Digital Commons Network^™

Scalable Parallel-In-Time Integration For Equations Of Motion, Nathan W. Chapman

All Master's Theses

Physical simulations always need to balance accuracy and run-time. This work implements the Parareal Algorithm using graphics processing units across a distributed system to accurately simulate time-dependent physics while attempting to minimize runtime. Data-transfer latency is identified as the primary bottleneck, for which mitigation methods are provided. Benchmarks comparing single-GPU and distributed implementations on a spectrum of coarse and fine discretizations are analyzed.

Investigation Of Colorimetric Trends In Rare-Earth Co-Doped Ypo₄, Barit K. Essman

All Master's Theses

From detectors in scientific instrumentation to medical imaging devices and nuclear monitoring systems to LEDs seen in consumer products, phosphors are utilized in a myriad of applications experienced by both the general public and scientific community alike. For many phosphor applications, emission color and intensity are notably important features to consider. When phosphors are co-doped with rare-earth activators, the ability to predict emission intensity and color output becomes challenging due to competition kinetics and energy transfer between the dopants. During this study, correlation between trends in co-doped phosphor excitation and color output were analyzed to interpret optical behaviors originating from …

Scp 231 Dictionary + Example Problems [General Physics 1], Daniel Capic

Open Educational Resources

Student-written definitions of key physics concepts that appear in SCP 231. There are also student-written word problems with links to instructor-created video solutions.

Constructing Hamiltonians Using A Wannier Basis Set To Study Localized Electronic Interactions Using A Variational Quantum Eigensolver, Matthew D. Bruenning

Graduate Theses/Dissertations

In this study, I demonstrate how Wannier basis sets can be used to construct a tight binding Hamiltonian that is localized in real space. This Hamiltonian can then be studied using the Variational Quantum Eigensolver (VQE), which is able to extract the minimized energy of the system. Unlike Bloch functions, Wannier functions are localized in real space, allowing each Hamiltonian element to represent orbital overlaps between neighboring atomic orbitals. This locality enables a substantial reduction in the Hamiltonian’s size by including only the orbital projections that contribute meaningfully to localized interaction energies, such as those involved in adsorption. As a …

Interactions And Applications Of Optical Angular Momentum In Magneto-Optical Material, Seth R. Nelson

Dissertations, Master's Theses and Master's Reports

This dissertation explores the interactions and applications of optical angular momentum within magneto-optical materials. Beginning with a theoretical and experimental analysis of multiple reflection and refraction phenomena within magneto-optical material. We derive and verify the dependence of refractive indices on optical spin angular momentum and magneto-optical magnetization, resulting in nonreciprocal elliptical and linear polarization beam splitting effects and wavevector discretization. We fabricate a magnetless slab waveguide isolator with minimal optical loss. Extending our study to optical orbital angular momentum, we introduce a perturbation to the electronic transition model in bismuth-substituted iron garnets. We demonstrate that this perturbation leads to nonreciprocal …

0th Order Solutions Of The Wavefunctions For The Quantum Elliptical Box And Microstrip Antenna, Nishtha Tikalal

Honors Undergraduate Theses

For a quantum particle confined to a two-dimensional elliptical box or electromagnetic wave in a microstrip antenna, geometrical and boundary condition interplay result in a spectrum of spatial patterns. Due to the asymmetrical nature of the ellipse, we are faced with continuous symmetry reductions, leaving both degenerate and nondegenerate solutions. Here, we present a complete derivation of an analytical solution and visualizations of the fundamental wavefunctions for both Dirichlet and Neumann boundary conditions respectively corresponding to the quantum elliptical box and the elliptical microstrip antenna.

We demonstrate that the eigenmodes, governed by eccentricity, directly correspond to the modal field distributions …

Photocarrier Dynamics In Dielectric And Metal-Dielectric Nanocatalysts In Ambient And Operando Conditions, Sunil Gyawali

Graduate Theses, Dissertations, and Problem Reports (ETD)

Photocatalysis, a promising method for solar-to-chemical energy conversion, relies on sunlight to generate excited charge carriers in catalysts with sufficient lifetimes and mobilities to drive photoreactions. Thin-film semiconductors are essential for reducing charge recombination and enhancing mobility but suffer from a low surface-to-volume ratio problems, resulting in a reduced absorption coefficient and limiting solar-energy-conversion efficiency. Nanostructures address these limitations by enhancing light absorption and surface reactivity. However, efficient photocatalysis also requires that the semiconductor’s band edges align with the redox potential of the desired photoreaction, limiting light absorption to just some of the whole solar spectrum. In hybrid and composite …

Personalized Physics Learning Through Ai: Insights From Problem Generation, Chatbot Dialogues, And Intelligent Tutoring Systems, Atharva Dange

Physics Dissertations - Archive

Artificial intelligence (AI) is poised to transform science education, yet questions remain on how best to integrate these technologies into teaching and learning. This dissertation investigates the use of AI-driven tools in university physics courses through three complementary studies. In the first study, a generative language model (ChatGPT) was used to create novel physics homework problems aligned with course objectives. Analysis showed that, after expert vetting, AI-generated questions can foster higher-order problem-solving and reduce student reliance on solution memorization, though careful instructor oversight is required to ensure accuracy. The second study embedded an AI chatbot as a learning aid in …

Development And Application Of Gpu Based Monte Carlo Simulation Techniques In Radiation Medicine, Satzhan Sitmukhambetov

Physics Dissertations - Archive

Cancer remains a significant public health challenge, with treatments like radiation therapy forming a cornerstone of modern care. To address this challenge, advanced computer simulations can improve radiotherapy in two primary ways. From one hand, mechanistic simulations help elucidate the fundamental radiobiological working principles, which could contribute to the clinical advancements from a bottom-up framework. On the other hand, modality simulations could help design better clinical systems with better detection and therapeutic capabilities. This research enhances these critical simulation tools by introducing two significant developments.

First, this work introduces a metaphase DNA model into a microscopic Monte Carlo simulation framework …

Uncertainty In Solar Wind Propagation: An Analysis Of L1 To Earth Variability And The Implications For Geospace Modeling In Space Weather Operations, Espen T. Fredrick

Physics Dissertations - Archive

As humanity's technological dependence grows, so does its vulnerability to space weather. Space weather describes solar-driven phenomena in the near-Earth space environment and their terrestrial effects. Many of these effects occur due to the interaction of the solar wind and Earth's magnetosphere. The solar wind originates at the solar corona and carries solar plasma and magnetic field outward through the solar system. This magnetic field, known as the interplanetary magnetic field (IMF) during transit, can undergo magnetic reconnection with Earth's geomagnetic field when oppositely aligned field lines converge. This process transfers energy into Earth's magnetosphere, driving space weather phenomena.

Space …

Study Of Structural Changes In Bone From Osteogenesis Imperfecta Using Positron Annihilation Lifetime Spectroscopy, Pablo Kohlmann Garcia, Richard Vallery

Student Summer Scholars Manuscripts

Osteogenesis Imperfecta (OI), commonly referred to as Brittle Bone Disease, is a genetic disorder that results in increased bone fragility. There are many known variations, with four of them being the most common and each with a different level of severity. However, the exact causes of OI and their molecular and structural effects on bones are largely unknown. To investigate the relationship between nanoscale bone structure and disease severity, this research investigates OI by using positron annihilation lifetime spectroscopy (PALS) to understand whether normal bone structure differs from OI-infected bones. Using this method, positrons are directed towards mice’s bones, forming …

Explorations Of Dna-Single-Walled Carbon Nanotube Interactions To Develop Multiplexed Molecularly Specific Biosensors For Inflammation, Amelia K. Ryan

Dissertations and Theses

Inflammatory cytokines such as interleukin-6 (IL-6) and interleukin-12 (IL-12) are central regulators of immune signaling and key biomarkers of disease, yet existing assays for their detection remain slow, invasive, and lack multiplexing ability. This dissertation advances the development of single-walled carbon nanotube (SWCNT) optical nanosensors capable of real-time, multiplexed, and molecularly specific cytokine detection through innovative use of single-stranded DNA (ssDNA) interfaces.

First, an IL-6-specific DNA aptamer was employed as both a dispersing agent and recognition probe for SWCNT fluorescence sensing. Sequence modifications, including anchor domains, truncations, and thermally induced refolding, were systematically tested to optimize sensitivity and selectivity. The …

Metasurfaces And Their Applications In Photonic Devices, Shuwei Guo

Dissertations and Theses

Metasurfaces are flat artificial optical elements composed of dielectric and/or metallic nanostructures. They can manipulate light in unprecedented ways by altering amplitude, phase, and polarization at subwavelength scales. The ability of these two-dimensional elements to perform multiple optical functions within compact optical systems—while offering high functionality, small form factors, and easy integration into optoelectronic devices—has sparked significant interest across various fields and industries. These applications span imaging, sensing, nonlinear and quantum optics, optical computing, automotive technology, augmented and virtual reality, and more.

In this dissertation, we explore and design new multifunctional metasurfaces with a focus on manipulating spectral responses. First, …

Deep Underground Neutrino Experiment Data Caching With Frontier, Alexander Rahe

Graduate Research Theses & Dissertations

The Deep Underground Neutrino Experiment (DUNE) is an unprecedented long baseline neutrino experiment that aims to measure various neutrino mixing parameters. With state-of-the-art technology, DUNE will measure neutrino mixing angles (θ13, θ12, θ23) and a Charge-Parity (CP) violating phase (δcp) with precision and will determine the elusive mass ordering. In order to accomplish these goals, scientists all over the world must have quick and reliable access to the data provided by the DUNE detectors. The data caching system known as Frontier is a distributed database caching system that was previously used in other large particle physics experiments for this purpose. …

Optical Properties Of Rare Earth Doped Molybdenum Trioxide Thin Films, Jessica Fink

Graduate Theses/Dissertations

This study aims to investigate the optical properties of Dy-doped MoO₃ thin films. MoO₃ is a transition metal oxide that is wide band gap semiconductor. As a transition-metal oxide, it has been widely studied for its tunable properties. However, there is little literature on the subject of Dysprosium doped MoO₃, and none found as of now on thin film Dy-MoO₃ . This indicates that this topic is at best under reported, and thin film Dy-MoO₃ possesses a certain novelty. Unlike most transition metal oxides, undoped MoO₃ has a negligible crystal field splitting. This is due to the electron vacancy of …

Synthesis And Characterization Of Doped Rare-Earth Zinc Alloys, Partha Das

Graduate Theses/Dissertations

Rare-Earth-Zinc (RE-Zn) alloys doped with manganese represent a promising class of materials with diverse applications in magnetic, electronic, and thermoelectric devices. These alloys hold significant potential owing to the unique combination of rare-earth elements' properties with the versatility of zinc, augmented by manganese doping. In this study, I present the successful synthesis of ErMn_0.2Zn_11.8 alloys, achieved through self-flux method. The synthesized crystals were characterized using electron dispersive spectroscopy (EDS) and single crystal X-ray diffraction (XRD). Additionally, magnetic measurements were performed to investigate the magnetic properties. Future plans include DFT calculations and comparison study between Rare-Earth-Zinc alloys with …

Exploring Physics Teacher Identity: Pathways Toward Equitable Instruction Among Teachers, Clausell Mathis, Jomo Mutegi, Turhan Carroll, Maya Patel, Andrea Wooley

Teaching & Learning Faculty Publications

Physics teacher identity encompasses teachers' beliefs and views toward being a physics teacher. Physics teacher identity is influenced by teachers' perspectives on physics teaching and learning. Previous studies on teacher identity in general suggest that the construct is complex and malleable. Studies further suggest that it influences instructional methods, student engagement, and classroom environment. However, within physics education, there has yet to be an examination of how physics teacher identity influences "equitable" teaching approaches. This qualitative study sought to identify various dimensions of physics teacher identity and its implications for physics education research. We interviewed secondary and postsecondary physics teachers …

Eulerian Smoke Simulation With Multiple Fields, Diyang Zhang

Dartmouth College Master’s Theses

Fluid simulation is a cornerstone of computer graphics, enabling the realistic depiction of dynamic phenomena such as smoke, fire, and other gaseous behaviours. This thesis focuses on advancing Eulerian smoke simulation techniques, with a particular emphasis on grid-based simulations that capture intricate vortical structures and fine visual details.

We propose several detail-preserving frameworks that incorporate various scalar and vector fields within the simulation pipeline, including velocity, impulse, and Lamb vectors, along with their decompositions and transformed representations. By mathematically analyzing the properties of impulse, we derive its scalar fields decomposition (ImpSFD), which introduces an alternative numerical interpretation, and Vortex-Particles in …

Dosimetric Validation Of An Electron Monte Carlo (Emc) Algorithm For Small Cutouts And Extended Ssd’S: Assessing Emc In Small Field Dosimetry, Anil Basavaaraju

Theses and Dissertations

This thesis validates the accuracy and limitations of Electron Monte Carlo (eMC) simulations in Eclipse treatment planning systems for small-field electron dosimetry and extended source-to-surface distances (SSDs). Systematic measurements were performed using a microDiamond detector across various electron energies and field sizes. The study examines the discrepancies between measured and calculated (eMC) dose distributions, validating challenges due to lateral scatter disequilibrium and extended air gaps. Our findings provide systematic data for eMC dose calculations and demonstrate that eMC performs within clinical tolerances, with the ultimate goal of enhancing the precision and safety of radiation treatments.

Establishing A Conventional Linac-Based Electron Flash Beam, Justin Defrancisco

Theses and Dissertations

Problems: A rediscovered radiotherapy technique, FLASH, involves increasing the dose rate to >40 Gy/s. For a given dose, FLASH is shown to decrease the normal tissue complication probability without affecting the tumor control probability. More preclinical studies are necessary to confirm and enable these desirable properties on humans. Current preclinical investigations have diverse constraints, requiring FLASH apparatuses with flexible parameters and accurate control. However, there are limited FLASH platforms available, the existing ones are costly. Our institution is not in possession of any such infrastructure. Even if available, dosimetry and beam control in FLASH are extremely lacking. There is …

Size Dependent Thermodynamic Properties Of Dppc, Zhenghao Pan

Graduate Research Theses & Dissertations

This study explores the viability of measuring the melting transition behavior in a simple unilamellar vesicle (LUV/SUV) liposome (DPPC surfactant) system using size data from Dy- namic Light Scattering (DLS). The melting transition of phospholipid membranes has been a focal point of studies in biological systems. Conventionally, the transition temperature of a membrane system is measured using either spectroscopy or Differential Scanning Calorimetry (DSC). By assuming that the bilayer volume is conserved, it is shown that DLS provides a transition signal comparable to that of DSC and aligns with known data. The data are fit- ted using Van’t Hoff’s equation. …

Sensitivity Studies Of Vector-Like Quark (Vlq) Pair Production In The Full-Hadronic Channel At The High-Luminosity Large Hadron Collider (Hl-Lhc) And A 10 Tev Muon Collider, Olabisi Olayinka

Graduate Research Theses & Dissertations

Vector-like quarks (VLQs) appear in various extensions of the Standard Model that consider a new strongly interacting sector to resolve the fine-tuning problem. These new particles can provide radiative corrections to the Higgs mass while also having electroweak-singlet masses. This latter property would allow them to escape existing constraints from Higgs boson measurements and electroweak precision data, which disfavor the existence of a fourth generation of quarks.

VLQ can be produced at colliders, with a variety of production modes and decay mechanisms open for study. In this work, we investigate the pair production of VLQ Tops (T), which are assumed …

Effects Of A-Site Cation Structure And B-Site Metal On Optical And Electronic Properties Of 2d Ruddlesden-Popper Phase Tin-Based Hybrid Perovskites, Henry Pruett

Theses and Dissertations--Chemistry

Organic metal halide perovskites (HPs) are attractive materials for a variety of electronic applications due to their low cost, tunable band gaps, excellent charge transport properties, and high photoluminescence efficiency. As such, HPs are being investigated for use in solar cells, photodetectors, X-ray detectors, light emitting diodes, field effect transistors, lasers, resistive random-access memory, etc. Currently the most popular metal used in HPs is lead, but the use of lead comes with the potential for heavy metal exposure. Tin-based perovskites offer a less hazardous alternative, but their optoelectronic properties lag behind those of lead and less work has been done …

Optimization Of Derivation Jobs And Modernization Of I/O Integration Tests For The Atlas Epxeriment, Arthur Charles Kraus

Graduate Research Theses & Dissertations

The High-Luminosity LHC (HL-LHC) is a phase of the LHC that is expected to start toward the end of the decade. With this comes an increase in data taken per year that current software and computing infrastructure, including I/O, is being prepared to handle. The ATLAS experiment's Software Performance Optimization Team has areas in development to improve the Athena software framework that is scalable in performance and ready for wide-spread HL-LHC era data taking. One area of interest is optimization of derivation production jobs by improving derived object data stored to disk by about 4-5% by eliminating the upper-limit on …

Monte Carlo Modeling Of Spin Polarized Photoemission From Gaas At Low Temperatures And Positive Electron Affinity Surfaces, John Rison Callahan

Graduate Research Theses & Dissertations

Research and development of new photocathode materials are essential to the continuing success and productivity of accelerator technology. High-quality photocathodes characterized by high quantum efficiencies, long lifetimes, low mean transverse energies, and robustness to vacuum environments and operation loads are becoming increasingly essential to the successful operation of the next generation of high brightness accelerator applications. For nuclear and high-energy physics experiments and other applications that rely on spin-polarized electron beams, photocathodes must also demonstrate high electron spin polarizations. The development of state of-the-art spin-polarized photocathodes will require both development of methods to improve the quality of already existing cathode …

Investigation Of A Busemann Intake At Negative Angle Of Attack, Mark E. Noftz, Andrew N. Bustard, Nicholas J. Bisek, Thomas J. Juliano, Joseph S. Jewell

Publications

A high-speed, shape-transitioned, inward-turning intake was tested in Purdue’s Boeing/AFOSR Mach 6 Quiet Tunnel. The inlet model, called the Indiana Inlet (INlet), had a total contraction ratio of 4.68:1 and a design point of Mach 6 at 0° angle of attack. The model was outfitted with a suite of high-frequency pressure transducers, and the external flowfield was imaged with high-speed schlieren photography. The INlet was tested under low freestream disturbance levels for a variety of freestream unit Reynolds numbers and at-4° angle of attack. An unsteady shockwave near the leading edge of the inlet forebody, indicative of boundary layer separation, …

Atomic Physics For Everyone: An Introduction To Atomic Physics, Quantum Mechanics, And Precision Spectroscopy With No College-Level Prerequisites, Will Raven

Open Educational Resources: Textbooks

This open access textbook introduces beginning undergraduate students and high school students to the world of quantum mechanics and atomic spectroscopy. Requiring no previous knowledge of physics and no math beyond basic algebra and sines and cosines, this book focuses on concepts to make the excitement of atomic physics more accessible for learners than ever before. It comes replete with learning goals, exercises and solutions, and an optional experimental component, making this text readily adoptable for both the classroom and the undergraduate lab. The book takes the reader on a lively and engaging tour through topics at the forefront of …

Interplay Between Computational Techniques And Quantum Theory: Advancing Quantum Chaos And Quantum Error Correction, Refaat Ismail

Theses and Dissertations--Physics and Astronomy

This dissertation investigates computational techniques addressing critical problems arising within quantum chaos and quantum error correction (QEC). First, we investigate quantum dynamics via the Lanczos algorithm, establishing how its computational features — branching patterns, convergence, and complexity saturation — relate to physical properties like spectral statistics and operator matrix elements. We derive a formula connecting Lanczos coefficients to spectral densities for two-branched Lanczos sequences, revealing how branching patterns encode level repulsion—a hallmark of quantum chaos. Furthermore, we develop an analytic framework predicting Krylov complexity saturation from static system properties alone. Specifically, we decompose the saturation value into a spectral density-dependent …

Laser–Assisted Free–Free (Laff) Electron Scattering: An Elastic Angular Distribution In Argon And The Use Of A Novel Pulsed-Laser Multipass System In Laff Experiments, Charles M. Weaver

Theses and Dissertations--Physics and Astronomy

Laser–assisted free–free experiments investigate the emission or absorption of photons when an electron scatters from an atom in the presence of a laser field.

We measured the relative differential cross sections for 350 eV electrons scattered by an argon target in the presence of 1.17 eV photons from a Nd:YAG laser. The angular distribution for elastically scattered 350 eV electrons was measured over scattering angles from 4◦ to 80◦. This distribution exhibits a pronounced maximum near 47◦ and is symmetric about this angle, as predicted by a Kroll–Watson approximation (KWA) calculation for the experimental kinematics. These measurements directly test a …

Simulations Of Electron Detection Systematic Errors For A Ucna+ Experiment, Rashika Gupta

Theses and Dissertations--Physics and Astronomy

The Ultracold Neutron Asymmetry+ (UCNA+) experiment at the Los Alamos Neu- tron Science Center (LANSCE) Ultracold Neutron source is an upgrade of the UCNA experiment, designed to measure the neutron beta decay asymmetry parameter, A 0 , with a precision of less than 0.2% using polarized ultracold neutrons (UCN). Neutron beta decay is governed by the weak interaction, and a precise measurement of A 0 provides a determination of the axial-vector to vector coupling ratio, λ = gA /gV . When combined with a measurement of the neutron lifetime, this allows the extraction of the Cabibbo-Kobayashi-Maskawa (CKM) matrix element Vud …