

Detecting The Socioeconomic Conditions Of Urban Neighborhoods Through Wavelet Analysis Of Remotely Sensed Imagery, Guiyun Zhou

LSU Doctoral Dissertations

Wavelet analysis is an efficient approach to studying textural patterns at different scales. Artificial neural networks can learn very complex patterns in the data and could be an efficient classifier. However, whether wavelet analysis, in combination with artificial neural networks or other classifiers, can be used to detect the social-economic conditions of urban neighborhood is a key research question that needs further study. The hypotheses of this study were: 1) neural networks yielded higher classification accuracy than linear discriminant analysis and the minimum-distance classifier based on wavelet measures of urban land covers; 2) wavelet textural measures could be used to …

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Louisiana Cotton, Rice, Soybean And Sugarcane Farmer Stakeholders: Who Are They And What Are Their Perceptions Of Farming Practices As Related To The Environment, Robert James Soileau Jan 2006

Louisiana Cotton, Rice, Soybean And Sugarcane Farmer Stakeholders: Who Are They And What Are Their Perceptions Of Farming Practices As Related To The Environment, Robert James Soileau

LSU Doctoral Dissertations

This study identified the stakeholders of Louisiana plant commodity farmers and rated them in terms of importance. Findings of this study show that farmers/ranchers, LSU AgCenter Experiment Station Research personnel, family, consumers, farm labor and agriculture chemical, fertilizer and seed dealers are the most important stakeholders. The second aspect of this study was to discover the stakeholder perceptions of agricultural practices and their relationship to the environment. An environmental perceptions survey was conducted with two of the most important stakeholder groups identified – Experiment Station Research Faculty associated with plant commodities and Louisiana consumers. LSU AgCenter Experiment Station Research Faculty …

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Evaluating Preference For Reinforcers Under Varying Schedule Requirements In Children With Developmental Disabilities, Tiffany Michelle Kodak Jan 2006

Evaluating Preference For Reinforcers Under Varying Schedule Requirements In Children With Developmental Disabilities, Tiffany Michelle Kodak

LSU Doctoral Dissertations

Previous research has shown that preference for concurrently available reinforcers can be influenced by the reinforcement schedule (DeLeon, Neidert, Anders, & Rodriguez-Catter, 2001; Tustin, 1994). However, limited research has been conducted on specific variables that may influence preference under various schedule requirements. The present study evaluated the influence of task preference, schedule, and quality of reinforcement on choice between either an arbitrary reinforcer or a functional reinforcer. Five participants diagnosed with Autism participated in the study. In the first phase, we evaluated the effects of task preference and schedule of reinforcement on choice between a 30-s break and a high …

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Say It Loud! I'M Black And I'M Proud!: A Study Of Successful Black Female Students Educated In An Urban Middle School, Menthia P. Clark Jan 2006

Say It Loud! I'M Black And I'M Proud!: A Study Of Successful Black Female Students Educated In An Urban Middle School, Menthia P. Clark

LSU Doctoral Dissertations

"Acting White" (Fordham & Ogbu, 1986) is a common term among researchers who study academic achievement and racial identity among minority students which signifies the tension some academically successful minority students experience as they excel in school. Black students who contend with such tension may be teased, alienated, or rejected by their peers who view academic achievement as characteristic of White people. In order to avoid the accusation of "acting White," many Black students underachieve, conceal their academic talents, or make no efforts to pursue academic goals. For Black female high-achieving students, "acting White" is laden with gender-specific strategies of …

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On Moment Conditions For The Girsanov Theorem, See Keong Lee Jan 2006

On Moment Conditions For The Girsanov Theorem, See Keong Lee

LSU Doctoral Dissertations

In this dissertation, the well-known Girsanov Theorem will be proved under a set of moment conditions on exponential processes. Our conditions are motivated by the desire to avoid using the local martingale theory in the proof of the Girsanov Theorem. Namely, we will only use the martingale theory to prove the Girsanov Theorem. Many sufficient conditions for the validity of the Girsanov Theorem have been found since the publication of the result by Girsanov in 1960. We will compare our conditions with some of these conditions. As an application of the Girsanov Theorem, we will show the nonexistence of an …

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Adaptive Scalable Protocols For Heterogeneous Wireless Networks, Vamsi Krishna Paruchuri Jan 2006

Adaptive Scalable Protocols For Heterogeneous Wireless Networks, Vamsi Krishna Paruchuri

LSU Doctoral Dissertations

The focus of this dissertation is to propose analytical models to study the impact of collisions and interference in heterogeneous wireless networks and propose simple scalable and lightweight protocols that use these models to adapt to network conditions thus increasing efficiency, decreasing energy consumption and prolonging network lifetime. The contributions of this dissertation are multifold and are summarized as follows: - Analytical models to study the impact of collisions and interference on both broadcast and unicast messages. These analytical models are incorporated into the proposed protocols to adapt to the prevailing network conditions to improve their performance. - Optimized Flooding …

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Nutrient Constraints On Plant Community Production And Organic Matter Accumulation Of Subtropical Floating Marshes, Guerry O., Jr. Holm Jr. Jan 2006

Nutrient Constraints On Plant Community Production And Organic Matter Accumulation Of Subtropical Floating Marshes, Guerry O., Jr. Holm Jr.

LSU Doctoral Dissertations

In the cycle of delta growth and decay, peat-forming wetlands span a time and space continuum. Later in the delta cycle, freshwater floating marshes become increasingly removed from external sediment subsidy and internal nutrient cycling controls plant productivity and organic matter accumulation. An interesting question is whether increased external nutrient loading can affect the basic processes that lead to peat formation—plant production and organic matter decomposition. I conducted several field studies to understand whether belowground organic matter accumulation and decomposition were affected with increased nutrient exposure; in addition, the plant community was monitored over three years. A laboratory soil respiration …

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Spectral Analysis Of Total Suspended Solids Mixtures For Solids Composition Determination, Curtis W. Sutherland Jan 2006

Spectral Analysis Of Total Suspended Solids Mixtures For Solids Composition Determination, Curtis W. Sutherland

LSU Doctoral Dissertations

Total Suspended Solids (TSS) analysis provides an initial and very basic measure for study and characterization of water quality. The present tedious procedures used for the identification of different solids constituents present in TSS and for the classification or insight into the origins of those solids are time-consuming and expensive. The research reported herein investigates the use of instrumental analysis using reflectance spectra of TSS as an attractive alternative to sufficiently characterize and identify TSS in a more rapid and economical method that could be used to study TSS transport and to identity TSS points of origin. For this investigative …

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Tropical Pyramids: Dung Beetle Richness, Abundance, And Biomass, Meghan Gabrielle Radtke Jan 2006

Tropical Pyramids: Dung Beetle Richness, Abundance, And Biomass, Meghan Gabrielle Radtke

LSU Doctoral Dissertations

Volume is a proxy for biomass in hard bodied arthropods (P < 0.0001). I constructed biomass-volume equations for Neotropical (P < 0.0001), temperate (P < 0.0001) and 12 Neotropical genera of scarabs, of which 11 were highly significant. The effect of short term (< 1 year) alcohol storage on volume was negligable. I found scarab volume on geologically old soils in the Amazon was one-third that of the geologically young Amazon (P < 0.0001). Species richness (P = 0.0002), Chao 1 (P = 0.0003), Fisher’s  (P = 0.008) and Margalef indices (P = 0.0003) were greater on young soils. Menhinick (P = 0.54), Simpson (P = 0.54) and rarefied species richness (P = 0.24), which correct for sample size differences, indicated no difference in diversity. Young Amazonian soils likely support a higher volume and abundance of scarabs than old soils, but diversity across Amazonia may be similar. I compared beta-diversity of scarab communities across Amazonia. Species rank-abundance curves did not differ among sites whereas volume-abundance distributions and volume-rank abundance curves indicated a larger range of scarab sizes in Brazil than Ecuador. At local levels (<62 km), communities were similar whereas at large distances (>1750 km), they were different. Differences between Brazil and Ecuador may be explained by varied soil age and productivity. I examined the effects of tropical forest fragmentation on scarabs, comparing my results with three other studies from the same site. Among 1, 10, and 100-ha fragments and continuous forest, I found two important trends; beetle biomass and species richness increased with fragment area per sampling effort. Comparing all four studies, diversity increased with fragment size, and by my rarefaction analyses, two studies demonstrated beetle volume increased with fragment size. …

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Population Boundaries And Gravitational-Wave Templates For Evolving White Dwarf Binaries, Ravi Kumar Kopparapu Jan 2006

Population Boundaries And Gravitational-Wave Templates For Evolving White Dwarf Binaries, Ravi Kumar Kopparapu

LSU Doctoral Dissertations

We present results from our analysis of double white dwarf (DWD) binary star systems in the inspiraling and mass-transfer stages of their evolution. Theoretical constraints on the properties of the white dwarf stars allow us to map out the DWD trajectories in the gravitational-wave amplitude-frequency domain and to identify population boundaries that define distinct sub-domains where inspiraling and/or mass-transferring systems will and will not be found. We identify for what subset of these populations it should be possible to measure frequency changes and, hence, directly follow orbit evolutions given the anticipated operational time of the proposed space-based gravitational-wave detector, LISA. …

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A Stochastic Mesoscopic Cell-Transmission Model For Operational Analysis Of Large-Scale Transportation Networks, Ciprian Danut Alecsandru Jan 2006

A Stochastic Mesoscopic Cell-Transmission Model For Operational Analysis Of Large-Scale Transportation Networks, Ciprian Danut Alecsandru

LSU Doctoral Dissertations

The cell transmission model (CTM), developed by Daganzo in 1994 was not fully exploited as an operations model for analysis of large-scale traffic networks. Because of its macroscopic / mesoscopic features, CTM offers calibration and computational advantages over microscopic models. This study presents a series of enhancements to the original form of CTM. These enhancements show potential to increase the model’s accuracy and realism of traffic flow representation. For example, topological enhancements and modifications to the flow advancing equation are introduced to allow variable cell lengths and non-discrete movements of vehicles between cells. In addition, implementation of lane-changing behavioral logics …

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Applications Of Titanium-Mediated Reductive Coupling And Cyclocarbonylation Reactions Toward Natural Product Synthesis, Maria A. Appeaning Jan 2006

Applications Of Titanium-Mediated Reductive Coupling And Cyclocarbonylation Reactions Toward Natural Product Synthesis, Maria A. Appeaning

LSU Doctoral Dissertations

Previous work in our laboratory has demonstrated not only a synthetic value of tandem reductive cyclization - carbonylation reactions in the preparation of complex molecules but also the interesting stereoselectivity observed therein. The first part of this work employs the titanium-mediated cyclocarbonylation of tethered dienals for the synthesis of prostaglandin analogues, in particular PGF2α and methyl jasmonate. Based on this hetero Pauson-Khand strategy, we have established an efficient racemic route to both the prostaglandin and the methyl jasmonate core skeletons. Moderate to excellent selectivities with regard to the hetero Pauson-Khand reaction were observed in both cases. The second part …

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How Cue-Dependent Is Memory?: Internal Reinstatement And Cueing Effects In Recognition And Source Memory, Jeffrey Joseph Starns Jan 2006

How Cue-Dependent Is Memory?: Internal Reinstatement And Cueing Effects In Recognition And Source Memory, Jeffrey Joseph Starns

LSU Doctoral Dissertations

This study explored the role of internal context reinstatement in masking the effects of external context cues on recognition and source memory. Participants studied words paired with pictures of male and female faces. Following the study phase, participants completed either a source test in which they decided whether each test word was studied with a male or female face (Experiments 1, 3, and 4) or a recognition test in which they decided whether each test word appeared in the study phase (Experiment 2). On selected trials, a studied face was reinstated at test to serve as a cue for the …

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Synthesis, Characterization And Properties Of Cooper(Ii) Beta-Diketonate Macrocycles, Sylvester Burton Jan 2006

Synthesis, Characterization And Properties Of Cooper(Ii) Beta-Diketonate Macrocycles, Sylvester Burton

LSU Doctoral Dissertations

This dissertation deals with the synthesis and properties of multidentate β-diketone ligands and their transition-metal complexes. (1) We prepared two bis(β-diketones), C1BAH2 and p-XBAH2 (see sketch below), determined their crystal structures, and studied their reactions with copper(II). We envisioned that they would form macrocyclic complexes with 3-6 metal atoms. In both cases, although the initial products are soluble, as expected for the desired molecular products, we were unable to isolate well-behaved molecular solids. In the case of C1BAH2, this may be because the cyclic product requires an unusual combination of conformations of …

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A Neural Network Model For Classification Of Coastal Wetlands Vegetation Structure With Moderate Resolution Imaging Spectro-Radiometer (Modis) Data, Evaristo Joseph Liwa Jan 2006

A Neural Network Model For Classification Of Coastal Wetlands Vegetation Structure With Moderate Resolution Imaging Spectro-Radiometer (Modis) Data, Evaristo Joseph Liwa

LSU Doctoral Dissertations

Mapping coastal marshes is an important component in the management of coastal environments. Classification of marshes using remote sensing data has traditionally been performed by employing either parametric supervised classification algorithms or unsupervised classification algorithms. The implementation of these conversional classification methods is based on the underlying distributions concerning the probability density functions (PDF). Neural networks provide a practical approach to this classification because they are essentially non-parametric data transformations that are not restricted by any underlying assumptions. The major objective of this study was to evaluate the ability of neural networks using Moderate Resolution Imaging Spectro-radiometer (MODIS) data to …

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Crystal Growth And The Search For Highly Correlated Ternary Intermetallic Antimonides And Stannides, Evan Lyle Thomas Jan 2006

Crystal Growth And The Search For Highly Correlated Ternary Intermetallic Antimonides And Stannides, Evan Lyle Thomas

LSU Doctoral Dissertations

This dissertation describes the crystal growth, chemical structures, and efforts made towards the understanding of the physical properties of novel ternary rare-earth intermetallics, which may display signature behavior such as superconductivity, heavy fermion behavior, intermediate valence, and/or large magnetoresistance. To address the problem of correlating these characteristics with structural features, several ternary antimony- and tin-containing phases, Ln-T-X (Ln = lanthanide; T = Co, Ni, Pd; X = Sn, Sb), have been synthesized in single crystalline form by metallic flux-growth methods and characterized by X-ray diffraction. The antimonide compounds LnNi1-xSb2 (Ln = Y, Gd-Tb, Er, Yb), alpha, beta-LnNiSb3 (Ln = La, …

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Circuits And Structure In Matroids And Graphs, Brian Daniel Beavers Jan 2006

Circuits And Structure In Matroids And Graphs, Brian Daniel Beavers

LSU Doctoral Dissertations

This dissertation consists of several results on matroid and graph structure and is organized into three main parts. The main goal of the first part, Chapters 1-3, is to produce a unique decomposition of 3-connected matroids into more highly connected pieces. In Chapter 1, we review the definitions and main results from the previous work of Hall, Oxley, Semple, and Whittle. In Chapter 2, we introduce operations that allow us to decompose a 3-connected matroid M into a pair of 3-connected pieces by breaking the matroid apart at a 3-separation. We also generalize a result of Akkari and Oxley. In …

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Numerical Techniques For Fresnel Diffraction In Computational Holography, Richard Patrick Muffoletto Jan 2006

Numerical Techniques For Fresnel Diffraction In Computational Holography, Richard Patrick Muffoletto

LSU Doctoral Dissertations

Optical holography can produce very realistic virtual images due to its capability to properly convey the depth cues that we use to interpret three-dimensional objects. Computational holography is the use of digital representations plus computational methods to carry out the holographic operations of construction and reconstruction. The large computational requirements of holographic simulations prohibit present-day existence of real-time holographic displays comparable in size to traditional two-dimensional displays. Fourier-based approaches to calculate the Fresnel diffraction of light provide one of the most efficient algorithms for holographic computations because this permits the use of the fast Fourier transform (FFT). The limitations on …

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Ecology Of Lesser Scaup Amphipods In The Upper-Midwest: Scope And Mechanisms Of The Spring Condition Hypothesis And Implications For Migration Habitat Conservation, Michael Jason Anteau Jan 2006

Ecology Of Lesser Scaup Amphipods In The Upper-Midwest: Scope And Mechanisms Of The Spring Condition Hypothesis And Implications For Migration Habitat Conservation, Michael Jason Anteau

LSU Doctoral Dissertations

I tested the scope of the Spring Condition Hypothesis in explaining the continental population decline of lesser scaup (Aythya affinis; hereafter scaup) and explored potential mechanisms affecting female body condition to assist conservation efforts for population recovery. Lipid reserves of females currently are lower than historical values during spring migration throughout Iowa, Minnesota, and North Dakota; females catabolized lipids throughout this area (indexed by concentrations of plasma-lipid metabolites, which accounted for 75% of the variation in mass change). My results indicate that a large segment of the continental scaup population likely is affected by decreased lipid reserves, which could cause …

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School Effectiveness Research In China, Shujie Liu Jan 2006

School Effectiveness Research In China, Shujie Liu

LSU Doctoral Dissertations

The major purpose of this study was to identify the processes of effective schools in China, thereby enriching the international study of school effectiveness. A multistrand concurrent mixed model design was utilized to test the research hypotheses and answer the research questions. Both probability and purposive sampling strategies were employed in this study. The MANOVA analyses from the teacher, student, and parent questionnaires revealed a consistent result: there were significant differences between more effective and less effective schools across all the traditional school effectiveness variables. The MANOVA results for classroom teaching also demonstrated significant differences between more effective and less …

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Experimental And Computational Analysis Of Random Cylinder Packings With Applications, Wenli Zhang Jan 2006

Experimental And Computational Analysis Of Random Cylinder Packings With Applications, Wenli Zhang

LSU Doctoral Dissertations

Random cylinder packings are prevalent in chemical engineering applications and they can serve as prototype models of fibrous materials and/or other particulate materials. In this research, comprehensive studies on cylinder packings were carried out by computer simulations and by experiments. The computational studies made use of a collective rearrangement algorithm (based on a Monte Carlo technique) to generate different packing structures. 3D random packing limits were explored, and the packing structures were quantified by their positional ordering, orientational ordering, and the particle-particle contacts. Furthermore, the void space in the packings was expressed as a pore network, which retains topological and …

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High Harmonic Generation By Short Laser Pulses: Time-Frequency Behavior And Applications To Attophysics, Mitsuko Murakami Jan 2006

High Harmonic Generation By Short Laser Pulses: Time-Frequency Behavior And Applications To Attophysics, Mitsuko Murakami

LSU Doctoral Dissertations

High harmonic generation (HHG) is a process in which noble gas atoms excited by an intense laser field at frequency ω1 emit radiation of higher frequencies that are odd integer multiples of ω1. Driven by an infrared laser, high harmonic radiation can span from the optical into the extreme ultraviolet (XUV) frequency range. In this thesis, I study HHG using short laser pulses by solving the time-dependent Schrödinger equation (TDSE). In particular, I will focus on calculating and controlling the time-dependent instantaneous frequency (chirp) of high harmonics. The harmonic chirp is a direct consequence of the atom-field …

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