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Simulating Strongly Coupled Many-Body Systems With Quantum Algorithms, Manqoba Qedindaba Hlatshwayo

Dissertations

The complexity of the nuclear many-body problem is a severe obstacle to finding a general and accurate numerical approach needed to simulate medium-mass and heavy nuclei. Even with the advent of exascale classical computing, the impediment of exponential growth of the Hilbert space renders the problem intractable for most classical calculations. In the last few years, quantum algorithms have become an attractive alternative for practitioners because quantum computers are more efficient in simulating quantum physics than classical computers. While a fully fault-tolerant universal quantum computer will not be realized soon, this dissertation explores quantum algorithms for simulating nuclear physics suitable …

Insights Into The Structural And Electronic Properties Of 2d Polar Sic/Gec Heterostructures And Asxp1−X Alloys., Kazi Jannatul Tasnim

Electronic Theses and Dissertations

Due to the unique structural and electronic properties along with the practical applications in current and near future, investigations about the group-IV graphene-like two-dimensional (2D) sheets have been accelerated. Among them, 2D SiC and GeC sheets are polar materials with in-plane charge transfer from Si (Ge) to C atoms. An interesting question is how the electrostatic force, triggered by such in-plane charge transfer, plays a role in stabilizing the vertical heterostructures formed by 2D SiC and GeC sheets beyond vdW interaction. To answer this question, we have systematically investigated, in my PhD research projects, the effects of the electrostatic interaction …

Modelling Galaxy Cluster Triaxiality In Stacked Cluster Weak Lensing Analyses, Hao-Yi Wu

Physics Faculty Publications and Presentations

Counts of galaxy clusters offer a high-precision probe of cosmology, but control of systematic errors will determine the accuracy of this measurement. Using Buzzard simulations, we quantify one such systematic, the triaxiality distribution of clusters identified with the redMaPPer optical cluster finding algorithm, which was used in the Dark Energy Survey Year-1 (DES Y1) cluster cosmology analysis. We test whether redMaPPer selection biases the clusters’ shape and orientation and find that it only biases orientation, preferentially selecting clusters with their major axes oriented along the line of sight. Modelling the richness–mass relation as log-linear, we find that the log-richness amplitude …

Self-Calibrating Optical Galaxy Cluster Selection Bias Using Cluster, Galaxy, And Shear Cross-Correlations, Chenxiao Zeng, Andrés N. Salcedo, Hao-Yi Wu, Christopher M. Hirata

Physics Faculty Publications and Presentations

The clustering signals of galaxy clusters are powerful tools for self-calibrating the mass–observable relation and are complementary to cluster abundance and lensing. In this work, we explore the possibility of combining three correlation functions – cluster lensing, the cluster–galaxy cross-correlation function, and the galaxy autocorrelation function – to self-calibrate optical cluster selection bias, the boosted clustering and lensing signals in a richness-selected sample mainly caused by projection effects. We develop mock catalogues of redMaGiC-like galaxies and redMaPPer-like clusters by applying halo occupation distribution models to N-body simulations and using counts-in-cylinders around massive haloes as a richness proxy. In addition …

Spectroscopy Of Highly Charged Ions For Astrophysical And Laboratory Plasma Diagnostics, Yang Yang

All Dissertations

Electron beam ion traps (EBITs) are small-scale laboratory devices that create and trap highly charged ions (HCI) for spectroscopic studies. These devices create plasma conditions resembling astrophysical environments like stellar winds and supernova remnants, providing valuable insights into astrophysical plasma. Theoretical models for such systems require incorporating relativistic and quantum electrodynamics effects, making experimental studies of HCIs essential for benchmarking these theories.

Spectral analysis of astrophysical and laboratory plasma requires understanding the ionization balance. Accurate atomic data, including excitation, ionization, and recombination cross sections, along with precise knowledge of operating conditions such as electron beam density, electron beam energy, and …

Lepton Flavor Violation And Lepton Flavor Universality Violation: Opportunity For New Physics Beyond The Standard Model, Fang Xu

Arts & Sciences Graduate Student Theses and Dissertations

The Standard Model (SM) of Particle Physics has been remarkably successful in explaining the fundamental forces and classifying elementary particles. However, there are various experimental and theoretical indications that suggest the need to go beyond the SM (BSM) and expand our understanding of the fundamental nature of the universe. From a theoretical perspective, there are several limitations of the SM that suggest the existence of a more fundamental theory. For example, the SM does not incorporate gravity, and it fails to explain the hierarchy problem. Additionally, the nature of dark matter and the origin of the mass hierarchy of elementary …

Pursuit Of Ultimate Tomographic Image Quality: From Classical Methods To Deep Learning, Shiwei Zhou

Physics Dissertations - Archive

Medical imaging plays a crucial role in modern healthcare, serving as a vital component in the realms of diagnosis and treatment. It encompasses a broad spectrum of techniques and technologies aimed at visualizing the internal structure, physiology and bio-chemical processes inside the human body. Medical imaging has revolutionized medical practice by enabling doctors to diagnose diseases and monitor treatments without resorting to invasive procedures. Computed Tomography (CT) is an important tool of medical imaging. A CT scan employs computer-processed combinations of multiple X-ray images taken from different angles to generate cross-sectional images, providing significantly more detailed structural information compared to …

Relation Between Solitary Wave Occurrence And Solar Wind Parameters During The Kelvin-Helmholtz Instability, Tyler Workman

Physics Theses - Archive

The Kelvin-Helmholtz instability (KHI) is an important mechanism whereby the solar wind transports energy and momentum into the magnetosphere. One unresolved topic is the role of kinetic phenomena and turbulence in mediating this energy transport. Previous studies hypothesized that the prevalence of electrostatic solitary waves, an artifact of kinetic turbulence, decreased along the flanks as the instability grew. These previous studies had been conducted using 3 KHI events. For this study, we test the hypothesis and further investigate how these solitary waves affect the local plasma with an expanded list of 15 KHI events. A combination of solar wind data …

Core-Collapse Supernovae And Their Remnants: Chandra Study Of Sn 1987a And A Multi-Wavelength Follow-Up Of Sn 2021krf, Aravind Pazhayath Ravi

Physics Dissertations - Archive

Understanding how exploding stars impact their surroundings is of fundamental importance to all areas of astrophysics. Young supernovae (SNe) and their remnants open a window into directly studying the composition and distribution of the fresh products of nucleosynthesis. They also are instrumental in probing the ambient circumstellar medium (CSM), revealing the late-stage evolution of massive stars that culminates in a cataclysmic explosion. My thesis is divided into understanding the evolution of two core-collapse SNe: SN 1987A and SN 2021krf. Supernova (SN) 1987A is the closest observed SN (about 51 kpc) in the last 400 years and offers a unique opportunity …

Quantum Electrodynamic Corrections To Cyclotron States In A Penning Trap, Ulrich D. Jentschura, Christopher Moore

Physics Faculty Research & Creative Works

We analyze the leading and higher-order quantum electrodynamic corrections to the energy levels for a single electron bound in a Penning trap, including the Bethe logarithm correction due to virtual excitations of the reference quantum cyclotron state. The effective coupling parameter αc in the Penning trap is identified as the square root of the ratio of the cyclotron frequency, converted to an energy via multiplication by the Planck constant, to the electron rest mass energy. We find a large, state-independent, logarithmic one-loop self-energy correction of order α α_c⁴mc²ln(α_c^-2), where m is the …

Study Of Highly Charged Ion Charge Exchange With Applications To X-Ray Astrophysics, Richard Mattish

All Dissertations

Highly charged ions (HCIs) exist in many hot astrophysical environments where they play an important role in plasma dynamics. Charge exchange involving highly charged ions has been shown to be responsible for many observed X-ray emissions from a variety of astrophysical sources. Proper modeling of these environments requires an understanding of this process, including the electronic structure of each ion species as well as their charge exchange cross sections. This dissertation investigates charge exchange processes with highly charged ions which are present in astrophysical environments via a laboratory-based study.

The Clemson University electron beam ion trap (CUEBIT) laboratory was utilized …

High-Power Laser Cooling And Temperature-Dependent Fluorescence Studies Of Ytterbium Doped Silica, Brian Topper

Optical Science and Engineering ETDs

Experimental observation of optical refrigeration using ytterbium doped silica glass in recent years has created a new solution for heat mitigation in high-power laser systems, nonlinear fiber experiments, integrated photonics, and precision metrology. Current efforts of different groups focus on compositional optimization, fiber fabrication, and investigating how much silica can be cooled with a laser. At the start of this work, the best effort in laser cooling ytterbium doped silica saw cooling by 6 K from room temperature. This dissertation follows the experimental efforts that culminated in the increase of this initial record by one order of magnitude. Comprehensive spectroscopic …

A Novel Technique To Solve Fractional Differential Equations Using Fractional-Order B-Polynomial Basis Set, Md Habibur Rahman

Theses and Dissertations

This thesis uses B-Polynomial bases to solve both one-dimensional and multi-dimensional linear and nonlinear partial differential equations and linear and nonlinear fractional differential equations. The approach involves constructing an operational matrix from the terms of these equations using Caputo's fractional derivative of fractional B-polynomials. This leads to a semi-analytical solution derived from a matrix equation, and the results obtained using this method are compared to analytical and numerical solutions presented by other authors. The method is shown to be effective in calculating approximate solutions for various differential equations and provides a higher accuracy level than finite difference methods. This technique …

Study Of Microphonic Effects On The C100 Cryomodule For High Energy Electron Beam Accelerators, Caleb James Hull

Mechanical & Aerospace Engineering Theses & Dissertations

The Continuous Electron Beam Accelerator Facility (CEBAF) at Thomas Jefferson National Laboratory (JLab) is a particle accelerator which can accelerate an electron beam to relativistic speeds and apply the beam onto target samples. The C100 superconducting radio frequency (SRF) cavity is the primary accelerating structure of the C100 cryomodule, one of the many cryomodules which compose the CEBAF linear accelerator. SRF cavities are particularly sensitive to internal and external vibrations that can result in a phenomenon called microphonics which degrade the operational stability of a cryomodule.

The purpose of this thesis is to investigate the significance of mechanical disturbances on …

Portable Optical Spectroscopic Assay For Non-Destructive Measurement Of Key Metabolic Parameters On In Vitro Cancer Cells And Organotypic Fresh Tumor Slices, Jing Yan, Carlos Frederico Lima Goncalves, Madison O. Korfhage, Zahid Hasan, Teresa Whei-Mei Fan, Xiaoqin Wang, Caigang Zhu

Markey Cancer Center Faculty Publications

To enable non-destructive metabolic characterizations on in vitro cancer cells and organotypic tumor models for therapeutic studies in an easy-to-access way, we report a highly portable optical spectroscopic assay for simultaneous measurement of glucose uptake and mitochondrial function on various cancer models with high sensitivity. Well-established breast cancer cell lines (MCF-7 and MDA-MB-231) were used to validate the optical spectroscopic assay for metabolic characterizations, while fresh tumor samples harvested from both animals and human cancer patients were used to test the feasibility of our optical metabolic assay for non-destructive measurement of key metabolic parameters on organotypic tumor slices. Our optical …

Azimuthal Correlations Within Exclusive Dijets With Large Momentum Transfer In Photon-Lead Collisions, A. Tumasyan

Department of Physics and Astronomy: Faculty Publications

The structure of nucleons is multidimensional and depends on the transverse momenta, spatial geometry, and polarization of the constituent partons. Such a structure can be studied using high-energy photons produced in ultraperipheral heavy-ion collisions. The first measurement of the azimuthal angular correlations of exclusively produced events with two jets in photon-lead interactions at large momentum transfer is presented, a process that is considered to be sensitive to the underlying nuclear gluon polarization. This study uses a data sample of ultraperipheral lead-lead collisions at √s_NN = 5.02 TeV, corresponding to an integrated luminosity of 0.38 nb⁻¹, collected with …

Uncertainty In The Physical Basis Of Estimates Of Relative Biological Effectiveness In Carbon Radiotherapy, Shannon Hartzell, Shannon Hartzell Ph.D.

Dissertations and Theses (Open Access)

Carbon ion radiotherapy is a novel modality used for the treatment of tumors that are unresectable, close to critical structures, or resistant to standard radiotherapy. A unique benefit of this therapy is the relative biological effectiveness (RBE) of the beam (i.e., how biologically potent carbon ions are as compared to x-rays), which is significantly elevated. This RBE also varies as a function of many parameters, and there are currently several models implemented in clinical and research-based treatment planning systems with which to predict RBE. These algorithms are computationally expensive and there are currently no means of validating their implementation within …

Entangled Photon Anti-Correlations Are Evident From Classical Electromagnetism, Ken Wharton, Emily Adlam

Mathematics, Physics, and Computer Science Faculty Articles and Research

For any experiment with two entangled photons, some joint measurement outcomes can have zero probability for a precise choice of basis. These perfect anti-correlations would seem to be a purely quantum phenomenon. It is, therefore, surprising that these very anti-correlations are also evident when the input to the same experiment is analyzed via classical electromagnetic theory. Demonstrating this quantum–classical connection for arbitrary two-photon states and analyzing why it is successful motivates alternative perspectives concerning entanglement, the path integral, and other topics in quantum foundations.

Density Functional Theory Study Of Dopant Incorporation Into Gamma-Uo3, Nicholas James Wilson

Open Access Theses & Dissertations

Uranium trioxide (UO3) is a stable uranium oxide found throughout the nuclear fuel cycle. The γ-UO3 phase is of particular interest as the most stable at ambient conditions. As such, the γ-UO3 structure was selected for a theoretical investigation into the incorporation of metal dopants for nuclear intentional forensics applications. The two lattice types of this phase, tetragonal (I41/amd) and orthorhombic (Fddd), were investigated and found to be energetically identical, and as such the smaller tetragonal structure was selected for doping. Three transition metal dopants (Cr, Fe, and Ni) were incorporated into the structure interstitially and substitutionally at a total …

A Dft Analysis And Simple Hamiltonian Modeling Of A Molecular System Employed For Experimental Evidence Of Quantum Teleportation, Pedro Ulises Medina Gonzalez

Open Access Theses & Dissertations

Radical ion pairs (RIPs) have been used to demonstrate quantum teleportation in molecular systems for applications in quantum information science. Covalent organic donor-acceptor (D-A) molecules can produce RIPs through photo-induced charge transfer and an additional radical (R) molecule makes quantum teleportation possible. We present the electronic structure and analyze charge transfer excited states of a recently studied [1] D-A-R molecular system using density functional theory. The distances between donor-acceptor and donor-radical are about 12.9 \AA $\,$ and 21.9 \AA, respectively. The excitation energies are calculated using the perturbative delta-SCF method and agree with other conventional excited-state methods and experimental reference …

Signatures Of Black Holes, Alexandra B. Chanson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In this defense I will describes three approaches to learn more about the relationship between the dynamics of black-holes and the distinctive signatures of a black hole systems: infinitesimal changes in the black hole background producing field excitations relating new fundamental black hole thermodynamic relations, mechanisms powering relativistic black hole jets and spontaneous symmetry breaking in five space-time dimensions, and physical signatures of black hole event horizons as conformal field theory duals (in both d=4,5 dimensional axisymmetric spacetimes).

The Derivation Of Sodium Density In The Mesosphere And Lower Thermosphere From The Na Lidar Photon Counting Profiles, Xiaoqi Xi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Derivation of Sodium (Na) number density from the Na lidar observations requires the in situ temperature and wind information because the absorption cross-section of the Na atom is a function of these dynamic parameters. The Na number density above ~ 110 km altitude was difficult to derive with the conventional algorithm, however. The standard output of the Na number density that utilizes the lidar-measured wind and temperature information falls short at ~ 110 km altitude and above due to the relatively large measurement uncertainties in the two critical parameters (low signal-to-noise ratio). Therefore, an innovative algorithm that may drive the …

The Time-Dependent Ionospheric Model Using A Tec-Driven Servo: An Investigation Of The Capabilities And Limitations, Jenny Rebecca Whiteley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The ionosphere is a region of the atmosphere with a high density of electrons. These electrons affect the behavior of any electromagnetic wave that passes through the ionosphere. Communication and geolocation systems, such as traditional radio and Global Positioning Systems, depend on emitted electromagnetic signals being picked up by a receiver. The presence of the ionosphere affects the behavior of the signal and the quality of the service. Hence, the interactions between electromagnetic waves and the ionosphere provide a major motivation to understand, research, and successfully model and predict the ionosphere and its physical phenomena. This study focused on determining …

Nonlinear Charge And Spin Currents In Non-Centrosymmetric Electron Systems, Aniruddha Pan

All Dissertations

In this thesis, we discuss the existence of spin and charge currents in systems with broken spin inversion symmetry proportional to the magnitude square of the driving electric and thermal fields. This outcome is predicated on symmetry considerations in the momentum space, whereby the product between the current operator and the out-of-equilibrium distribution function has to be even.

First, we derive the second-order correction to the particle distribution function $\delta f^{(2)}$ in a semi-classical approximation, considering the local change in the equilibrium distribution function caused by external fields. Our approach departs significantly from the previous theory where $\delta f^{(2)}$ is …

Deep Virtual Pion Pair Production, Dilini Lakshani Bulumulla

Physics Theses & Dissertations

This experiment investigates the deep virtual production of both σ− and ρ− mesons, with a particular focus on the microscopic structure of the σ mesons. While the ρ meson is an ordinary qq¯ pair, the σ meson is composed of not only the typical qq¯ pair, making it a topic of controversy for nearly six decades. Although the existence of the σ− meson is now well established, its microscopic structure remains poorly understood. The primary objective of this thesis is to contribute to the understanding of the σ meson by analyzing its deep virtual production. The main focus of this …

Spectral Broadening Effects On Pulsed-Source Digital Holography, Steven A. Owens, Mark F. Spencer, Glen P. Perram

Faculty Publications

Using a pulsed configuration, a digital-holographic system is setup in the off-axis image plane recording geometry, and spectral broadening via pseudo-random bit sequence is used to degrade the temporal coherence of the master-oscillator laser. The associated effects on the signal-to-noise ratio are then measured in terms of the ambiguity and coherence efficiencies. It is found that the ambiguity efficiency, which is a function of signal-reference pulse overlap, is not affected by the effects of spectral broadening. The coherence efficiency, on the other hand, is affected. As a result, the coherence efficiency, which is a function of effective fringe visibility, is …

Fem Simulations Of Plasmon Field Enhancement In Gold Nanoparticle Dimers And Gold Nanoparticle-Nanorod Dimers, Edward J. Lipchus

Graduate Masters Theses

Plasmon resonance refers to the collective oscillation of free electrons in a nanomaterial in response to an incident electromagnetic field. When two plasmonic nanoparticles are placed close together, their localized surface plasmon resonances can couple and interact. The resulting plasmonic coupling leads to the formation of new plasmonic modes in the dimer system, significantly enhancing the electromagnetic fields in the vicinity of the nanoparticles, with various interesting and potentially useful applications. This thesis investigates the optical field enhancement arising from gold nanoparticle dimers in an aqueous dielectric medium, using the Finite Element Method simulation software COMSOL Multiphysics. The simulations provide …

Computational And Experimental Study On Undoped And Er-Doped Lithium Tantalate Nanofluorescent Probes, Mkhitar A. Hobosyan, Andrea Pelayo Carvajal, Bhupendra B. Srivastava, Tamanna Zakia, Mohammed Uddin, Karen S. Martirosyan, Eric Rodriguez, Kofi Nketia Ackaah-Gyasi, Nicholas Dimakis

Physics & Astronomy Faculty Publications

We present a combined density functional theory (DFT) and experimental work on lithium tantalate LiTaO3 (LT) and its Er-doped counterparts. We calculate the electronic and optical properties for both LT and LT:Er+3, with Er occupying either Li or Ta sites, at 4.167 mol%. The generalized gradient approximation (GGA) calculations show that the Er-4 f bands appear closer to the conduction band bottom and to the valance band top, for the first and second doped configurations, respectively. This agrees with changes in the imaginary part of the frequency dependent dielectric function between the doped configurations. There are striking differences between the …

Search For Higgs Boson Pair Production In The Multiple Lepton Final State Using Proton-Proton Collision Data At √S =13 Tev From The Atlas Detector, Santosh Parajuli

Physics Theses and Dissertations

In this thesis, a search is presented for the production of Higgs boson pairs in final states containing three light leptons (e/mu). The analysis utilizes data collected by the ATLAS detector at the Large Hadron Collider from proton-proton (pp) collisions at a center-of-mass energy of √s=13 TeV, corresponding to an integrated luminosity of 140 fb-1. The investigation aims to identify any significant deviations from the expected background levels defined by the Standard Model. The Higgs boson, as the cornerstone of the electroweak symmetry breaking mechanism, plays a crucial role in our understanding of particle physics. Studying the production of Higgs …

Conservation Laws And The Foundations Of Quantum Mechanics, Yakir Aharonov, Sandu Popescu, Daniel Rohrlich

Mathematics, Physics, and Computer Science Faculty Articles and Research

In a recent paper, [Y. Aharonov, S. Popescu, D. Rohrlich, Proc. Natl. Acad. Sci. U.S.A.118 e1921529118 (2021)], it was argued that while the standard definition of conservation laws in quantum mechanics, which is of a statistical character, is perfectly valid, it misses essential features of nature and it can and must be revisited to address the issue of conservation/nonconservation in individual cases. Specifically, in the above paper, an experiment was presented in which it can be proven that in some individual cases, energy is not conserved, despite being conserved statistically. It was felt however that this is worrisome and …