Physics Commons^™

Nonlinear Stage Of Modulational Instability In Repulsive Two-Component Bose-Einstein Condensates, S. Mossman, S. I. Mistakidis, G. C. Katsimiga, A. Romero-Ros, G. Biondini, P. Schmelcher, P. Engels, P. G. Kevrekidis

Physics Faculty Research & Creative Works

Modulational instability (MI) is a fundamental phenomenon in the study of nonlinear dynamics, spanning diverse areas such as shallow water waves, optics, and ultracold atomic gases. In particular, the nonlinear stage of MI has recently been a topic of intense exploration and has been shown to manifest, in many cases, in the generation of dispersive shock waves (DSWs). In this Letter, we experimentally probe the MI dynamics in an immiscible two-component ultracold atomic gas with exclusively repulsive interactions, catalyzed by a hard-wall-like boundary produced by a repulsive optical barrier. We analytically describe the expansion rate of the DSWs in this …

Coupled-Channel Calculations Of Fully Differential Cross Sections For Ionization In 75-Kev P + He Collisions, K. H. Spicer, N. W. Antonio, M. S. Schöffler, Michael Schulz, A. S. Kadyrov

Physics Faculty Research & Creative Works

The fully differential cross section is the most detailed quantity that can be measured or calculated to study ionization in few-body systems. For 75 keV proton collisions with helium, various experimental data are available. However, previous theoretical calculations found significant discrepancies across the entire range of data. In this work the wave-packet convergent close-coupling method is extended to calculating these cross sections for electrons ejected with energies from 1 to 75.4 eV. The approach utilizes a two-center expansion and correlated two-electron helium wave functions to describe the four-body proton-helium system. While there is good agreement with the experiment for electrons …

Efficient Parallel Processing Of Second-Generation Tdi Data For Galactic Binaries In Space-Based Gravitational Wave Missions, Xue-Hao Zhang, Soumya D. Mohanty, S. R. Valluri, Shao-Dong Zhao, Qun-Ying Xie, Yu-Xiao Liu

Physics & Astronomy Faculty Publications

Space-based gravitational wave missions such as LISA, Taiji, and Tianqin rely on the time-delay interferometry (TDI) technique to observe low-frequency signals such as Galactic binaries (GBs), massive black-hole binaries, and extreme-mass-ratio inspirals. Among these sources, resolving the large population of GBs poses a central challenge for data analysis. In this work, we present GBSIEVER-C, a pipeline implemented in C and parallelized using OpenMP (Open Multi-Processing), along with a range of additional algorithmic optimizations, including a fast implementation of second-generation TDI response modeling. It builds upon the previous MATLAB-based pipeline that demonstrated competitive performance on LISA Data Challenge (LDC) data. To …

Modeling The Basal Ganglia Network Using Leaky Integrate-And-Fire Neurons To Explore Its Role In Facilitating Purposive Saccades, Saarth Anjali Chitale

All ETDs from UAB

Saccadic eye movements provide a well-defined behavioral readout for investigating how the basal ganglia (BG) contribute to action selection. While saccades are controlled by multiple brain regions, including direct excitatory inputs from various cortices, the BG exerts a key inhibitory influence. Decades of experimental work using saccadic behavioral paradigms in non-human primates have yielded important insights into the activity of BG populations. These include the caudate nucleus, subthalamic nucleus, globus pallidus externus, and substantia nigra pars reticulata, as well as dopaminergic afferents from the substantia nigra pars compacta and efferent projections to the superior colliculus, which controls eye movements. Despite …

Gw250114: Testing Hawking’S Area Law And The Kerr Nature Of Black Holes, The Ligo Scientific Collaboration, The Virgo Collaboration, The Kagra Collaboration

Department of Physics and Astronomy Faculty Scholarship and Creative Works

The gravitational-wave signal GW250114 was observed by the two LIGO detectors with a network matched-filter signal-to-noise ratio of 80. The signal was emitted by the coalescence of two black holes with near-equal masses 𝑚1=33.6+1.2−0.8⁢𝑀⊙ and 𝑚2=32.2+0.8−1.3⁢𝑀⊙, and small spins 𝜒1,2≤0.26 (90% credibility) and negligible eccentricity 𝑒⁢≤0.03. Postmerger data excluding the peak region are consistent with the dominant quadrupolar (ℓ=|𝑚|=2) mode of a Kerr black hole and its first overtone. We constrain the modes’ frequencies to ±30% of the Kerr spectrum, providing a test of the remnant’s Kerr nature. We also examine Hawking’s area law, also known as the second law …

Gw250114: Testing Hawking’S Area Law And The Kerr Nature Of Black Holes, A. G. Abac, I. Abouelfettouh, F. Acernese, Teviet Creighton, Mario C. Diaz, R. Espinosa, J. Lawrence, Francisco Llamas Villarreal, Soma Mukherjee, Volker Quetschke, M. Ramos Arevalo, Wenhui Wang

Physics & Astronomy Faculty Publications

The gravitational-wave signal GW250114 was observed by the two LIGO detectors with a network matched-filter signal-to-noise ratio of 80. The signal was emitted by the coalescence of two black holes with near-equal masses m_{1}=33.6_{-0.8}^{+1.2}M_{⊙} and m_{2}=32.2_{-1.3}^{+0.8}M_{⊙}, and small spins χ_{1,2}≤0.26 (90% credibility) and negligible eccentricity e≤0.03. Postmerger data excluding the peak region are consistent with the dominant quadrupolar (ℓ=|m|=2) mode of a Kerr black hole and its first overtone. We constrain the modes' frequencies to ±30% of the Kerr spectrum, providing a test of the remnant's Kerr nature. We also examine Hawking's area law, also known as the second law …

Multiply Differential Study Of Detachment With Simultaneous Target Excitation In Anion-Atom Collisions, M. Schulz, F. Herrmann, W. Zhang, D. V. Chicharro, A. Dorn, M. Grieser, F. Grussie, H. Kreckel, O. Novotny, F. Trost, A. Wolf, T. Pfeifer, C. D. Schröter

Physics Faculty Research & Creative Works

We have measured momenta of electrons and recoil ions in triple coincidence with neutralized projectiles for slow collisions between various anions and target atoms. From the data we extracted triple differential momentum and angular distributions of electrons ejected in detachment, in detachment with simultaneous target ionization (DI), and in detachment with simultaneous target excitation (DE). The DI rates relative to the DE rates depend sensitively on the projectile speed and on the properties of the target.

Continuous Pump-Probe Experiment To Observe Zeeman Wave-Packet Dynamics, K. L. Romans, K. Foster, S. Majumdar, B. P. Acharya, O. Russ, A. H.N.C. De Silva, Daniel Fischer

Physics Faculty Research & Creative Works

In this work, we study the coherent dynamics of an atomic Zeeman wave packet using a continuous pump-probe scheme. A polarized Zeeman wave packet is created in laser-cooled lithium atoms via few-photon excitation by a femtosecond laser pulse, producing a state with a magnetic moment tilted relative to an external magnetic field. The subsequent Larmor precession of the atomic magnetic moment is probed via continuous ionization by an optical dipole trap (ODT) laser. The resulting ionization fragments—photoelectrons and photo ions—are detected in coincidence using a cold target recoil ion momentum spectrometer (COLTRIMS). While the ODT facilitates further cooling of the …

Euler’S Original Derivation Of Elastica Equation, Shigeki Matsutani

Euleriana

Euler derived the differential equations of elastica by the variational method in 1744, but his original derivation has never been properly interpreted or explained in terms of modern mathematics. We elaborate Euler's original derivation of elastica and show that Euler used Noether's theorem concerning the translational symmetry of elastica, although Noether published her theorem in 1918. It is also shown that his equation is essentially the static modified KdV equation which is obtained by the isometric and isoenergy conditions, known as the Goldstein-Petrich scheme.

Early Theories On Fluid Resistance And Translation Of Euler’S “Dilucidationes De Resistentia Fluidorum”, Sylvio R. Bistafa

Euleriana

In 1763, Euler published Dilucidationes de resistentia fluidorum (Explanations on the resistance of fluids), a memoir that challenges the fluid resistance theories proposed by Isaac Newton and d’Alembert. Euler's work explores the resistance experienced by solid bodies moving through fluids, critiquing both Newton's "common rule" and d’Alembert's paradox, which predicted zero resistance for non-viscous fluids. Euler's treatise is divided into two parts: the first focuses on the mathematical modeling of fluid flow patterns, while the second addresses the calculation of fluid resistance on surfaces. Despite significant advancements, Euler's work remains constrained by the limitations of non-viscous fluid assumptions, ultimately grappling …

Long-Range Quantum Entanglement In Dielectric Mu-Near-Zero Metamaterials, Olivia Mello, Larissa Vertchenko, Seth Nelson, Adrien Debacq, Durdu Guney, Eric Mazur, Michaël Lobet

Michigan Tech Publications

Entanglement is paramount in quantum information processing. Many quantum systems suffer from spatial decoherence in distances over a wavelength and cannot be sustained over short time periods due to dissipation. However, long range solutions are required for the development of quantum information processing on chip. Photonic reservoirs mediating the interactions between qubits and their environment are suggested. Recent research takes advantage of extended wavelength inside near-zero refractive index media to solve the long-range problem along with less sensitivity on the position of quantum emitters. However, those recent proposals use plasmonic epsilon near-zero waveguides that are intrinsically lossy. Here, we propose …

Performance Analysis Of Flapping-Foil Energy Harvesters Under Shear-Flow Conditions, Maqusud Alam, Bubryur Kim, Shehnaz Akhtar, Sujeen Song, Zengshun Chen, Jinwoo An

Civil Engineering Faculty Publications

Flapping-foil energy harvesters represent a promising technology for extracting energy from fluid flows, although their performance under shear-flow conditions is poorly understood. To address this research gap, we investigated the impact of power-law shear flow on the performance of flapping-foil energy harvesters. We conducted numerical simulations at different Reynolds numbers (Re = 1000, 50 000, and 500 000) under uniform-flow and shear-flow conditions. Based on the results, shear flow minimally affected the power outputs at Re = 1000 and 50 000, where viscous forces dominate the flow dynamics. However, at Re = 500 000, shear flow significantly reduced the …

Classifying Compact Radio Emission In Nearby Galaxies: A 10 Ghz Study Of Active Galactic Nuclei, Supernovae, Anomalous Microwave Emission, And Star-Forming Regions, Kristen C. Dage, Eric W. Koch, Evangelia Tremou, Kwangmin Oh, Susmita Sett, Cosima Eibensteiner, Sean T. Linden, Angiraben D. Mahida, Eric J. Murphy, Liliana E. Rivera Sandoval

Physics & Astronomy Faculty Publications

We present 115 compact radio point sources in three galaxies, NGC 5474, NGC 4631, and M51, taken in the most extended (A-)configuration of the Karl G. Jansky Very Large Array at 10 GHz. Several of these compact radio point sources have diffuse counterparts identified in previous multiband studies of resolved radio continuum emission. We find compact counterparts to eight star forming regions, four anomalous microwave emission candidates, and one supernova remnant (SN 2011dh). Nine of the compact radio sources match X-ray counterparts, the majority of which are background galaxies. These AGN are all within the D25 (isophotal diameter) of the …

Short–Range Hard–Sphere Potential And Coulomb Interaction: Deser–Trueman Formula For Rydberg States Of Exotic Atomic Systems, Gregory S. Adkins, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

In exotic atomic systems with hadronic constituent particles, it is notoriously difficult to estimate the strong-interaction correction to energy levels. It is well known that, due to the strength of the nuclear interaction, the problem cannot be solved using Wigner–Brillouin perturbation theory alone. Recently, high-angular-momentum Rydberg states of exotic atomic systems with hadronic constituents have been identified as promising candidates in the search for new physics in the low-energy sector of the Standard Model. We thus derive a generalized Deser–Trueman formula for the induced energy shift for a general hydrogenic bound state with principal quantum number n and orbital angular …

Fractional Brownian Motion With Mean-Density Interaction: A Myopic Self-Avoiding Fractional Stochastic Process, Jonathan House, Rashad Bakhshizada, Skirmantas Janušonis, Ralf Metzler, Thomas Vojta

Physics Faculty Research & Creative Works

Fractional Brownian motion is a Gaussian stochastic process with long-range correlations in time; it has been shown to be a useful model of anomalous diffusion. Here, we investigate the effects of mutual interactions in an ensemble of particles undergoing fractional Brownian motion. Specifically, we introduce a mean-density interaction in which each particle in the ensemble is coupled to the gradient of the total, time-integrated density produced by the entire ensemble. We report the results of extensive computer simulations for the mean-squared displacements and the probability densities of particles undergoing one-dimensional fractional Brownian motion with such a mean-density interaction. We find …

A Theoretical Investigation Of Photo-Induced Deformations And Transitions In Nanoscale Ferroelectrics, Carmel Dansou

Graduate Theses and Dissertations

This dissertation presents a comprehensive first-principles investigation into the interaction of light with ferroelectric materials, focusing on light-induced structural responses (photostriction) and phase transitions in Ferroelectric superlattices, epitaxially strained BiFeO3 thin films, and twodimensional NbOX2 (X = Cl, Br, I) ferroelectrics. The work aims to provide microscopic insights into how light can control the lattice structure and even the crystallographic phase in these systems, with the broader goal of informing the design of light-responsive functional materials for practical technological applications. The first part explores light-induced effects in PbTiO3/SrTiO3 superlattices with different polarization orientations. Our simulations reveal that photoexcitation modifies the …

Single-Molecule Orientation And Localization Microscopy, Sophie Brasselet, Matthew D. Lew

Electrical & Systems Engineering Publications and Presentations

Single-molecule localization microscopy (SMLM) offers enhanced spatial resolution in optical microscopy, providing detailed insights into the spatial organization of proteins in cells at the nanoscale. Over the past decade, SMLM has progressively incorporated the capability to retrieve the orientations of single molecules using their polarized dipolar emission pattern. Here we explore recent advancements in single-molecule orientation and localization microscopy (SMOLM), which yields super-resolved images of molecular three-dimensional (3D) orientations, wobble and 3D positions. This advancement opens possibilities to explore the nanoscale organization and conformation of biological molecules as well as to monitor and design local 3D optical fields in nanophotonics. …

How The Inter-Nucleon Force Shapes Emergent Collectivity And Imparts Uncertainties In Ab Initio Nuclear Observables, Kevin Becker

LSU Doctoral Dissertations

The importance of collective motion in atomic nuclei has been well-established for many decades. Even before the advent of the nuclear shell model and its much-needed answers to surprising empirical phenomena, collectivity and surface deformation have played a vital role in broadening our knowledge. Reconciling the collective and single-particle camps into a unified description required tremendous strides in the application of group theory and advances in high-performance supercomputing, and thanks to these efforts the symmetry-adapted no-core shell model, or SA-NCSM, has developed into a reliable model for the study of deformed light and medium-mass nuclei. State-of-the-art calculations reveal remarkably simple …

The Cosmoverse White Paper: Addressing Observational Tensions In Cosmology With Systematics And Fundamental Physics, Eleonora Di Valentino, Jackson Levi Said, Adam Riess, Agnieszka Pollo, Vivian Poulin, Adrià Gómez-Valent, Elena Giusarma, Et Al.

Michigan Tech Publications

The standard model of cosmology has provided a good phenomenological description of a wide range of observations both at astrophysical and cosmological scales for several decades. This concordance model is constructed by a universal cosmological constant and supported by a matter sector described by the standard model of particle physics and a cold dark matter contribution, as well as very early-time inflationary physics, and underpinned by gravitation through general relativity. There have always been open questions about the soundness of the foundations of the standard model. However, recent years have shown that there may also be questions from the observational …

Nuclear Structure Of Neutron-Deficient Cesium-126 And Cesium-127, Connor M. Gautam

Theses and Dissertations

Lifetimes of seven excited states of ¹²⁷Cs, including the states populating the isomer, were measured through a combination of spectroscopic methods. The spin and parity of the states leading up to the 171-μs isomeric level of ¹²⁶Cs were assigned for the first time, new values were measured for the lifetimes of the two isomeric states, and new evidence was presented for the assignment of a detached sequence of gamma rays to the ¹²⁶Cs nucleus.

Ab Initio Studies On Mechanical Properties Of Freestanding Ferroic Monolayers, John Malcolm Davis

Graduate Theses and Dissertations

This thesis explores the role of mechanical properties and elastic couplings in freestanding paradigmatic ferroic monolayers within the framework of density functional theory. This dissertation is comprised of three interconnected published studies: (i) establishing the elastic behavior across a temperature-driven phase transition in SnSe monolayers; (ii) thermally-driven phase transitions in graphene-like silicene, germanene, and stanene, examining the structural stability and band gap occlusion; and (iii) magnetoelastic coupling in an Ising-like CrSiTe3 monolayer, focused on assessing magnetic contributions to the material stiffness by establishing a proper non-magnetic reference.

Non-Perturbative Aspects Of Gauge Theories Through A Complex Parametrization, Antonina Maj

Dissertations, Theses, and Capstone Projects

This dissertation explores a complex matrix parametrization of four-dimensional non-Abelian gauge theories as a means of gaining analytical insights into (3+1)-dimensional QCD. The low-energy scale of non-Abelian gauge theories remains an elusive area of research even after decades of work. A key challenge lies in identifying physical, gauge-invariant degrees of freedom that are relevant to non-perturbative phenomena. In this dissertation we develop a complex parametrization of gauge fields on which gauge transformations act homogeneously, thereby enabling a manifestly gauge-invariant analytical formulation of the theory.

Chapter one constructs the complex gauge-invariant parametrization for gauge theories living on both complex projective space …

Nonlinear Diffusion, Hydrodynamic Cascades And Jamming In Kinetically Constrained Systems: Insights From Lattice Gas Models, Abhishek Raj

Dissertations, Theses, and Capstone Projects

This dissertation investigates non-linear diffusion processes and emergent dynamical phenomena in kinetically constrained lattice gases. Two central models are considered: a one-dimensional lattice gas exhibiting a diffusion cascade triggered by hydrodynamic nonlinearities and a triangular ladder exclusion model that undergoes a jamming transition. The former demonstrates stretched exponential decay consistent with non-perturbative long-time tails, while the latter illustrates how classical-quantum mappings yield insight into glassy dynamics and mobility constraints. Through a combination of numerical simulations, analytical perturbation theory, and mean-field approximations, the work uncovers mechanisms underlying anomalous transport, jamming transitions, and the breakdown of perturbative hydrodynamics.

Multi-Nuclear Magnetic Resonance (Nmr) Characterization Of Novel Materials, Tawhid Pranto

Dissertations, Theses, and Capstone Projects

The increasing reliance on batteries in commercial products, coupled with the environmental challenges posed by climate change and the limitations of fossil fuel consumption, has created strong financial and environmental incentives to explore innovative energy storage solutions. Renewable energy sources are being actively developed, but their intermittent nature necessitates efficient storage technologies, driving significant research into improving the performance of batteries, fuel cells, and capacitors.

This thesis focuses on the application of advanced Nuclear Magnetic Resonance (NMR) spectroscopy to study and understand novel materials for energy storage applications, with an emphasis on electrolytes for rechargeable lithium-ion batteries and all-solid-state batteries. …

Developments In The Lithographic Engineering Of Bi2sr2cacu2o8+Delta Mesa Terahertz-Emitting Devices, Sarah Elghazoly

Dissertations, Theses, and Capstone Projects

Devices microfabricated from the high-temperature superconducting cuprate Bi₂Sr₂CaCu₂O_8+𝛿 (Bi-2212) are a promising source of coherent terahertz radiation within the ’terahertz gap’ (0.3- 1.5 THz). A current-biased mesa patterned into the surface of a single crystal will produce electromagnetic radiation in the terahertz regime due to the naturally occurring Josephson junctions formed by the stacks of superconducting cuprate oxide planes in the material separated by insulating BiO and SrO barrier layers. Previous research has shown that by fabricating these mesas such that the geometry supports resonant cavity Fabry-Perot modes, the junctions within the mesa …

Lipid And Cholesterol Peroxidation Leads To Α-Crystallin Membrane Aggregation And Cataract Formation, Nawal K. Khadka, Preston Hazen, Oluwaseyi Akinola, Xinzhu Pu, Laxman Mainali

Boise State University Publications and Presentations

Purpose: The significant lens chaperone protein α-crystallin (αABc), comprised of αA-crystallin (αAc) and αB-crystallin (αBc) subunits, is found to form membrane-bound aggregates with age and cataract formation. However, the molecular basis for such aggregate formation is still unclear. Our research primarily aims to elucidate the effect of lipids (phospholipids and sphingolipids) and cholesterol (Chol) peroxidation on the aggregation of αAc, αBc, and αABc to bovine lens nuclear membrane (NM).

Methods: Lipid and Chol peroxidation was induced by a photosensitized peroxidation reaction, and topographical images of NM and oxidized-NM (Ox-NM) with and without αAc, αBc, or αABc were obtained using atomic …

Quantum Entanglement Correlations In The Proton On The Light-Front, Eric Kolbusz

Dissertations, Theses, and Capstone Projects

In this work we gather results on information theory applied to proton tomography. We start by analyzing the quantum entanglement of momentum, spin-flavor, and color degrees of freedom (d.o.f.) in the leading valence-quark state of the proton on the light front using standard information theoretical tools, leveraging model wavefunctions by Brodsky and Schlumpf to obtain numerical predictions. Light-cone perturbation theory allows us to introduce the one-gluon correction in the sub-leading Fock state and study the entanglement of the gluonic d.o.f. We find weak entanglement in the spatial d.o.f. of the valence quarks, and significantly stronger entanglement in the analogous d.o.f. …

Electrical Characterization Of Germanium Tin Alloys And Devices For Space Reliability, Kevin K. Choe

Theses and Dissertations

GeSn (germanium tin) alloys are potentially well suited for near-mid infrared space optoelectronic applications. Alloys of GeSn have similar properties to group III-V and mercury-cadmium-telluride semiconductors and are compatible with cost-effective complementary metal oxide semiconductor (CMOS) manufacturing technology. Recent progress in non-equilibrium remote plasma-enhanced chemical vapor deposition (RPECVD) has enabled the crystalline growth of GeSn with Sn concentrations of up to 10% without Sn surface segregation. Several experimental studies in previous literature report CVD- or molecular beam epitaxy (MBE)-grown GeSn alloys achieving a direct bandgap with 6%-9% Sn content. This novel growth technique opens opportunities for a cost-effective, next-generation optical …

Gw250114: Testing Hawking’S Area Law And The Kerr Nature Of Black Holes, Jaclyn (Jax) Sanders, Ligo-Virgo-Kagra (Lvk)

Physics Faculty Research and Publications

The gravitational-wave signal GW250114 was observed by the two LIGO detectors with a network matched-filter signal-to-noise ratio of 80. The signal was emitted by the coalescence of two black holes with near-equal masses 𝑚1=33.6^+1.2 _−0.8⁢𝑀⊙ and 𝑚2=32.2^+0.8 _−1.3⁢𝑀⊙, and small spins 𝜒1,2≤0.26 (90% credibility) and negligible eccentricity 𝑒⁢≤0.03. Postmerger data excluding the peak region are consistent with the dominant quadrupolar (ℓ=|𝑚|=2) mode of a Kerr black hole and its first overtone. We constrain the modes’ frequencies to ±30% of the Kerr spectrum, providing a test of the remnant’s Kerr nature. We also examine Hawking’s area law, …

Relevant Deformations Of Brane Brick Models, Georgios P. Goulas

Dissertations, Theses, and Capstone Projects

The thesis studies relevant deformations of 2d gauge theories with $\mathcal{N}=(0,2)$ supersymmetry, realized on the worldvolume of D1-branes probing toric Calabi-Yau 4-folds. Brane brick models are the primary means for engineering such theories and streamlining their connection to geometry. In this thesis, we relevant deformations of brane brick models, focusing on a specific class of deformations in which the initial and final theories are both described by brane brick models. Relevant deformations serve as an additional, systematic way of generating these theories, as well as uncovering connections between them. Within the framework of brane engineering, these deformations acquire a geometric …