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Investigation Of Cooperative Subradiance In Dense Ultracold Rubidium Ensembles, Brent Michael Jones

Physics Theses & Dissertations

This dissertation presents results of an experimental investigation of the time resolved fluorescence from a cold and dense ensemble of ⁸⁷Rb atoms after the sample is illuminated by a short probe pulse. The goal of the experiment was to investigate cooperative subradiant behavior, characterized by a much longer decay time compared to the natural lifetime, induced in an off resonant probe regime. Such long lived states, if controllable, would provide a means to store quantum information. The samples were initially created in a magnetooptical trap before atoms were loaded into a far off resonance trap to achieve atomic densities …

Problem-Based Learning Model Assisted With A Humanistic-Merdeka Belajar Approach Improved Biology Students’ Learning Ownership, Dita Tri Mulyani, Dwi Listyorini

Jurnal Pendidikan Sains

Fostering ownership over learning constitutes a pivotal aspect for students to cultivate a comprehensive understanding, employ cognitive strategies effectively, hone essential skills, and refine learning methodologies. Preliminary studies have underscored a prevalent deficiency in the learning ownership among biology students, categorizing it as notably low. The purpose of this study is to ascertain the effect of the Project Based Learning (PBL) model assisted with a Humanistic-Merdeka Belajar (HMB) approach, in nurturing students’ ownership of their learning endeavors. Employing a quasi-experimental design, the research adopts a pre-test post-test non-equivalent control group configuration, administered both prior to and following the intervention within …

Students’ Science Literacy On Discussion-Based Contextual Approaches Of Human Reproductive System Learning, Yeni Mulyaningsih, Chaerul Rochman, Adam Malik, Tri Wahyu Agustina, Yulia Sukmawardani, Nur Hamidah, Nurul Annisa

Jurnal Pendidikan Sains

The aim of this study was to enhance students’ science literacy through a discussion-based contextual approach in the learning of the human reproductive system. This quantitative research employed an experimental method with a quasi-experimental posttest-only design. The study involved 60 students, with 30 students each in class XI MIPA 4 serving as the experimental group and class XI MIPA 5 serving as the control group. The control group received instruction through a conceptual approach-based lecture method, whereas the experimental group engaged in learning through a contextual approach-based discussion method. The research instrument comprised 10 open-ended science literacy questions pertaining to …

Identify Resources Activated By Students When Solving Straight Motion Kinematics Problems With Different Representation, Nur Utami Amaliah, Sutopo Sutopo, Eny Latifah, Hutkemri Zulnaidi

Jurnal Pendidikan Sains

This research aims to explore kinematic resources in linear kinematics by utilizing different forms of problem representation. The study was conducted by administering 15 reasoned multiple-choice questions to 146 high school students from three districts in Central Sulawesi, Indonesia. The research instrument covers topics in linear kinematics, including distance, displacement, speed, and velocity, presented through diagrammatic representations, graphs, and mathematical equations. The students’ written answers were analyzed both quantitatively and qualitatively. Quantitative analysis was conducted to determine descriptive statistics from the data, while qualitative analysis identified the resources students activated when solving these questions. The findings reveal that the various …

Lunar: Automated Input Generation And Analysis For Reactive Lammps Simulations, Josh Kemppainen, Jacob R. Gissinger, S. Gowtham, Gregory Odegard

Michigan Tech Publications

Generating simulation-ready molecular models for the LAMMPS molecular dynamics (MD) simulation software package is a difficult task and impedes the more widespread and efficient use of MD in materials design and development. Fixed-bond force fields generally require manual assignment of atom types, bonded interactions, charges, and simulation domain sizes. A new LAMMPS pre- and postprocessing toolkit (LUNAR) is presented that efficiently builds molecular systems for LAMMPS. LUNAR automatically assigns atom types, generates bonded interactions, assigns charges, and provides initial configuration methods to generate large molecular systems. LUNAR can also incorporate chemical reactivity into simulations by facilitating the use of the …

Thermal Stability Of Amorphous Metal Oxides: The Interplay Of Secondary Cations, Degree Of Substitution, And Local Structure, Li Zeng, D. Bruce Buchholz, Denis T. Keane, Tobin J. Marks, Julia E. Medvedeva, Michael J. Bedzyk

Physics Faculty Research & Creative Works

Indium-based amorphous metal oxides (AMOs) are important materials that enable a wide range of electronic and optoelectronic applications. The metal cations that substitute for In are known to effectively tune the material properties as well as to retain the desirable amorphous state when subjected to high operating temperatures. While much attention focuses on property tuning, there is less focus on those fundamental factors that enhance thermal stability. Hence, in this paper, we employ in situ X-ray scattering and ab initio molecular dynamics (MD) to systematically study the effects of secondary cations on the crystallization process. A series of amorphous (In …

Optical Modeling Of Systematic Uncertainties In Detector Polarization Angles For The Atacama Cosmology Telescope, Colin C. Murphy, Steve K. Choi, Rahul Datta, Mark J. Devlin, Matthew Hasselfield, Brian J. Koopman, Jeff Mcmahon, Sigurd Naess, Michael D. Niemack, Lyman A. Page, Suzanne T. Staggs, Robert J. Thornton, Edward J. Wollack

Physics & Engineering Faculty Publications

We present an estimate of the Atacama Cosmology Telescope (ACT) detector polarization angle systematic uncertainty from optics perturbation analysis using polarization-sensitive ray tracing in CODE V optical design software. Uncertainties in polarization angle calibration in CMB measurements can limit constraints on cosmic birefringence and other cosmological parameters sensitive to polarization leakage. Our framework estimates the angle calibration systematic uncertainties from possible displacements in lens positions and orientations, and anti-reflection coating (ARC) thicknesses and refractive indices. With millimeter displacements in lens positions and percent-level perturbations in ARC thicknesses and indices from design, we find the total systematic uncertainty for three ACT …

Defect-Free Nanowelding Of Bilayer Snse Nanoplates, Jing-Rong Ji, John W. D. Villanova, Salvador Barraza-Lopez, Stuart S. P. Parkin, Kai Chang

Physics Faculty Publications and Presentations

Nanowelding is a bottom-up technique to create custom-designed nanostructures and devices beyond the precision of lithographic methods. Here, a new technique is reported based on anisotropic lubricity at the van der Waals interface between monolayer and bilayer SnSe nanoplates and a graphene substrate to achieve precise control of the crystal orientation and the interface during the welding process. As-grown SnSe monolayer and bilayer nanoplates are commensurate with graphene's armchair direction but lack commensuration along graphene's zigzag direction, resulting in a reduced friction along that direction and a rail-like, 1D movement that permits joining nanoplates with high precision. This way, molecular …

An Analysis Of (Hu)Manid Using The Usf Donated Skeletal Collection: Estimating Sex And Ancestry For Edentulous Individuals, Natalie S. Wise

USF Tampa Graduate Theses and Dissertations

The Human Mandible Identification program, (hu)MANid©, enables anthropologists to estimate the sex and ancestry of unidentified skeletal remains from metric and morphoscopic variables from the mandible. The program is suitable for a variety of anthropological contexts, including forensic casework and bioarchaeological or paleoanthropological analyses. The purpose of this research project is to test the accuracy and applicability of the (hu)MANid program on edentulous mandibles. While the authors of (hu)MANid warn against data collection for edentulous mandibles, there are many circumstances in applied forensic casework where the unidentified person is edentulous. Edentulous individuals experience alveolar resorption, which is the loss of …

Effects Of Differing Radiation Methods On Charge Transport In Polymers, Zachary Gibson, Jr Dennison, Virginie Griseri

Presentations

The mitigation of deleterious arcing and sparking onboard spacecraft depends upon a thorough understanding of the electrical properties of the materials involved. This includes not only understanding steady-state parameters such as dark conductivity, but responses to the space environment as well. For example, radiation-induced conductivity drastically changes the conductivity of a material due to the presence of radiation. However, this change in conductivity diminishes away once the radiation is no longer present. There may also be permanent changes, or aging, in the material properties. The physical processes of aging can be complicated and are often difficult to model. Therefore, empirical …

Thermal Effects On The Voc-Sensitive Polydimethylsiloxane Holographic Gratings, Aleksandra Hernik, Faolan Radford Mcgovern, Patrick Iftime, Izabela Naydenova

Conference Papers

The imperative for monitoring volatile organic compounds (VOCs) emerges from their harmful impact on human health when inhaled excessively over a long term. Polydimethylsiloxane (PDMS), valued for its transparency and excellent flexibility, has already been demonstrated as a promising biocompatible and cost-effective transducer for optical VOCs sensing. Moreover, it facilitates further functionalisation with adsorbing materials to enhance sensitivity and selectivity for specific VOCs detection. We fabricated and examined PDMS-based surface diffraction gratings after exposure to selected VOCs, demonstrating different response for polar and non-polar molecules. Investigated gratings were prepared by replicating sinusoidal surface relief structures inscribed in acrylamide photopolymer using …

Photopolymer Material Durability And Safety In Holographic Diffusers For Visual Applications, Matthew Hellis, Alan Casey, Edoardo Splendi, Suzanne Martin, Matthew Sheehan, Kevin Murphy

Articles

This study introduces novel holographic diffuser applications employing acrylamide- or diacetone acrylamide-based photopolymers, patterned within the volume on a micron scale by a single-beam holographic recording process. These diffusers have previously been presented as potential treatments for amblyopia and diplopia. This work has now been extended to spectrometric analysis to determine their properties under broadband light. Diffusive elements with higher diffusion efficiencies exhibited a marginal reduction (< 5%) in diffusion efficiency across most of the visible spectrum. Given the intended application of these holographic diffusers, cytotoxicity assessments were also performed. This is significant as there is a difference in toxicity between the crystalline acrylamide (classified as a category 3 material) and diacetone acrylamide (classified as a category 4 material). The findings indicated substantially lower toxicity in holograms produced with diacetone acrylamide-based photopolymer. The accelerated ageing of both formulations of holographic diffusers indicated that the acrylamide-based holographic diffusers did not reduce efficacy in the 292 days of ageing. The diacetone acrylamide-based holographic diffusers exhibited reduced efficacy by day 182. Despite this, both formulations have been shown to perform for prolonged periods as the treatment modality would require. These results emphasise that holographic diffusers exhibit minimal spectral impact, and longevity on the scale of treatment regimes which are crucial considerations for their prospective use case as treatments for amblyopia and diplopia.

Thz Radar Observations Of Hydrometeors In A Spray Chamber, Zeen Zhu, Fan Yang, Edward Luke, Elise Rosky, Katia Lamer, Pavlos Kollias

Michigan Tech Publications

A THz radar, with its wide bandwidth, is capable of high-resolution imaging down to the centimeter scale. In this study, a THz radar is applied to detect hydrometeors generated in a spray chamber. The observed backscattering signals show fluctuations at centimeter scales, indicating various hydrometeor distribution patterns along the radar beam. A co-located High-Speed Imaging (HSI) sensor is used to measure the Drop Size Distributions (DSD) in the spray chamber. The radar sampling beam is well aligned with the HSI probes, allowing an objective comparison between the remote sensing and in situ observations. In this study, the observed radar power …

Bridging The Geometric And Quantum Information Of Structured Light, Andrew Alexander Voitiv

Electronic Theses and Dissertations

In this Dissertation, we review the several advances we have developed for preparing and measuring the geometric and quantum information of structured light. The geometric phase acts as a memory of transformations undertaken by physical processes; quantum entanglement underpins quantum information science which explores the theoretical and technological applications of nonclassical correlations. Beginning with classical light, we demonstrate novel experiments and measurements of geometric phase that are enabled by spatially structuring laser beams. We then extend those concepts to complement the richer possibilities within quantum optics. Our work covers new abilities in tailoring and measuring the phase content of spatially-structured …

Spin And Charge Transport In Metallic Ferrimagnets And Disordered Magnetic Oxides, Leopoldo A. Hernandez

Electronic Theses and Dissertations

Recent efforts have been exploring the use of thin film synthetic ferrimagnets and disordered magnetic oxides for applications in spintronic devices. Due to the antiferromagnetic exchange interaction, ferrimagnetic materials offer the ultrafast dynamics of the antiferromagnetic exchange, with a net magnetization that can be influenced externally. With two, or more, competing ferromagnet sublattices, interesting properties arise that depend on the final magnetic landscape after growth of the material and it’s inherent magnetic anisotropy energies. Properties such as magnetic compensation temperatures, and perpendicular magnetic anisotropy are attractive for applications in spintronic memory and logic devices, some already being implemented in MRAM …

Differential Elliptic Flow Analysis Of Hadrons With Different Wuark Content In Simulated Pp Collisions, Elhussein Osama

Theses and Dissertations

According to current physics theories, it is assumed that in the first microsecond after the big bang, the universe was in a state of matter called Quark-Gluon Plasma (QGP), where the fundamental consistent of matters (quarks and leptons), were highly energetic, and floating around freely. Searching for such phase of matter; as the possible earliest signatures after the big bang, and among many other interesting experimental measurements, the jet quenching and elliptic flow are the most important ones, in the heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC) experiments.

The azimuthal anisotropy …

Crystallographic Analysis Of The Dorsal Spine Of Squalus Suckleyi, John V. Karavitis

College of Science and Health Theses and Dissertations

The dorsal spine of the spiny dogfish, Squalus acanthias, has been used for age determination of individual specimens since the 1930s. Scientific literature regarding the dorsal spine has to date always referred to it as having an enamel exterior, with a dentin interior surrounding a central pulp cavity. This is similar to the structure observed in a human tooth.

The dorsal spine is composed of cartilage-based tissue that contains bioapatite. Bioapatite is a mixture of hydroxyapatite, Ca₁₀(PO₄)₆(OH)₂ (a calcium salt of phosphoric acid), and other biological material, e.g. calcium carbonate, CaCO_{3 …}

Fundamental Mechanisms Of Energy Exchanges In Autonomous Measurements Based On Dispersive Qubit-Light Interaction, Nicolò Piccione, Maria Maffei, Xiayu Linpeng, Andrew N. Jordan, Kater W. Murch, Alexia Auffèves

Mathematics, Physics, and Computer Science Faculty Articles and Research

Measuring an observable which does not commute with the Hamiltonian of a quantum system usually modifies the mean energy of this system. In an autonomous measurement scheme, coupling the system to a quantum meter, the system's energy change must be compensated by the meter's energy change. Here, we theoretically study such an autonomous meter-system dynamics: a qubit interacting dispersively with a light pulse propagating in a one-dimensional waveguide. The phase of the light pulse is shifted, conditioned to the qubit's state along the 𝑧 direction, while the orientation of the qubit Hamiltonian is arbitrary. As the interaction is dispersive, photon …

Axion Dark Matter With Not Quite Black Hole Domination, Ufuk Aydemi̇r

Turkish Journal of Physics

No abstract provided.

Weyl Tensor Decomposition To The Formation Of Black Hole, Gauree Shanker, Zakia Issa Ndidi

Turkish Journal of Physics

No abstract provided.

Comparative Study Of Α-Α Interaction Potentials Constructed Using Various Phenomenological Models, Ayushi Awasthi, O S K S Sastri

Turkish Journal of Physics

No abstract provided.

Modified Toulmin's Argumentation Model Based On Prior Experiences, Ali Hadi Hasan, Mohamad Ab. Saleh, Ahmed T. Sadiq

Karbala International Journal of Modern Science

Our work focuses on the usefulness of previously stored correct extracted results, which form a sort of stored knowledge got from previous experiences, from enhancing Toulmin's argument model that deals with drug conflict problems in therapeutic diagnostics. New patients are entered using friendly user interface to store in files and then they are matched with the records of previous results, patients’ symptoms and histories datasets which also contain the correct best drugs extracted results. If the new entered record of a patient is matching with any previous record then the correct result of drug will be found immediately and displayed. …

A Novel Method May Reveal Bulk Metallic Glass Compressive Ductility Trends In High Data Rate Nanoindentation, Jordan J. Sickle, Wesley H. Higgins, Wendelin Wright, George M. Pharr, Karin A. Dahmen

Faculty Journal Articles

Recent methods allow novel amorphous alloy compositions to be rapidly manufactured at small scale; however, obtaining materials properties such as compressive ductility from these smaller specimens has remained a challenge. Here, we suggest a potential high-throughput nanoindentation method that may be able to rapidly characterize the relative compressive ductility between these alloys based on their serration characteristics. The properties of emergent serrations, when interpreted in a simple micromechanical stress relaxation model, may order these materials by their compressive plastic strain to failure. These results are consistent with the ordering obtained from compressed specimens as well as with model simulations, suggesting …

Single-Molecule Orientation Imaging Reveals The Nano-Architecture Of Amyloid Fibrils Undergoing Growth And Decay, Brian Sun, Tianben Ding, Weiyan Zhou, Tara S. Porter, Matthew D. Lew

Electrical & Systems Engineering Publications and Presentations

Amyloid-beta (Aβ42) aggregates are characteristic Alzheimer’s disease signatures, but probing how their nanoscale architectures influence their growth and decay remains challenging using current technologies. Here, we apply time-lapse single-molecule orientation-localization microscopy (SMOLM) to measure the orientations and rotational “wobble” of Nile blue (NB) molecules transiently binding to Aβ42 fibrils. We correlate fibril architectures measured by SMOLM with their growth and decay over the course of 5 to 20 min visualized by single-molecule localization microscopy (SMLM). We discover that stable Aβ42 fibrils tend to be well-ordered and signified by well-aligned NB orientations and small wobble. SMOLM also shows that increasing order …

Assigning The Ch Stretch Overtone Spectrum Of Benzene And Naphthalene With Extension To Anthracene And Tetracene Using 2- And 3-Quanta Anharmonic Quantum Chemical Computations, Vincent J. Esposito, Ryan C. Fortenberry, Christiaan Boersma, Louis J. Allamandola

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The CH stretch overtone region (5750–6300 cm⁻¹) of benzene and naphthalene is assigned herein using anharmonic quantum chemical computations, and the trend of how this extends to larger polycyclic aromatic hydrocarbons (PAHs) is established. The assignment of all experimental bands to specific vibrational states is performed for the first time. Resonance polyads and the inclusion of 3-quanta vibrational states are both needed to compute accurate vibrational frequencies with the proper density-of-states to match the experimental band shape. Hundreds of 3-quanta states produce the observed band structure in naphthalene, anthracene, and tetracene, and this number is expected to increase …

Einstein Field Equations And The Solutions For Uncharged Black Holes, Yogesh Mahat

Masters Theses

The General Theory of Relativity, formulated by the brilliant mind of Albert Einstein, stands as one of the most fundamental and revolutionary pillars of modern physics. This elegant theory of gravity not only offers a comprehensive explanation of the workings of the universe on a large scale, but it has also paved the way for groundbreaking advancements in the field of mathematics. This thesis begins by providing a concise overview of the key mathematical principles that are crucial to understanding Einstein’s theory. These principles form the basis for deriving the field equations that Einstein introduced. From there, these equations are …

Development And Application Of Magnus Expansion Based Propagators For Problems In Spectroscopy And Quantum Dynamics, Taner M. Ture

Dissertations, Theses, and Capstone Projects

Stable and accurate numerical propagators of time-evolution equations in quantum mechanics are required to capture correct dynamical behavior, especially in the long time limit. Magnus expansion (ME) provides a general way to expand the real time propagator of a time dependent Hamiltonian within the exponential such that the unitarity is satisfied at any order. Integrators are developed by truncating the ME and using explicit integration of Lagrange interpolation formulas for the time dependent Hamiltonian within each time interval. The derived approximations are studied in a numerical test and compared to other available expressions. The sixth order expression is applied to …

Aspects Of Parity Breaking In Classical And Quantum Fluids, Dylan J. Reynolds

Dissertations, Theses, and Capstone Projects

Parity-breaking is ubiquitous across many scales of physics, from the rotation of galaxies at the largest of scales, to the cyclotron orbits of electrons at the microscopic scale. In describing the collective dynamics of many particle systems, parity breaking effects typically originate from some form of chirality, such as angular momentum, at the level of the constituent particles. External forces can also induce chiral motion, with the primary examples being the Lorentz and Coriolis forces.

The effects of parity breaking are perhaps most strikingly seen in active matter, systems of complex particles that tend to convert energy into some directed …

A Thesis, Or Digressions On Sculptural Practice: In Which, Concepts & Influences Thereof Are Explained, Set Forth, Catalogued, Or Divulged By Way Of Commentaries To A Poem, First Conceived By The Artist, Fed Through Chatg.P.T., And Re-Edited By The Artist, To Which Are Added, Annotated References, Impressions And Ruminations Thereof, Also Including Private Thoughts & Personal Accounts Of The Artist, Jaimie An

Masters Theses

This thesis is an exercise in, perhaps a futile, attempt to trace just some of the ideas, stories, and musings I might meander through in my process. It’s not quite a map, nor is it a neat catalogue; it is a haphazard collection of tickets and receipts from a travel abroad, carelessly tossed in a carry-on, only to be stashed upon returning home. These ideas are derived from much greater thinkers and authors than myself; I am a mere collector or a translator, if that, and not a very good one, for much is lost. I do not claim comprehensive …

Simulation Of Linear And Cyclic Alkanes With Second-Order Møller–Plesset Perturbation Theory Through Adaptive Force Matching, Alexei Nikitin, Feng Wang

Chemistry & Biochemistry Faculty Publications and Presentations

Predicting ensemble properties, such as density and heat of vaporization, of small hydrocarbons is challenging due to the dispersion-dominated weak interactions between these molecules. With the adaptive force matching (AFM) method, the bonded and short-range nonbonded interactions are fitted to second-order Møller–Plesset perturbation theory (MP2) references computed with the def2-TZVP basis set. The dispersion is modeled using symmetry adapted perturbation theory (SAPT) at MP4 accuracy using the def2-TZVPD basis set. A new charge matrix decomposition technique is described to obtain partial charges in AFM. Although the models developed do not have any empirical parameters, several properties of the resulting models …