Engineering Physics Commons^™

Corrigendum: Surface Termination And Schottky-Barrier Formation Of In4Se3(001) [Semiconductor Science And Technology (2020) 35 (065009) Doi: 10.1088/1361-6641/Ab7e45], Archit Dhingra, Pavlo V. Galiy, Lu Wang, Nataliia S. Vorobeva, Alexey Lipatov, Angel Torres, Taras M. Nenchuk, Simeon J. Gilbert, Alexander Sinitskii, Andrew J. Yost, Wai-Ning Mei, Keisuke Fukutani, Jia Shiang Chen, Peter Dowben

Peter Dowben Publications

Through the description of various surface terminations, the chain direction of In4Se3 in this paper [1] is implied to be in the plane of its surface. Even though the common convention for photoemission spectroscopy is to place z-axis along the surface normal, the axis perpendicular to the growth direction for this indium selenide is the crystallographic a-axis (and not the c-axis) [2–4]. Therefore, in our work the surface of In4Se3 should have been labeled (100), and not (001), to prevent any confusion that may have resulted from a less than conventional index notation. Data availability statement The data that support …

Colossal Intrinsic Exchange Bias From Interfacial Reconstruction In Epitaxial Cofe2 O4/Al2 O3 Thin Films, Detian Yang, Yu Yun, Arjun Subedi, Nicholas E. Rogers, David M. Cornelison, Peter Dowben, Xiaoshan Xu

Peter Dowben Publications

We have studied the epitaxial CoFe₂O₄ (111) films grown on Al₂O₃ (0001) substrates of different thickness at various temperature and discovered colossal intrinsic exchange bias up to 7 ± 2 kOe. X-ray and electron diffraction clearly indicate an interfacial layer about 2 nm of different crystal structure from the “bulk” part of the CoFe₂O₄ film. The thickness dependence of the exchange bias suggests a hidden antiferromagnetic composition in the interfacial layer that couples to the ferrimagnetic “bulk” part of the CoFe₂O₄ film as the origin of the exchange …

Design And Characterization Of Standard Cell Library Using Finfets, Phanindra Datta Sadhu

Master's Theses

The processors and digital circuits designed today contain billions of transistors on a small piece of silicon. As devices are becoming smaller, slimmer, faster, and more efficient, the transistors also have to keep up with the demands and needs of the daily user. Unfortunately, the CMOS technology has reached its limit and cannot be used to scale down due to the transistor's breakdown caused by short channel effects. An alternative solution to this is the FinFET transistor technology, where the gate of the transistor is a three dimensional fin that surrounds the transistor and prevents the breakdown caused by scaling …

Realization Of Bsu First Magneto-Optical Trap For The Spatial Confinement Of Rb Atoms Using Next Generation Fiber Optic Capabilities With Minimot, Brahmin Thurber-Carbone

Honors Program Theses and Projects

This paper will be a combination of my theoretical and experimental work toward Bridgewater State Universities first Magneto-Optical Trap (MOT) for laser cooling and trapping of neutral atoms in order to study fundamental quantum mechanical behavior of Rubidium (Rb) atoms. The goal of the theoretical aspect is to complete details of well-established works on how the complicated quantum, atomic, and electromagnetic (laser) interactions required to understand the design and operation of the MOT reduce to the physics and mathematics of a damped oscillator. This is made explicitly clear using familiar damped oscillator systems, such as a spring/mass/damping or pendulum/mass/damping (ie …

Magnetism And Topological Hall Effect In Antiferromagnetic Ru2Mnsn-Based Heusler Compounds, Wenyong Zhang, Balamurugan Balasubramanian, Yang Sun, Ahsan Ullah, Ralph Skomski, Rabindra Pahari, Shah R. Valloppilly, Xingzhong Li, Cai-Zhuang Wang, Kai-Ming Ho, David J. Sellmyer

Nebraska Center for Materials and Nanoscience: Faculty Publications

Heusler compounds and alloys based on them are of great recent interest because they exhibit a wide variety of spin structures, magnetic properties, and electron-transport phenomena. Their properties are tunable by alloying and we have investigated L2₁-ordered compound Ru₂MnSn and its alloys by varying the atomic Mn:Sn composition. While antiferromagnetic ordering with a Néel temperature of 361 K was observed in Ru₂MnSn, the Mn-poor Ru₂Mn_0.8Sn_1.2 alloy exhibits properties of a diluted antiferromagnet in which there are localized regions of uncompensated Mn spins. Furthermore, a noncoplanar spin structure, evident from …

Virtual Prototyping Of Liquid Lithium Divertor Concepts, Brennan Arnold

Macalester Journal of Physics and Astronomy

A tokamak divertor must withstand power deposition in excess of 10 MW/m^2 in steady state and much higher in disruptions, enough to destroy nearly any material. In order to handle this extreme heat, there is some interest in using liquid metal flows to continually renew the divertor surface. In this paper, we examine an idea for a divertor with a porous surface that allows liquid lithium flowing through the divertor to percolate to the plasma facing surface. This idea is complicated by magnetohydrodynamic drag, where the stong magnetic fields in the tokamak cause the lithium to flow too slowly to …

Radiosonde High Altitude Measurements Of Radiation Levels And Cosmic Ray Events, Ayodeji Opeyemi Akinuliola

Electronic Theses and Dissertations

Just above us, cosmic rays are hurtling in from space. These fast moving particles crash uncontrollably into molecules in the atmosphere, causing spontaneous decays of these particles. Despite the fact that we are broadly shielded from this radiation on earth, these particles can still disturb humans and electronics alike. Therefore, this research focuses on expanding the use of long-range radio transmitters such as radiosondes to transmit valuable data such as cosmic ray flux, geographical position, atmospheric temperature, pressure, etc. This can improve real-time radiation monitoring for aviation industry crew and passengers working in potentially higher radiation environments. On March 11, …

Structural Origin Of Thermal, Mechanical Properties And Morphological Behaviors Of Semiconducting Polymers, Song Zhang

Dissertations

The past decades have witnessed a surging exploration of semiconducting polymers for the application of wearable and flexible organic electronic devices. Despite the increased amounts of molecular engineered polymers and their much-improved electrical performances, a systematic study of the structure-thermal/mechanical property-morphology relationship of semiconducting polymers is still less investigated.

To understand the thin-film mechanical properties, a pseudo-free standing tensile tester was self-built and utilized to obtain their real-time stress-strain behaviors through uniaxial stretching on top of the water surface. It also enables the first quantitative measurement of fracture energy on ultrathin polymeric films. Through multiple mechanical testing methods (i.e., strain-rate …

Voltage-Controlled Magnetic Anisotropy In Antiferromagnetic Mgo-Capped Mnpt Films, P. H. Chang, Wuzhang Fang, T. Ozaki, Kirill Belashchenko

Kirill Belashchenko Publications

The magnetic anisotropy in MgO-capped MnPt films and its voltage control are studied using first-principles calculations. Sharp variation of the magnetic anisotropy with film thickness, especially in the Pt-terminated film, suggests that it may be widely tuned by adjusting the film thickness. In thick films the linear voltage control coefficient is as large as 1.5 and -0.6 pJ/Vm for Pt-terminated and Mn-terminated interfaces, respectively. The combination of a widely tunable magnetic anisotropy energy and a large voltage-control coefficient suggest that MgO-capped MnPt films can serve as a versatile platform for magnetic memory and antiferromagnonic applications.

Direct Drive Solar Panel Control Circuit, Marcorios Bekheit

Physics

A control circuit is built for insulated solar electric cookers (ISEC). Power delivery and temperature safety are the focus. Using a maximum power point tracking (MPPT) algorithm, Arduino Nano, voltage and current sensors, and a buck converter, the solar panel’s output power was maximized for a direct load heat resistor with 3.5Ω for a range of solar intensities. Using a resistance temperature detector, a temperature sensor is built for safety shutoff.

Memory Module Design For High-Temperature Applications In Sic Cmos Technology, Affan Abbasi

Graduate Theses and Dissertations

The wide bandgap (WBG) characteristics of SiC play a significant and disruptive role in the power electronics industry. The same characteristics make this material a viable choice for high-temperature electronics systems. Leveraging the high-temperature capability of SiC is crucial to automotive, space exploration, aerospace, deep well drilling, and gas turbines. A significant issue with the high-temperature operation is the exponential increase in leakage current. The lower intrinsic carrier concentration of SiC (10-9 cm-3) compared to Si (1010 cm-3) leads to lower leakage over temperature. Several researchers have demonstrated analog and digital circuits designed in SiC. However, a memory module is …

Mechanical Behavior Of Cyclo-18 On Nickel And Copper Substrates, Reagan Michael Kraft

Mechanical Engineering Undergraduate Honors Theses

Carbyne, an -hybridized allotrope of carbon, has been the subject of many studies recently due to its incredible mechanical properties and small size. More recently, another -hybridized allotrope known as cyclo-18, has gained interest. In this study, computational molecular dynamics will be used to determine the mechanical properties of cyclo-18. Peeling and shearing tests of the molecule will be conducted on nickel and copper, which are respectively active and less-active transition metals. Additionally, a carbyne chain of equal length will undergo the same tests on the copper substrate to compare the mechanical properties of the two. The results conclude that …

Designing Cryogenic Strain Device For 2d Materials, Jake Carter

Mechanical Engineering Undergraduate Honors Theses

The Churchill lab working within the Physics Department at the University of Arkansas is working to create important quantum states including weak topological insulators (TIs) through the use of symmetry engineering and topological electronic states in two-dimensional (2D) crystals of WHM materials. Experimental results of these topological states have been obstructed due to the difficulty to perform controlled in situ strain. This project strives to create a mount to utilize a piezoelectric nanopositioner within cryostats achieving an in situ strain that creates the quantum states the lab is looking to observe. This report also examines the necessary equations to determine …

Simulation Of Optical Properties Of Dielectric Layers From Visible To Near Infrared Spectral Range, Andrew Cochran, Cory Conkel

ONU Student Research Colloquium

Optical properties of dielectrics play a critical role in various applications including the design and manufacture of optical components & devices such as detectors, filters, imagers, lenses, optical coatings, photonic crystals, sensors and waveguides, and solar cells. Radiative properties of varying thicknesses of different dielectrics such as Aluminum Oxide (Al2O3), Silicon Dioxide (SiO2), Indium Tin Oxide (ITO), Magnesium Fluoride (MgF2) and Silicon Nitride (Si3N4) have been simulated and compared in the range of visible to near infrared by mathematical modelling using MATLAB simulations. The results of the evolution of the radiative properties, as a function of dielectric material thickness, on …

E. Coli And Total Coliform, Emilio Wilson

Undergraduate Research Competition

Water is important because we use it for our everyday use, whether it's for drinking, bathing, or for our enjoyment. Pollution causes the environment to have a harmful effect, which is usually caused by microorganisms (bacteria) Some of those Bacteria include E. coli and Total Coliform. They're mainly found in the intestines of humans, in animals, in water, and also found in the soil. Most of these bacteria are harmless but it can provide you with symptoms of diarrhea, vomiting, and stomach cramps. When water comes in contact with feces, humans, or any living organism, the water is contaminated. There …

Water Monitoring At Ccu (Conductivity, Ph, Do), Gage Campbell

Undergraduate Research Competition

Monitoring water quality is important for human health. This study focuses on the 544 West site and the parameters conductivity, pH, and dissolved oxygen (DO). Data used is from Oct. 2011 through Nov. 2020 on the Coastal Carolina University campus and used an Orion™ A329 multimeter. 741 samples were collected for Conductivity, with an average of 407.8 uS/cm (145.8 uS/cm - 690.7 uS/cm). 738 samples were collected for pH, with an average of 7.15 (6.09 - 8.11). All data fell within the SC DHEC water quality standard of pH which is no lower than 5.0 or above 8.5. 735 samples …

Detecting Radium-226 In Submarine Groundwater Discharge, Rashaun Davis

Undergraduate Research Competition

Studies have been done to see if abundance of neutrinos have an effect on the decay rate of radioactive nuclei. Questions regarding the proximity of the sun and the concentration of the flux of neutrinos as a result, have emerged due to there being more counts in the winter when the sun is closer versus there being less counts in the summer when the sun is farther away. Other studies say that the cause of the difference in counts are more local, as in the environmental conditions like temperature and various background radiation that interferes with the counts of the …

Design Of Smart Trashcan, Haoran Song

Senior Theses

A smart trashcan has been designed which can bring convenience to people for throwing their garbage away during the COVID-19 pandemic. A prototype is made from cardboard to demonstrate its function. This trashcan can sense people who are coming and leaving, and it can open and close automatically. The trashcan is powered by solar energy. A solar panel is mounted on top of the trashcan supporter. This design is specifically for use in China.

Deathtrap, Blake Traylor

Vázquez-Valarezo Poetry Award

I could have titled this one "Bad Trip in an Elevator," but that would twist the poem away from its authenticity. You'll have to trust me on this one: this happened. Not in the usual sense, but in that fiction-is-truth-in-a-funhouse-mirror, postmodern Tim O'Brien sense. And hallucinogens were not involved, nor are they encouraged or condoned. (Do with that Wretched Passive Voice what you will.)

If the word "Deathtrap" didn't amuse me so much, I really could have run with the title "Tired." Or maybe "Very Tired" would have been better. And then there are always the big-hitters: "Fatigue," "Exhaustion," "Are …

Investigation Of Trajectory And Control Designs For A Solar Sail To The Moon, Michelle Nadeau

Doctoral Dissertations and Master's Theses

NASA’s Artemis program and other government and commercial projects are working toward establishing a sustainable human presence on the moon. This thesis investigates the technical feasibility of a solar sail-based spacecraft (sailcraft) as a low-cost method of delivering cargo or science instruments to the moon and demonstrates how this sailcraft could be controlled to change its orbit. The concept is a low-cost, commercial launch vehicle-deployable, CubeSat-based sailcraft with a square sail, assumed attitude control, and a small payload traversing from low-Earth orbit toward the moon with zero propellant use. In this thesis, methods for sailcraft to increase altitude, the trajectory …