Electromagnetics and Photonics Commons^™

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 …

Long Cavity Quantum Dot Laser Diode And Monolithic Passively Mode-Locked Operation, K Shavitranuruk

Electronic Theses and Dissertations

Advantage of the single QD active layer is its potential for very low threshold current density, which in turn can produce low internal optical loss. The low threshold current density and low internal loss thus enable a significant increase in laser diode cavity length. Because of the importance of the threshold current density in heatsinking, future technology of broad-area monolithic laser diodes can be implemented. The dissertation describes the development and the unique characteristics of single QD active layer laser with long cavity. The data are presented on single layer QD laser diodes that reach threshold current densities values of …

Fabrication Of Integrated Optofluidic Circuits In Chalcogenide Glass Using Femtosecond Laser Direct Writing, Troy P. Anderson

Electronic Theses and Dissertations

Femtosecond laser direct writing (FLDW) is a versatile process that uses focused femtosecond pulses to modify the physical structure of a material, which can result in a shift of optical properties such as the linear and nonlinear refractive index. If the photon energy of the femtosecond pulses lies below the material bandgap, nonlinear absorption rather than linear absorption becomes the dominant mechanism of energy transfer to the material. In this manner, a focused femtosecond pulse train can be used to fabricate functional features such as optical waveguides, diffractive optical elements, or micro-fluidic elements within the volume of a transparent medium. …

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 …

Electroless Deposition Of Superconducting Magnesium Diboride Thin Films On Various Substrates, Khrupa Saagar Vijayaragavan

Wayne State University Theses

ABSTRACT

ELECTROLESS DEPOSITION OF SUPERCONDUCTING MAGNESIUM DIBORIDE THIN FILMS ON VARIOUS SUBSTRATES

by

KHRUPA SAAGAR VIJAYARAGAVAN

MAY 2010

Advisor: Dr. Susil K Putatunda

Dr. Gavin Lawes

Major: Chemical Engineering

Degree: Masters of Science

Superconducting thin films of magnesium diboride were synthesized by a novel electroless plating process. Electroless plating shares many similarities to electroplating with the major difference being the absence of a continuous bias voltage. Significantly, this work represents the first investigation where electroless deposition has been used to prepare compounds, as opposed to the elemental metals considered in all previous studies. Magnesium Diboride is a recently discovered superconducting …

Plasmon Enhanced Near-Field Interactions In Surface Coupled Nanoparticle Arrays For Integrated Nanophotonic Devices, Amitabh Ghoshal

Electronic Theses and Dissertations

The current thrust towards developing silicon compatible integrated nanophotonic devices is driven by need to overcome critical challenges in electronic circuit technology related to information bandwidth and thermal management. Surface plasmon nanophotonics represents a hybrid technology at the interface of optics and electronics that could address several of the existing challenges. Surface plasmons are electronic charge density waves that can occur at a metal-dielectric interface at optical and infrared frequencies. Numerous plasmon based integrated optical devices such as waveguides, splitters, resonators and multimode interference devices have been developed, however no standard integrated device for coupling light into nanoscale optical circuits …

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 …

Application Of Antenna Synthesis And Digital Signal Processing Techniques For Active Millimeter-Wave Imaging Systems, Wilson Ariel Caba

Electronic Theses and Dissertations

Millimeter-wave imaging has gathered attention in recent years for its ability to penetrate clothing, thin layers of soils, and certain construction materials. However, image quality remains a challenge that needs to be addressed. One way of improving image quality is by increasing the dimensions of the collecting aperture. A sparse array can be used to synthesize a larger aperture with a limited set of relatively small detectors. In this research we design, build, and test a test-bed having an active source at 94 GHz and an array of coherent detectors, mounted on arms that extend radially on a rotary table. …

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 …

Design And Simulation Of Silica-On-Silicon Pump/Signal Multiplexer For Hybrid Passive-Active Optical Devices., Alvin Law Wen Pin

Student Works (2010-2019)

This dissertation describes the design and simulation of silica-on-silicon pump/signal multiplexer for hybrid passive-active optical devices. Uniform symmetric directional couplers and planar Bragg gratings were utilized in this work, forming the essential building blocks in a waveguide amplifier. Several designs in relation to the multiplexers are presented in this work, with the simplest application for the directional coupler as a pump/signal multiplexer. A 980/1550 nm and an 800/1310 nm pump/signal multiplexers for erbium doped and bismuth doped waveguide amplifier, respectively were modeled. These couplers were designed and simulated in Rsoft BeamPROP environment, utilizing 3D Finite Difference Beam Propagation Method (FD-BPM) …

Nonlinear Fiber Lasers Using Bismuth Based Erbium Doper Fiber Amplifier., Sharifeh Shahi

Student Works (2010-2019)

A thorough study on Bismuth-based Erbium-doped fiber (Bi-EDF) is presented for wide-band amplifiers and multi-wavelength fiber laser applications. This fiber allows high Erbium ions concentration to be doped without a significant concentration quenching effect. The high refractive index characteristic in the Bi-EDF has broadened the emission spectrum of Erbium ions to achieve a broader gain spectrum up to extended L-band region compared to normal silica-based Erbium-doped fiber (EDF). The Bi-EDFA performances have been investigated in terms of power conversion efficiency (PCE), quantum conversion efficiency (QCE), gain and noise figure. The highest QCE and PCE for a 215 cm long of …

Reflective And Beam-Through Types Of Fiber Optic Sensor For Displacement Measurement., Walaa Fawzi Al–Masri

Student Works (2010-2019)

This dissertation proposes and demonstrates fiber-optic displacement sensor (FODS) theoretically and experimentally using the intensity modulation technique to measure a displacement from a probe and target. The sensor uses a multimode plastic bundled fiber as a probe and He-Ne laser as a source. The performance of the sensor is compared for different type of probe and target. For a pair type bundled fiber, both the experimental and theoretical results exhibit the same type of characteristic features. The front slope sensitivities are obtained at 1.71 and 1.0 mW/μm for the theoretical and experimental approaches respectively, while the back slope sensitivities are …

Harvesting Single Ferroelectric Domain Stressed Nanoparticles For Optical And Ferroic Applications, Gary Cook, J. L. Barnes, S. A. Basun, Dean R. Evans, Ron F. Ziolo, Arturo Ponce, Victor Yu. Reshetnyak, Anatoliy Glushchenko, Partha P. Banerjee

Electrical and Computer Engineering Faculty Publications

We describe techniques to selectively harvest single ferroelectric domain nanoparticles of BaTiO3 as small as 9 nm from a plethora of nanoparticles produced by mechanical grinding. High resolution transmission electron microscopy imaging shows the unidomain atomic structure of the nanoparticles and reveals compressive and tensile surface strains which are attributed to the preservation of ferroelectric behavior in these particles.

We demonstrate the positive benefits of using harvested nanoparticles in disparate liquid crystal systems.

Characterization Of Atmospheric Turbulence Effects Over 149 Km Propagation Path Using Multi-Wavelength Laser Beacons, Mikhail Vorontsov, Gary W. Carhart, Venkata S. Rao Gudimetla, Thomas Weyrauch, Eric Stevenson, Svetlana Lachinova, Leonid A. Beresnev, Jony Jiang Liu, Karl Rehder, Jim F. Riker

Electrical and Computer Engineering Faculty Publications

We describe preliminary results of a set of laser beam propagation experiments performed over a long (149 km) near-horizontal propagation path between Mauna Loa (Hawaii Island) and Haleakala (Island of Maui) mountains in February 2010. The distinctive feature of the experimental campaign referred to here as the Coherent Multi-Beam Atmospheric Transceiver (COMBAT) experiments is that the measurements of the atmospheric-turbulence induced laser beam intensity scintillations at the receiver telescope aperture were obtained simultaneously using three laser sources (laser beacons) with different wavelengths (λ1 = 0.53 μm, λ2 = 1.06 μm, and λ3 = 1.55 μm). The presented experimental results on …

Inductively Coupled Plasma Dry Etching Process On Planar Lightwave Circuit Fabrication., Chuah Khoon Seah

Student Works (2010-2019)

The main objective of this project is to master state-of-the-art techniques and knowledge in silica etching in order to achieve high quality waveguide circuit on Planar Lightwave Circuit devices. Another objective is to optimize the clean room research strength, surface characterization, microscopy techniques and similar semiconductor manufacturing processes.Initially, these processes were conducted with wet etching method that utilized diluted hydrofluoric acid (HF) and buffered oxide etch (BOE). Several problems arising such as mask peel-off, poor sidewall profile and defect waveguide channel during the pattern transfer process due to its’ isotropic nature. Alternatively, dry etching method was conducted via Inductively Coupled …

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 …

12 Bit Charge Redistribution Digital To Analog Converter For The Residence Time Fluxgate Magnetometer, Miguel Angel Alamillo

Open Access Theses & Dissertations

The continuous advances in CMOS VLSI technology have culminated in high speed, low voltage CMOS digital circuits with gate delays below 50 ps at 1.5 V supply. At the same time, high voltage analog signal processing has fallen behind to the high flexibility and high reliability of DSP. However, the main drawback of DSP is the need for high accuracy low distortion data converters and as a consequence of the persistent efforts of reducing size, cost and power of solid-state components the field of CMOS Mixed-Signal circuit design has become of the utmost importance.

The obvious functionality of data converters …

Optimization Of Inductively Coupled Plasma Dry Etching For Planar Waveguide Fabrication., Lim Weng Hong

Student Works (2010-2019)

Optimization of the Inductively Coupled Plasma (ICP) dry etching process parameters has been carried out. Seven main etching characteristics were considered in order to produce good etching quality. These characteristics are glass etching rates, selectivity of chromium to glass etching rate, channel side wall roughness, channel side wall vertical profile, channel cleanliness, critical dimension and resolution. Several ICP parameters that are affecting the etching characteristic were optimized in this work. These optimised ICP parameters obtained from this work are ICP power (880 W), bias power (45 W), operating chamber pressure (10 mtorr), reactant gas composition, reactant gas flow rate (35sccm …

Characterization Of An Inductively Coupled Plasma Produced In Argon At 13.56 Mhz., Lim Ai Nuan

Student Works (2010-2019)

The electrical and plasma characteristics of radio frequency (13.56 MHz) inductively coupled argon plasma (RF ICP) were studied in this project. On the electrical breakdown properties, the breakdown voltage has a general appearance of Paschen’s curve and the minimum is achieved at 0.1 mbar. After ignition, two modes of discharge exist, namely, the E mode at low RF power and H mode at high RF power. Mode transition that occurs is accompanied by abrupt changes in both electrical and plasma characteristics. Hysteresis is observed in the mode transitions and has a minimum at 0.1 mbar. The resistance reflected into the …

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 …