Technological Challenges Of 1-Dimensional Magnetic Photonic Crystals,
2010
Edith Cowan University
Technological Challenges Of 1-Dimensional Magnetic Photonic Crystals, Mikhail Vasiliev, Kamal Alameh, Dmitry E. Balabanov, Vladimir I. Burkov, V. V. Koledov, Viacheslav A. Kotov, V. G. Shavrov, Anotoly K. Zvezdin
Research outputs pre 2011
Visible-region magnetic photonic crystals (MPC) designed for higher-order bandgap operation have been proposed to overcome the technological restrictions originating from the strong thickness dependency of the individual magnetic layer properties observed in MPC structures.
Optical Control Of Ultrafast Spin -Wave Relaxation By Magnetic Anisotropy In A Ferromagnet,
2010
College of William & Mary - Arts & Sciences
Optical Control Of Ultrafast Spin -Wave Relaxation By Magnetic Anisotropy In A Ferromagnet, Kevin James Smith
Dissertations, Theses, and Masters Projects
This thesis presents an investigation of the damping of spin waves in ferromagnetic Au(3 nm)/Ni(10 nm)/MgO(001) thin films using the time-resolved Magneto-optical Kerr Effect (TR-MOKE) and ferromagnetic resonance (FMR) techniques. In the optical measurements, a 150 fs, 800 nm laser beam pulse is split into pump and probe components. The pump pulse, containing most of the beam energy, thermally excites coherent spin precession. The weaker probe pulse, time-delayed by a variable beam path, captures the magnetization dynamics via the polar MOKE effect, and oscillations are observed as a function of external field amplitude and direction. The extracted precession frequency is …
Fast-Response Liquid Crystal Displays,
2010
University of Central Florida
Fast-Response Liquid Crystal Displays, Meizi Jiao
Electronic Theses and Dissertations
After about five decades of extensive material research and device development, followed by massive investment in manufacturing technology, thin-film-transistor liquid-crystaldisplay (TFT-LCD) has finally become the dominant flat panel display technology. Nowadays, LCD performances, such as viewing angle, contrast ratio, and resolution, have reached acceptable levels. The remaining major technical challenges are response time, light efficiency, and sunlight readability. Fast response time is desired to reduce motion blur and to enable field sequential color displays using red (R), green (G), and blue (B) LEDs (light emitting diodes) without noticeable color breakup. Sequential RGB colors would eliminate the commonly used spatial color …
Nonlinear Absorption And Free Carrier Recombination In Direct Gap Semiconductors,
2010
University of Central Florida
Nonlinear Absorption And Free Carrier Recombination In Direct Gap Semiconductors, Peter D. Olszak
Electronic Theses and Dissertations
Nonlinear absorption of Indium Antimonide (InSb) has been studied for many years, yet due to the complexity of absorption mechanisms and experimental difficulties in the infrared, this is still a subject of research. Although measurements have been made in the past, a consistent model that worked for both picosecond and nanosecond pulse widths had not been demonstrated. In this project, temperature dependent two-photon (2PA) and free carrier absorption (FCA) spectra of InSb are measured using femtosecond, picosecond, and nanosecond IR sources. The 2PA spectrum is measured at room temperature with femtosecond pulses, and the temperature dependence of 2PA and FCA …
Freeform Reflector Design With Extended Sources,
2010
University of Central Florida
Freeform Reflector Design With Extended Sources, Florian Fournier
Electronic Theses and Dissertations
Reflector design stemmed from the need to shape the light emitted by candles or lamps. Over 2,000 years ago people realized that a mirror shaped as a parabola can concentrate light, and thus significantly boosts its intensity, to the point where objects can be set afire. Nowadays many applications require an accurate control of light, such as automotive headlights, streetlights, projection displays, and medical illuminators. In all cases light emitted from a light source can be shaped into a desired target distribution with a reflective surface. Design methods for systems with rotational and translational symmetry were devised in the 1930s. …
Near-Field Radiative Transfer: Thermal Radiation, Thermophotovoltaic Power Generation And Optical Characterization,
2010
University of Kentucky
Near-Field Radiative Transfer: Thermal Radiation, Thermophotovoltaic Power Generation And Optical Characterization, Mathieu Francoeur
University of Kentucky Doctoral Dissertations
This dissertation focuses on near-field radiative transfer, which can be defined as the discipline concerned with energy transfer via electromagnetic waves at sub-wavelength distances. Three specific subjects related to this discipline are investigated, namely nearfield thermal radiation, nanoscale-gap thermophotovoltaic (nano-TPV) power generation and optical characterization. An algorithm for the solution of near-field thermal radiation problems in one-dimensional layered media is developed, and several tests are performed showing the accuracy, consistency and versatility of the procedure. The possibility of tuning near-field radiative heat transfer via thin films supporting surface phononpolaritons (SPhPs) in the infrared is afterwards investigated via the computation of …
New Laser Technologies Analysis Of Quantum Dot And Lithographic Laser Diodes,
2010
University of Central Florida
New Laser Technologies Analysis Of Quantum Dot And Lithographic Laser Diodes, Abdullah Demir
Electronic Theses and Dissertations
The first part of this dissertation presents a comprehensive study of quantum dot (QD) lasers threshold characteristics. The threshold temperature dependence of a QD laser diode is studied in different limits of p-doping, hole level spacing and inhomogeneous broadening. Theoretical analysis shows that the threshold current of a QD laser in the limit of uniform QDs is not temperature independent and actually more temperature sensitive than the quantum well laser. The results also explain the experimental trends of negative characteristic temperature observed in QD lasers and clarify how the carrier distribution mechanisms inside and among the QDs affect the threshold …
Silicon-Sensitized Erbium Excitation In Silicon-Rich Silica For Integrated Photonics,
2010
University of Central Florida
Silicon-Sensitized Erbium Excitation In Silicon-Rich Silica For Integrated Photonics, Oleksandr Savchyn
Electronic Theses and Dissertations
It is widely accepted that the continued increase of processor performance requires at least partial replacement of electronic interconnects with their photonic counterparts. The implementation of optical interconnects requires the realization of a silicon-based light source, which is challenging task due to the low emission efficiency of silicon. One of the main approaches to address this challenge is the use of doping of silicon based matrices with optical centers, including erbium ions. Erbium ions incorporated in various hosts assume the trivalent state (Er3+) and demonstrate a transition at 1.54 μm, coinciding with optical transmission windows in both silicon and silica. …
Development Of Optical Coherence Tomography For Tissue Diagnostics,
2010
University of Central Florida
Development Of Optical Coherence Tomography For Tissue Diagnostics, Panomsak Meemon
Electronic Theses and Dissertations
Microvasculature can be found in almost every part of the human body, including the internal organs. Importantly, abnormal changes in microvasculature are usually related to pathological development of the tissue cells. Monitoring of changes in blood flow properties in microvasculature, therefore, provides useful diagnostic information about pathological conditions in biological tissues as exemplified in glaucoma, diabetes, age related macular degeneration, port wine stains, burn-depth, and potentially skin cancer. However, the capillary network is typically only one cell in wall thickness with 5 to 10 microns in diameter and located in the dermis region of skin. Therefore, a non-invasive flow imaging …
Modeling And Design Of A Photonic Crystal Chip Hosting A Quantum Network Made Of Single Spins In Quantum Dots That Interact Via Single Photons,
2010
University of Central Florida
Modeling And Design Of A Photonic Crystal Chip Hosting A Quantum Network Made Of Single Spins In Quantum Dots That Interact Via Single Photons, Hubert P. Seigneur
Electronic Theses and Dissertations
In this dissertation, the prospect of a quantum technology based on a photonic crystal chip hosting a quantum network made of quantum dot spins interacting via single photons is investigated. The mathematical procedure to deal with the Liouville-Von Neumann equation, which describes the time-evolution of the density matrix, was derived for an arbitrary system, giving general equations. Using this theoretical groundwork, a numerical model was then developed to study the spatiotemporal dynamics of entanglement between various qubits produced in a controlled way over the entire quantum network. As a result, an efficient quantum interface was engineered allowing for storage qubits …
The Development Of Scalable Pump Techniques For Gg Iag Fiber Lasers And Passive Athermalization Techniques For Solid State Laser,
2010
University of Central Florida
The Development Of Scalable Pump Techniques For Gg Iag Fiber Lasers And Passive Athermalization Techniques For Solid State Laser, William Hageman
Electronic Theses and Dissertations
This dissertation consists of two parts: research pertaining to the development of scalable pump techniques for gain guided index-antiguided fiber lasers and research relating to the development of passive athermalization schemes for solid state lasers. The first section primarily details the development of a side pump scheme that allows for power scaling of gain-guided index anti-guided fibers. While these fibers have been demonstrated in past research, none have used a pump technology capable of pumping with the efficiencies, uniformity, and necessary length to allow for scaling of the fiber lasers to high output powers. The side pumped scheme developed in …
Near-Field Optical Interactions And Applications,
2010
University of Central Florida
Near-Field Optical Interactions And Applications, David Haefner
Electronic Theses and Dissertations
The propagation symmetry of electromagnetic fields is affected by encounters with material systems. The effects of such interactions, for example, modifications of intensity, phase, polarization, angular spectrum, frequency, etc. can be used to obtain information about the material system. However, the propagation of electromagnetic waves imposes a fundamental limit to the length scales over which the material properties can be observed. In the realm of near-field optics, this limitation is overcome only through a secondary interaction that couples the high-spatial-frequency (but non-propagating) field components to propagating waves that can be detected. The available information depends intrinsically on this secondary interaction, …
Micro-Electro-Mechanical Systems (Mems) And Agile Lensing-Based Modules For Communications, Sensing And Signal Processing.,
2010
University of Central Florida
Micro-Electro-Mechanical Systems (Mems) And Agile Lensing-Based Modules For Communications, Sensing And Signal Processing., Syed Reza
Electronic Theses and Dissertations
This dissertation proposes the use of the emerging Micro-Electro-Mechanical Systems (MEMS) and agile lensing optical device technologies to design novel and powerful signal conditioning and sensing modules for advanced applications in optical communications, physical parameter sensing and RF/optical signal processing. For example, these new module designs have experimentally demonstrated exceptional features such as stable loss broadband operations and high > 60 dB optical dynamic range signal filtering capabilities. The first part of the dissertation describes the design and demonstration of digital MEMS-based signal processing modules for communication systems and sensor networks using the TI DLP (Digital Light Processing) technology. Examples of …
The Effect Of Curvature Rate On The Received Power In Parabolic Reflector,
2009
Western Michigan University
The Effect Of Curvature Rate On The Received Power In Parabolic Reflector, Amean Al_Safi
Amean S Al_Safi
In this paper we study the effect of curvature rate on the generated electric field at the focus point if the frequency and diameter are constants .We assume that the incident electromagnetic waves distributed uniformly on each point of the reflector surface ;hence we can imagine that this reflector has uniform surface charge ,and this body will generate an electric field on all points in front of it (including the focus point) . This field can be obtained by using coulomb’s law .The derived expression for electric field show that X and Y components will vanish and the electric field …
