Physics Commons^™

A Field-Programmable Metamaterial Using Memristor As A Stable Switcher, Taekuk Hong

Theses and Dissertations

Before the memristor was discovered, there were RLC circuits as representative passive devices. However, the fourth fundamental two-terminal circuit has been discovered by Dr. Leon Chua in 1971 and has been called a memristor. The memristor is a compound word of memory and resistor, and is an element whose resistive value is not constant and whose resistive value changes depending on the applied voltage and is recorded as a memory. It is mainly used in resistive switching and is the center of this research theme. A metamaterial is artificially created material that has never been found in nature. The theory …

A Method For Single-Particle Magnetic Particle Spectroscopy With A Nanofabricated Coplanar Stripline, Jacob Martin

Theses and Dissertations

Drawing from magnetic particle imaging principles, magnetic particle spectroscopy (MPS) serves as a valuable tool employing superparamagnetic iron-oxide nanoparticles (SPIONs) in diverse applications ranging from medical imaging to biosensing and the comprehensive study of magnetic particles’ characteristics. MPS leverages the nonlinear response exhibited by SPIONs when a external magnetic field is applied, enabling a highly sensitive method for examining biological systems and more. However, conventional MPS setups demand a high particle concentration of approximately 10^15 particles per liter to generate a detectable response. The first objective of this work is to simulate the dynamics of a system with the ability …

Recovering Lost Exposure From The Majorana Demonstrator And Testing Data Selection Assumptions, Thomas Lannen

Theses and Dissertations

The Majorana Demonstrator recently concluded its search for neutrinoless double beta decay using an array of up to 40.4kg of germanium detectors, 27kg of which were enriched in ⁷⁶Ge and housed inside a copper and lead compact shield located at the 4850 foot level in a clean room in the Davis Campus of the Sanford Underground Research Facility (SURF) in Lead, South Dakota. This search proceeded from June 26, 2015 until March 3, 2021 and 64.5 kg yr of enriched active exposure was acquired while achieving a world leading energy resolution of 0.12% FWHM at 2039 keV, one of …

Measurement Of The Total Cross-Section Of Muon Neutrino Charged-Current Coherent Pion Production In Nova Near Detector, Kuruppumullage Don Chatura Dilshan Kuruppu

Theses and Dissertations

Charged Current (CC) coherent neutrino-nucleus pion production is characterized by small momentum transferred to the nucleus, which is left in its ground state. Despite the relatively large uncertainties on the production cross-section, coherent production of mesons by neutrinos represents an important process, as it can shed light on the structure of the weak current and can also constitute a potential source of background for modern neutrino oscillation experiments and searches for Beyond Standard Model (BSM) physics. This Ph.D. thesis presents a new measurement of CC coherent pion production in the NOvA near detector at the Fermi National Accelerator Laboratory (Fermilab). …

Yield Extraction For The Γd → Λ X Reaction, K H P Nishadi Hasarangi Silva

Theses and Dissertations

Improving and adding new experimental measurements of hyperon-nucleon (YN) and hyperon-deuteron (Yd) cross sections is an active area in nuclear physics research. Scientists use such cross-section data to understand the composition of neutron stars and develop a comprehensive picture of the baryon-baryon interaction. Using high luminosity photon beam incident on a long liquid deuterium target and the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility (JLab), a sample of hyperon-deuteron elastic scattering events was previously identified. The E06-103 (g13) experiment was originally designed to address the scarcity of experimental data on hyperon photoproduction off the neutron …

Gamma Calibration Of Scintillators For The Muon Scattering Experiment, Anne Gloria Flannery

Theses and Dissertations

The MUon Scattering Experiment (MUSE) at the Paul Scherrer Institute seeks to measure the muon-proton and electron-proton elastic cross-sections in the same experiment by measuring the scattering angle of particles from a 115-160 MeV beam onto a liquid hydrogen target. The timing detectors, as well as several of other detectors in the experiment, are plastic scintillators. This document discusses a method for the energy calibration, using ²⁰⁸Tl, ²²Na, and 88Y sources, signal attenuation, and hit-position reconstructions of various timing detectors, as well as their function in the experiment as a whole. This method involves first attaining the pulse-height …

Muon Intensity Measurement With The Majorana Demonstrator, Franklin Michael Adams Jr.

Theses and Dissertations

The Majorana Demonstrator (MJD) is a shielded radiation detection system located a mile underground at the Sanford Underground Research Facility (SURF) in South Dakota. The system aims to detect the theorized, rare process of neutrinoless double-beta decay. The Demonstrator utilizes an array of scintillating acrylic detectors to veto any signals induced by earth-penetrating cosmogenic muons and reach background levels necessary for the detection of neutrinoless double-beta decay. Utilizing the data collected by the muon veto system, an analysis has been done to determine the differential muon intensity. The complex geometry of the interlacing detector panels requires the use of Monte …

A Study Of Single Molecule Detection With Graphene Hall Bars, Kenneth Stephen Stephenson

Theses and Dissertations

In 2007, detection of individual molecules with a solid-state gas sensor was reported for first time by Schedin et al. where they used micromechanically-cleaved graphene for their sensing material, which exhibits isotropic and homogeneous conduction [1]. However, despite the novelty and popularity of their work, it has never been repeated. Further, we found their associated calculations to be self-inconsistent by a factor of 103 . So, hoping to account for and resolve this discrepancy, we outline the plan we had to reproduce their experiment. We also justify any substantial modifications, particularly our choice to use epitaxial graphene instead. Then, we …

Sensitivity Of The Cupid Experiment To Bragg-Primakoff Conversion Of Solar Axions And Alps, Kevin P. Wilson

Theses and Dissertations

The author reports in this dissertation on the application of a technique to use bolometer detector arrays, such as those of the CUORE experiment and its proposed upgrade CUPID, to search for 14.4 keV Solar axions arising from an M1 nuclear transition of thermally excited ⁵⁷Fe in the Solar core. Density functional theory calculations performed using QU A N T U M ESPRESSO for Li₂MoO₄ enable the computation of a time-dependent axionto-photon conversion rate in the bolometer crystals. These calculations predict that the proposed CUPID detector will be sensitive to Solar axions or axion-like particles that …

Memristive Ising Circuits, Vincent James Dowling

Theses and Dissertations

Resistance random access memory (ReRAM) cells are emerging passive components showing great promise for applications in non-volatile storage, in-memory computing, and neuromorphic circuits, to name a few. Various experimental ReRAM cells have demonstrated excellent characteristics. This includes nanoscale size, short read and write times, and small energy requirements needed to manipulate the information. The main obstacles preventing the widespread adoption of ReRAM technology are significant device-to-device and cycle-to-cycle variability.

In essence, ReRAM cells are resistors with memory whose state (resistance) can be changed by an applied signal such as voltage. Many models were developed for describing their response. These range …

Search For Triple-Proton Decay Using Machine Learning With Cuore, Douglas Adams

Theses and Dissertations

A framework to search for a triple-proton decay of ¹³⁰Te in the CUORE detector against a background of muons is presented. We use machine learning to classify different kinds of energy depositing events. We use the classification information to improve our detection or non-detection limits of a triple-proton decay process. We derive and use a methodology of combining Poisson counting statistics with supervised classification machine learning tools. Additionally, a sensitivity calculation is provided which uses the classification counting likelihood. Using our analysis technique, we achieve an lower 2σ half-life bound of 7.43×10²⁴yrs for triple-proton decay of …

Magnetic Field Directed Self-Assembly Of Colloidal Nanoparticles Via Extreme Field Gradients Of Magnetic Recording Media, Abdul Rahman Mohtasebzadeh

Theses and Dissertations

Magnetic nanoparticles have been extensively studied over the last half century and continue to sustain interest due to their potential use in different fields. This research explores Magnetic Field Directed Self-Assembly of magnetic nanoparticles using a magnetic disk drive. The magnetic fields generated by the bits in a magnetic disk drive have rapidly changing field gradients that can self-assemble magnetic nanoparticles into various shapes. We demonstrate the ability to record and read field gradients on a commercial disk drive medium and to use monodisperse iron oxide nanoparticles to achieve self-assembly. We use image analysis techniques to quantify parameters related to …

Study Of Radiative Corrections In The Muon Scattering Experiment, Lin Li

Theses and Dissertations

The root-mean-square (rms) radius of the proton charge is a fundamental quantity. In 2010, the studies of muonic hydrogen with high precision found a notably smaller value than the one from earlier non-muonic measurements. This discrepancy has led to theoretical and experimental investigations. A missing measurement in determining the proton radius is muon scattering, a measurement that the MUon Scattering Experiment (MUSE) collaboration proposed at Paul Scherrer Institute (PSI). MUSE will measure elastic electron-proton and muon-proton scattering data with positively and negatively charged beams in a four-momentum-transfer square range from Q2 = 0.002 to 0.08 GeV² . Each of …

Application Of The Test For Memristor To Experimental Memory Devices, Jinsun Kim

Theses and Dissertations

In early seventies, the memristor was introduced as the fourth fundamental nonlinear two-terminal circuit element coupling the charge and flux by Dr. L. Chua. In 2008, the experimental discovery of the memristor was announced triggering significant interest in the development of resistance switching memory devices and their applications. According to Chua, the pinched hysteresis loop in the current-voltage characteristic of experimental memory devices is the fingerprint of memristors (“if it’s pinched it’s a memristor”). However, such loops are not an exclusive feature of memristors as they are also found in the response of other devices with memory that are not …

Shedding Light On The Coupling Dynamics In Hybrid Nanostructures, Saba Arash

Theses and Dissertations

Here we present all-optical investigations of two hybrid nanostructures. In the first hybrid system, we study Janus-type nanofibers consisting of two hemi-cylinders of ferroelectric barium titanate and ferrimagnetic cobalt ferrite. Using the magnetic field-dependent polarization-resolved second harmonic generation technique, we observe a strong magnetoelectric coupling between the two ferroic constituents at room temperature. Corroborating these results by X-ray diffraction, we can also extract repeatable memory-dependent behaviors in these biphasic nanofibers. In the second hybrid system, we study the interaction between the semiconductor indium/gallium arsenide quantum dots and surface plasmon supporting silver structures in the weak coupling regime. When quantum dots …

Π+Π- Electroproduction Off Protons In Deuterium: Measurements Of Quasi-Free Cross Sections And Kinematic Probing Of Final State Interactions, Iuliia Skorodumina

Theses and Dissertations

In this study, the process of π⁺π^- electroproduction off protons bound in deuterium nuclei is explored. The exploration is performed through the analysis of experimental data on electron scattering off the deuteron target, collected in Hall B at Jefferson Lab with the CLAS detector. As a main result, the set of integrated and single-differential cross sections of the reaction $\gamma_{v}p(n) \rightarrow p' (n')\pi^{+}\pi^{-}$ is obtained. The cross sections are extracted in the quasi-free regime, which implies that only events not affected by final state interactions are subject to selection. The measurements are performed in the kinematic region …

Large-NC Constraints For One- And Two-Nucleon Currents In Effective Field Theory, Thomas Richardson

Theses and Dissertations

There is a long-standing goal of understanding nuclear physics in terms of quarks and gluons, the constituent particles of nucleons. However, the underlying theory is strongly coupled at the scales relevant for nuclear physics; therefore, this goal can only be achieved through nonperturbative calculations. Additionally, nuclear targets are employed in a variety of experiments ranging from electroweak processes to Beyond the Standard Model physics. Thus, it is important to have a strong theoretical foundation for nuclear physics in the presence of external fields in order to interpret experimental results. Effective field theory (EFT) for nuclear physics constitutes a systematic and …

Two Aspects Of Magnetic Nanoparticle Self-Assembly On Thin-Film Multilayers: Custom Media Properties And Accurate Determination Of Nanoparticle Anisotropy Constant, Sara L. Fitzgerald

Theses and Dissertations

ZFC/FC moment versus temperature measurements are a common technique to determine magnetic properties of nanoparticles. In this work, I varied both applied field strength and nanoparticle concentration to study resulting changes in blocking temperature, T_B, and anisotropy constant, K. T_B and K values were obtained using both existing and new analytic methods. Accurate determination of these parameters helps researchers optimize the use of magnetic nanoparticles for a variety of applications, including magnetic heating, drug delivery, and magnetic field-directed self-assembly. For magnetic self-assembly particularly, not only nanoparticle properties, but also the magnetic properties of the substrate alter …

Measurement Of N* Cross-Sections From Single-Pion Electroproduction At Low Q^2, Nicholas Scoville Tyler

Theses and Dissertations

Measurements of nucleon electroexcitation resonance cross-sections give unique insight into the dynamics of the strong interaction and our knowledge of Quantum Chromodynamics (QCD). The analysis of exclusive electroproduction data is an important tool in understanding the structure of the nucleon and its excited states. Exclusive channels give a clear way to extract the desired resonant contributions from non-resonant contributions. A gap in the helicity amplitudes extracted from single-pion cross-section data exists for virtual photon momentum transfers ($Q^2$) in the range of $1-2~\mathrm{GeV}^{2}$. Using data collected by the CEBAF Large Acceptance Spectrometer (CLAS) detector with a beam energy of $4.8~\mathrm{GeV}$, the …

Expanding The Frontiers Of Supernova Cosmology In Preparation For Next Generation Telescopes, Justin Roberts-Pierel

Theses and Dissertations

Supernova (SN) research has been the source of many astronomical discoveries over the past several decades, most prominently the accelerated expansion of the universe by so-called “dark energy” in 1998. Next generation surveys like the Vera C. Rubin Observatory and the Nancy G. Roman Space Telescope, in large part through traditional luminosity distance measurements with Type Ia supernovae (SNe Ia), are set to reveal more about the nature of dark energy this decade than at any time in history. The enormous SN Ia samples from Roman and Rubin mean cosmological inferences will no longer be limited by statistical uncertainties, …

Measuring Strain-Mediated Magnetoelectric Effects In Magnetically Self-Assembled Multiferroic Janus Nanofiber Chains: A Quest For New Techniques To Study Multiferroic Nanomaterials, Bryan Lucas Chávez

Theses and Dissertations

Bi-phasic composite multiferroics couple piezoelectric and magnetostrictive proper- ties via an interfacial strain, allowing for control of their magnetic properties with electric fields and vice versa. Nanofibers have a larger area-to-volume ratio than thin films and are not affected by substrate clamping, leading to a predicted magnetoelec- tric coupling an order of magnitude higher than those found in thin-film multiferroics. Nanofibers have potential applications in photonics, nanoelectronics, biosensing, and optoelectronics. This work focuses on measuring magnetoelectric effects in electro- spun nanofibers made of barium titanate (BaTiO₃) and cobalt ferrite (CoFe₂O₄). To transform the disordered …

Feasibility Study Of ΛD Elastic Scattering In Data From Photoproduction Off Deuteron, Brandon Steven Tumeo

Theses and Dissertations

Experimental observables for hyperon-deuteron (Yd) scattering are important in the study of the YN interaction and, especially, the YNN three-body interaction. YN scattering experiments are difficult and lacking due to the short lifetime of hyperons. Currently, there is a very limited database for YN elastic scattering cross-sections, and there is no data on Yd elastic scattering cross-sections. The high-luminosity Jefferson Lab experiment E06-103 (g13), in which a real-photon beam was incident on a 40-cm- long liquid deuteron target, offers a unique opportunity to look for hyperon-deuteron elastic scattering signal, Λd being the most promising. In such a dataset, the Λ …

Fermi-Unsmearing In Single Charged Pion Electroproduction Cross-Section Measurements For The Neutron And Proton In Deuterium, Gary Hollis

Theses and Dissertations

Electron scattering cross-sections for two different reaction channels, e- + p→ e- + n + ϖ + and e- + n → e- + p ϖ - using an unpolarized deuterium target, were extracted from Jefferson Lab experiment E1E data with a beam energy of 2.039 GeV, providing a (W;Q2) coverage of 1.1 GeV < W < 1.9 GeV and0.4 GeV2< Q2 2. Although there has already been an analysis of this same data set for the second reaction channel listed above [1], more of the cross-section domain has been covered in this analysis due to applying a new technique called Fermi-unsmearing. Fermi-smearing is a distortion in a cross-section measurement which occurs whenever the target is erroneously assumed to be at rest but is in fact a bound nucleon as part of a larger nucleus (and thus is in Fermi-motion). Fermi-unsmearing is a Monte Carlo method presented in this work for generating a correction factor that removes the Fermi-smearing effect from an existing cross-section measurement that suffers from Fermi-smearing. Using Fermi-unsmearing can have the advantage of significantly larger statistical sample sizes given the same data set due to allowing less strict final data selection criteria, as occurs in a Fermi-unsmeared analysis of the e- + n→ e- + p + ϖ- channel in contrast to a fully-exclusive analysis of the same channel. The same Fermi-unsmearing method is applied to the first channel after having established the efficacy of the method using the second channel.

Methods For Cancellation Of Apparent Cerenkov Radiation Arising From Sme Models And Separability Of Schrödinger’S Equation Using Exotic Potentials In Parabolic Coordinates, Richard Henry Decosta

Theses and Dissertations

In an attempt to merge the two prominent areas of physics: The Standard Model and General Relativity, there have been many theories for the underlying physics that may lead to Lorentz- and CPT-symmetry violations. At the present moment, technology allows numerous types of Planck-sensitive tests of these symmetries in a range of physical systems.

We address a curiosity in isotropic CPT- and Lorentz-violating electrodynamics where there is a kinematic allowance for Cerenkov radiation of a charged particle in a vacuum moving with uniform motion. This however, should not be the case as it is known that constant motion in a …

Cosmic Metal Evolution During The First ∼1 Billion Years After The Big Bang Using Damped/Sub-Damped Lyman-Alpha Absorbers, Suraj Poudel

Theses and Dissertations

Metal abundance measurements throughout the cosmic ages track the history of galaxy formation and evolution. Measuring abundances during the first ∼1 billion years is especially important, as they are influenced by the nucleosynthetic signatures from the early stars. Evolution of metallicity of Damped/sub-Damped Lyman-alpha Absorbers (DLAs/sub-DLAs) detected in the spectra of quasars is a powerful tracer of the cosmic star formation history. A sudden drop in DLA metallicity at z>4.7 was reported in some recent studies. However, these studies were primarily based on refractory elements such as Fe and Si. We present ten new abundance measurements of the elements …

Neutrino Induced Coherent-Pion: Precision Measurement In Nomad And Uses In Oscillation Experiments, Bing Guo

Theses and Dissertations

In the era of high precision oscillation measurements, lead by DUNE and Hyper-K, the Near Detector (ND) faces unprecedented challenges and opportunities. Among the various neutrino events in ND, Coherent meson production plays a special role. It is a non-negligible background to the oscillation signal. However the cross-section models for neutrino induced Coherent meson currently being used are old and imprecise. On the other hand, Coherent meson has a simple experimental signature with minimal nuclear effect making it unique among neutrino-nucleon interactions. Furthermore, the cross section for Coherent meson is the same in neutrino and antineutrino modes. It, thus, potentially …

What Can Scattered Light Tell You About Your Favorite Magnetic Material?: A Magneto Optical Investigation Of The Magnetic Properties Of Aligned Janus Fiber Agglomerates.Influence Of Dynamic Multiaxial Transverse Loading On Ultrahigh Molecular Weight Polyethylene Single Fiber Failure, Cory John Dolbashian

Theses and Dissertations

Here we seek to take a traditional Magneto Optic Kerr Effect (MOKE) experimental design, useful for local magnetization measurements, and apply it to measuring aligned multiferroic Janus nano fiber agglomerates. In order to achieve this we modify the traditional MOKE geometry by measuring our Kerr rotation from collimated scattered light, rather than the conventional specular reflection. Using various techniques to improve signal to noise ratio (SNR), we extend the application of this scattered MOKE geometry to build families of First Order Reversal Curves (FORC). Using an alternative analysis technique, FORC curves are processed and become a FORC diagram, which is …

Probing The Interstellar Medium Of Galaxies Using Gravitationally Lensed Sight Lines And The Relevant Atomic Physics, Frances Cashman

Theses and Dissertations

Absorption spectroscopy of gravitationally lensed quasars (GLQs) enables study of spatial variations in the interstellar and/or circumgalactic medium (ISM, CGM) of foreground galaxies. In this work I present observations of 4 GLQs, each with two images separated by 0.8-3.000, that show strong absorbers at redshifts 0.4 abs< 1.3 in their spectra, including some at the lens redshift. The H I Lyman lines were measured in five absorbers using HST-STIS, and metal lines with either the MagE spectrograph or the Sloan Digital Sky Survey. These data, combined with the literature, show no strong correlation between absolute values of differences in NH I, NFe II, or [Fe/H] and sight line separations at absorber redshifts. The measured abundance gradients show a tentative anti-correlation with abundances at galaxy centers.

A study of the lens galaxy foreground to the doubly lensed quasar SBS 0909+532 reveals a large difference in H I and metal column densities between sight lines. Using archival HST-STIS and Keck HIRES spectra, log N _{H I} 18.18 cm−2 and log N _{H I} = 20.38±0.02 cm⁻²were measured, resulting …

A Model Independent Measurement Of The Cross Section Ratio, R_Σ = Σ(Ν_Μ N → Μ^− P) / Σ(Ν_Μ N → 2track), Barnali Chowdhury

Theses and Dissertations

NOνA (NuMI Off-Axis νe Appearance) experiment is a long-baseline neutrino and anti-neutrino oscillation experiment, designed to study the neutrino mass ordering and to search for the effects of the CP violating phase angle δ. Extraction of the νµ and νe oscillation parameters requires knowledge of the energy of the neutrino interacting in the detector. The reactions of neutrinos with matter produce charged and neutral particles in the detector. How well we are able to measure the energy of the incoming neutrino is directly related to the final state particles, seen in the detector. Inaccurate …

Non-Local Spin Valve Interferometer: Experimental Observation Of Superconducting Spin Current And Spin Aharonov-Bohm Effect, Ning Lu

Theses and Dissertations

An electron interferometer was designed and fabricated via a normal metal (supercon- ductor)/insulator/ferromagnet non-local lateral spin valve with a ring-shaped normal metal/insulator spacer, and spin current interference was observed. At 4.2 K, a very high spin signal of 200 mΩ was found in a device with 2 µm injector-detector dis- tance and magnetic field swept parallel to the plane. With a perpendicular magnetic field sweep, a Hanle effect measurement showed both spin precession and h/e oscil- lation. Because of the non-adiabatic nature of the precessing spins at low fields as they traverse the normal metal ring, this is an …