Digital Commons Network^™

Developing Positive Thermal Coefficient (Ptc) Heaters For Solar Electric Cooking, Katarina Ivana Brekalo, Andrew Shepherd

Physics

Positive Thermal Coefficients, PTCs, are materials that abruptly change in resistance in response to changes in temperature. The purpose of this experiment is to explore the viability of using the switching type ceramic PTC thermistor as a replacement for current resistive heaters. These types of PTCs have a nonlinear change in resistance with increases in temperature. This device will be used as a temperature-controlling heating element intended to power an Insulated Solar Electric Cooker (ISEC). The ISEC is designed to cook meals throughout the day for impacted communities as an alternative cooking method that doesn’t require biofuel as an energy …

Developing An Error Budget For The Creation Of A Multi-Layer Thin Film, Samantha Weckerly

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

An Inexpensive Maximum Power Point Tracking System For An Insulated Solar Electric Cooker Using An Off-The-Shelf Buck Converter, Andrew A. Perez

Physics

A specialized control circuit using an off-the-shelf buck converter is built for an Insulated Solar Electric Cooker (ISEC). Cost and efficient power delivery are the focus. An ISEC is synonymous to a direct load heat resistor, allowing a specific maximum power point tracking (MPPT) algorithm and fewer components. Only a microcontroller, voltage sensor, and digital-to-analog converter are used with the buck converter to maximize the power delivered by a 100W solar panel for the 3.3Ω load.

Polarization Switching In Gold Nanostructure Array, Harrison Knox

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Electromagnetic Wave Absorption Of Coconut Fiber-Derived Porous Activated Carbon, Jemilat Yetunde Yusuf, Hassan Soleimani, Noorhana Yahya, Yekinni Kolawole Sanusi, Gregory Kozlowski, Andreas Öchsner, Lawal Lanre Adebayo, Fatai Adisa Wahaab, Surajudeen Sikiru, Bashiru Bolaji Balogun

Physics Faculty Publications

In this study, porous carbon has been prepared through potassium hydroxide (KOH) activation of coconut fiber (CF) and subsequent carbonization in the presence of an inert gas. The activated carbons (AC) were prepared via carbonization of the precursor at different temperatures. Subsequently, their electromagnetic wave absorption (EMWA) performance was investigated at X-band frequency. The phase crystallinity, porous features, and degree of graphitization of the activated carbons were studied using XRD, nitrogen adsorption/desorption isotherm, and Raman spectroscopy, respectively. Using the BET method, the activated carbon prepared at 750 °C displayed a high specific surface area of 602.9 m2 g−1 and an …

Synthesis Of Metastable Ruddlesden–Popper Titanates, (ATio3)NAO, With N ≥ 20 By Molecular-Beam Epitaxy, Matthew R. Barone, Myoungho Jeong, Nicholas Parker, Jiaxin Sun, Dmitri A. Tenne, Kiyoung Lee, Darrell G. Schlom

Physics Faculty Publications and Presentations

We outline a method to synthesize (ATiO₃)_nAO Ruddlesden–Popper phases with high-n, where the A-site is a mixture of barium and strontium, by molecular-beam epitaxy. The precision and consistency of the method described is demonstrated by the growth of an unprecedented (SrTiO₃)₅₀SrO epitaxial film. We proceed to investigate barium incorporation into the Ruddlesden–Popper structure, which is limited to a few percent in bulk, and we find that the amount of barium that can be incorporated depends on both the substrate temperature and the strain state of the …

Constraints On The Very High Energy Gamma-Ray Emission From Short Grbs With Hawc, A. Albert, R. Alfaro, C. Alvarez, J. C. Arteaga-Velázquez, K. P. Arunbabu, D. Avila Rojas, H. A.Ayala Solares, R. Babu, E. Belmont-Moreno, C. Brisbois, K. S. Caballero-Mora, T. Capistrán, A. Carramiñana, S. Casanova, O. Chaparro-Amaro, U. Cotti, J. Cotzomi, S. Coutiño De León, C. De Leon, E. De La Fuente, R. Diaz Hernandez, S. Dichiara, B. L. Dingus, M. A. Duvernois, M. Durocher, J. C. Diaz-Velez, K. Engel, C. Espinoza, K. L. Fan, N. Fraija, A. Galvan-Gamez, J. A. Garcia-Gonzalez, F. Garfias, M. M. Gonzalez, J. A. Goodman, J. P. Harding, S. Hernandez, B. Hona, D. Huang, F. Hueyotl-Zahuantitla, T. B. Humensky, P. Huntemeyer, A. Iriarte, V. Joshi, S. Kaufmann, A. Lara, W. H. Lee, H. Leon Vargas, J. T. Linnemann, A. L. Longinotti, G. Luis-Raya, K. Malone, S. S. Marinelli, O. Martinez, J. Martinez-Castro, J. A. Matthews, P. Miranda-Romagnoli, J. A. Morales-Soto, E. Moreno, M. Mostafa, A. Nayerhoda, L. Nellen, M. Newbold, R. Noriega-Papaqui, A. Peisker, Y. Perez Araujo, E. G. Perez-Perez, Z. Ren, C. D. Rho, D. Rosa-Gonzalez, M. Rosenberg, J. R. Sacahui, H. Salazar, F. Salesa Greus, A. Sandoval, J. Serna-Franco, A. J. Smith, R. W. Springer, P. Surajbali, O. Tibolla, K. Tollefson, I. Torres, R. Torres-Escobedo, R. Turner, L. Villasenor, Xiaojie Wang, E. Willox, A. Zepeda, H. Zhou

Physics Faculty Research & Creative Works

Many gamma-ray bursts (GRBs) have been observed from radio wavelengths, and a few at very high energies (VHEs, >100 GeV). The High-Altitude Water Cherenkov (HAWC) gamma-ray observatory is well suited to study transient phenomena at VHEs owing to its large field of view and duty cycle. These features allow for searches of VHE emission and can probe different model assumptions of duration and spectra. In this paper, we use data collected by HAWC between 2014 December and 2020 May to search for emission in the energy range from 80 to 800 GeV coming from a sample of 47 short GRBs …

Evidence For An Interaction Between The Galactic Center Clouds M0.10-0.08 And M0.11-0.11, Natalie O. Butterfield, Cornelia C. Lang, Adam Ginsburg, Mark R. Morris, Jürgen Ott, Dominic A. Ludovici

Physics and Engineering Science

We present high-resolution (∼2-3″; ∼0.1 pc) radio observations of the Galactic center cloud M0.10−0.08 using the Very Large Array at K and Ka band (∼25 and 36 GHz). The M0.10−0.08 cloud is located in a complex environment near the Galactic center Radio Arc and the adjacent M0.11−0.11 molecular cloud. From our data, M0.10−0.08 appears to be a compact molecular cloud (∼3 pc) that contains multiple compact molecular cores (5+; <0.4 pc). In this study, we detect a total of 15 molecular transitions in M0.10−0.08 from the following molecules: NH3, HC3N, CH3OH, HC5N, CH3CN, and OCS. We have identified more than sixty 36 GHz CH3OH masers in M0.10−0.08 with brightness temperatures above 400 K and 31 maser candidates with temperatures between 100 and 400 K. We conduct a kinematic analysis of the gas using NH3 and detect multiple velocity components toward this region of the Galactic center. The bulk of the gas in this region has a velocity of 51.5 km s⁻¹ (M0.10−0.08) with a lower-velocity wing at 37.6 km s⁻¹. We also detect a relatively faint velocity component at 10.6 km s⁻¹ that we attribute to being an …

Magnetoquantum Oscillations In The Specific Heat Of A Topological Kondo Insulator, Patrick G. Labarre, Andreas Rydh, J. Palmer-Fortune, J. A. Frothingham, S. T. Hannahs, Arthur P. Ramirez, Nathanael Alexander Fortune

Physics: Faculty Publications

Surprisingly, magnetoquantum oscillations (MQO) characteristic of a metal with a Fermi surface have been observed in measurements of the topological Kondo insulator SmB6. As these MQO have only been observed in measurements of magnetic torque (dHvA) and not in measurements of magnetoresistance (SdH), a debate has arisen as to whether the MQO are an extrinsic effect arising from rareearth impurities, defects, and/or aluminum inclusions or an intrinsic effect revealing the existence of charge-neutral excitations. We report here the first observation of magnetoquantum oscillations in the low-temperature specific heat of SmB6. The observed frequencies and their angular dependence for these flux-grown …

Methods For Bioconjugation Of Biochemical Sensors Based On Metallic Nanoparticles, Jacob Rolin

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Degree Of Linear Polarization: An Indicator Of Optical Vortex Beam Entanglement, Ella James

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Low-Cost Compact Optical Spectroscopy And Novel Spectroscopic Algorithm For Point-Of-Care Real-Time Monitoring Of Nanoparticle Delivery In Biological Tissue Models, Zahid Hasan, Jing Yan, Zhongchao Yi, Madison O. Korfhage, Sheng Tong, Caigang Zhu

Markey Cancer Center Faculty Publications

Objective: Real-time monitoring of nanoparticle delivery in biological models is essential to optimize nanoparticle- mediated therapies. However, few techniques are available for convenient real-time monitoring of nanoparticle concentrations in tissue samples. This work reported novel optical spectroscopic approaches for low-cost point-of-care real-time quantification of nanoparticle concentrations in biological tissue samples.

Methods: Fiber probe measured diffuse reflectance can be described with a simple analytical model by introducing an explicit dependence on the reduced scattering coefficient. Relying on this, the changes on the inverse of diffuse reflectance are proportional to absorption change when the scattering perturbation is negligible. We developed this model …

Fundamental Neutron Physics At Spallation Sources, Nadia Fomin, Jason Fry, Robert W. Pattie Jr., Geoffrey L. Greene

EKU Faculty and Staff Scholarship

Low-energy neutrons have been a useful probe in fundamental physics studies for more than 70 years. With advances in accelerator technology, many new sources are spallation based. These new, high-flux facilities are becoming the sites for many next-generation fundamental neutron physics experiments. In this review, we present an overview of the sources and the current and upcoming fundamental neutron physics programs.

Entropy Analysis Of Sutterby Nanofluid Flow Over A Riga Sheet With Gyrotactic Microorganisms And Cattaneo–Christov Double Diffusion, M. Faizan, F. Ali, K. Loganathan, A. Zaib, C. A. Reddy, Sara I. Abdelsalam

Basic Science Engineering

In this article, a Riga plate is exhibited with an electric magnetization actuator consisting of permanent magnets and electrodes assembled alternatively. This exhibition produces electromagnetic hydrodynamic phenomena over a fluid flow. A new study model is formed with the Sutterby nanofluid flow through the Riga plate, which is crucial to the structure of several industrial and entering advancements, including thermal nuclear reactors, flow metres and nuclear reactor design. This article addresses the entropy analysis of Sutterby nanofluid flow over the Riga plate. The Cattaneo–Christov heat and mass flux were used to examine the behaviour of heat and mass relaxation time. …

Enhancement Of 2d Topological Semimetal Transport Properties By Current Annealing, A. Fereidouni, M. H. Doha, K. Pandey, R. Basnet, J. Hu, H. O. H. Churchill

Physics Faculty Publications and Presentations

Observation of intrinsic quantum transport properties of two-dimensional (2D) topological semimetals can be challenging due to suppression of high mobility caused by extrinsic factors introduced during fabrication. We demonstrate current annealing as a method to substantially improve electronic transport properties of 2D topological semimetal flakes. Contact resistance and resistivity were improved by factors up to 2×10⁶ and 2×10⁴⁠, respectively, in devices based on exfoliated flakes of two topological semimetals, ZrSiSe and BaMnSb₂. Using this method, carrier mobility in ZrSiSe was improved by a factor of 3800, resulting in observation of record-high mobility for exfoliated ZrSiSe. …

Enabling Rapid Chemical Analysis Of Plutonium Alloys Via Machine Learning-Enhanced Atomic Spectroscopy Techniques, Ashwin P. Rao

Theses and Dissertations

Analytical atomic spectroscopy methods have the potential to provide solutions for rapid, high fidelity chemical analysis of plutonium alloys. Implementing these methods with advanced analytical techniques can help reduce the chemical analysis time needed for plutonium pit production, directly enabling the 80 pit-per-year by 2030 manufacturing goal outlined in the 2018 Nuclear Posture Review. Two commercial, handheld elemental analyzers were validated for potential in situ analysis of Pu. A handheld XRF device was able to detect gallium in a Pu surrogate matrix with a detection limit of 0.002 wt% and a mean error of 8%. A handheld LIBS device was …

Quantum Error Detection Without Using Ancilla Qubits, Nicolas Guerrero

Theses and Dissertations

Quantum computers are beset by errors from a variety of sources. Although quantum error correction and detection codes have been developed since the 1990s, these codes require mid-circuit measurements in order to operate. In order to avoid these measurements we have developed a new error detection code that only requires state collapses at the end of the circuit, which we call no ancilla error detection (NAED). We investigate some of the mathematics behind NAED such as which codes can detect which errors. We then run NAED on three separate types of circuits: Greenberger–Horne–Zeilinger circuits, phase dependent circuits, and a quantum …

Efficiency Quantification For Pulsed-Source Digital Holographic Wavefront Sensing, Steven A. Owens

Theses and Dissertations

The efficiencies of a digital holography (DH) system in the pulsed configuration and the off-axis image plane recording geometry are analyzed. First, the system efficiencies of an infrared-wavelength DH system in a homodyne-pulsed configuration are measured and compared to those of a visible-wavelength DH system in a homodyne-continuous-wave (CW) configuration. The total-system, excess-reference-noise, shot-noise-limit, and mixing efficiencies of the pulsed-source system were found to be consistent with those of the CW-source system. This indicated no new efficiencies were necessary to characterize pulsed-source systems when no temporal delay exists between the pulses. The consistency of efficiencies also showed infrared DH systems …

Optimizing Optical Switching Of Non-Linear Hyperbolic Metamaterials, James A. Ethridge

Theses and Dissertations

Modern optical materials are engineered to be used as optical devices in specific applications, such as optical computing. For optical computing, efficient forms of a particular device, the optical switch, still have not been successfully demonstrated. This problem is addressed in this research through the use of designed optical metamaterials, specifically, hyperbolic metamaterials, which offer the possibility of large non-linear properties with a low switching intensity. One-dimensional layered hyperbolic metamaterials composed of alternating layers of metal and dielectric were used here, with ITO as the metal and SiO₂ as the dielectric. The non-linear behavior of the ITO/SiO₂ layered …

The Separation Of Charm And Bottom Decays Measured In P+Au Collisions At 200 Gev, Zhiyan Wang

Dissertations, Theses, and Capstone Projects

It has long been observed experimentally, from previous heavy-flavor electron measurements, that heavy quarks are subject to substantial modifications of their momentum spectrum. Using the PHENIX detector at the Relativistic Heavy Ion Collider (RHIC), measurements of the production of open heavy flavor hadrons with charm and bottom quarks in p+Au collisions at 200 GeV are studied and presented in this thesis. Distance of closest approach analysis of electron tracks is used to study the semileptonic decay electrons from charm and bottom hadrons. The results include invariant yield and fraction of bottom electrons. In addition to the p+p and Au+Au collisions’ …

Driven Dipolaritons In Van Der Waals Transition Metal Dichalcogenide Heterostructures: Properties And Applications, Patrick Serafin

Dissertations, Theses, and Capstone Projects

The need for advances in optical computation leads us toward the investigation of novel methods of re-routing light in optical circuits. The behavior and properties of electrically driven exciton-dipolaritons in van der Waals transition metal dichalcogenides are investigated as a platform for realizing working elements of a polaritronic transistor. In this work, we consider exciton-dipolaritons, which are three-way superposition of cavity photons, direct excitons, and indirect excitons in a bilayer semiconducting system embedded in an optical microcavity. We start by providing motivation for our study of polaritons and then survey the fundamental properties of exciton-dipolaritons. We also survey the basic …

High Water-Responsiveness Of Peptidoglycan And Its Water-Responsive Mechanism, Haozhen Wang

Dissertations, Theses, and Capstone Projects

Water-responsive materials that reversibly deform in response to humidity changes show great potential for developing muscle-like actuators for miniature and biomimetic robotics. This thesis demonstrates that peptidoglycan exhibits ultrahigh water-responsive actuation energy and power densities, which are orders of magnitude higher than those of frequently used actuators, such as piezoelectric actuators and dielectric elastomers. Surprisingly, peptidoglycan exhibits an energy conversion efficiency of ~66.8%, which could be attributed to its super-viscous nanoconfined water that efficiently translates water’s movement to peptidoglycan’s mechanical deformation. The systematic water-responsive characterizations of peptidoglycan from different microorganisms and peptide crystals indicate that enhanced H-bonding interactions in water-responsive …

Nmr Characterization Of Novel Materials For Battery Electrolyte Applications, Sahana Bhattacharyya

Dissertations, Theses, and Capstone Projects

The extensive application of renewable and non-renewable energy storage devices in commercial products and services and the global warming have created significant motivations to accelerate research in battery technology. In addition, the risk factors generated by the high heat generation and flammability of the batteries are being addressed by inventing new renewable or non-renewable energy resources that do not release greenhouse gases into the atmosphere. This thesis discusses the applications of Nuclear Magnetic Resonance (NMR) Spectroscopy in characterizing and understanding novel battery materials as potential battery electrolytes. Works discussed include: the variable temperature characterization of water-based solid polymer electrolyte for …

Using Protonation Microstates And Hydrogen Bond Networks To Track Proton Transfer Pathways In Complex I, Umesh Khaniya

Dissertations, Theses, and Capstone Projects

Complex I, NADH-ubiquinone oxidoreductase, is the first enzyme in the mitochondrial and bacterial aerobic respiratory chain. It pumps four protons through four transiently open pathways from the high pH, negative, N- side of the membrane to the positive, P-side driven by the exergonic transfer of electrons from NADH to a quinone. Three protons transfer through subunits descended from Mrp antiporters, while the fourth, E-channel is unique. Because of the complex possible paths thorough the many buried polar residues and lack of high-resolution crystal structure, the path for protons through the E-channel is elusive.

In this dissertation, the E-channel proton pumping …

Control Of Nonlinear Properties Of Van Der Waals Materials, Rezlind Bushati

Dissertations, Theses, and Capstone Projects

Van der Waals materials are a broad class of materials that exhibit unique optoelectronic properties. They provide a rich playground for which they can be integrated into current on-chip devices due to their nanometer-scale size, and be utilized for studying fundamental physics. Strong coupling of emitters to microcavities provides many opportunities for new exotic physics through the formation of hybrid quasi-particles exciton-polaritons. This thesis
focuses on exploring and enhancing nonlinearity of van der Waals materials through strongly coupling to microcavities. By taking advantage of the stacking order of TMDs, we show intense second-harmonic generation from bulk, centrosymmetric TMD systems. In …

Topological Shadow Of Higher-Order Topological Phases And Non-Hermitian Phases Protected By Generalized Rotational Symmetry, Kai Chen

Dissertations, Theses, and Capstone Projects

Topological phenomena in condensed matter physics have been investigated intensively in the past decades since the discovery of the integer quantum Hall effect (IQHE). For the IQHE, the energy band can be characterized by its topological invariants (Chern number or TKNN invariant), which relates to the quantized Hall conductance directly. Later, this expression was recognized as the first Chern class of a U(1) principal fiber bundle on a torus, where the fibers and torus correspond respectively to the magnetic Bloch waves and the magnetic Brillouin zone. And then, the discoveries of time-reversal symmetric topological insulators in two and three dimensions …

Engineering Rare-Earth Based Color Centers In Wide Bandgap Semiconductors For Quantum And Nanoscale Applications, Gabriel I. López-Morales

Dissertations, Theses, and Capstone Projects

For many years, atomic point-defects have been readily used to tune the bulk properties of solid-state crystalline materials, for instance, through the inclusion of elemental impurities (doping) during growth, or post-processing treatments such as ion bombardment or high-energy irradiation. Such atomic point-defects introduce local ‘incompatible’ chemical interactions with the periodic atomic arrangement that makes up the crystal, resulting for example in localized electronic states due to dangling bonds or excess of electrons. When present in sufficient concentrations, the defects interact collectively to alter the overall bulk properties of the host material. In the low concentration limit, however, point-defects can serve …

The Interaction Of Different Primary Producers And Physical And Chemical Dynamics Of An Urban Shallow Lake, Majid Sahin

Dissertations, Theses, and Capstone Projects

An artificial urban shallow lake, Prospect Park Lake (PPL), is situated on a terminal moraine in Brooklyn New York, and supplied with municipal water treated with ortho-phosphates. The constant input of the phosphate nutrient is the primary source of eutrophication in the lake. The numerous pools along the water course houses various aquatic phototrophs, which influence the water quality and the state of the system, driving conditions into favoring the survival of their species. In the first half of the dissertation, the focus of the project is on analyzing how the different primary producers in different regions of PPL affect …

Stability Of Two-Dimensional Magnetic Skyrmions, Amel Derras-Chouk

Dissertations, Theses, and Capstone Projects

Magnetic skyrmions are whirls formed by magnetic moments in a crystal. They have attracted attention largely due to their topological protection, which provides an avenue for technology like next-generation memory storage. The idea of topologically protected solutions of a quantum field theory was originally proposed by Tony Skyrme when he developed a model to explain the stability of hadrons in particle physics. His work has extended far beyond his original intent to several areas of condensed matter physics. Here we focus on skyrmions in magnetic materials.

Skyrme's original theory modeled excitations which exist in three spatial dimensions, a requirement for …

Removal Of Anisotropic Background From Neutral Pion And Tagged Direct Photon–Hadron Correlations Of Au+Au 200 Gev Collisions, Zachary Rowan

Dissertations, Theses, and Capstone Projects

A reaction plane dependent event mixing technique is developed to remove the collective background from two particle correlation measurements in heavy ion collisions. The method eliminates the need for any external flow measurements and is well suited for studying the path length dependence of particle production in quark-gluon plasma. Central to mid-central, as well as in vs out-of-plane, per neutral pion trigger integrated away-side hadron yield comparisons are made. Results suggest a significant path length dependent partonic energy loss in the medium. A tagging method is also introduced to measure the direct photon yield for various collision criteria. Direct photon …