Human Second Metacarpal Nanocrystal Analysis,
2024
DePaul University
Human Second Metacarpal Nanocrystal Analysis, William Abramovich
DePaul Discoveries
Female human bones dated to the 6th - 8th century CE were uncovered in Greding Germany after archaeologists discovered a medieval cemetery. Age-at-death estimates have been determined, and data from several techniques are currently being analyzed to learn more about these samples. The purpose of this project is to study the diaphyses of the second metacarpal (mc2) bones excavated using wide-angle x-ray scattering data collected at beamline 1-ID of the Advanced Photon Source at Argonne National Laboratory. The diffraction data were refined using the Rietveld method to obtain lattice (‘a’ and ‘c’) parameter values …
Design Of Long-Distance Entanglement Distribution Protocols For Quantum Networks,
2024
Louisiana State University and Agricultural and Mechanical College
Design Of Long-Distance Entanglement Distribution Protocols For Quantum Networks, Stav Haldar
LSU Doctoral Dissertations
Future quantum technologies such as quantum communication, quantum sensing, and distributed quantum computation, will rely on networks of shared entanglement between spatially separated nodes. Distributing entanglement between these nodes, especially over long distances, currently remains a challenge, due to limitations resulting from the fragility of quantum systems, such as photon losses, non-ideal measurements, and quantum memories with short coherence times. In the absence of full-scale fault-tolerant quantum error correction, which can in principle overcome these limitations, we should understand the extent to which we can circumvent these limitations. In this work, we provide improved protocols and policies for entanglement distribution …
Testing Of An Organic Metal Halide Perovskite For Fast Neutron Detection,
2024
The Ohio State University
Testing Of An Organic Metal Halide Perovskite For Fast Neutron Detection, Wyatt Panaccione, Zhifang Shi, Praneeth Kandlakunta, Taylor M. Nichols, Susan White, Jinsong Huang, Lei R. Cao
Student Publications
In this work, we synthesized and characterized the Methylhydrazinium Lead Trichloride MHyPbCl3(CH3NH2NH2PbCl3) perovskite as a fast neutron detector. The high hydrogen density of MHyPbCl3 enables efficient energy conversion from a fast neutron into a recoiled proton through the 1H(n,n)1H elastic scattering interaction, thereby, allowing for direct charge detection. Through IV characterization and X-Ray excitation, the crystal demonstrated a high resistivity at 4.43E11 ω cm and a good mobility-lifetime product (μτ) of 9.1E-3 cm2/V respectively, under C60/BCP/Cu and Au contact configuration to form an ohmic-ohmic …
Investigation Of Cooperative Subradiance In Dense Ultracold Rubidium Ensembles,
2024
Old Dominion University
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 …
Diffuse Reflectance Spectroscopy For Optical Characterizations Of Orthotopic Head And Neck Cancer Models In Vivo,
2024
University of Kentucky
Diffuse Reflectance Spectroscopy For Optical Characterizations Of Orthotopic Head And Neck Cancer Models In Vivo, Pranto Soumik Saha, Jing Yan, Caigang Zhu
Markey Cancer Center Faculty Publications
We demonstrated an easy-to-build, portable diffuse reflectance spectroscopy device along with a Monte Carlo inverse model to quantify tissue absorption and scattering-based parameters of orthotopic head and neck cancer models in vivo. Both tissue-mimicking phantom studies and animal studies were conducted to verify the optical spectroscopy system and Monte Carlo inverse model for the accurate extraction of tissue optical properties. For the first time, we reported the tissue absorption and scattering coefficients of mouse normal tongue tissues and tongue tumor tissues. Our in vivo animal studies showed reduced total hemoglobin concentration, lower tissue vascular oxygen saturation, and increased tissue scattering …
Generating Bessel Beams With An Elastomeric Replica Of A Weevil Carapace,
2024
Ateneo de Manila University
Generating Bessel Beams With An Elastomeric Replica Of A Weevil Carapace, Paz Victoria T. Ramos, Michie Vianca D. De Vera, Raphael Guerrero
Physics Faculty Publications
We generate a zero-order Bessel beam with a laser beam focused onto an elastomeric replica of a weevil carapace scale. Carapace surface structures are imprinted on an elastomeric cast via soft lithography. The output Bessel beam exhibits the expected properties of non-diffraction over a propagation range of 30 cm. The width of the central spot at a propagation distance of 25 cm is 296:8 μm, corresponding to a replicated weevil scale with a diameter of 64.3 μm acting as an annular slit. Self-healing of the beam after encountering a wire obstruction is also observed.
Coherent Backscattering Under Conditions Of Electromagnetically Induced Transparency In Ultracold Rubidium,
2024
Old Dominion University
Coherent Backscattering Under Conditions Of Electromagnetically Induced Transparency In Ultracold Rubidium, Joshua D. Carter
Physics Theses & Dissertations
This dissertation presents experimental results of coherent backscattering of light in an ultracold ensemble of rubidium atoms confined in a magneto optical trap under conditions of electromagnetically induced transparency (EIT) in a cascade-type system. Electromagnetically induced transparency was investigated experimentally in both a counterpropagating and orthogonal laser geometry and compared to theory. The experimental results were largely in good agreement with theory. Coherent backscattering was then measured with and without an EIT control field present to investigate the modification, if any, that EIT has on the enhancement of the coherent backscattering cone. The results indicated that the electromagnetically induced transparency …
Accelerator Based Techniques Iba To Characterize Archeological Artefacts: Case Study Of Ancient Ceramics,
2024
Physics Department, Faculty of Science, Beirut Arab University, Lebanon
Accelerator Based Techniques Iba To Characterize Archeological Artefacts: Case Study Of Ancient Ceramics, Ahmad Reslan, Mohamad Roumie, Sandrine Elaigne, Bilal Nsouli, Mahmoud Korek
BAU Journal - Science and Technology
Ion beam analysis techniques IBA, in particular proton induced X-ray emission PIXE, play an effective and efficient role in the characterization of cultural heritage objects. As early as the 1970s, PIXE technique was applied as reliable analytical technique to determine the elemental composition of archeological artefacts, where many accelerator laboratories worldwide are still involved in such applications. It has the advantage to be multi-elemental (Na to Pb) with major, minor and trace element analysis down to part per million or ppm, fast (few minutes per sample), non-destructive and its possible combination with other IBA techniques that can reveal other information. …
Defect-Free Nanowelding Of Bilayer Snse Nanoplates,
2024
Max Planck Institute of Microstructure Physics
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 …
Simulation Of Linear And Cyclic Alkanes With Second-Order Møller–Plesset Perturbation Theory Through Adaptive Force Matching,
2024
University of Arkansas, Fayetteville
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 …
Collisional Broadening And Shift Of Rubidium 42D5/2 → N2F Line Shapes With Helium And Electrons,
2024
Air Force Institute of Technology
Collisional Broadening And Shift Of Rubidium 42D5/2 → N2F Line Shapes With Helium And Electrons, Dillon T. Nice
Theses and Dissertations
Line shapes for three rubidium 42D5/2 → n2F transitions were collected using pump probe spectroscopy. Broadening rates for Rb-He collisions ranged from 139–171 MHz/Torr and shift rates ranged from 113–146 MHz/Torr. Then, line shapes were collected at different alkali densities to measure electron density. Electron density had a clear “runaway ionization density threshold” around 1.5×1013 cm−3. The three transitions agreed within 2% on the observed fractional ionization when calculated using the observed Stark width but did not agree on the observed fractional ionization when calculated using the observed Stark shift. These results …
Phase Error Scaling Law In Two-Wavelength Adaptive Optics,
2024
Air Force Institute of Technology
Phase Error Scaling Law In Two-Wavelength Adaptive Optics, Milo W. Hyde Iv, Matthew Kalensky, Michael J. Spencer
Faculty Publications
We derive a simple, physical, closed-form expression for the optical-path difference (OPD) of a two-wavelength adaptive-optics (AO) system. Starting from Hogge and Butts’ classic OPD variance integral expression, we apply Mellin transform techniques to obtain series and asymptotic solutions to the integral. For realistic two-wavelength AO systems, the former converges slowly and has limited utility. The latter, on the other hand, is a simple formula in terms of the separation between the AO sensing (i.e., the beacon) and compensation (or observation) wavelengths. We validate this formula by comparing it to the OPD variances obtained from the aforementioned series and direct …
Pt-Symmetry And Eigenmodes,
2024
Portland State University
Pt-Symmetry And Eigenmodes, Tamara Gratcheva
University Honors Theses
Spectra of systems with balanced gain and loss, described by Hamiltonians with parity and time-reversal (PT) symmetry is a rich area of research. This work studies by means of numerical techniques, how eigenvalues and eigenfunctions of a Schrodinger operator change as a gain-loss parameter changes. Two cases on a disk with zero boundary conditions are considered. In the first case, within the enclosing disk, we place a parity (P) symmetric configuration of three smaller disks containing gain and loss media, which does not have PT-symmetry. In the second case, we study a PT-symmetric configuration …
A Computational Investigation Of Wood Selection For Acoustic Guitar,
2024
Liberty University
A Computational Investigation Of Wood Selection For Acoustic Guitar, Jonah Osterhus
Senior Honors Theses
The acoustic guitar is a stringed instrument, often made of wood, that transduces vibrational energy of steel strings into coupled vibrations of the wood and acoustic pressure waves in the air. Variations in wood selection and instrument geometry have been shown to affect the timbre of the acoustic guitar. Computational methods were utilized to investigate the impact of material properties on acoustic performance. Sitka spruce was deemed the most suitable wood for guitar soundboards due to its acoustic characteristics, strength, and uniform aesthetic. Mahogany was deemed to be the best wood for the back and sides of the guitar body …
Effects Of Post-Deposition Annealing On Room Temperature Deposited Zinc Oxide,
2024
Macalester College
Effects Of Post-Deposition Annealing On Room Temperature Deposited Zinc Oxide, Ishan Rayen
Macalester Journal of Physics and Astronomy
This study focuses on thin film deposition of ZnO onto a glass slide using magnetron sputtering. The focus of the study is to understand the effects of post-deposition annealing temperatures. The goal is to optimize crystal quality, conductivity, and transparency. The results attempt to answer the effects of room temperature deposition and changes in film properties once annealed. Annealing temperatures ranged from 100°C to 400°C with an annealing time of 30 minutes. This found an ideal temperature of 250°C for post-deposition annealing, resulting in approximately 3.86 times more conductivity with little to no decrease in transparency. However crystal quality did …
Optical Transport Of Ultracold Atoms,
2024
University of San Diego
Optical Transport Of Ultracold Atoms, David Vera
Undergraduate Honors Theses
At temperatures near absolute zero, bosons form a macroscopic quantum state that can be manipulated and imaged in a very controlled and tunable way. To reach these extreme temperatures near absolute zero, advanced methods in cooling, including laser and evaporative cooling, must be used. In addition to these techniques for cooling, atoms must also be held up against the constant pull of gravity, so additional trapping techniques using lasers and magnets are used. In our lab at University of San Diego, we are implementing a tunable lens system (TLS) to optically transfer atoms to a more optically accessible location. A …
Entanglement With Neutral Atoms In The Simulation Of Nonequilibrium Dynamics Of One-Dimensional Spin Models,
2024
University of New Mexico - Main Campus
Entanglement With Neutral Atoms In The Simulation Of Nonequilibrium Dynamics Of One-Dimensional Spin Models, Anupam Mitra
Physics & Astronomy ETDs
Quantum entanglement is a key ingredient for quantum information processing with capabilities beyond that of classical computation. We study the generation and role of entanglement in the dynamics of spin-1/2 models, both for the design of quantum gates for general-purpose quantum computation and for quantum simulation of interacting spin models. We introduce the neutral atom Mølmer-Sørensen gate, involving rapid adiabatic Rydberg dressing interleaved in a spin-echo sequence. We show its robustness to quasi-static experimental imperfections and favorable scaling with the time-energy scales of Rydberg-mediated entanglement generation. In quantum simulation, we consider critical behavior in quench dynamics of transverse field Ising …
The Rubidium Magneto-Optical Trap: Designing A Robust System For Measurement & Control,
2024
Bridgewater State University
The Rubidium Magneto-Optical Trap: Designing A Robust System For Measurement & Control, Thomas Melody
Honors Program Theses and Projects
This thesis is a culmination of our efforts to construct a robust and flexible opto-mechanical system to fully deliver and control all of the parameters related to the required laser wavelength, polarization, power, beam size, and directionality for both the pump and the re-pump laser beams, delivered from two different lasers, necessary for neutral-atom laser trapping and cooling. This is an extension of the neutral Rubidium Magneto-Optical Trap (MOT) at BSU which afford a macroscopic scale collection of cold atoms where the effective governing laws of physics are quantum in nature rather than classical. My predecessors had done work on …
The Ring-Closing Reaction Of Cyclopentadiene Probed With Ultrafast
X‑Ray Scattering,
2024
Brown University
The Ring-Closing Reaction Of Cyclopentadiene Probed With Ultrafast X‑Ray Scattering, Lisa Huang, Lauren Bertram, Lingyu Ma, Nathan Goff, Stuart W. Crane, Asami Odate, Thomas Northey, Andrés Moreno Carrascosa, Mats Simmermacher, Sri Bhavya Muvva, Joseph D. Geiser, Matthew J. Lueckheide, Zane Phelps, Mengning Liang, Xinxin Cheng, Ruaridh Forbes, Joseph S. Robinson, Matthew J. Hayes, Felix Allum, Alice E. Green, Kenneth Lopata, Artem Rudenko, Thomas J. A. Wolf, Martin Centurion, Daniel Rolles, Michael P. Minitti, Adam Kirrander, Peter M. Weber
Martin Centurion Publications
The dynamics of cyclopentadiene (CP) following optical excitation at 243 nm was investigated by time-resolved pump−probe X-ray scattering using 16.2 keV X-rays at the Linac Coherent Light Source (LCLS). We present the first ultrafast structural evidence that the reaction leads directly to the formation of bicyclo[2.1.0]pentene (BP), a strained molecule with three- and four-membered rings. The bicyclic compound decays via a thermal backreaction to the vibrationally hot CP with a time constant of 21 ± 3 ps. A minor channel leads to ring-opened structures on a subpicosecond time scale.
Nonlinear Rogue Wave Generation For All-Optical Switching In Optical Fibers And Photonic Integrated Circuits,
2024
Bridgewater State University
Nonlinear Rogue Wave Generation For All-Optical Switching In Optical Fibers And Photonic Integrated Circuits, Samuel Alexander Bechtold
Honors Program Theses and Projects
For my thesis we discuss the history of optics, electronics and photonicsproviding a framework from which I investigate the viability of engineering a Photonic Integrated Circuit (PIC) that takes advantage of the nonlinear optical process known as Rogue Wave Generation (RWG) for an all-optical switching mechanism that is capable of switching speeds in the Peta-Hertz (PHz) frequency regime. This topic is introduced through a discussion of how technological advances such as the transistor, laser and optical fiber made modern computing and telecommunications possible. This is followed by a theoretical explanation of the nonlinear optical phenomena known as supercontinuum generation (SCG) …
