Physics Commons^™

Exciton Dynamics, Interaction, And Transport In Monolayers Of Transition Metal Dichalcogenides, Saroj Chand

Dissertations, Theses, and Capstone Projects

Monolayers Transition metal dichalcogenides (TMDs) have attracted much attention in recent years due to their promising optical and electronic properties for applications in optoelectronic devices. The rich multivalley band structure and sizable spin-orbit coupling in monolayer TMDs result in several optically bright and dark excitonic states with different spin and valley configurations. In the proposed works, we have developed experimental techniques and theoretical models to study the dynamics, interactions, and transport of both dark and bright excitons.

In W-based monolayers of TMDs, the momentum dark exciton cannot typically recombine optically, but they represent the lowest excitonic state of the system …

The Roaring Lion Of Berlin: The Life, Thought, And Influence Of Eugen Dühring, Arden Roy

Undergraduate Research Symposium

The life and influence of 19th-century German polymath Eugen Dühring remain but a mere footnote in the history of ideas, being primarily relegated to the status of little more than a theoretical rival to Marxism in the German socialist movement and the occasional object of Freidrich Nietzsche's rhetorical flogging. Despite the current consensus on the subject, Eugen Dühring was a scholar of vast, remarkable learnedness, contributing greatly to philosophy, economics, and the natural sciences. The aim of this talk will be to clear the fog surrounding the life and work of the controversial blind scholar and give an account of …

On The Exact Helium Wave Function Expansion, Ii, An Exponential Modulated Form, Carl W. David

Chemistry Education Materials

A 1¹S wave function’s expansion for 2 electron atoms and ions is proposed employing an appropriate exponential factor and Fock’s logarithmic terms. The leading coefficient’s are presented.

Non-Hermitian Physics Achieved Via Non-Local Gilbert Damping, Trevor Joshua Macintosh

Electronic Theses and Dissertations

In this thesis, we study a simple model for a ferromagnet starting with Heisenberg exchange interaction including the effects of dissipation. Gilbert damping is consid- ered and generalized from an on-site term to include non-local damping interactions between neighbouring spins. The strength of the damping interaction between neigh- bours can be tuned individually to provide the freedom to change the parameters of the system and explore the range of possible non-Hermitian behaviours. We consider the example of a honeycomb lattice ferromagnet featuring Dirac cones and two sub- lattices and analyse the resulting spectra and eigenstates. Under periodic boundary conditions, we …

Superconductivity Of Amorphous And Crystalline Re–Lu Films, Serafim Teknowijoyo, Armen Gulian

Mathematics, Physics, and Computer Science Faculty Articles and Research

We report on superconducting properties of a novel material: rhenium-lutetium films. Different compositions of RexLu binary are explored from x ≈ 3.8 to close to pure Re stoichiometry. The highest critical temperature, up to 7 K, is obtained for x ≈ 10.5 in accordance with electron dispersive spectroscopy results. Depending on the deposition conditions, polycrystalline or amorphous films are obtainable, both of which are interesting for practical use. Crystalline structure of polycrystalline phase is identified as a non-centrosymmetric superconductor using grazing incidence x-ray diffractometry. Superconducting properties were characterized both resistively and magnetically. Magnetoresistivity and AC/DC susceptibility measurements allowed …

Year-2 Progress Report On Numerical Methods For Bgk-Type Kinetic Equations, Steven M. Wise, Evan Habbershaw

Faculty Publications and Other Works -- Mathematics

In this second progress report we expand upon our previous report and preliminary work. Specifically, we review some work on the numerical solution of single- and multi-species BGK-type kinetic equations of particle transport. Such equations model the motion of fluid particles via a density field when the kinetic theory of rarefied gases must be used in place of the continuum limit Navier-Stokes and Euler equations. The BGK-type equations describe the fluid in terms of phase space variables, and, in three space dimensions, require 6 independent phase-space variables (3 for space and 3 for velocity) for each species for accurate simulation. …

Evanescent Wave Quartz-Enhanced Photoacoustic Spectroscopy Employing A Side-Polished Fiber For Methane Sensing, Cian F. Twomey, Gabriele Biagi, Albert A. Ruth, Marilena Giglio, Vincenzo Spagnolo, Liam O'Faolain, Anton J. Walsh

Cappa Publications

We present an all-fiber-based laser gas analyzer (LGA) employing quartz-enhanced photoacoustic spectroscopy (QEPAS) and a side-polished fiber (SPF). The LGA comprises a custom quartz tuning fork (QTF) with 0.8 mm prong spacing, two acoustic micro-resonators (mR) located on either side of the prong spacing, and a single-mode fiber containing a 17 mm polished section passing through both mRs and QTF. The SPF polished face is positioned to enable the evanescent wave (EW) to create a photoacoustic wave and excite the fundamental flexural mode of the QTF. Sensor performance was demonstrated using methane in nitrogen gas mixtures, with CH4" role="presentation" style="box-sizing: …

Radon Plate-Out And The Effects Of Airflow And Electric Charge For Dark Matter Experiments, Faith Fang

SMU Journal of Undergraduate Research

The Cryogenic Dark Matter Search (SuperCDMS) is an international collaboration designed to search for and detect dark matter particles, which make up ~85% of the matter in the universe. The plate-out, or deposition of naturally occurring radioactive decay byproducts onto surfaces, can create backgrounds that interfere with dark matter detection experiments. In the first series of these experiments, we analyze the amount of radon progeny, 214Pb and 214Bi, that plate-out on polycarbonate samples while controlling factors such as electric charge and airflow. These samples are exposed to radon-spiked nitrogen gas in a polycarbonate wind tunnel to simulate plate-out conditions in …

Buzzard To Cardinal: Improved Mock Catalogs For Large Galaxy Surveys, Chun-Hao To, Joseph Derose, Risa H. Wechsler, Eli Rykoff, Hao-Yi Wu, Susmita Adhikari, Elisabeth Krause, Eduardo Rozo, David H. Weinberg

Physics Faculty Publications and Presentations

We present the Cardinal mock galaxy catalogs, a new version of the Buzzard simulation that has been updated to support ongoing and future cosmological surveys, including the Dark Energy Survey (DES), DESI, and LSST. These catalogs are based on a one-quarter sky simulation populated with galaxies out to a redshift of z = 2.35 to a depth of m_r = 27. Compared to the Buzzard mocks, the Cardinal mocks include an updated subhalo abundance matching model that considers orphan galaxies and includes mass-dependent scatter between galaxy luminosity and halo properties. This model can simultaneously fit galaxy clustering and group–galaxy …

Genome-Wide Profiling Of Novel Conserved Zea Mays Micrornas Along With Their Key Biological, Molecular And Cellular Targets And Validation Using An Rt-Pcr Platform, Abdul Baqi, Sami Ullah, Muhammad Ayub, Muhammad Zafar Saleem, Ghulam Mustafa Khan, Asad Ullah

Karbala International Journal of Modern Science

MicroRNAs (miRNAs), which are typically non-coding RNAs that start off as endogenous molecules and regulate post-transcriptional levels of gene expression by mRNA degradation or translational repression. They are 18–26 nucleotides long, evolutionarily conserved and essential for predicting novel miRNAs in a variety of plants. Maize (Zea mays) is a significant food and forage crop in the globe today. In the present study, many maize miRNAs have been found to be associated with both plant development and responses to stress. In this study, 66 unique conserved maize miRNAs from 65 different miRNA families were predicted using several genomics-based methods …

The Role Of Cu (0-0.03) And Zn (0.02) Substitution On The Structural, Optical And Magnetic Properties Of Mgo Nanoparticles, S. Naseem Shah, Atif Dawar, Yasmeen Bibi, Abid Ali, M. Asif Siddiqui

Karbala International Journal of Modern Science

The co-precipitation method was employed to prepared Cu (0-0.03) and Zn (0.02) dual doped MgO nanoparticles. The secondary phases of CuO and Cu₂O were observed along with the cubical phase of MgO. The doping induced effect was noticed for the crystallite size variations (14.39-19.89 nm). The morphological transformation from spherical to rice-like shape were observed. The estimated values of optical bandgap (4.66-4.45 eV) were well correlated with the crystallite size and dopant concentrations. The ferromagnetic ordering was observed at room temperature and the enchantment in the coercivity (142.27 Oe) with Zn (0.02) doping was noticed. Such type of …

Beyond Standard Model: Structure Factors Of Models Of Different Quarks And Neutrinos As Spinning Structures Made Of Basic Fractional Charges +- E/3, Polievkt Perov

College of Arts & Sciences Faculty Works

We consider a possible line of “elementary” particles as composite spinning structures made of just two basic elementary particles of charges + e/3 and -e/3. In considered structures, up to 3 basic charges can be on the axis of rotation and other charges can be in a revolving motion about the axis. In addition to the simplest structures of quarks, an electron and a neutral particle containing mostly one or no charges on the axis of rotation, suggested initially in [4], we analyze possible spatial structures of spinning composite particles having 2 or 3 charges on the axis of rotation. …

Experimental Realization Of The Peregrine Soliton In Repulsive Two-Component Bose-Einstein Condensates, A. Romero-Ros, Garyfallia C. Katsimiga, Simeon I. Mistakidis, S. Mossman, G. Biondini, P. Schmelcher, P. Engels, P. G. Kevrekidis

Physics Faculty Research & Creative Works

We Experimentally Realize the Peregrine Soliton in a Highly Particle-Imbalanced Two-Component Repulsive Bose-Einstein Condensate in the Immiscible Regime. The Effective Focusing Dynamics and Resulting Modulational Instability of the Minority Component Provide the Opportunity to Dynamically Create a Peregrine Soliton with the Aid of an Attractive Potential Well That Seeds the Initial Dynamics. The Peregrine Soliton Formation Is Highly Reproducible, And Our Experiments Allow Us to Separately Monitor the Minority and Majority Components, And to Compare with the Single Component Dynamics in the Absence or Presence of the Well with Varying Depths. We Showcase the Centrality of Each of the Ingredients …

Galactic Gamma-Ray Diffuse Emission At Tev Energies With Hawc Data, R. Alfaro, C. Alvarez, J. C. Arteaga-Velázquez, K. P. Arunbabu, D. Avila Rojas, R. Babu, Et Al.

Michigan Tech Publications, Part 2

Galactic gamma-ray diffuse emission (GDE) is emitted by cosmic rays (CRs), ultra-relativistic protons, and electrons, interacting with gas and electromagnetic radiation fields in the interstellar medium. Here we present the analysis of teraelectronvolt diffuse emission from a region of the Galactic plane over the range in longitude of l ∈ [43°, 73°], using data collected with the High Altitude Water Cherenkov (HAWC) detector. Spectral, longitudinal, and latitudinal distributions of the teraelectronvolt diffuse emission are shown. The radiation spectrum is compatible with the spectrum of the emission arising from a CR population with an index similar to that of the observed …

Programmable Heisenberg Interactions Between Floquet Qubits, Long B. Nguyen, Yosep Kim, Akel Hashim, Noah Goss, Brian Marinelli, Bibek Bhandari, Debmalya Das, Ravi K. Naik, John Mark Kreikebaum, Andrew N. Jordan, David I. Santiago, Irfan Siddiqi

Mathematics, Physics, and Computer Science Faculty Articles and Research

The trade-off between robustness and tunability is a central challenge in the pursuit of quantum simulation and fault-tolerant quantum computation. In particular, quantum architectures are often designed to achieve high coherence at the expense of tunability. Many current qubit designs have fixed energy levels and consequently limited types of controllable interactions. Here by adiabatically transforming fixed-frequency superconducting circuits into modifiable Floquet qubits, we demonstrate an XXZ Heisenberg interaction with fully adjustable anisotropy. This interaction model can act as the primitive for an expressive set of quantum operations, but is also the basis for quantum simulations of spin systems. To illustrate …

The Dynamic Universe: Realizing The Potential Of Classical Time Domain And Multimessenger Astrophysics, Steve B. Howell, D. Andrew Howell, R. A. Street, Melinda Soares-Furtado, Brian Jackson, Thomas P. Greene

Physics Faculty Publications and Presentations

In parallel with the multi-messenger revolution, major advances in time-domain astronomy across multiple science disciplines relevant to astrophysics are becoming more urgent to address. Aside from electromagnetic observations of gravitational wave events and explosive counterparts, there are a number of “classical” astrophysical areas that require new thinking for proper exploration in the time domain. How NASA, NSF, ESA, and ESO consider the 2020 USA Decadal Survey within the astronomy community, as well as the worldwide call to support and expand time domain and multi-messenger astrophysics, it is crucial that all areas of astrophysics, including stellar, galactic, Solar System, and exoplanetary …

Low Complexity Radio Frequency Interference Mitigation For Radio Astronomy Using Large Antenna Array, Zaid Bin Tariq, Teviet Creighton, Louis Percy Dartez, Naofal Al-Dhahir, Murat Torlak

Physics and Astronomy Faculty Publications and Presentations

With the ongoing growth in radio communications, there is an increased contamination of radio astronomical source data, which hinders the study of celestial radio sources. In many cases, fast mitigation of strong radio frequency interference (RFI) is valuable for studying short lived radio transients so that the astronomers can perform detailed observations of celestial radio sources. The standard method to manually excise contaminated blocks in time and frequency makes the removed data useless for radio astronomy analyses. This motivates the need for better radio frequency interference (RFI) mitigation techniques for array of size M antennas. Although many solutions for mitigating …

Treatment Of Oil Refinery Wastewater Polluted By Heavy Metal Ions Via Adsorption Technique Using Non-Valuable Media: Cadmium Ions And Buckthorn Leaves As A Study Case, Salem Jawad Alhamd, Mohammed Nsaif Abbas, Mehrdad Manteghian, Thekra Atta Ibrahim, Karar Dawood Salman Jarmondi

Karbala International Journal of Modern Science

This study focuses on the removal of cadmium ions generated by oil refinery wastewater, employing an agricultural by-product. Buckthorn leaves, sourced from Baghdad and Diyala provinces, underwent preparation, including washing, drying, crushing, and sieving before being utilized in experiments. Batch experiments were conducted using simulated solutions to assess the impact of six key adsorption design parameters: pH, cadmium concentration, agitation speed, contact time, adsorbent dosage, and temperature. The highest adsorption efficiency, reaching 94.4367%, was directly correlated with contact time, adsorbent dosage, pH value, and agitation speed, and inversely related to other variables. Morphological studies on the treated adsorbent, indicated structural …

Quantum Scars And Regular Eigenstates In A Chaotic Spinor Condensate, Bertrand Evrard, Andrea Pizzi, Simeon I. Mistakidis, Ceren B. Dag

Physics Faculty Research & Creative Works

Quantum Many-Body Scars Consist Of A Few Low-Entropy Eigenstates In An Otherwise Chaotic Many-Body Spectrum, And Can Weakly Break Ergodicity Resulting In Robust Oscillatory Dynamics. The Notion Of Quantum Many-Body Scars Follows The Original Single-Particle Scars Introduced Within The Context Of Quantum Billiards, Where Scarring Manifests In The Form Of A Quantum Eigenstate Concentrating Around An Underlying Classical Unstable Periodic Orbit. A Direct Connection Between These Notions Remains An Outstanding Problem. Here, We Study A Many-Body Spinor Condensate That, Owing To Its Collective Interactions, Is Amenable To The Diagnostics Of Scars. We Characterize The System's Rich Dynamics, Spectrum, And Phase …

Stimulated Raman Spectroscopy With Widely Tunable Probe Pulse For Measuring Dissolved Inorganic Phosphorus In The Great Lakes, Nathan Gregory Drouillard

Electronic Theses and Dissertations

The eutrophication of freshwater ecosystems remains a persistent global problem threatening biodiversity, drinking water, and economic interests. Among the Laurentian Great Lakes, Lake Erie is most severely impacted by eutrophication, experiencing annual harmful algal blooms that are thought to result from excess phosphate deposition into the ecosystem. Efforts to study and mitigate the effects of eutrophication require accurate monitoring of phosphate concentrations. The current method for measuring phosphate, the molybdenum blue method, suffers from signal interference. In this thesis, I recommend Raman spectroscopy as a label-free, reagent-free spectroscopic technique for accurately measuring phosphate in freshwater. I verify the Raman spectrum …

What Does ‘(Non)-Absoluteness Of Observed Events’ Mean?, Emily Adlam

Mathematics, Physics, and Computer Science Faculty Articles and Research

Recently there have emerged an assortment of theorems relating to the ‘absoluteness of emerged events,’ and these results have sometimes been used to argue that quantum mechanics may involve some kind of metaphysically radical non-absoluteness, such as relationalism or perspectivalism. However, in our view a close examination of these theorems fails to convincingly support such possibilities. In this paper we argue that the Wigner’s friend paradox, the theorem of Bong et al and the theorem of Lawrence et al are all best understood as demonstrating that if quantum mechanics is universal, and if certain auxiliary assumptions hold, then the world …

Light That Appears To Come From A Source That Does Not Exist, Itamar Stern, Yakov Bloch, Einav Grynszpan, Merav Kahn, Yakir Aharonov, Justin Dressel, Eliahu Cohen, John C. Howell

Mathematics, Physics, and Computer Science Faculty Articles and Research

Superoscillatory, band-limited functions oscillate faster than their fastest Fourier component. Superoscillations have been intensively explored recently as they give rise to many out-of-the-spectrum phenomena entailing both fundamental and applied significance. We experimentally demonstrate a form of superoscillations which is manifested by light apparently coming from a source located far away from the actual one. These superoscillations are sensed through sharp transverse shifts in the local wave vector at the minima of a pinhole diffraction pattern. We call this phenomenon “optical ventriloquism.”

Physics 100 Level Laboratory Data Collection Tables, Kalani Hettiarachchilage

Open Educational Resources

The physics 100-level laboratory part demonstrates and applies the material learned from related classes. This document shows guidelines for collecting data and analyzing them by using Microsoft Excel. Laboratory components of PHY 114/ PHY 206/SLS 261 (Introduction to Physics and Nature of Physical Processes), PHY116/PHY 121 (Physics I and General Physics I), and PHY 156/PHY 161 (Physics II and General Physics II) at College of Staten Island are in-person mandatory sessions for students and it is required to pass to receive a passing grade for that class. This part is taught by different instructors. Although everyone is supposed to follow …

Radio Measurements Of The Depth Of Air-Shower Maximum At The Pierre Auger Observatory, A. Abdul Halim, P. Abreu, M. Aglietta, I. Allekotte, K. Almeida Cheminant, A. Almela, B. Fick, D. Nitz, K. Nguyen, A. Puyleart, Et Al.

Michigan Tech Publications, Part 2

The Auger Engineering Radio Array (AERA), part of the Pierre Auger Observatory, is currently the largest array of radio antenna stations deployed for the detection of cosmic rays, spanning an area of 17 km2 with 153 radio stations. It detects the radio emission of extensive air showers produced by cosmic rays in the 30-80 MHz band. Here, we report the AERA measurements of the depth of the shower maximum (Xmax), a probe for mass composition, at cosmic-ray energies between 1017.5 and 1018.8 eV, which show agreement with earlier measurements with the fluorescence technique at the Pierre Auger Observatory. We show …

Demonstrating Agreement Between Radio And Fluorescence Measurements Of The Depth Of Maximum Of Extensive Air Showers At The Pierre Auger Observatory, A. Abdul Halim, P. Abreu, M. Aglietta, I. Allekotte, K. Almeida Cheminant, A. Almela, B. Fick, D. Nitz, K. Nguyen, A. Puyleart, Et Al.

Michigan Tech Publications, Part 2

We show, for the first time, radio measurements of the depth of shower maximum (Xmax) of air showers induced by cosmic rays that are compared to measurements of the established fluorescence method at the same location. Using measurements at the Pierre Auger Observatory we show full compatibility between our radio and the previously published fluorescence dataset, and between a subset of air showers observed simultaneously with both radio and fluorescence techniques, a measurement setup unique to the Pierre Auger Observatory. Furthermore, we show radio Xmax resolution as a function of energy and demonstrate the ability to make competitive high-resolution Xmax …

Questioning Reality: The Progressive Development Of Modern Physics, Joshua Lancman

STEM for Success Showcase

Humanity has a tendency to divide time. The past is distinct from the present which is entirely separate from the future. In supposedly 20-20 vision history is neatly divided into different sections, distinct eras with sharp lines between them. What is present and in the future is always modern. What is past is something else with another name.

Yet time is not divided so neatly. We know this living through it: years and decades blend into one another in a non-uniform progression. To divide human history into separate eras is a necessary simplification, as it helps to ascribe order onto …

Synchronicity: An Analysis Of Einstein's Halfway Rule, Preslava Nikolova

Rushton Journal of Undergraduate Humanities Research

For the modern world to function, Global Positioning System satellites must synchronize to clocks on Earth. This paper examines a concept that underlies GPS systems, namely Albert Einstein’s halfway rule—the idea that a line of simultaneity exists between two events in different systems. This essay discusses how Einstein used conventionalist methods to establish ½ as a constant value for σ to take advantage of the property of symmetry.

Designing A Convection-Cloud Chamber For Collision-Coalescence Using Large-Eddy Simulation With Bin Microphysics, Aaron Wang, Mikhail Ovchinnikov, Fan Yang, Silvio Schmalfuss, Raymond A. Shaw

Michigan Tech Publications, Part 2

Collisional growth of cloud droplets is an essential yet uncertain process for drizzle and precipitation formation. To improve the quantitative understanding of this key component of cloud-aerosol-turbulence interactions, observational studies of collision-coalescence in a controlled laboratory environment are needed. In an existing convection-cloud chamber (the Pi Chamber), collisional growth is limited by low liquid water content and short droplet residence times. In this work, we use numerical simulations to explore various configurations of a convection-cloud chamber that may intensify collision-coalescence. We employ a large-eddy simulation (LES) model with a size-resolved (bin) cloud microphysics scheme to explore how cloud properties and …

Source Data For "Flowering Of Developable 2d Crystal Shapes In Closed, Fluid Membranes", Hao Wan, Geunwoong Jeon, Weiyue Xin, Gregory M. Grason, Maria M. Santore

Data and Datasets

Source data for "Flowering of Developable 2D Crystal Shapes in Closed, Fluid Membranes".

Robust Interventions In Network Epidemiology, Erik Weis

Graduate College Dissertations and Theses

Which individual should we vaccinate to minimize the spread of a disease? Designing optimal interventions of this kind can be formalized as an optimization problem on networks, in which we have to select a budgeted number of dynamically important nodes to receive treatment that optimizes a dynamical outcome. Describing this optimization problem requires specifying the network, a model of the dynamics, and an objective for the outcome of the dynamics. In real-world contexts, these inputs are vulnerable to misspecification---the network and dynamics must be inferred from data, and the decision-maker must operationalize some (potentially abstract) goal into a mathematical objective …