Atomic, Molecular and Optical Physics Commons^™

Development Of A Vector Magnetometer Based On Electromagnetically Induced Transparency In 87rb Atomic Vapor, Alexander Toyryla

Undergraduate Honors Theses

We present progress towards the development of an atomic magnetometer capable of accurate scalar and vector magnetic field measurements with high sensitivity and no need for external calibration. The proposed device will use the interaction between a bi-chromatic laser field and rubidium vapor to derive magnetic field magnitude and direction from measured amplitudes of Electromagnetically Induced Transparency (EIT) resonances. Since the proposed method requires precision control of light polarization, we observe the performance capabilities of a liquid crystal device to dynamically rotate the polarization of the laser field. Another goal in this project is to establish a polarization locking mechanism …

Experimental Investigation Of All-Optical Production Of Metastable Krypton, Joshua Carl Frechem

Physics Theses & Dissertations

Metastable production of noble gases requires significant energy due to their filled valence shells. These transitions from the ground state are in the vacuum ultraviolet and extreme ultraviolet, which are relatively inaccessible to lasers. This necessitates the use of either electron/ion bombardment via inefficient glow discharges or the use of high-power lasers and nonlinear processes. The all-optical production efficiency using these high-power lasers promises to be orders of magnitude higher than glow discharges, but far more costly. This work looks to improve all-optical production of metastable krypton (Kr*) through the use of a commercially available vacuum ultraviolet lamp with a …

Co-Planar Waveguides For Microwave Atom Chips, Morgan Logsdon

Undergraduate Honors Theses

This thesis describes research to develop co-planar waveguides (CPW) for coupling microwaves from mm-scale coaxial cables into 50 μm-scale microstrip transmission lines of a microwave atom chip. This new atom chip confines and manipulates atoms using spin-specific microwave AC Zeeman potentials and is particularly well suited for trapped atom interferometry. The coaxial-to-microstrip coupler scheme uses a focused CPW (FCPW) that shrinks the microwave field mode while maintaining a constant 50 Ω impedance for optimal power coupling. The FCPW development includes the simulation, design, fabrication, and testing of multiple CPW and microstrip prototypes using aluminum nitride substrates. Notably, the FCPW approach …

Porous Silicon Photonics For Label-Free Interferometric Biosensing And Flat Optics, Tahmid Hassan Talukdar

All Dissertations

This dissertation uses porous silicon as a material platform to explore novel optical effects in three domains: (i) It studies dispersion engineering in integrated waveguides to achieve high performance group index sensing. With proper design parameters, the sensor waveguides can theoretically achieve 6 times larger group index shift compared to the actual bulk effective refractive index shift. We demonstrate the guided mode confinement factor to be a key parameter in design and implementation of these waveguides. (ii) It explores multicolor laser illumination to experimentally demonstrate perceptually enhanced colorimetric sensing, overcoming the limitations faced by many contemporary colorimetric sensors. Our technique …

Design, Fabrication, And Characterization Of An Array Of Graphene Based Variable Capacitors, Millicent Nkirote Gikunda

Graduate Theses and Dissertations

Since it was first isolated and characterized in 2004, graphene has shown the potential for a technological revolution. This is due to its amazing physical properties such as high electrical conductivity, high thermal conductivity, and extreme flexibility. Freestanding graphene membranes naturally possesses an intrinsic rippled structure, and these ripples are in constant random motion even room temperatures. Occasionally, the ripples undergo spontaneous buckling (change of curvature from concave to convex and vice versa) and the potential energy associated with this is a double well potential. This movement of graphene is a potential source of vibrational energy.

In this dissertation, we …

Dissociative Excitation, Ionization, And Fragmentation Processes For Nitrogen, Oxygen, Methane, And Water Molecules By Electron Bombardment, M. Gochitashvili, R. Lomsazde, D. Kuparashvili, O. Taboridze, Roman Ya. Kezerashvili

Publications and Research

Electron–impact ionization and fragmentation of molecules are investigated by the chromatography mass-spectrometry device. While the excitation processes are investigated by an optical spectroscopy method. The spectral analysis is performed in the vacuum ultraviolet 50-130 nm spectral regions. The absolute value of the fragmentation cross-section in the dissociative ionization and excitation processes is determined. Measurements are performed in the electron energy range 25-120eV for ionization and 200-500eV for excitation processes respectively.

Dispersion In High Temperature Superconductors, Lazar Novakovic

Undergraduate Research Symposium Podium Presentations

Superconductors are used in many different industries: Efficient power transmission, Maglev train, MRIs

Design And Characterization Of Frequency Tripling Mirrors, Amir Khabbazi Oskouei

Optical Science and Engineering ETDs

Aperiodic stacks of dielectric low- and high-index films can be designed to enhance third-harmonic generation (THG) in reflection of near infrared laser pulses using computer optimization. Numerical and analytical results suggest that the TH energy increases rapidly with increasing number of films and the ratio of the high and low index.

Our optical matrix based THG model that takes into account the full pulse bandwidth predicts conversion efficiencies of about 7% for transform-limited Gaussian pulse bandwidths of 16 nm for mirrors with 45 layers, which exceed those expected from periodic designs. Stability against film thickness fluctuations expected from the deposition …

Annual Faculty Research Symposium 2022, Oakwood University

Proceedings

No abstract provided.

Examining The Optical Properties Of Monosodium Urate For The Detection Of Gout Using A Magneto-Optical Device (Mod), Victoria Marino

Celebration of Scholarship 2022

The purpose of this research was to quantify the magnetooptical properties of monosodium urate (MSU) crystals that would allow for an easy diagnosis using a magneto-optical device (MOD). Characterization of these magnetic and optical properties was achieved by measuring the transmitted light intensity of a laser shining through a sample of monosodium urate with or without an applied (static) magnetic field. Using our theoretical model under the simplifying assumption that absorption is dominant, we determined that the extinction cross-section is σ𝑥 = 0.0127 cm3 /μg and we determined σ𝑧 using two different relationships which gave two distinctly different values. Due …

Measurement Of Optical Rubidium Clock Frequency Spanning 65 Days, Nathan D. Lemke, Kyle W. Martin, River Beard, Benjamin K. Stuhl, Andrew J. Metcalf, John D. Elgin

Physics and Engineering Faculty Publications

Optical clocks are emerging as next-generation timekeeping devices with technological and scientific use cases. Simplified atomic sources such as vapor cells may offer a straightforward path to field use, but suffer from long-term frequency drifts and environmental sensitivities. Here, we measure a laboratory optical clock based on warm rubidium atoms and find low levels of drift on the month-long timescale. We observe and quantify helium contamination inside the glass vapor cell by gradually removing the helium via a vacuum apparatus. We quantify a drift rate of 4 x 10^-15, a 10 day Allan deviation less than 5 x …

Electron-Positron Annihilation Lifetime Spectroscopy Of Mgo And Aluminum-Doped Mgo, Elise Liebow

Honors Theses

Radiation is a form of energy that can damage materials at an atomic level. This has implications for the mobility of radioactive waste through containment materials. We are characterizing atomic defects in materials by using Electron-Positron Annihilation Lifetime Spectroscopy (EPALS). When an electron and positron come into contact with each other, they annihilate and release two antiparallel 511-keV gamma rays. In a pristine crystalline sample, positrons can easily annihilate with electrons, but in a sample with vacancies/defects in the crystal structure, positrons take longer to annihilate. Therefore, the more vacancies in a sample, the longer the average lifetime of a …

Characterization Of Environmental Conditioning Of Lithium Hydride Using Spectroscopy And Machine Learning, Ryan E. Pinson

Theses and Dissertations

Lithium compounds such as lithium hydride (LiH) and anhydrous lithium hydroxide (LiOH) have various applications in industry but are highly reactive when exposed to moisture and CO₂. These reactions create new molecular forms, including compounds such as lithium oxide (Li₂O), lithium hydroxide monohydrate (LiOH ·H₂O), and lithium carbonate (Li₂CO₃). These new compounds degrade the effectiveness in applications using these compounds. The negative effects induced by new lithium compounds creates a need for the ability to characterize the in-growth of such compounds. To study these in-growths, this work will present environmental …

Calculated Charge State Distributions And Anisotropies Following The Β-Decay Of 6he, Eva E. Sculhoff

Electronic Theses and Dissertations

According to the standard model the beta-decay of 6He is a pure Gamow-Teller transition. The aim of this thesis is to provide theoretical support in the search for new physics beyond the standard model by examining the angular distribution of beta particles following decay. The simple structure of 6He, along with its ability to under go beta-decay into 6Li+ makes it an ideal candidate for studying the weak force. Due to the sudden increase in nuclear charge from Z = 2 to Z = 3, and the recoil momentum of the daughter nucleus resulting from the emitted leptons, this decay …

Cu 2+ And Cu 3+ Acceptors In Β-Ga 2 O 3 Crystals: A Magnetic Resonance And Optical Absorption Study, Timothy D. Gustafson, Nancy C. Giles, Brian C. Holloway, Christopher A. Lenyk, J. Jesenovec, J. S. Mccloy, M. D. Mccluskey, Larry E. Halliburton

Faculty Publications

Electron paramagnetic resonance (EPR) and optical absorption are used to characterize Cu²⁺ (3d⁹) and Cu³⁺ (3d⁸) ions in Cu-doped β-Ga₂O₃. These Cu ions are singly ionized acceptors and neutral acceptors, respectively (in semiconductor notation, they are Cu⁻ and Cu⁰ acceptors). Two distinct Cu²⁺ EPR spectra are observed in the as-grown crystals. We refer to them as Cu²⁺(A) and Cu²⁺(B). Spin-Hamiltonian parameters (a g matrix and a ^63,65Cu hyperfine matrix) are obtained from the angular dependence of each spectrum. Additional electron-nuclear double resonance …

Atomistic Simulation Of Na+ And Cl- Ions Binding Mechanisms To Tobermorite 14Å As A Model For Alkali Activated Cements, Ahmed Abdelkawy

Theses and Dissertations

The production of ordinary Portland cement (OPC) is responsible for ~8% of all man-made CO2 emissions. Unfortunately, due to the continuous increase in the number of construction projects, and since virtually all projects depend on hardened cement from the hydration of OPC as the main binding material, the production of OPC is not expected to decrease. Alkali-activated cement produced from the alkaline activation of byproducts of industries, such as iron and coal industries, or processed clays represents a potential substitute for OPC. However, the interaction of the reaction products of AAC with corrosive ions from the environment, such as Cl-, …

Development Of Advanced Machine Learning Models For Analysis Of Plutonium Surrogate Optical Emission Spectra, Ashwin P. Rao, Phillip R. Jenkins, John D. Auxier Ii, Michael B. Shattan, Anil Patnaik

Faculty Publications

This work investigates and applies machine learning paradigms seldom seen in analytical spectroscopy for quantification of gallium in cerium matrices via processing of laser-plasma spectra. Ensemble regressions, support vector machine regressions, Gaussian kernel regressions, and artificial neural network techniques are trained and tested on cerium-gallium pellet spectra. A thorough hyperparameter optimization experiment is conducted initially to determine the best design features for each model. The optimized models are evaluated for sensitivity and precision using the limit of detection (LoD) and root mean-squared error of prediction (RMSEP) metrics, respectively. Gaussian kernel regression yields the superlative predictive model with an RMSEP of …

Electronic Structure Theory, Electronic Friction, And Berry Curvature: An Important Frontier Between Chemistry And Physics, Hung-Hsuan Teh

Publicly Accessible Penn Dissertations

Nonadiabatic dynamics play an important role within electron transfer processes, excitation energy transfer events, the linear/nonlinear spectroscopy of molecular open quantum systems, and molecular junction quantum transport. All of the phenomena listed above can involve multiple electronic states, and the transfer rates between such states can be significantly enhanced or suppressed by including the dynamics of the nuclear degrees of freedom. In order to simulate the relevant nonadiabatic dynamics, a precise and computationally feasible electronic structure theory is necessary. Most importantly, the theory has to be simple enough so that analytic gradients and derivative couplings, which are fundamental building blocks …

What Happens When Transition Metal Trichalcogenides Are Interfaced With Gold?, Archit Dhingra, Dmitri E. Nikonov, Alexey Lipatov, Alexander Sinitskii, Peter Dowben

Peter Dowben Publications

Transition metal trichalcogenides (TMTs) are two-dimensional (2D) systems with quasi-one-dimensional (quasi-1D) chains. These 2D materials are less susceptible to undesirable edge defects, which enhances their promise for low-dimensional optical and electronic device applications. However, so far, the performance of 2D devices based on TMTs has been hampered by contact-related issues. Therefore, in this review, a diligent effort has been made to both elucidate and summarize the interfacial interactions between gold and various TMTs, namely, In₄Se₃, TiS₃, ZrS₃, HfS₃, and HfSe₃. X-ray photoemission spectroscopy data, supported by the results …

The Hitran2020 Molecular Spectroscopic Database, I. E. Gordon, L. S. Rothman, R. J. Hargreaves, R. Hashemi, E. V. Karlovets, F. M. Skinner, E. K. Conway, C. Hill, R. V. Kochanov, Y. Tan, P. Wcisło, A.A. Finenko, K. Nelson, P. F. Bernath, M. Birk, V. Boudon, A. Campargue, K. V. Chance, A. Coustenis, B. J. Drouin, J.-M. Flaud, R. R. Gamache, J. T. Hodges, D. Jacquemart, E. J. Mlawer, A. V. Nikitin, V.I. Perevalov, M. Rotger, J. Tennyson, G. C. Toon, H. Tran, V. G. Tyuterev, E. M. Adkins, A. Baker, A. Barbe, E. Canè, A. G. Császár, A. Dudaryonok, O. Egorov, A. J. Fleisher, H. Fleurbaey, A. Foltynowicz, T. Furtenbacher, J. J. Harrison, J.M. Hartmann, V.- M. Horneman, X. Huang, T. Karman, J. Karns, S. Kassi, I. Kleiner, V. Kofman, F. Kwabia-Tchana, N.N. Lavrentieva, T. J. Lee, D. A. Long, A. A. Lukashevskaya, O. M. Lyulin, V. Yu Makhnev, W. Matt, S. T. Massie, M. Melosso, S. N. Mikhailenko, D. Mondelain, H.S.P. Müller, O. V. Naumenko, A. Perrin, O. L. Polyansky, E. Raddaoui, P. L. Raston, Z. D. Reed, M. Rey, C. Richard, R. Tóbiás, I. Sadiek, D. W. Schwenke, E. Starikova, K. Sung, F. Tamassia, S. A. Tashkun, J. Vander Auwera, I.A. Vasilenko, A.A. Vigasin, G.L. Villanueva, B. Vispoel, G. Wagner, A. Yachmenev, S. N. Yurchenko

Chemistry & Biochemistry Faculty Publications

The HITRAN database is a compilation of molecular spectroscopic parameters. It was established in the early 1970s and is used by various computer codes to predict and simulate the transmission and emission of light in gaseous media (with an emphasis on terrestrial and planetary atmospheres). The HITRAN compilation is composed of five major components: the line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, experimental infrared absorption cross-sections (for molecules where it is not yet feasible for representation in a line-by-line form), collision-induced absorption data, aerosol indices of refraction, and general tables (including partition sums) that apply globally to the data. …