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Fermion-Induced Electroweak Symmetry Non-Restoration Via Temperature-Dependent Masses, Yu Hang Ng Aug 2022

Fermion-Induced Electroweak Symmetry Non-Restoration Via Temperature-Dependent Masses, Yu Hang Ng

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

Standard Model (SM) and many extensions of SM predict that the electroweak (EW) symmetry was restored in the early universe when the temperature was around 160 GeV. However, recent studies showed that the interactions between some new scalars and SU(2)_L Higgs doublet(s) can cause the EW symmetry to remain broken at temperatures well above the EW scale in certain renormalizable extensions of SM. In this study, we found that new fermions from renormalizable models can also induce this EW symmetry non-restoration effect, provided that they have the appropriate temperature-dependent masses. These masses can arise naturally from the interactions between the …


Study Of Thermoelectric And Lattice Dynamics Properties Of 2d Layered Mx (M = Sn, Pb; X = S, Se, Te) And Zrs2 Compounds Using First-Principles Approach, Abhiyan Pandit Aug 2022

Study Of Thermoelectric And Lattice Dynamics Properties Of 2d Layered Mx (M = Sn, Pb; X = S, Se, Te) And Zrs2 Compounds Using First-Principles Approach, Abhiyan Pandit

Graduate Theses and Dissertations

The aim of this dissertation is the investigation of thermoelectric and lattice dynamics properties of two-dimensional (2D) MX (M = Sn, Pb; X = S, Se, Te) and ZrS2 compounds based on the first-principles density functional theory. The dimensionality reduction (e.g., using 2D structure) of bulk materials is found to have enhanced thermoelectric efficiency. This enhancement is attributed to the increase of the Seebeck coefficient as a result of higher electronic density of states near the Fermi level in low-dimensional materials. In addition, lowering the dimensionality increases phonon scattering near interfaces and surfaces in 2D materials, which leads to a …


Materials Design For Energy Applications Using Ab- Initio Calculations, Hind Hemaidee Alqurashi Aug 2022

Materials Design For Energy Applications Using Ab- Initio Calculations, Hind Hemaidee Alqurashi

Graduate Theses and Dissertations

The structural, dynamical, electronic, and thermoelectric properties of rock-salt and wurtzite Cd1-xZnxO alloys, VTiRhZ (Al, Ga, In, Si, Ge, Sn) and ZrTiRhZ (Ge, Sn) quaternary Heusler alloys (QHAs) were investigated using density functional theory (DFT) and semi-classical Boltzmann transport theory. From these calculations, the alloys were identified as potential materials for future thermoelectric applications. Furthermore, the magnetic and spin-polarization properties of these QHAs were investigated. The total magnetic moments were found to be integer values for all QHAs. In addition, all studied QHAs except VTiRhAl possess a half-metallic behavior with a 100% spin-polarization. The half-metallic ferromagnetic behavior makes them promising …


61st Annual Rocky Mountain Conference On Magnetic Resonance Jul 2022

61st Annual Rocky Mountain Conference On Magnetic Resonance

Rocky Mountain Conference on Magnetic Resonance

Final program, abstracts, and information about the 61st annual meeting of the Rocky Mountain Conference on Magnetic Resonance, co-endorsed by the Colorado Section of the American Chemical Society and the Society for Applied Spectroscopy. Held in Copper Mountain, Colorado, July 25-29, 2022.


A Simple Parameterization To Enhance The Computational Time In The Three Layer Dry Deposition Model For Smooth Surfaces, Omar M.M. Nofal, Omar Al-Jaghbeer, Zaid Bakri, Tareq Hussein Jul 2022

A Simple Parameterization To Enhance The Computational Time In The Three Layer Dry Deposition Model For Smooth Surfaces, Omar M.M. Nofal, Omar Al-Jaghbeer, Zaid Bakri, Tareq Hussein

Michigan Tech Publications, Part 1

Optimization of dry deposition velocity calculation has been of great interest. Every time, determining the value of the concentration boundary layer (CBL) thickness led to a waste of numerical calculation time, which appears as a huge time in large-scale climate models. The goal of this study is to optimize the numerical calculation time in the three-layer deposition model for smooth surfaces through the development of a MATLAB code that can parameterize the appropriate concentration boundary layer height (y+cbl) and internal integral calculation intervals for each particle diameter Dp (0.01–100 µm) and friction velocity u* (0.01–100 m/s). The particle concentration, as …


Phase Transitions And Resilience Of The Magnetic Dual Chiral Density Wave Phase At Finite Temperature And Density, William Gyory, Vivian De La Incera Jul 2022

Phase Transitions And Resilience Of The Magnetic Dual Chiral Density Wave Phase At Finite Temperature And Density, William Gyory, Vivian De La Incera

Physics & Astronomy Faculty Publications

We study the phase transitions at finite temperature and density of the magnetic dual chiral density wave (MDCDW) phase. This spatially inhomogeneous phase emerges in cold, dense QCD in the presence of a strong magnetic field. Starting from the generalized Ginzburg-Landau (GL) expansion of the free energy, we derive several analytical formulas that enable fast numerical computation of the expansion coefficients to arbitrary order, allowing high levels of precision in the determination of the physical dynamical parameters, as well as in the transition curves in the temperature vs chemical potential plane at different magnetic fields. At magnetic fields and temperatures …


Monitoring Fast Superconducting Qubit Dynamics Using A Neural Network, G. Koolstra, N. Stevenson, S. Barzili, L. Burns, K. Siva, S. Greenfield, W. Livingston, A. Hashim, R. K. Naik, J. M. Kreikebaum, K. P. O'Brien, D. I. Santiago, Justin Dressel, I. Siddiqi Jul 2022

Monitoring Fast Superconducting Qubit Dynamics Using A Neural Network, G. Koolstra, N. Stevenson, S. Barzili, L. Burns, K. Siva, S. Greenfield, W. Livingston, A. Hashim, R. K. Naik, J. M. Kreikebaum, K. P. O'Brien, D. I. Santiago, Justin Dressel, I. Siddiqi

Mathematics, Physics, and Computer Science Faculty Articles and Research

Weak measurements of a superconducting qubit produce noisy voltage signals that are weakly correlated with the qubit state. To recover individual quantum trajectories from these noisy signals, traditional methods require slow qubit dynamics and substantial prior information in the form of calibration experiments. Monitoring rapid qubit dynamics, e.g., during quantum gates, requires more complicated methods with increased demand for prior information. Here, we experimentally demonstrate an alternative method for accurately tracking rapidly driven superconducting qubit trajectories that uses a long short-term memory (LSTM) artificial neural network with minimal prior information. Despite few training assumptions, the LSTM produces trajectories that include …


Computational Models To Detect Radiation In Urban Environments: An Application Of Signal Processing Techniques And Neural Networks To Radiation Data Analysis, Jose Nicolas Gachancipa Jul 2022

Computational Models To Detect Radiation In Urban Environments: An Application Of Signal Processing Techniques And Neural Networks To Radiation Data Analysis, Jose Nicolas Gachancipa

Beyond: Undergraduate Research Journal

Radioactive sources, such as uranium-235, are nuclides that emit ionizing radiation, and which can be used to build nuclear weapons. In public areas, the presence of a radioactive nuclide can present a risk to the population, and therefore, it is imperative that threats are identified by radiological search and response teams in a timely and effective manner. In urban environments, such as densely populated cities, radioactive sources may be more difficult to detect, since background radiation produced by surrounding objects and structures (e.g., buildings, cars) can hinder the effective detection of unnatural radioactive material. This article presents a computational model …


Atomic Gradiometry Based On The Interference Of Microwave Optical Sidebands, Kaleb L. Campbell Jul 2022

Atomic Gradiometry Based On The Interference Of Microwave Optical Sidebands, Kaleb L. Campbell

Optical Science and Engineering ETDs

We describe a novel pulsed magnetic gradiometer based on the optical interference of sidebands generated using two spatially separated alkali vapor cells. The sidebands are produced with high efficiency using parametric frequency conversion of a probe beam interacting with Rubiduim 87 atoms in a coherent superposition of magnetically sensitive hyperfine ground states. First, experimental evidence of the sideband process is described for both steady-state and pulsed operation. Then, a theoretical framework is developed that accurately models sideband generation based on density matrix formalism. The gradiometer is then constructed using two spatially separated vapor cells, and a beat-note is generated. The …


Search For The Radiative Penguin Decays B0 → K 0 SK 0 S Γ In The Belle Experiment, H. B. Jeon, K. H. Kang, H. Park, I. Adachi, H. Aihara, S. Al Said, D. M. Asner, H. Atmacan, T. Aushev, R. Ayad, V. Babu, S. Bahinipati, P. Behera, K. Belous, J. Bennett, F. Bernlochner, M. Bessner, V. Bhardwaj, B. Bhuyan, Milind Purohit, Et. Al. Jul 2022

Search For The Radiative Penguin Decays B0 → K 0 SK 0 S Γ In The Belle Experiment, H. B. Jeon, K. H. Kang, H. Park, I. Adachi, H. Aihara, S. Al Said, D. M. Asner, H. Atmacan, T. Aushev, R. Ayad, V. Babu, S. Bahinipati, P. Behera, K. Belous, J. Bennett, F. Bernlochner, M. Bessner, V. Bhardwaj, B. Bhuyan, Milind Purohit, Et. Al.

Faculty Publications

We report results from the first search for the rare penguin-dominated decay mode B0→K 0 S K 0 Sγ, which can result from the production of tensor mesons f(1270) and f'(1525) in association with a photon. The search uses the full data sample of 772×106  BB̅ pairs collected with the Belle detector at the KEKB asymmetric-energy e+e− collider. No statistically significant signals are observed in the K 0 S K 0 S invariant mass range 1  GeV/c2K 0 S K 0 S/c2, and the following upper …


The Photoionization Dynamics, Electronic Spectroscopy, And Excited State Photochemistry Of Alco And Aloc, Vincent J. Esposito, Joseph S. Francisco Jul 2022

The Photoionization Dynamics, Electronic Spectroscopy, And Excited State Photochemistry Of Alco And Aloc, Vincent J. Esposito, Joseph S. Francisco

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The high cosmic abundance of carbon monoxide (CO) and the ubiquitous nature of aluminum-coated dust grains sets the stage for the production of weakly bound triatomic molecules AlCO (X 2Π) and AlOC (X 2Π) in circumstellar envelopes of evolved stars. Following desorption of cold AlCO and AlOC from the dust grain surface, incoming stellar radiation in the 2–9 eV wavelength range (visible to vacuum ultraviolet) will drive various photochemical processes. Ionization to the singlet cation state will cause an immediate Al–X (X = C, O) bond dissociation to form Al+ (1S) and CO (X 1 …


Search For Flavor-Changing Neutral Current Interactions Of The Top Quark And Higgs Boson In Final States With Two Photons In Proton-Proton Collisions At √S =13 Tev, A. Tumasyan Jul 2022

Search For Flavor-Changing Neutral Current Interactions Of The Top Quark And Higgs Boson In Final States With Two Photons In Proton-Proton Collisions At √S =13 Tev, A. Tumasyan

Department of Physics and Astronomy: Faculty Publications

Proton-proton interactions resulting in final states with two photons are studied in a search for the signature of flavor-changing neutral current interactions of top quarks (t) and Higgs bosons (H). The analysis is based on data collected at a center-of-mass energy of 13 TeV with the CMS detector at the LHC, corresponding to an integrated luminosity of 137 fb−1. No significant excess above the background prediction is observed. Upper limits on the branching fractions (Ɓ) of the top quark decaying to a Higgs boson and an up (u) or charm …


Neutron Interferometry Using A Single Modulated Phase Grating, Ivan J. Hidrovo Giler Jul 2022

Neutron Interferometry Using A Single Modulated Phase Grating, Ivan J. Hidrovo Giler

LSU Master's Theses

Neutron grating interferometry provides information on phase and small-angle scatter in addition to attenuation. Previously, phase grating moiré interferometers (PGMI) with two or three phase gratings have been developed. These phase-grating systems use the moiré far-field technique to avoid the need for high-aspect absorption gratings used in Talbot-Lau interferometers (TLI) which reduce the neutron flux reaching the detector. We demonstrate through simulations a novel phase grating interferometer system for cold neutrons that requires a single modulated phase grating (MPG) for phase-contrast imaging, as opposed to the two or three phase gratings in previously employed PGMI systems. We compare the MPG …


Prospects For Lattice Qfts On Curved Riemann Manifolds, Richard C. Brower, Casey E. Berger, George T. Fleming, Andrew D. Gasbarro, Evan K. Owen, Timothy G. Raben, Chung I. Tan, Evan S. Weinberg Jul 2022

Prospects For Lattice Qfts On Curved Riemann Manifolds, Richard C. Brower, Casey E. Berger, George T. Fleming, Andrew D. Gasbarro, Evan K. Owen, Timothy G. Raben, Chung I. Tan, Evan S. Weinberg

Physics: Faculty Publications

Conformal or near conformal Quantum Field Theories QFT) would benefit from a rigorous non-perturbative lattice formulation beyond the flat Euclidean space, Rd. Although all UV complete QFT are generally acknowledged to be perturbatively renormalizable on smooth Riemann manifolds, non-perturbative realization on simplicial lattices (triangulation) encounter difficulties as the UV cut-off is removed. We review the Quantum Finite Element (QFE) method that combines classical Finite Element with new quantum counter terms designed to address this. The construction for maximally symmetric spaces (Sd, R × Sd−1 and AdSd+1) is outlined with numerical tests on R × S2 and a description of theoretical …


Quantum Counter-Terms For Lattice Field Theory On Curved Manifolds, Evan K. Owen, Casey E. Berger, Richard C. Brower, George T. Fleming, Andrew D. Gasbarro, Timothy G. Raben Jul 2022

Quantum Counter-Terms For Lattice Field Theory On Curved Manifolds, Evan K. Owen, Casey E. Berger, Richard C. Brower, George T. Fleming, Andrew D. Gasbarro, Timothy G. Raben

Physics: Faculty Publications

We present the necessity of counter-terms for Quantum Finite Element (QFE) simulations of ϕ4 theory on non-trivial simplicial manifolds with semi-regular lattice spacing. By computing the local cut-off dependence of UV divergent diagrams we found that the symmetries of the continuum theory are restored for ϕ4 theory on the manifolds S2 and S2 × R in the weak coupling regime [1, 2]. Here we consider the construction of non-perturbative local counter-terms in an attempt to approach the strong coupling Wilson-Fisher IR fixed point.


Probing Charm Quark Dynamics Via Multiparticle Correlations In Pb-Pb Collisions At √SNn =5.02 Tev, A. Tumasyan Jul 2022

Probing Charm Quark Dynamics Via Multiparticle Correlations In Pb-Pb Collisions At √SNn =5.02 Tev, A. Tumasyan

Department of Physics and Astronomy: Faculty Publications

Multiparticle azimuthal correlations of prompt D0 mesons are measured in Pb-Pb collisions at a nucleon-nucleon center-of-mass energy of √sNN = 5.02 TeV. For the first time, a four-particle cumulant method is used to extract the second Fourier coefficient of the azimuthal distribution (ν2) of D0 mesons as a function of event centrality and the D0 transverse momentum. The ratios of the four-particle v2 values to previously measured two-particle cumulant results provide direct experimental access to event-by-event fluctuations of charm quark azimuthal anisotropies. These ratios are also found to be comparable to …


Surpassing The Standard Quantum Limit Using An Optical Spring, Torrey Cullen Jul 2022

Surpassing The Standard Quantum Limit Using An Optical Spring, Torrey Cullen

LSU Doctoral Dissertations

In 1916, Albert Einstein predicted the existence of gravitational waves based on his new theory of general relativity. He predicted an accelerating mass with a non-zero quadrupole moment would emit energy in the form of gravitational waves. Often referred to as ripples in space-time, gravitational waves are extremely small by the time reach Earth, potentially having traveled hundreds of megaparsecs. It is common for these ripples in space-time to stretch and squeeze matter 1000 times smaller than the width of a proton.
Laser interferometer observatories were first built in the 1990s in the US and Europe, and as sensitivity improvements …


Resource Estimation For Quantum Simulation Algorithms, Changhao Yi Jul 2022

Resource Estimation For Quantum Simulation Algorithms, Changhao Yi

Physics & Astronomy ETDs

A major application of quantum computers is simulating other quantum systems that are intractable to simulate classically. The broad family of algorithms for this problem go by the name of quantum simulation. Product formulas provide resource efficient and practical methods to simulate Hamiltonian dynamics. In this thesis, we study the resource estimation of quantum simulation by product formula from two aspects. First, we provide a detailed analysis of the algorithm itself. Using the effective Hamiltonian perspective, we successfully reduce the circuit complexity of quantum phase estimation and digital adiabatic simulation. Second, we analyze the performance of dynamical decoupling, a widely-used …


Asymmetric Control Of Light At The Nanoscale, Christos Argyropoulos Jul 2022

Asymmetric Control Of Light At The Nanoscale, Christos Argyropoulos

Department of Electrical and Computer Engineering: Faculty Publications

Breaking reciprocity at the nanoscale can produce directional formation of images due to the asymmetric nonlinear optical response of subwavelength anisotropic resonators. The self-induced passive non-reciprocity has advantages compared to magnet or time modulation approaches and may impact both classical and quantum photonics.


Modelling Spherical Aberration Detection In An Analog Holographic Wavefront Sensor, Emma Branigan, Suzanne Martin, Matthew Sheehan, Kevin Murphy Jul 2022

Modelling Spherical Aberration Detection In An Analog Holographic Wavefront Sensor, Emma Branigan, Suzanne Martin, Matthew Sheehan, Kevin Murphy

Conference Papers

The analog holographic wavefront sensor (AHWFS) is a simple and robust solution to wavefront sensing in turbulent environments. Here, the ability of a photopolymer based AHWFS to detect refractively generated spherical aberration is modelled and verified.


Measurement Of |Vcb| Using The Semileptonic Decay Λb → Λcμνμ, Scott Edward Ely Jul 2022

Measurement Of |Vcb| Using The Semileptonic Decay Λb → Λcμνμ, Scott Edward Ely

Dissertations - ALL

A preliminary measurement of the quark-mixing parameter |Vcb| using the exclusive decay Λ0b→ Λ+c μ−νμ is presented. A sample of Λb semileptonic decays is provided by √s = 13TeV proton-proton collisions collected by the LHCb detector in 2017. Λ0b → Λ+c μ−νμX decays are identified from muon tracks, combined with a Λc baryon. The ground state Λ0b → Λ+c μ−νμ is isolated by a fit to the Λb corrected mass spectrum. The raw yield NRaw(Λ0b → Λ+c μ−νμ) is corrected, and the semileptonic width ΓMeas. (Λ0b → Λ+c μ−νμ) is obtained. Lattice QCD calculations predict ΓTh.(Λ0b → Λ+c μ−νμ)/|Vcb|2. A …


Characterization Of Scintillation Light In Large Liquid Argon Detectors And The Implications For Proton Decay Searches, Kyle Spurgeon Jul 2022

Characterization Of Scintillation Light In Large Liquid Argon Detectors And The Implications For Proton Decay Searches, Kyle Spurgeon

Dissertations - ALL

The Deep Underground Neutrino Experiment (DUNE) is a planned long baseline neutrino experi- ment. The detector will be comprised of four modules with 10kt of active volume each, making it an ideal target to neutrino oscillation physics and searches for proton decay. ProtoDUNE-SP was a single-phase liquid argon time projection chamber - a prototype for the first far detector module of DUNE with an active volume of 700 tons operating until 2020. It was installed at the CERN Neutrino Platform and took particle beam and cosmic ray data over its two year lifespan. Liquid argon scin- tillation light is still …


Study Of Radiative Corrections In The Muon Scattering Experiment, Lin Li Jul 2022

Study Of Radiative Corrections In The Muon Scattering Experiment, Lin Li

Theses and Dissertations

The root-mean-square (rms) radius of the proton charge is a fundamental quantity. In 2010, the studies of muonic hydrogen with high precision found a notably smaller value than the one from earlier non-muonic measurements. This discrepancy has led to theoretical and experimental investigations. A missing measurement in determining the proton radius is muon scattering, a measurement that the MUon Scattering Experiment (MUSE) collaboration proposed at Paul Scherrer Institute (PSI). MUSE will measure elastic electron-proton and muon-proton scattering data with positively and negatively charged beams in a four-momentum-transfer square range from Q2 = 0.002 to 0.08 GeV2 . Each of …


The Close Agn Reference Survey (Cars): Tracing The Circumnuclear Star Formation In The Super-Eddington Nls1 Mrk 1044, N. Winkel, T. A. Davis, I. Smirnova-Pinchukova, V. N. Bennert, F. Combes, M. Gaspari, K. Jahnke, J. Neumann, C. P. O'Dea, M. Pérez-Torres, M. Singha, G. R. Tremblay, H. W. Rix Jul 2022

The Close Agn Reference Survey (Cars): Tracing The Circumnuclear Star Formation In The Super-Eddington Nls1 Mrk 1044, N. Winkel, T. A. Davis, I. Smirnova-Pinchukova, V. N. Bennert, F. Combes, M. Gaspari, K. Jahnke, J. Neumann, C. P. O'Dea, M. Pérez-Torres, M. Singha, G. R. Tremblay, H. W. Rix

Physics

Context. The host galaxy conditions for rapid supermassive black hole growth are poorly understood. Narrow-line Seyfert 1 (NLS1) galaxies often exhibit high accretion rates and are hypothesized to be prototypes of active galactic nuclei (AGN) at an early stage of their evolution.

Aims. We present adaptive optics (AO) assisted VLT MUSE NFM observations of Mrk 1044, the nearest super-Eddington accreting NLS1. Together with archival MUSE WFM data, we aim to understand the host galaxy processes that drive Mrk 1044’s black hole accretion.

Methods. We extracted the faint stellar continuum emission from the AGN-deblended host and performed spatially resolved emission line …


Foldy-Wouthuysen Transformation In Strong Magnetic Fields And Relativistic Corrections For Quantum Cyclotron Energy Levels, Albert Wienczek, Christopher Moore, Ulrich D. Jentschura Jul 2022

Foldy-Wouthuysen Transformation In Strong Magnetic Fields And Relativistic Corrections For Quantum Cyclotron Energy Levels, Albert Wienczek, Christopher Moore, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

We carry out a direct iterative Foldy-Wouthuysen transformation of a general Dirac Hamiltonian coupled to an electromagnetic field, including the anomalous magnetic moment. The transformation is carried out through an iterative disentangling of the particle and antiparticle Hamiltonians in the expansion for higher orders of the momenta. The time-derivative term from the unitary transformation is found to be crucial in supplementing the transverse component of the electric field in higher orders. Final expressions are obtained for general combined electric and magnetic fields, including strong magnetic fields. The time derivative of the electric field is shown to enter only in the …


Method Of Hybrid Control Based Of Dynamic Objects Of Neuro-Fuzzy Inference, Noilakhon Yakubova Jun 2022

Method Of Hybrid Control Based Of Dynamic Objects Of Neuro-Fuzzy Inference, Noilakhon Yakubova

Karakalpak Scientific Journal

The Results of interaction of the work is development of a method of control that allows simplifying, automating and unifying the process of design of the hybrid systems which are a basis of modern automation. To achieve a definite purpose, a method of control of a technical object based on the construction of an adaptive system of neuro-fuzzy inference is developed. The objects of the system of neuro-fuzzy inference are the classical and neuro-fuzzy models of control. Information exchange between models is provided by means of the developed hybrid control system. The result of the interaction of the two models …


Development Of The Implementation Of Iot Monitoring System Based On Node-Red Technology, Anvar Kabulov, Inomjon Yarashov, Salamat Mirzataev Jun 2022

Development Of The Implementation Of Iot Monitoring System Based On Node-Red Technology, Anvar Kabulov, Inomjon Yarashov, Salamat Mirzataev

Karakalpak Scientific Journal

This article describes how to design and implement a process for storing environmental information in a database using the Internet of Things. The problems that need to be solved with the help of this IoT system are the growing demand for forecasts in the world, the demand of the world market for a new sustainable method of implementing the digitization environment through the Internet of Things. The design was implemented using Arduino, Node-Red and sensors, selected when choosing a component based on the required parameters and sent to the database for monitoring and processing. A study of previous work and …


Evaluation Of Natural Radioactivity And Radiation Hazards Of Soils Around Petroleum Products Marketing Company Using Gamma Ray Spectrometry, Dayo A. Ayeni, Festus M. Adebiyi Jun 2022

Evaluation Of Natural Radioactivity And Radiation Hazards Of Soils Around Petroleum Products Marketing Company Using Gamma Ray Spectrometry, Dayo A. Ayeni, Festus M. Adebiyi

Tanzania Journal of Science

This study aimed at evaluating natural radioactivity and radiation hazards of soils around a petroleum product marketing company due to anthropogenic influences using gamma ray spectrometry. Top soils (5 cm deep) were collected from diverse locations inside the premises of the Company using standard analytical technique, while control samples were acquired at approximately 200 m from the study area. Mean activity concentrations of the radionuclides in the test soils were 89.36 Bq/kg for 40K, 92.1 Bq/kg for 238U and 10.95 Bq/kg for 232Th, which are more than that of control samples with statistically significant differences. Assessment of the radiological levels …


Ultrafast Electron Diffraction: Visualizing Dynamic States Of Matter, D. Filipetto, P. Musumed, R. K. Li, B. J. Siwick, M. R. Otto, Martin Centurion, J. P.F. Nunes Jun 2022

Ultrafast Electron Diffraction: Visualizing Dynamic States Of Matter, D. Filipetto, P. Musumed, R. K. Li, B. J. Siwick, M. R. Otto, Martin Centurion, J. P.F. Nunes

Martin Centurion Publications

Since the discovery of electron-wave duality, electron scattering instrumentation has developed into a powerful array of techniques for revealing the atomic structure of matter. Beyond detecting local lattice variations in equilibrium structures with the highest possible spatial resolution, recent research efforts have been directed towards the long sought-after dream of visualizing the dynamic evolution of matter in real-time. The atomic behavior at ultrafast timescales carries critical information on phase transition and chemical reaction dynamics, the coupling of electronic and nuclear degrees of freedom in materials and molecules, the correlation between structure, function and previously hidden metastable or nonequilibrium states of …


Ultra-High Carrier Mobilities In Ferroelectric Domain Wall Corbino Cones At Room Temperature, Conor J. Mccluskey, Matthew G. Colbear, James P.V. Mcconville, Shane J. Mccartan, Jesi R. Maguire, Michele Conroy, Kalani Moore, Alan Harvey, Felix Trier, Ursel Bangert, Alexei Gruverman, Manuel Bibes, Amit Kumar, Raymong G.P. Mcquaid, J. Marty Gregg Jun 2022

Ultra-High Carrier Mobilities In Ferroelectric Domain Wall Corbino Cones At Room Temperature, Conor J. Mccluskey, Matthew G. Colbear, James P.V. Mcconville, Shane J. Mccartan, Jesi R. Maguire, Michele Conroy, Kalani Moore, Alan Harvey, Felix Trier, Ursel Bangert, Alexei Gruverman, Manuel Bibes, Amit Kumar, Raymong G.P. Mcquaid, J. Marty Gregg

Alexei Gruverman Publications

Recently, electrically conducting heterointerfaces between dissimilar band-insulators (such as lanthanum aluminate and strontium titanate) have attracted considerable research interest. Charge transport has been thoroughly explored and fundamental aspects of conduction firmly established. Perhaps surprisingly, similar insights into conceptually much simpler conducting homointerfaces, such as the domain walls that separate regions of different orientations of electrical polarisation within the same ferroelectric band-insulator, are not nearly so well-developed. Addressing this disparity, we herein report magnetoresistance in approximately conical 180° charged domain walls, which occur in partially switched ferroelectric thin film single crystal lithium niobate. This system is ideal for such measurements: firstly, …