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Physics 516: Electromagnetic Phenomena (Spring 2020), Philip C. Nelson 2020 University of Pennsylvania

Physics 516: Electromagnetic Phenomena (Spring 2020), Philip C. Nelson

Department of Physics Papers

These course notes are made publicly available in the hope that they will be useful. All reports of errata will be gratefully received. I will also be glad to hear from anyone who reads them, whether or not you find errors: pcn@upenn.edu.


Design Of Submicron Structured Guided-Mode-Resonance Near-Infrared Polarizer, Marzia Zaman 2020 University of Arkansas, Fayetteville

Design Of Submicron Structured Guided-Mode-Resonance Near-Infrared Polarizer, Marzia Zaman

Theses and Dissertations

The objective of this research is to design a larger submicron linear polarizer in the near-infrared wavelength range with a wide bandwidth which can be fabricated using the conventional thin-film microfabrication technology to reduce cost. For this purpose, a gold (Au) wire-grid transmission-type transverse-magnetic (TM) polarizer and a silicon (Si) wire-grid reflection-type TM polarizer, were designed using the guided-mode-resonance filter. The Au wire-grid TM polarizer of 700nm grating width and 1200nm grating period has 95% transmittance at 2400nm, more than 1000nm resonance peak bandwidth, and an extinction ratio (ER) of around 300 with a moderated level of sidebands. The 700nm ...


Symmetry And Interface Considerations For Interactions On Mos2, Prescott E. Evans 2020 University of Nebraska–Lincoln

Symmetry And Interface Considerations For Interactions On Mos2, Prescott E. Evans

Theses, Dissertations, and Student Research: Department of Physics and Astronomy

The critical role of symmetry, in adsorbate-MoS2 interactions, has been demonstrated through a variety of electronic structure, topology, and catalytic studies of MoS2 and MoS2 composites.A combination of density functional theory and experiment exhibiting diiodobenzene isomer dependent adsorption rates highlight frontier orbital symmetry as key to adsorption on MoS2. It is clear that the geometry and symmetry of MoS2 influences the creation and stability of surface defects, that in turn affect catalytic activity and a myriad of other applications. We have shown that surface reactions such the methanol to methoxy reaction can create defects ...


Fabrication Of Suspended Microbolometers On Soi Wafers, Isaac Maxfield 2020 Utah State University

Fabrication Of Suspended Microbolometers On Soi Wafers, Isaac Maxfield

Physics Capstone Projects

A bolometer is a device to measure radiation energy by converting photon energy into heat on an isolated absorber. We plan to use carbon-nanotube (CNT) based absorber to enhance the photon absorption. The absorber is a few microns in size and is suspended with micron-sized bridges which also support metal lines for electrical measurements.


Synthesis Of Graphene By Liquid Precursors At Lower Temperatures, Clayton Hansen 2020 Utah State University

Synthesis Of Graphene By Liquid Precursors At Lower Temperatures, Clayton Hansen

Physics Capstone Projects

Benzene, toluene, and xylene can be liquid precursors for graphene and carbon nanotube synthesis. However, the growth mechanisms can have greater variances for different carbon allotropes. In the case of graphene, Cu can be the catalyst for dehydrogenation and provides a weakly-coupled substrate for 2-dimensional graphene nucleation and growth. In the case of carbon nanotubes, Fe nanoparticles are essential to catalyze the C-C bonds breaking and dissolve carbon before the precipitation of a graphene cap over the catalyst particle where a tube forms. Controlling the precursor feed rate is crucial for a successful synthesis. In this research, we developed a ...


Waves Over Mcmurdo Station, Robert Johnson 2020 Utah State University

Waves Over Mcmurdo Station, Robert Johnson

Physics Capstone Projects

Atmospheric gravity waves (GWs) are generated by gravity acting on weather systems effectively causing them to oscillate. These waves can then propagate upwards into the upper atmosphere, where they are observed as they pass through glowing layers of gas, called airglow, in the upper atmosphere at approximately 87 kilometers altitude. Using Physics and a little bit of chemistry we can observe the properties of these waves with special infrared cameras. Combining the data between images taken at the same time but with different filters, we can determine the temperature amplitudes of the waves, important for improving our understanding of their ...


Material Outgassing Kinetics: The Development Of A Testing Capability, Alex Kirkman 2020 Utah State University

Material Outgassing Kinetics: The Development Of A Testing Capability, Alex Kirkman

Physics Capstone Projects

Contamination due to outgassing of materials can cause the degradation of critical hardware of a spacecraft. Using outgassing rates, kinetic expressions can be developed and used in models to predict the evolution of molecules and migration of contaminants for specific materials. These models could be used in the selection process of materials to help mitigate the amount of contamination of mission critical hardware for the expected life of the spacecraft. By using the ASTM E1559 test standard this can be achieved. This standard uses the quartz crystal microbalance (QCM) collection approach. A temperature-controlled effusion cell, containing the sample material, impinges ...


On Quantum Effects Of Vector Potentials And Generalizations Of Functional Analysis, Ismael L. Paiva 2020 Chapman University

On Quantum Effects Of Vector Potentials And Generalizations Of Functional Analysis, Ismael L. Paiva

Computational and Data Sciences (PhD) Dissertations

This is a dissertation in two parts. In the first one, the Aharonov-Bohm effect is investigated. It is shown that solenoids (or flux lines) can be seen as barriers for quantum charges. In particular, a charge can be trapped in a sector of a long cavity by two flux lines. Also, grids of flux lines can approximate the force associated with continuous two-dimensional distributions of magnetic fields. More, if it is assumed that the lines can be as close to each other as desirable, it is explained how the classical magnetic force can emerge from the Aharonov-Bohm effect. Continuing, the ...


Measurements Of Fast Alpha Decays In The 100sn Region, Ian Connor Cox 2020 University of Tennessee, Knoxville

Measurements Of Fast Alpha Decays In The 100sn Region, Ian Connor Cox

Chancellor’s Honors Program Projects

No abstract provided.


Integrated Photonic Device, Brittney Kuhn 2020 Chapman University

Integrated Photonic Device, Brittney Kuhn

Student Scholar Symposium Abstracts and Posters

In computer mediated communication networks, information is typically encoded optically to transmit signals over long distances. At a network node, the optical signal is transformed into the electrical domain, processed electronically, and transformed back to an optical state to reach its destination. Transitioning between optical and electrical encoding of the signal is a potential security weak point, especially for quantum communication links. If information can remain in one state as it travels through the network, then security breaches can be detected and dealt with more easily. Furthermore, keeping the information in one state can reduce power consumption in the network ...


Hot Electron Chemistry On Bimetallic Plasmonic Nanoparticles, Bryn E. Merrill, Bingjie Zhang, Jerry LaRue 2020 Chapman University

Hot Electron Chemistry On Bimetallic Plasmonic Nanoparticles, Bryn E. Merrill, Bingjie Zhang, Jerry Larue

Student Scholar Symposium Abstracts and Posters

Catalysis provides pathways for efficient and selective chemical reactions through the lowering of energy barriers for desired products. Gold nanoparticles (AuNP) show excellent promise as plasmonic catalysts. Localized surface plasmon resonances are oscillations of the electron bath at the surface of a nanoparticle that generate energetically intense electric fields and rapidly decay into energetically excited electrons. The excited electrons have the potential to destabilize strongly bound oxygen atoms through occupation of accessible anti-bonding orbitals. Tuning the anti-bonding orbitals to make them accessible for occupancy will be achieved by coating the AuNP in a thin layer of another transition metal, such ...


Computational Simulations Of Temperature-Dependent Dynamics In Type Ii Superconductors Using A Material Specific Formulation Of Ginzburg Landau Theory, Aiden Harbick 2020 William & Mary

Computational Simulations Of Temperature-Dependent Dynamics In Type Ii Superconductors Using A Material Specific Formulation Of Ginzburg Landau Theory, Aiden Harbick

Undergraduate Honors Theses

Superconducting Radio Frequency (SRF) cavities play a fundamental role in particle accelerators. Efficient operation depends on expelling magnetic flux from the cavity, and any residual flux that remains trapped after cooling below the critical temperature can have a significant impact on performance. Experimental evidence suggests that material defects as well as cooling protocols can have a strong impact on subsequent performance. To better understand these phenomena, we use time-dependent Ginzburg-Landau theory implemented as finite-element simulations. We adapt the theory to allow spatial variation of material-specific parameters along with realistic temperature dependencies. We report on numerical experiments for different configurations of ...


Determining The Phase Of The Diurnal, Solar Thermal Tidal Wave In The Upper Atmosphere Using Nighttime Na Lidar Measurements, Trevor Harshman 2020 Utah State University

Determining The Phase Of The Diurnal, Solar Thermal Tidal Wave In The Upper Atmosphere Using Nighttime Na Lidar Measurements, Trevor Harshman

Physics Capstone Projects

Solar thermal tidal waves play a critical role in the dynamics of the mesosphere and thermosphere. Obtaining measurements of the diurnal tidal wave above 100 km is difficult. This could be solved using a physics-based empirical model. To derive this model requires knowing the phase at different points along the tidal wave. In this study, I determine the phase at multiple points along the thermal diurnal tidal wave using measurements taken by a fluorescence lidar in the range of 80 to 100 km. A simple calculation of the phase based on the zeroes and extrema of the wave is demonstrated.


Impact Of Nematicity On The Relationship Between Antiferromagnetic Fluctuations And Superconductivity In Fese0.91s0.09 Under Pressure, Khusboo Rana, Li Xiang, Paul W. Wiecki, Raquel A. Ribeiro, Guilherme Gorgen Lesseux, Anna E. Böhmer, Sergey L. Bud’ko, Paul C. Canfield, Yuji Furukawa 2020 Iowa State University and Ames Laboratory

Impact Of Nematicity On The Relationship Between Antiferromagnetic Fluctuations And Superconductivity In Fese0.91s0.09 Under Pressure, Khusboo Rana, Li Xiang, Paul W. Wiecki, Raquel A. Ribeiro, Guilherme Gorgen Lesseux, Anna E. Böhmer, Sergey L. Bud’Ko, Paul C. Canfield, Yuji Furukawa

Ames Laboratory Accepted Manuscripts

The sulfur-substituted FeSe system, FeSe1−xSx, provides a versatile platform for studying the relationship among nematicity, antiferromagnetism, and superconductivity. Here, by nuclear magnetic resonance (NMR) and resistivity measurements up to 4.73 GPa on FeSe0.91S0.09, we established the pressure- (p-) temperature (T) phase diagram in which the nematic state is suppressed with pressure showing a nematic quantum phase transition (QPT) around p=0.5GPa, two superconductivity (SC) regions separated by the QPT appear, and antiferromagnetic (AFM) phase emerges above ∼3.3GPa. From the NMR results up to 2.1 GPa, AFM fluctuations are revealed to be characterized by ...


Construction Of A Hyperspectral Imager Using 3d-Printed And Off-The-Shelf Components, Joshua Moorhouse 2020 University of Arkansas, Fayetteville

Construction Of A Hyperspectral Imager Using 3d-Printed And Off-The-Shelf Components, Joshua Moorhouse

Mechanical Engineering Undergraduate Honors Theses

The Arkansas Center for Space and Planetary Sciences is working in collaboration with the Mechanical Engineering department to create a relatively cheap and modifiable hyperspectral imager. It is constructed using 3D-printed and off-the-shelf components from Edmund Optics and Amazon. The iteration created in this paper delivers spectrograms in the visible spectrum. The long-term goals of the camera are to create hyperspectral images from these spectrograms and to advance the imager into the infrared and near-infrared spectra. This imager is being developed to be used in the Arkansas Center for Space and Planetary Sciences environmental test chambers to further the scientific ...


Analyzing Flash X-Ray Machine Diagnostics, Sebastian Bustillo, Asaph Camillo, Jake Morris 2020 Ouachita Baptist University

Analyzing Flash X-Ray Machine Diagnostics, Sebastian Bustillo, Asaph Camillo, Jake Morris

Scholars Day Conference

The Cygnus Dual Beam Radiographic Facility consists of two flash x-ray machines, Cygnus 1 and 2. The seamless performance of these machines is critical to the maintenance of the United States stockpile of nuclear weapons. Since these SubCritical experiments cost about $104 million when something malfunctions millions of dollars are lost. As a result, it is imperative to assess the performance of the machine from diagnostics collected by the different sensors. Its performance is measured by the level of radiation dose a shot obtains. Utilizing exploratory data analysis, interesting trends were found and a 74.1% level of correctness was ...


Studying And Correcting For Helicity-Correlated False Asymmetries In The Prex Ii And Crex Experiments, Carrington Metts 2020 William & Mary

Studying And Correcting For Helicity-Correlated False Asymmetries In The Prex Ii And Crex Experiments, Carrington Metts

Undergraduate Honors Theses

The goal of the PREx II and CREx experiments are to determine the size of the neutron distribution in 208Pb and 48Ca, respectively. Because these isotopes have a large discrepancy in between the number of neutrons and protons, theoretical models predict that some of the neutrons will arrange themselves in a “skin” on the nucleus’s surface. Prior results from the PREx I experiment confirmed the existence of the neutron skin in 208Pb. All of the mentioned experiments employ the technique of parity-violating electron scattering. Electron-nucleus weak interactions are dominated by electron-neutron scattering, which is an order ...


Conservation Of Orbital Angular Momentum In Degenerate Four-Wave Mixing Via Rubidium Vapor, Kangning Yang 2020 William & Mary

Conservation Of Orbital Angular Momentum In Degenerate Four-Wave Mixing Via Rubidium Vapor, Kangning Yang

Undergraduate Honors Theses

We present an experimental platform which can generate quantum-correlated beams with Orbital Angular Momentum (OAM) via degenerate Four-Wave Mixing (FWM) in Rubidium vapor. We further investigated the conservation of OAM before and after FWM by performing LG mode decomposition using interferometer. To compare our experimental result with theoretical prediction, we simulated a simplified version of our set up. Moreover, we used this toy model to study the conservation of radial and angular intensity profile through changing parameters limited by our set up. In general, we found that FWM preserves most information consisted in OAM, but has a rather loose control ...


Four-Wave Mixing With Orbital Angular Momentum Transfer, Hana Warner 2020 William & Mary

Four-Wave Mixing With Orbital Angular Momentum Transfer, Hana Warner

Undergraduate Honors Theses

We explore the conservation of orbital angular momentum (OAM) in the four-wave mixing (FWM) process in hot rubidium vapor. Since most modern communication systems send data in pulses corresponding to bits, we can use OAM to encode more information in each pulse by assigning structure to each signal. Furthermore, because FWM can be used to generate entangled photon pairs, we can use this process to bring enhanced signal security. We experimentally studied FWM with a wide range of Laguerre-Gaussian modes and their superpositions and observed OAM transfer from the probe field to a generated Stokes field. By studying the output ...


Gait Characterization Using Computer Vision Video Analysis, Martha T. Gizaw 2020 College of William and Mary

Gait Characterization Using Computer Vision Video Analysis, Martha T. Gizaw

Undergraduate Honors Theses

The World Health Organization reports that falls are the second-leading cause of accidental death among senior adults around the world. Currently, a research team at William & Mary’s Department of Kinesiology & Health Sciences attempts to recognize and correct aging-related factors that can result in falling. To meet this goal, the members of that team videotape walking tests to examine individual gait parameters of older subjects. However, they undergo a slow, laborious process of analyzing video frame by video frame to obtain such parameters. This project uses computer vision software to reconstruct walking models from residents of an independent living retirement ...


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