Zinc tin oxide (ZTO) films deposited by pulsed laser deposition (PLD) are
investigated as a channel layers for transparent thin-film transistors (TTFTs).
Films are deposited on glass for characterization, and transistor channel layers are
deposited onto aluminum oxide-titanium oxide/tin doped indium oxide/glass
substrates (ATO/ITO/glass) to produce TTFTs.
UV-visible spectroscopy on...
Lipids, especially phospholipids, are very common
but important molecules found in cells and animal
tissue, performing many biological functions, particularly
in membranes. Lipids, when mixed with water,
spontaneously form ordered systems, such as micelles,
vesicles and multibilayers. The size of these systems
and their degree of ordering depend on the...
A spectral fitting routine was developed to analyze X-ray emissions in neutron capture decay
processes that produce ¹⁹⁷Hg and ¹⁹⁷Pt. Through correcting for X-ray emissions, the
77.3 keV γ gamma ray intensities were analyzed. The thermal cross sections for the production of
¹⁹⁷Hg and ¹⁹⁷Pt were found to be 2088...
String theory, one of the more popular approaches to quantizing gravity, is a highly complex
theory, involving high level mathematics and physics. But the basic ideas of string theory are not inaccessible, even to the undergraduate. This document acts as report to my thesis project, the writing of A Detailed...
This project calculates the value of β for ice particles based on wavelength dependent values of their refractive and absorptive indices. β is the ratio of the force due to radiation to the force due to gravity acting on a particle in the solar system. This parameter can later be...
The electrical properties of amorphous and crystalline titanium dioxide polymorphs are reported. Titanium dioxide is a widely used transparent semiconductor and it is a useful oxide model. Using variable temperature transport measurements of thin films, it was possible to establish the activation energy barrier for conduction. This was accomplished using...
Brownian motion is the movement of a particle in a fluid resulting from collisions with surrounding molecules. It has modern applications in simulating fluid dynamics and the motion of proteins in biophysics. Brownian motion simulations generally evolve the initial state by applying Newton’s second law to every particle. These simulations...
Soon the largest fusion project in the world, ITER, will attempt to produce more fusion power than required to sustain the fusion reaction, this is known as ignition. The tokamak (a toroidal fusion device) being built in France will be running at such high temperatures that heat distribution is a...
When a nucleus is in an excited state, it will decay to lower energy by emitting photons. Often there are several intermediate stages in a decay cascade. Occasionally the photons in a cascade will be emitted in coincidence. This will be resolved by the detector not as two distinct photons,...
High resolution images of a dim companion in a binary star system can be obtained using a Digital Micromirror Array (DMA) as an optical mask. Imaging can be problematic because the intense light from the main star can saturate the detector and leave the companion unnoticed. Placement of the DMA...
We exhibit long-lived resonances in scattering from two-dimensional soft cage potentials comprised of three and four Gaussian peaks. Specific low-energy resonances with very narrow width are shown to correspond to classical multiple-reflection events. These states have much larger probability densities inside the cage than outside and mimic bound states in...
Multivariable functions permeate physics, mathematics, and other sciences. Understanding how quantities in multivariable relationships change together – or co-vary – is important for studying physical systems. In this project, we asked junior-level physics majors to describe the covariation of quantities in a multivariable context given a 2D graph. We identified...
The ring disclination is a topological defect that may be suitable for light polarization inside of a nematic liquid crystal. Due to its stability and chirality, the ring disclination could also allow for theoretical applications to quantum and classical field theories as a model for fundamental particles. In order to...
An experiment has been conducted using a triple directional
correlation method developed by K. S. Krane, R. M. Steffen and R.
M. Wheeler (ref. 3). This method is presented and two normal detection geometries are introduced. The performance of the N1- and N2-
geometry was studied in four experiments using...
In 1877 John Kerr described an experiment that demonstrated a quadratic change in refractive index in a plate glass placed in a strong external electric field. This results in a nonlinear relationship between the average electric polarization within the materials and the intensity of the applied electric field. This opened...
Bulk properties of CuSc₁₋ₓMgₓO₂, CuSc₁₋ₓMgₓO₂₊y, BaCu₂S₂, Bai₁₋ₓKCu₂S₂, BaCu₂Se₂
and Bai₁₋ₓKₓCu₂Se₂ are investigated supporting the search for highly conductive p-type
thin films. Mg is an efficient dopant in CuScO₂ with conductivity up to l.5.10⁻² S/cm.
Oxidation of CuScO₂:Mg leads to further increase in conductivity up to 0.5 S/cm. The
amount of...
Herein, a program of research is detailed related to transport through the Si metal oxide semiconductor (MOS) quantum dots fabricated in a process flow compatible with modern ULSI (ultra large scale integrated circuit). Silicon quantum dots were fabricated by placing split gates within a MOSFET structure. Quantum dots of several...
A knowledge of the time rates for intermediate reactions
during the photolysis of nitrogen dioxide enables one to deduce the
possible intermediate reactions which are responsible. An experiment has been devised and constructed which will measure the time
rates for photochemical reactions occurring in ranges of one micro
second to...
Exciton-polaritons are a form of light-matter coupling that have potential applications as photonic transistors and logic gates. In order for a photonic transistor or logic gate to be integrated with room temperature fiber-optic technology, excitons-polaritons need to be stable at room temperature and compatible with the red and near-infrared wavelengths...
A thermal beam of lithium atoms excited to high Rydberg states
by pulsed electron impact has been studied by time-of-flight analysis.
Near the end of a 35-cm field-free flight path, the excited atoms pass
through a pair of electric field plates before entering an excited-atom
detector. Electric field ionization was...
Liquid surfaces are very abundant in nature. Despite the importance of the liquid
interface in general, experimental molecular-level data was almost completely lacking
prior to the last decade and a half. The intent of this work is to provide a means by
which experimental data on the composition of liquid...
Semiconductors serve an integral role in our technologies today. However, with new advancements in ultra-fast electronics, we are approaching the fundamental speed limits of traditional silicon-based semiconductors. Silicon-based semiconductors typically exhibit photocarrier dynamics in nanosecond timescales. Transition metal dichalcogenides (TMDs) are 2D materials shown to exhibit photocarrier dynamics in picosecond...
We consider development of sand ripples in shallow water flows which do not reach an equilibrium height but have a time-varying ripple height that slowly reaches a maximum value and then is quickly destroyed by the fluid. A simple scenario to explain the time periodic behavior of the sand ripples...
Rectial Program
| Scherzo - Oleg Miroshnikov
| Syrinx - Claude Debussy
| Bachianas Brasileiras No. 6 - Heitor Villa-Lobos (Feat. Kaleigh Hull on flute)
| Turkisher March - Christian Julius Weissenborn (Feat. Annie Kosanovic-Brown, Andrew McKelvey on bassoon)
| Pizzicati Polka - Leo Delibes (DeArr. Mark Eubanks) (Feat. Annie...
Pulsed laser deposition was used to create 0.1-Bi(Zn₀.₅ Ti₀.₅)O₃-0.9-BaTiO₃ (BZT-BT) thin films to examine the effects of laser energy (2.25 or 2.5 J/cm²) , pulse frequency (2 Hz or 5 Hz), and deposition temperature (550, 600, 650, and 700°C) on the electrical properties of the films. These effects were analyzed...
By alloying face centered cubic CaSe with orthorhombic SnSe, we created the heterostructural alloy
Sn1-xCaxSe. The phase separated lms created with a high deposition temperature acted as highly crys-
talline SnSe while the low deposition temperature lms acted as a mix of SnSe and CaSe. For the alloyed
lms we...
The Van der Pauw method for transport measurements of conductivity and carrier concentration were tested on indium-tin-oxide (ITO) films and silicon wafers, and then implemented on Cu10xAgxZn2Sb4S13 thin films. ITO was used as a test case for high temperature transport measurements because it a well characterized semi-metal. The mobility of...
Thermal transport properties of a material are often difficult to measure, especially for
thin films, but they are important for materials that have applications in modern devices,
such as nano-scale electronics, thermoelectrics, and thermally resistive coatings. In this
thesis, we describe an apparatus developed to measure the thermal conductivity of...
Amorphous multicomponent metals have promising applications in novel electronic devices because of their atomically smooth surface morphology and lack of grain boundaries. It is important to understand the thermal transport properties of amorphous metals and an accurate measurement of their thermal conductivity will be essential for further improvement of device...
This dissertation reports on the computational physics research in the area of
inhomogeneous fluids. I first discuss the theory background for this work beginning
with water, which is important for the two published articles that are presented in
this work (Chapters 5 and 6). Next, I give a brief overview...
A new experimental technique for the study of
atom-surface interactions is obtained by passing an atomic
beam containing high-Rydberg states through a fine mesh
target. The technique is demonstrated to be a sensitive
probe of the electric fields of adsorbed dipole layers in
transmission experiments in which a time-dependent beam...
Effective two-body interactions were obtained from
realistic nucleon-nucleon potentials and applications made
in calculations of ground state properties of even-even N=Z light nuclei. The admixture of high momentum states into
the nuclear wavefunction caused by the strong, short-range
repulsion of the two-nucleon force was taken into account
by making a...
Computational statistical mechanics leans heavily on the class of Markov Chain Monte Carlo Algorithms. Many such algorithms exist, and simulations can run for several weeks, making the selection of algorithms a difficult, but critical task. In this work, we introduce a benchmark system of two quadratic wells with an analytical...
The three-grating optical interferometer is studied to identify restrictions
on alignment and improve stability. A description of the way a three-grating
interferometer works is given as well as a method for proper set up. The overall
power loss through the three gratings is measured and can be used to estimate...
The N=88 isotones lie on the onset of nuclear deformation and have a complicated nuclear structure. To better understand this region, the nuclear levels of ¹⁵⁰Sm were studied in three different β decay experiments. De-populating γ-rays were measured using the 8π spectrometer, an array of 20 Compton suppressed Ge detectors....
Detailed analyses of snow crystal sequence and atmospheric
conditions were accomplished utilizing macrophotographic techniques
for obtaining the snow crystal record at Santiam Pass in the Oregon
Cascades on 19-20 January, 14-15 February, and 9-10 March, 1967.
The photographic equipment consisted of a 35 millimeter single lens
reflex camera, bellows, and...
The three-body heterogeneous and wall recombination coefficients for atomic oxygen were measured using an electron paramagnetic
resonance spectrometer to monitor the time dependence of the
atomic oxygen concentration. This measurement was made for a
pressure range of from .224 to 1.10 torr using pyrolysis of ozone as
a source of...
Perturbed Angular Correlations (PAC) spectroscopy is an effective
local probe technique often employed in the characterization of defects or
phase transitions in any of a variety of materials. This technique relies
upon the ability of probe nuclei to function as gauges of the magnetic
fields and electric field gradients local...
The behavior of all of the observed molecular band
emission as well as the prominent atomic line emission
from a pulsed microwave helium plasma is given. Extensive
efforts to purify the helium include the use of a
uranium getter, a quartz diffusion tube, and a cataphoretic
discharge. The plasma is...
This investigation is a study of how the magnitude
and energy distribution of the photoelectric current from
the light emergent side of thin silver films varies with
film thickness. The Fowler-Dubridge graphical analysis
of the energy distribution of photoelectrons is used to
determine the energy of the most energetic of...
Loop quantum gravity is a framework for quantizing general relativity which imposes a discrete structure on space. In exploring the structure of loop quantum gravity, researchers have investigated loop quantum cosmology, a toy model with reduced degrees of freedom while maintaining a discrete space. Polymer quantum mechanics is a framework...
The optical response of metallic structures is dominated by the dynamics of their free electron plasma. Plasmonics, the area of optics specializing in the electromagnetic behavior of heterogeneous structures with metallic inclusions, is undergoing rapid development, fueled in part by recent progress in experimental fabrication techniques and novel
theoretical approaches....
Gallium arsenide shows excellent promise for terahertz generation using mid infrared.
This is for two reasons. First, the indices of refraction for the terahertz (nTHz=3.61 at 1 THz) and mid infrared (nopt=3.431 at 2 μm) are close allowing a long interaction length.
Second, the linear absorption is low at terahertz...
In this project we measure the neutron capture cross section of ²⁰⁸Pb. We began by calibrating our silicon detector with ²⁰⁴Tl. Two experiments were then performed, the first in December of 1999 and the second in March of 2000. Both experiments were performed in the nuclear reactor of the Radiation...
An evaluation of the meteorological usefulness of a maser RF
amplifier on an AN/MPS-34 X-band weather radar indicates that there
are both advantages and disadvantages to its use. The problems
associated with the maser used in this study included tuning problems,
loss of gain through loss of liquid helium and...
We present an analysis of the relationship between spectral lag and luminosity in time-resolved segments of long gamma-ray bursts detected by BATSE, an experiment aboard the Compton Gamma Ray Observatory satellite. For full bursts, there is a well-established correlation between the lag, which is easily computed, and the total burst...
We explore the interactions between charge transfer exciton states (CTEs) and an optical microcavity by testing the effects that cavity resonance has on the CTEs and if CTEs can be coupled with a photon to create quasiparticles known as polaritons. Exciton polaritonics is becoming a booming area of research mainly...
The aim of this Physics Education Research project was to implement a modified version
of Calibrated Peer Review and measure the impacts in junior-level students' scientific
writing. The project developed and implemented a set of guiding questions, instructor
written examples, and a rubric which were implemented in a multi-staged process,...
Organic aggregates and transparent amorphous metals are transforming opto-electronic devices such as highly efficiency solar cells and flexible displays. We present a fundamental optical study of how local morphology critically impacts the device performance of both stacked, conjugated organics and In-Ga-Zn-O (IGZO) transparent metallic materials. Derivatives of anthradithiophene (ADT): ADTTES-F,...
In chapter 3 of our paper we present equations of motion for continuous mass
distribution subject to hydrodynamic forces in their most general form. We start
with equations for discrete mass particles and then transform the equations so
that it is appropriate for a continuous mass distribution. As we do...
The formation of carbonaceous and silicate precursor molecules to astrophysical dust grains is investigated. Using density functional theory (DFT) in combination with global optimization techniques, the ground-state binding energies of dust precursors are determined. These results are employed in atomistic nucleation theory (ANT) to predict the critical size and nucleation...
Fiber Bragg gratings have become an important element in the fields of telecommunications and fiber optical sensing. Their small size, light weight and high tunability have made them ideal for many unique applications. In this paper the fabrication of these devices is investigated.
Following a review of current literature and...
Knowledge concerning trade wind cumulus, one of the most dominant cloud types
on the planet, has become increasingly important when considering global issues such as climate change due to their potential influence on the Earth’s energy budget. In this project, using data from the Rain in Cumulus over the Ocean...
Shocked porous granular material experiences pressure dependent compaction. D. John
Pastine introduced a model in which the degree of compaction is dependent on the pressure induced
by the shock wave, the shear strength of the material, and the distribution of void sizes. In the
past, the model could only be...
The effect of ultra-high pressure on the thermal emf of a
chromelialumel thermocouple is investigated using an indirect
method which does not require a direct knowledge of the temperature
of the pressurized junction. The unknown temperature is written
parametrically as a function of a directly measured quantity, the
electrical power...
The LIGO interferometers have reached their designed sensitivity level which is greater than any other interferometer ever built. At this point, it is important to have a proper understanding of small perturbations that might still exist (until now these issues did not come to the forefront because other more critical...
Nuclear techniques such as perturbed angular correlation (PAC) sample the hyperfine interactions of a large number of probe atoms in specific crystallographic sites. Real crystals contain static defects producing a distribution of electric field gradients (EFGs) that add to the ideal EFG of the crystal at any given probe site....
The decay of Pd¹⁰⁹, Pd¹¹¹ [superscript g], and Pd¹¹¹ [superscript m] produced by thermal neutron irradiation of palladium targets has been investigated. Gamma ray energies and relative intensities have been measured with a high resolution Ge(Li) spectrometer. From energy sums and relative intensity considerations level schemes for Ag ¹⁰⁹ and...
The decay of ⁶¹Cu and ⁵⁹Cu produced by (d, n) reactions on
natural nickel has been investigated. Gamma-ray energies and relative
intensities were measured with a high resolution Ge(Li) spectrometer.
The gamma-gamma coincidence spectrum of ⁶¹Cu was
studied with a Ge(Li)-NaI(T1) system. From these data decay
schemes of ⁶¹Cu and...