Digital Commons Network^™

Can The Xy+Z Heisenberg Model Be Compressed Using The Yang-Baxter Equation? An Exploration Of The Compression Of Quantum Time Dynamic Circuits Describing Heisenberg Spin Chains, Miriam Caron, Bo Peng Dr., Scott Gould Dr., Kevin Setter Dr., Niranjan Govind Dr.

Pitzer Senior Theses

Quantum computing is currently deployed on noisy intermediate-scale quantum (NISQ) devices, which are only able to simulate circuits reliably on shallow depth quantum circuits. A promising problem on near-term quantum computers is quantum time dynamics (QTD). However, QTD circuits grow with increasing time simulations making them difficult to simulate on NISQ devices. This thesis project explores QTD simulations in variations of 1D Heisenberg spin chains with nearest-neighbor and transverse external field interactions with an eye towards studying the dynamics in broader classes of spin models. I first study the quantum Yang-Baxter equation (YBE) and how it has been shown to …

Beam Dynamics Simulations And Systematic Studies For The Muon G-2 Experiment At Fermilab, Abel M. Lorente Campos

Theses and Dissertations--Physics and Astronomy

The first results of the positive muon anomalous magnetic moment from the Muon g-2 Experiment at Fermilab differs from the Standard Model prediction by 3.3 standard deviations, with an experimental uncertainty of 0.46 ppm. Combining this result with the previous measurement from the Brookhaven National Laboratory, it sets the difference between experiment and theory at 4.2 standard deviations. The goal of the Muon g-2 Experiment at Fermilab is to increase this discrepancy to 5 standard deviations, which would require unprecedented precision in the measurements of 0.14 ppm. Of significant importance to achieving this precision, beam and spin dynamics simulations are …

Nonequilibrium Dynamics Of Correlated Disordered Systems Under Interaction Quenches, Eric A. Dohner

Legacy Theses & Dissertations (2009 - 2024)

Correlated, disordered lattice fermion systems out of equilibrium have been understudied, at least in part for lack of tools to study them. The development of a new method, the NE-DMFT+CPA, is explicated, for investigating the properties of these systems. This method combines DMFT and the CPA using the Kadanoff-Baym-Keldysh contour-time formalism to study the dynamics of interacting disordered systems out of equilibrium. The method is detailed, then applied to the case of the Anderson-Hubbard model: first to replicate well-known equilibrium results, then to study the case of the model under the effect of an interaction quench. Here the effect of …

Surface Reconstruction In Iron Garnets, Sushree Dash

Dissertations, Master's Theses and Master's Reports

This dissertation presents the results of a study investigating the physical mechanisms underlying an unexpectedly large increase in magneto-optic efficiency observed in iron garnet. Such materials are technologically important for telecommunications due to their nonreciprocal optical action. In the past, our group had found evidence of an enhanced Faraday rotation in bismuth-substituted iron garnet films less than 50 nm thick. Subsequent investigation revealed that this enhancement could be traced to surface effects. This is significant because understanding these phenomena could be used to formulate engineering solutions for device miniaturization. In this dissertation, we present the result of a research project …

Analysis Of Biologically Effective Dose For Retroactive Yttrium-90 Trans-Arterial Radioembolization Treatment Optimization, Mj Lindsey

CMC Senior Theses

Trans-arterial radioembolization (TARE) is a protracted modality of radiation therapy where radionuclides labeled with Yttrium-90 (⁹⁰Y) are inserted inside a patient's hepatic artery to treat hepatocellular carcinoma (HCC). While TARE has been shown to be a clinically effective and safe treatment, there is little understanding of the radiobiological relationship between absorbed dose and tissue response, and thus there is no dosimetric standard for treatment planning. The Biologically Effective Dose (BED) formalism, derived from the Linear-Quadratic model of radiobiology, is used to weigh the absorbed dose by the time pattern of delivery. BED is a virtual dose that can …

Effect Of Decorating Super Paramagnetic Iron Oxide Nanoparticles With Silver Nanoparticles On Their Magneto-Photo Thermal Heating Efficiency, Anthony Joseph Afful

All Graduate Theses, Dissertations, and Other Capstone Projects

Cancer treatment is rather dangerous to the body, often involving many secondary effects, including nausea, hair loss, and weight fluctuations. The search for non-invasive, highly efficient, and targetable treatments ameliorates these issues. Super paramagnetic iron oxide nanoparticles (SPIONS) have been used for other medical purposes such as magnetic resonance imaging contrast agent and is being extensively studied as a potential candidate for many cancer therapeutic and diagnostic approaches due to its biocompatibility and superior magnetic properties. When subjected to an external alternating magnetic field SPIONS generate heat mainly due to the friction of the SPIONS against the fluid it is …

Determining Deuterium Polarization Via Nuclear Magnetic Resonance, Nicholas Muche

Honors Theses and Capstones

Dynamic Nuclear Polarization (DNP) is a method by which the spins of electrons are specifically targeted by microwaves at resonance frequency in order to induce spin flips. Occasionally, the electron spins couple with nuclear spins and nuclear spin flips are induced. The relaxation time of the electron is significantly lower than that of the nuclei, which allows for large polarization. The main goal of the Slifer Lab is to utilize specifically prepared crystalline structures in order to separate the convoluted energy transitions ("Batman Peak") in the deuterium's nuclear magnetic resonance (NMR) signal, which would allow for tensor enhancement of deuterium. …

Patch-Wise Training With Convolutional Neural Networks To Synthetically Upscale Cfd Simulations, John P. Romano, Alec C. Brodeur, Oktay Baysal

Mechanical & Aerospace Engineering Faculty Publications

This paper expands the authors’ prior work[1], which focuses on developing a convolutional neural network (CNN) model capable of mapping time-averaged, unsteady Reynold’s-averaged Navier-Stokes (URANS) simulations to higher resolution results informed by time-averaged detached eddy simulations (DES). The authors present improvements over the prior CNN autoencoder model that result from hyperparameter optimization, increased data set augmentation through the adoption of a patch-wise training approach, and the predictions of primitive variables rather than vorticity magnitude. The training of the CNN model developed in this study uses the same URANS and DES simulations of a transonic flow around several NACA 4-digit airfoils …

A Jwst/Nirspec Exploration Of The Connection Between Ionization Parameter, Electron Density, And Star-Formation-Rate Surface Density In Z = 2.7–6.3 Galaxies, Naveen Reddy, Michael W. Topping, Ryan L. Sanders, Alice E. Shapley, Gabriel B. Brammer

Physics and Astronomy Faculty Publications

We examine the factors responsible for the variation in the ionization parameter (U) of high-redshift star-forming galaxies based on medium-resolution JWST/NIRSpec observations obtained by the Cosmic Evolution Early Release Science survey. The sample consists of 48 galaxies with redshifts zspec = 2.7−6.3, which are largely representative of typical galaxies at these redshifts. The [S II] λλ6718, 6733 doublet is used to estimate electron densities (n e), and dust-corrected Hα luminosities are used to compute ionizing photon rates (Q). Using composite spectra of galaxies in bins of [O III] λλ4960, 5008/[O II] λλ3727, 3730 (O32) as a proxy for U, we …

The Dust-To-Gas Mass Ratio Of Luminous Galaxies As A Function Of Their Metallicity At Cosmic Noon, Gergö Popping, Irene Shivaei, Ryan L. Sanders, Tucker Jones, Alexandra Pope, Naveen Reddy, Alice E. Shapley, Alison L. Coil, Mariska Kriek

Physics and Astronomy Faculty Publications

Aims. We aim to quantify the relation between the dust-to-gas mass ratio (DTG) and gas-phase metallicity of z = 2.1-2.5 luminous galaxies and contrast this high-redshift relation against analogous constraints at z = 0.

Methods. We present a sample of ten star-forming main-sequence galaxies in the redshift range 2.1 < z < 2.5 with rest-optical emission-line information available from the MOSDEF survey and with ALMA 1.2 millimetre and CO J = 3-2 follow-up observations. The galaxies have stellar masses ranging from 1010.3 to 1010.6 M? and cover a range in star-formation rate from 35 to 145 M? yr-1. We calculated the gas-phase oxygen abundance of these galaxies from rest-optical nebular emission lines (8.4 < 12+log (O=H) < 8.8, corresponding to 0.5..1.25 Z?). We estimated the dust and H2 masses of the galaxies (using a metallicity-dependent CO-to-H2 conversion factor) from the 1.2mm and CO J = 3..2 observations, respectively, from which we estimated a DTG.

Results. We find that the galaxies in this sample follow the trends already observed between CO line luminosity and dust-continuum luminosity from z = 0 to z = 3, extending such trends to fainter galaxies at 2.1 < z < 2.5 than observed to date. We find no second-order metallicity dependence in the CO - dust-continuum luminosity relation for the galaxies presented in this work. The DTGs of main-sequence galaxies at 2.1 < z < 2.5 are consistent with an increase in the DTG with gas-phase metallicity. The metallicity dependence of the DTG is driven by the metallicity dependence of the CO-to-H2 conversion factor. Galaxies at z = 2.1-2.5 are furthermore consistent with the DTG-metallicity relation found at z = 0 (i.e. with no significant evolution), providing relevant constraints for galaxy formation models. These results furthermore imply that the metallicity of galaxies should be taken into account when estimating cold-gas masses from dust-continuum emission, which is especially relevant when studying metal-poor low-mass or high-redshift galaxies.

Measurements Of Dielectron Production In Au + Au Collisions At √Snn = 27, 39, And 62.4 Gev From The Star Experiment, Star Collaboration

Physics and Astronomy Faculty Publications

We report systematic measurements of dielectron (e+e−) invariant-mass Mee spectra at midrapidity in Au + Au collisions at √s NN = 27, 39, and 62.4 GeV taken with the STAR detector at the Relativistic Heavy Ion Collider. For all energies studied, a significant excess yield of dielectrons is observed in the low-mass region (0.40 < M ee < 0.75 MeV/c2 ) compared to hadronic cocktail simulations at freeze-out. Models that include an in-medium broadening of the ρ-meson spectral function consistently describe the observed excess. In addition, we report acceptance-corrected dielectron-excess spectra for Au + Au collisions at midrapidity (|yee| < 1) in the 0–80% centrality bin for each collision energy. The integrated excess yields for 0.4 < Mee < 0.75 GeV/c2 , normalized by the charged particle multiplicity at midrapidity, are compared with previously published measurements for Au + Au at √s NN = 19.6 and 200 GeV. Models that include an in-medium broadening of the ρ-meson spectral function consistently describe the observed excess. The normalized excess yields in the low-mass region show no significant collision energy dependence. The data, however, are consistent with model calculations that demonstrate a modest energy dependence.

Measurements Of The Elliptic And Triangular Azimuthal Anisotropies In Central 3he + Au, D + Au And P + Au Collisions At √Snn P = 200 Gev, Star Collaboration

Physics and Astronomy Faculty Publications

The elliptic (v2) and triangular (v3) azimuthal anisotropy coefficients in central He3+Au, d+Au, and p+Au collisions at sNN=200 GeV are measured as a function of transverse momentum (pT) at midrapidity (|η|< 0.9), via the azimuthal angular correlation between two particles both at |η|< 0.9. While the v2(pT) values depend on the colliding systems, the v3(pT) values are system independent within the uncertainties, suggesting an influence on eccentricity from subnucleonic fluctuations in these small-sized systems. These results also provide stringent constraints for the hydrodynamic modeling of these systems.

Observation Of Directed Flow Of Hypernuclei 3/Λ H And 4/Λ H In √𝑠nn=3  Gev Au+Au Collisions At Rhic, Star Collaboration

Physics and Astronomy Faculty Publications

We report here the first observation of directed flow (v1) of the hypernuclei H/Λ 3 and H/Λ 4 in mid-central Au+Au collisions at √sNN=3 GeV at RHIC. These data are taken as part of the beam energy scan program carried out by the STAR experiment. From 165×106 events in 5%-40% centrality, about 8400 H/Λ 3 and 5200 H/Λ 4 candidates are reconstructed through two- and three-body decay channels. We observe that these hypernuclei exhibit significant directed flow. Comparing to that of light nuclei, it is found that the midrapidity v1 slopes of H/Λ 3 and H/Λ 4 follow baryon number …

Beam Energy Dependence Of Fifth- And Sixth-Order Net-Proton Number Fluctuations In Au + Au Collisions At Rhic, Star Collaboration

Physics and Astronomy Faculty Publications

We report the beam energy and collision centrality dependence of fifth and sixth order cumulants (C5, C6) and factorial cumulants (κ5, κ6) of net-proton and proton number distributions, from center-of-mass energy (sNN) 3 GeV to 200 GeV Au+Au collisions at RHIC. Cumulant ratios of net-proton (taken as proxy for net-baryon) distributions generally follow the hierarchy expected from QCD thermodynamics, except for the case of collisions at 3 GeV. The measured values of C6/C2 for 0%-40% centrality collisions show progressively negative trend with decreasing energy, while it is positive for the lowest energy studied. These observed negative signs are consistent with …

Cavity Induced Collective Behavior In The Polaritonic Ground State, Vasil Rokaj, Simeon I. Mistakidis, H. R. Sadeghpour

Physics Faculty Research & Creative Works

Cavity Quantum Electrodynamics Provides An Ideal Platform To Engineer And Control Light-Matter Interactions With Polariton Quasiparticles. In This Work, We Investigate Collective Phenomena In A System Of Many Particles In A Harmonic Trap Coupled To A Homogeneous Cavity Vacuum Field. The System Couples Collectively To The Cavity Field, Through Its Center Of Mass, And Collective Polariton States Emerge. The Cavity Field Mediates Pairwise Long-Range Interactions And Enhances The Effective Mass Of The Particles. This Leads To An Enhancement Of Localization In The Matter Ground State Density, Which Features A Maximum When Light And Matter Are On Resonance, And Demonstrates A …

Using Spectroscopy Of Diatomic Molecules To Search For Physics Beyond The Standard Model, Sean Jackson

Pomona Senior Theses

This main focus of this thesis is the use of molecular spectroscopy in the search for New Physics. Diatomic molecules offer interesting experimental opportunities in the search for physics beyond the Standard Model, including CP-violations due to the electric dipole mo- ment of the electron and other parity non-conservation effects. The work presented here concentrates mainly on the PbF molecule. Due to its large internal electric field, low sen- sitivity to external magnetic fields, and the presence of low-lying states of opposite parity in the 207PbF isotopolgue, PbF remains a compelling candidate for parity non-conservation studies. A robust global fit …

Homopurine Guanine-Rich Sequences In Complex With N-Methyl Mesoporphyrin Ix Form Parallel G-Quadruplex Dimers And Display A Unique Symmetry Tetrad, Ming Ye, Erin V. Chen, Shawn H. Pfeil, Kailey N. Martin, Tamanaa Atrafi, Sara Yun, Zahara Martinez, Liliya A. Yatsunyk

Physics & Engineering Faculty Publications

DNA can fold into G-quadruplexes (GQs), non-canonical secondary structures formed by pi-pi stacking of G-tet-rads. GQs are important in many biological processes, which makes them promising therapeutic targets. We identified a 42-nucleotide long, purine-only G-rich sequence from human genome, which contains eight G- stretches connected by A and AAAA loops. We divided this sequence into five unique segments, four guanine stretches each, named GA1-5. In order to investigate the role of adenines in GQ structure formation, we per-formed biophysical and X-ray crystallographic studies of GA1-5 and their complexes with a highly selective GQ ligand, N-methyl mesoporphyrin IX (NMM). Our data …

High-Dynamic-Range And High-Efficiency Near-Eye Display Systems, En-Lin Hsiang

Electronic Theses and Dissertations, 2020-2023

Near-eye display systems, which project digital information directly into the human visual system, are expected to revolutionize the interface between digital information and physical world. However, the image quality of most near-eye displays is still far inferior to that of direct-view displays. Both light engine and imaging optics of near-eye display systems play important roles to the degraded image quality. In addition, near-eye displays also suffer from a relatively low optical efficiency, which severely limits the device operation time. Such an efficiency loss originates from both light engines and projection processes. This dissertation is devoted to addressing these two critical …

Structural And Magnetic Properties Of Heusler Alloys: Fecrmn1-Xvxal (X = 0, 0.5, 0.75), Jax Wysong, Gavin Baker

The Journal of Undergraduate Research

Heusler alloys are important to investigate due to their multiple interesting properties including half-metallicity and spin-gapless semi conductivity. Materials exhibiting these properties are desired for spin-transport-based devices. These devices provide the storing and delivering of information through the utilization of the spin property of electrons. The magnetic and electronic band properties of these alloys can be modified by tuning the elemental composition. This work investigates structural and magnetic properties of the three Heusler alloys FeCrMnAl, FeCrMn_0.5V_0.5Al, and FeCrMn_0.25V_0.75Al. It was found that all three alloys crystallize in cubic crystal structure with an …

Stratospheric Glider Measurements Of Atmospheric Parameters, Anisa Haghighi

Theses and Dissertations--Mechanical and Aerospace Engineering

In June 2021 a series of high altitude flights were conducted in Spaceport America, NM, using a balloon launched Uncrewed Aircraft System (UAS) to assess its capability to conduct measurements of various atmospheric properties and study turbulence in the troposphere and lower stratosphere. This UAS descends using an automated flight trajectory. The instruments aboard included a NASA-developed infrasonic microphone to evaluate its remote turbulence detection capabilities and a five-hole probe capable of measuring the in situ wind vector. Also on board were temperature, humidity and wind profile sensors. This document focuses on the atmospheric properties measured at high altitudes, the …

Exploration And Synthesis Of Half-Heusler And Disordered Ternary Intermetallic Single Crystals, Md Fahel Bin Noor

Graduate Theses/Dissertations

Due to their distinct physical and chemical characteristics, half-Heusler compounds are intermetallic materials that have undergone substantial research. The general formula for these compounds is XYZ, where X and Y are transition metals and Z is a p-block element. Thermoelectricity is among the half-Heusler compounds' most exciting potential uses, but additional possible applications include spintronics, magnetic refrigeration, and superconductivity, among others. Recently, half-Heuslers (and Heuslers) have emerged as candidates for catalysts for hydrogenation. The CoNbSn half-Heusler compound, as well as another unique intermetallic ternary compound, the disordered Mn_4-xCr_xAl₁₁, were successfully grown as single crystals …

Synthesis And Characterization Of Cage-Structured Compounds As Promising Thermoelectric Materials, Nusrat Yasmin

Graduate Theses/Dissertations

The development of new thermoelectric materials is of great interest due to their potential to convert waste heat into useful electricity. The primary problem is that the physical factors that are utilized to assess thermoelectric performance conflict with one another. One way to improve their performance is to hinder the lattice from conducting heat through its vibrations while maintaining the heat conduction via the electrons. This can be done by creating cage structures that allow heavy atoms to jiggle. In this study, we report the synthesis of a group of such compounds, using the self-flux method. They all belong to …

On The Gaussian-Core Vortex Lattice Model For The Analysis Of Wind Farm Flow Dynamics, Apurva Baruah

Dissertations, Master's Theses and Master's Reports

Wind power science has seen tremendous development and growth over the last 40 years. Advancements in design, manufacturing, installation, and operation of wind turbines have enabled the commercial deployment of wind power generation systems. These have been due, in a large part, to the expertise in the simulation and modeling of individual wind turbines. The new generation of wind energy systems calls for a need to accurately predict and model the entire wind farm, and not just individual turbines. The commercial deployment of these wind farms depends on model's ability to accurately capture the different physics involved, each at its …

Fabrication And Optical Properties Of Two-Dimensional Transition Metal Dichalcogenides, Manpreet Boora

Dissertations, Master's Theses and Master's Reports

Two-dimensional layered materials such as graphene and transition metal dichalcogenides have gained a lot of attention because of their distinctive chemical, optical, and electronic properties. Transition metal dichalcogenides can have a tunable bandgap in the range of 1 − 3 eV (visible), which enables their applications in ultrathin field effect transistors, photovoltaics, sensors, and optoelectronic devices. They exhibit an indirect-to-direct band gap transition when thinned down from bulk to a single layer. They show strong photoluminescence, electron–photon interaction, valley pseudospin, nonlinear optical response, and lack of dangling bonds. Many exotic phenomena appear when materials are thinned to nanoscale size because …

Physical, Optical, And Chemical Properties Of Light Absorbing Aerosols And Their Climatic Impacts, Susan Mathai

Dissertations, Master's Theses and Master's Reports

Aerosols are particles suspended in the atmosphere; they are emitted during natural phenomena such as dust storms, wildfires, and volcanic eruptions, and during anthropogenic activities like household wood burning, vehicles operations, and industrial productions, or they can form in the atmosphere from gas to particle partition. Aerosols impact earth’s weather and climate by absorbing and scattering the incoming solar and the outgoing earth thermal radiation and interacting with clouds. The optical properties of aerosols evolve as the chemical and physical properties vary during their residence in the atmosphere. In addition, the aerosols’ properties strongly depend on the vertical distribution in …

An Exploration Of Cloud Droplet Growth By Condensation And Collision-Coalescence In A Convection-Cloud Chamber, Jacob T. Kuntzleman

Dissertations, Master's Theses and Master's Reports

Atmospheric clouds are crucial to weather and climate, and the rate at which droplets collide and coalesce to form precipitation is one of the fundamental controlling processes. The convection-cloud chamber allows the interactions between aerosols and cloud droplets produced by condensation to be investigated within a turbulent environment. Studying the full range of microphysical conditions in atmospheric clouds is not possible, however, unless conditions for droplet growth by collision and coalescence are also achieved. In this study, we explore the conditions favorable to collision-coalescence growth in convection-cloud chambers, extending previous work on steady-state droplet size distributions due to condensation alone. …

Tracing The Most Powerful Galactic Cosmic-Ray Accelerators With The Hawc Observatory, Dezhi Huang

Dissertations, Master's Theses and Master's Reports

Since Victor Hess's groundbreaking detection of cosmic rays in the Earth's atmosphere in 1912, the origins of these charged particles have remained an enduring mystery. Recent studies suggest that these cosmic rays are accelerated beyond Peta electronvolts by powerful astrophysical sources within our own galaxy. While the cosmic rays themselves are being deflected in all directions by magnetic fields, the gamma rays produced by them, being electrically neutral, travel to the observer in a straight line. They carry crucial information, allowing us to trace cosmic-ray accelerators within our galaxy. The High Altitude Water Chrenkov (HAWC) Observatory, located on the slopes …

Diffusion Of Carbon Nanoparticles Intercalated Into Layered Materials, Madelyn Johnson

Honors Program Theses

Using electron beam radiation, as found in a scanning electron microscope, it is possible to induce the local intercalation of carbon nanoparticles into two dimensional layered materials. This technique can be used to form insulating and optically active nanostructures in samples ranging from graphite to BSSCO. In this study, the evolution of these features with time is explored to determine the stability of such nanoparticles in layered materials.

Over the course of days and weeks, the nanostructures created this way broaden and change height. In general, it appears that material buried deep within the layers diffuses upwards to increase the …

Optical Tweezers: Exerting Force With Light, Gabriella Seifert

Scripps Senior Theses

Photons carry momentum. When a tightly-focused beam of photons hit a particle, they transfer some of their momentum to the particle, exerting a force. Optical tweezers take advantage of this phenomenon to trap (or “tweeze”) a spherical bead just after the focus of a diverging laser beam, creating a potential well that pulls in beads. In this thesis, I predict the force exerted on trapped beads and measure the actual force using an optical tweezers setup that I built. To predict the force, I follow the path of all possible rays from a diverging beam incident on a spherical bead …

The Lagrangian Formulation For Wave Motion With A Shear Current And Surface Tension, Conor Curtin, Rossen Ivanov

Articles

The Lagrangian formulation for the irrotational wave motion is straightforward and follows from a Lagrangian functional which is the difference between the kinetic and the potential energy of the system. In the case of fluid with constant vorticity, which arises for example when a shear current is present, the separation of the energy into kinetic and potential is not at all obvious and neither is the Lagrangian formulation of the problem. Nevertheless, we use the known Hamiltonian formulation of the problem in this case to obtain the Lagrangian density function, and utilising the Euler-Lagrange equations we proceed to derive some …