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Fluid Dynamics Of Interacting Particles: Bouncing Droplets And Colloid-Polymer Mixtures, Lauren Barnes

Dissertations

Interacting particles are a common theme across various physical systems, particularly on the atomic and sub-atomic scales. While these particles cannot be seen with the human eye, insight into such systems can be gained by observing macroscopic systems whose physical behavior is similar. This dissertation consists of three different chapters, each presenting a different problem related to interacting particles, as follows:

Chapter 1 explores chaotic trajectories of a droplet bouncing on the surface of a vertically vibrating fluid bath, with a simple harmonic force acting on the droplet. The bouncing droplet system has attracted recent interest because it exhibits behaviors …

Boundary Integral Equation Methods For Superhydrophobic Flow And Integrated Photonics, Kosuke Sugita

Dissertations

This dissertation presents fast integral equation methods (FIEMs) for solving two important problems encountered in practical engineering applications.

The first problem involves the mixed boundary value problem in two-dimensional Stokes flow, which appears commonly in computational fluid mechanics. This problem is particularly relevant to the design of microfluidic devices, especially those involving superhydrophobic (SH) flows over surfaces made of composite solid materials with alternating solid portions, grooves, or air pockets, leading to enhanced slip.

The second problem addresses waveguide devices in two dimensions, governed by the Helmholtz equation with Dirichlet conditions imposed on the boundary. This problem serves as a …

Variable Resolution Smoothed Particle Hydrodynamics Schemes For 2-D And 3-D Viscous Flows, Francesco Ricci

Dissertations

Smoothed Particle Hydrodynamics (SPH) is a Lagrangian particle-based method for the numerical solution of the partial differential equations that govern the motion of fluids. The main aim of this thesis work is to better enable the applicability of SPH to problems involving multi-scale fluid dynamics. In the first part of the thesis, the capability of the SPH method to simulate three-dimensional isotropic turbulence is investigated with a detailed comparison of Lagrangian and Eulerian SPH formulations. The main reason for this first investigation is to provide an assessment of the error introduced by the particle disorder on the SPH discrete operators …

Supporting Neurodivergent Talent: Adhd, Autism, And Dyslexia In Physics And Space Sciences, Niescja E. Turner, Heather Haynes Smith

Physics and Astronomy Faculty Research

Diversity, equity, inclusion, and belonging efforts must include disability and neurodivergence. While there is a long history of famous scientists being identified or speculatively indicated to be neurodivergent, identification on an individual basis has been limited until fairly recently. Definitions have changed and broadened, and people are being identified or are identifying themselves as neurodivergent and are learning about their paths and their brains in a way that was unavailable to people two decades ago. In the contemporary physics or space science classroom or workplace, we have both a responsibility to include and support our neurodivergent learners and scientists, as …

First Measurement Of The Nuclear-Recoil Ionization Yield In Silicon At 100 Ev, M. F. Albakry, I. Alkhatib, D. Alonso, D. W. P. Amaral, T. Aralis, T. Aramaki, I. J. Arnquist, I. Ataee Langroudy, E. Azadbakht, S. Banik, C. Bathurst, R. Bhattacharyya, P. L. Brink, R. Bunker, B. Cabrera, R. Calkins, R. A. Cameron, C. Cartaro, D. G. Cerdeño, Y. -Y. Chang, M. Chaudhuri, R. Chen, N. Chott, J. Cooley, H. Coombes, J. Corbett, P. Cushman, S. Das, F. De Brienne, M. Rios, S. Dharani, M. L. Di Vacri, M. D. Diamond, M. Elwan, E. Fascione, E. Figueroa-Feliciano, C. W. Fink, K. Fouts, M. Fritts, G. Gerbier, R. Germound, M. Ghaith, S. R. Golwala, J. Hall, S. A.S. Harms, N. Hassan, B. A. Hines, Z. Hong, E. W. Hoppe, L. Hsu, M. E. Huber, V. Iyer, V. K. S. Kashyap, M. H. Kelsey, A. Kubik, N. A. Kurinsky, M. Lee, M. Litke, J. Liu, Y. Lui, B. Loer, E. Lopez Asamar, P. Lukens, D. B. Macfarlane, R. Mahapatra, N. Mast, A. J. Mayer, H. Meyer Zu Theenhausen, É. Michaud, E. Michielin, N. Mirabolfathi, B. Mohanty, B. Nebolsky, J. Nelson, H. Neog, V. Novati, J. L. Orrell, M. D. Osborne, S. M. Oser, W. A. Page, L. Pandey, S. Pandey, R. Partridge, D. S. Pedreros, L. Perna, R. Podviianiuk, F. Ponce, S. Poudel, A. Pradeep, M. Pyle, W. Rau, E. Reid, R. Ren, T. Reynolds, E. Tanner, A. Roberts, A. E. Robinson, T. Saab, D. Sadek, B. Sadoulet, S. P. Sahoo, I. Saikia, J. Sander, A. Sattari, B. Schmidt, R. W. Schnee, S. Scorza, B. Serfass, S. S. Poudel, D. J. Sincavage, P. Sinervo, Z. Speaks, J. Street, H. Sun, G. D. Terry, F. K. Thasrawala, D. Toback, R. Underwood, S. Verma, A. N. Villano, B. Von Krosigk, S. L. Watkins, O. Wen, Z. Williams, M. J. Wilson, J. Winchell, K. Wykoff, S. Yellin, Betty A. Young, T. C. Yu, B. Zatschler, S. Zatschler, A. Zaytsev, A. Zeolla, E. Zhang, L. Zheng, Y. Zheng, A. Zuniga, P. An, P. S. Barbeau, S. C. Hedges, L. Li, J. Runge

Physics

We measured the nuclear-recoil ionization yield in silicon with a cryogenic phonon-sensitive gram-scale detector. Neutrons from a monoenergetic beam scatter off of the silicon nuclei at angles corresponding to energy depositions from 4 keV down to 100 eV, the lowest energy probed so far. The results show no sign of an ionization production threshold above 100 eV. These results call for further investigation of the ionization yield theory and a comprehensive determination of the detector response function at energies below the keV scale.

The Importance Of Recruitment And Retention In Heliophysics: It's Not Just A Pipeline Problem, A. J. Halford, C. M. Bard, A. G. Burrell, R. M. Mcgranaghan, L. B. Wilson Iii, M. Jones Jr, C. Dong, L. Wang, T. I. Pulkkinen, Niescja E. Turner, M. W. Liemohn, J. Klenzing

Physics and Astronomy Faculty Research

A major obstacle in cultivating a robust Heliophysics (and broader scientific) community is the lack of diversity throughout science, technology, engineering, and mathematics (STEM) fields. For many years, this has been understood as a “leaky pipeline” analogy, in which predominately minority students initially interested in STEM gradually fall (or are pushed) out of the field on their way to a scientific research position. However, this ignores critical structural and policy issues which drive even later career Ph.D.s out of a career in Heliophysics. We identify here several systemic problems that inhibit many from participating fully in the Heliophysics community, including …

A Compendious Review Of Majorization-Based Resource Theories: Quantum Information And Quantum Thermodynamics, Gökhan Torun, Onur Pusuluk, Özgür Esat Müstecaplioğlu

Turkish Journal of Physics

The field of quantum resource theory (QRT) has emerged as an invaluable framework for the examination of small and strongly correlated quantum systems, surpassing the boundaries imposed by traditional statistical treatments. The fundamental objective of general QRTs is to characterize these systems by precisely quantifying the level of control attainable to an experimenter. In this review article, we refrain from providing an exhaustive summary of the extensive literature on QRT. Rather, our focus centers on a specific subliterature founded upon the theory of majorization. The primary aim is to augment our comprehension of genuine quantum phenomena manifested across diverse technological …

Development And Benchmark Of A 1d3v Electrostatic Pic/Mcc Numerical Code For Gas Discharge Simulations, İbrahi̇m Arda, İsmai̇l Rafatov

Turkish Journal of Physics

Gas discharge plasmas are low-temperature nonequilibrium plasmas that have a wide range of scientific and technological applications. The particle-in-cell/Monte Carlo collision (PIC/MCC) method is a reliable approach for numerical analyses and simulations of such plasmas. In this study, we first provide a detailed description of the basics of this method. We then verify the programme code that we developed in Fortran by benchmarking the code against a widely referred reference study simulating a radiofrequency capacitively coupled plasma (RFCCP) in helium for various discharge conditions. We show that the results of the present study are in good agreement with that of …

An Improved Source Of Spin-Polarized Electrons Based On Spin Exchange In Optically Pumped Rubidium Vapor, K. J. Ahrendsen, Kenneth Wayne Trantham, D. Tupa, T. J. Gay

Department of Physics and Astronomy: Faculty Publications

We have improved a polarized electron source in which unpolarized electrons undergo collisions with a mixture of buffer gas molecules and optically spin-polarized Rb atoms. With a nitrogen buffer gas, the source reliably provides spin polarization between 15% and 25% with beam currents >4 μA. Vacuum pump upgrades mitigate problems caused by denatured diffusion pump oil, leading to longer run times. A new differential pumping scheme allows the use of higher buffer gas pressures up to 800 mTorr. With a new optics layout, the Rb polarization is continuously monitored by a probe laser and improved pump laser power provides more …

Search For Magnetoelectric Monopole Response In Cr2O3 Powder, Syed Qamar Abbas Shah, Ather Mahmood, Arun Parthasarathy, Christian H. Binek

Department of Physics and Astronomy: Faculty Publications

Powder samples have been suggested as a pathway to fabricate isotropic magnetoelectric (ME) materials which effectively only have a pseudoscalar or monopole ME response. We demonstrate that random distribution of ME grains alone does not warrant isotropic ME response because the activation of a nonvanishing ME response requires a ME field cooling protocol which tends to induce preferred axes.We investigate the evolution of ME susceptibility in powder chromia samples for various ME field cooling protocols both theoretically and experimentally. In particular, we work out the theoretical expressions for ME susceptibility for powder chromia in the framework of statistical mechanics where …

Hidden Little Monsters: Spectroscopic Identification Of Low-Mass, Broad-Line Agns At Z > 5 With Ceers, Dale D. Kocevski, Masafusa Onoue, Kohei Inayoshi, Jonathan R. Trump, Pablo Arrabal Haro, Andrea Grazian, Mark Dickinson, Steven L. Finkelstein, Jeyhan S. Kartaltepe, Michaela Hirschmann, James Aird, Benne W. Holwerda, Seiji Fujimoto, Stéphanie Juneau, Ricardo O. Amorín, Bren E. Backhaus, Micaela B. Bagley, Guillermo Barro, Eric F. Bell, Laura Bisigello, Antonello Calabrò, Nikko J. Cleri

Pacific Faculty Work

We report on the discovery of two low-luminosity, broad-line active galactic nuclei (AGNs) at z > 5 identified using JWST NIRSpec spectroscopy from the Cosmic Evolution Early Release Science (CEERS) survey. We detect broad Hα emission in the spectra of both sources, with FWHM of 2060 ± 290 km s⁻¹ and 1800 ± 200 km s⁻¹, resulting in virial black hole (BH) masses that are 1-2 dex below those of existing samples of luminous quasars at z > 5. The first source, CEERS 2782 at z = 5.242, is 2-3 dex fainter than known quasars at similar redshifts and …

Hellings And Downs Correlation Of An Arbitrary Set Of Pulsars, Bruce Allen, Joseph D. Romano

Physics & Astronomy Faculty Publications

Pulsar timing arrays (PTAs) detect gravitational waves (GWs) via the correlations they induce in the arrival times of pulses from different pulsars. We assume that the GWs are described by a Gaussian ensemble, which models the confusion noise produced by expected PTA sources. The mean correlation h2μu(γ) as a function of the angle γ between the directions to two pulsars was predicted by Hellings and Downs in 1983. The variance σ2tot(γ) in this correlation was recently calculated [B. Allen, Variance of the Hellings-Downs correlation, Phys. Rev. D 107, 043018 (2023)] for a single noise-free pulsar pair at angle γ, …

Hellings And Downs Correlation Of An Arbitrary Set Of Pulsars, Bruce Allen, Joseph D. Romano

Physics & Astronomy Faculty Publications

Pulsar timing arrays (PTAs) detect gravitational waves (GWs) via the correlations they induce in the arrival times of pulses from different pulsars. We assume that the GWs are described by a Gaussian ensemble, which models the confusion noise produced by expected PTA sources. The mean correlation h2μu(γ) as a function of the angle γ between the directions to two pulsars was predicted by Hellings and Downs in 1983. The variance σ2tot(γ) in this correlation was recently calculated [B. Allen, Variance of the Hellings-Downs correlation, Phys. Rev. D 107, 043018 (2023)] for a single noise-free pulsar pair at angle γ, …

A Search For Decays Of The Higgs Boson To Invisible Particles In Events With A Top-Antitop Quark Pair Or A Vector Boson In Proton-Proton Collisions At √S = 13 Tev, Armen R. Tumasyan

Department of Physics and Astronomy: Faculty Publications

The first search for nonresonant production of Higgs boson pairs (HH) with one H decaying into four leptons and the other into a pair of b quarks is presented, using proton-proton collisions recorded at a center-of-mass energy of √s = 13 TeV by the CMS experiment. The analyzed data correspond to an integrated luminosity of 138 fb⁻¹. A 95% confidence level upper limit of 32.4 is set on the signal strength modifier μ, defined as the ratio of the observed HH production rate in the HH → ZZ*bb → 4ℓbb decay channel to the standard model …

Anharmonicity And Deuteration In The Ir Absorption And Emission Spectra Of Phenylacetylene, Vincent J. Esposito, Pierro Ferrari, Wybren Jan Buma, Christiaan Boersma, Cameron J. Mackie, Alessandra Candian, Ryan C. Fortenberry, Alexander G. G. M. Tielens

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Anharmonic cascade emission simulations, herein evinced by full reproduction and deep insights into recent emission spectroscopy experiments of phenylacetylene, are integral to the future successful analysis of JWST observational spectra. Experimental infrared absorption experiments conducted in this study reveal a complex spectrum dominated by quantum effects that are uncovered by anharmonic computational analysis. From this work, it becomes clear that phenylacetylene exhibits strong resonance coupling between fundamental and two-quanta combination modes as well as giving indication for coupling with higher-order, three-quanta combination bands. This study benchmarks the development of advanced computational methods that will be extended to larger systems of …

A Sensitivity Study Of Triboson Production Processes To Dimension-6 Eft Operators At The Lhc, R. Bellan, S. Bhattacharya, G. Boldrini, F. Cetorelli, P. Govoni, A. Massironi, A. Mecca, C. Tarricone, A. Vagnerini

Department of Physics and Astronomy: Faculty Publications

We present the first parton-level study of anomalous effects in triboson production in both fully and semi-leptonic channels in proton-proton collisions at 13TeV at the Large Hadron Collider (LHC). The sensitivity to anomalies induced by a minimal set of bosonic dimension-6 operators from the Warsaw basis is evaluated with specific analyses for each final state. A likelihood-based strategy is employed to assess the most sensitive kinematic observables per channel, where the contribution of Effective Field Theory operators is parameterized at either the linear or quadratic level. The impact of the mutual interference terms of pairs of operators on the sensitivity …

Finite Charges From The Bulk Action, Robert Mcnees, Céline Zwikel

Physics: Faculty Publications and Other Works

Constructing charges in the covariant phase space formalism often leads to formally divergent expressions, even when the fields satisfy physically acceptable fall-off conditions. These expressions can be rendered finite by corner ambiguities in the definition of the presymplectic potential, which in some cases may be motivated by arguments involving boundary Lagrangians. We show that the necessary corner terms are already present in the variation of the bulk action and can be extracted in a straightforward way. Once these corner terms are included in the presymplectic potential, charges derived from an associated codimension-2 form are automatically finite. We illustrate the procedure …

Online Data Transmission Reduction Scheme For Energy Conservation In Wireless Video Sensor Networks, Iman Kadhum Abbood, Ali Kadhum Idrees

Karbala International Journal of Modern Science

Wireless Video Sensor Networks (WVSNs) are networks of low-cost, low-power camera sensor nodes. These nodes communicate locally and process information to meet an application's goal. WVSNs are extensively used in diverse monitoring applications, such as security, military, industrial, medical, and environmental monitoring. However, the transmission of large amounts of data collected by video sensor nodes in WVSNs poses challenges in terms of energy consumption, bandwidth usage, and network congestion. Reducing energy for processing and transmitting data in WVSNs is difficult due to the huge amount of sensed data in real-time. To address this issue, this paper proposes an Online Data …

Biogenesis Synthesis Of Zno Nps: Its Adsorption And Photocatalytic Activity For Removal Of Acid Black 210 Dye, Zahraa A. Najm, Mohammed A. Atiya, Ahmed K. Hassan

Karbala International Journal of Modern Science

This study investigated the treatment of textile wastewater contaminated with Acid Black 210 dye (AB210) using zinc oxide nanoparticles (ZnO NPs) through adsorption and photocatalytic techniques. ZnO NPs were synthesized using a green synthesis process involving eucalyptus leaves as reducing and capping agents. The synthesized ZnO NPs were characterized using UV-Vis spectroscopy, SEM, EDAX, XRD, BET, Zeta potential, and FTIR techniques. The BET analysis revealed a specific surface area and total pore volume of 26.318 m²/g. SEM images confirmed the crystalline and spherical nature of the particles, with a particle size of 73.4 nm. A photoreactor was designed …

Initial Experience With An Electron Flash Research Extension (Flex) For The Clinac System, Kyuhak Oh, Kyle J. Gallagher, Megan Hyun, Diane Schott, Sarah Wisnoskie, Yu Lei, Samuel Hendley, Jeffrey Wong, Shuo Wang, Brendan Graff, Christopher Jenkins, Frank Rutar, Md Ahmed, Joshua Mcneur, Jeffrey Taylor, Marty Schmidt, Lasitha Senadheera, Wendy Smith, Subodh M. Lele, Ran Dai, Dong Jianghu (James), Y Yan, Su-Min Zhou

Department of Physics and Astronomy: Faculty Publications

Purpose: Radiotherapy delivered at ultra-high-dose-rates (≥40 Gy/s), that is, FLASH, has the potential to effectively widen the therapeutic window and considerably improve the care of cancer patients. The underlying mechanism of the FLASH effect is not well understood, and commercial systems capable of delivering such dose rates are scarce. The purpose of this study was to perform the initial acceptance and commissioning tests of an electron FLASH research product for preclinical studies.

Methods: A linear accelerator (Clinac 23EX) was modified to include a nonclinical FLASH research extension (the Clinac-FLEX system) by Varian, a Siemens Healthineers company (Palo Alto, …

Syllabus For Computational Physics (Phys 39907), Mark D. Shattuck

Open Educational Resources

Syllabus for City College of New York Computational Physics course.

Ultrasound Assisted Comparative Study Of Fucolam And So-Dium Alginate And Impact On Their Physiochemical Proper-Ties Using Box-Behnken Design, Uday Bagale, Ammar Kadi, Artem Malinin, Varisha Anjum, Irina Potoroko

Karbala International Journal of Modern Science

The article discusses about the possibility of comparing the impact of ultrasonic treatment on fucolam and sodium algi-nate. The purpose was to study the effect of micronization on the sulfated heteropolysaccharide fucolam, analyzing its dispersed state and accessibility by reducing its molecular weight and increasing antioxidant activity. The optimization of the micronization process was carried out using the Box-Behnken Design (BBD) method, with a sonication time ranging from 15 to 45 min, power ranging from 50 to 100 W/cm2, and temperature between 30 °C and 40 °C. The fixed lower fucolam concentration was 0.1%. The results illustrated that sonochemical treatment …

Deep Learning-Based Cad System For Predicting The Covid-19 X-Ray Images, Aqeel R. Talib, Hana’ M. Ali

Karbala International Journal of Modern Science

According to World Health Organization data, Coronavirus (COVID-19) has infected about 660, 378, 145 patients around the world. It is nonetheless difficult for physicians to detect COVID-19 infections out of CT or X-ray radiographs. Thus, several computer-aided diagnosis (CAD) systems based on deep learning and radiographs were developed to detect COVID-19 infections. However, the majority of approaches considered small datasets, which is ineligible to provide diverse COVID-19 radiographs. This work utilizes a massive number of X-ray radiographs, and compared standard CNN, DenseNet-121, and GoogLeNet for isolating COVID-19 infections out from normal and other pneumonia radiographs. The dataset in this work …

Multi-Agent Deep Reinforcement Learning For Radiation Localization, Benjamin Scott Totten

Dissertations and Theses

For the safety of both equipment and human life, it is important to identify the location of orphaned radioactive material as quickly and accurately as possible. There are many factors that make radiation localization a challenging task, such as low gamma radiation signal strength and the need to search in unknown environments without prior information. The inverse-square relationship between the intensity of radiation and the source location, the probabilistic nature of nuclear decay and gamma ray detection, and the pervasive presence of naturally occurring environmental radiation complicates localization tasks. The presence of obstructions in complex environments can further attenuate the …

Nalidarturbopauseshear, Titus Yuan

Browse all Datasets

The USU Na lidar has been upgraded to be able to measure temperature and winds in the lower thermosphere up to ~ 115 km routinely. The new capability, coupled with the existing nightglow instruments at USU, enables the investigation of the extreme large wind and shears in this region and their correlation to the atmospheric gravity waves activities in the upper mesosphere.

A Simple Method For Determining Shallow Charge Distributions In Dielectrics Via Pulsed Electroacoustic Measurements, Zachary Gibson, J. R. Dennison

Journal Articles

The understanding of charge dynamics in dielectric materials is paramount in mitigating electrostatic discharge events for spacecraft. The most critical spacecraft charging events are found to result from incident electrons in the energy range of 10 keV to 50 keV. The charge embedded in dielectric materials in this energy range are deposited a distance into the material on the order of a few to tens of microns. One way to measure and understand the deposited charge is via pulsed electroacoustic measurements (PEA). However, the typical PEA spatial resolution of ~ 10 μm is not sufficient to resolve or discern charge …

A Search For Relativistic Ejecta In A Sample Of Ztf Broad-Lined Type Ic Supernovae, Alessandra Corsi, Anna Y.Q. Ho, S. Bradley Cenko, Shrinivas R. Kulkarni, Shreya Anand, Sheng Yang, Jesper Sollerman, Gokul P. Srinivasaragavan, Conor M.B. Omand, Arvind Balasubramanian, Dale A. Frail, Christoffer Fremling, Daniel A. Perley, Yuhan Yao, Aishwarya S. Dahiwale, Kishalay De, Alison Dugas, Matthew Hankins, Jacob Jencson, Mansi M. Kasliwal, Anastasios Tzanidakis, Eric C. Bellm, Russ R. Laher, Frank J. Masci, Josiah N. Purdum, Nicolas Regnault

Michigan Tech Publications

The dividing line between gamma-ray bursts (GRBs) and ordinary stripped-envelope core-collapse supernovae (SNe) is yet to be fully understood. Observationally mapping the variety of ejecta outcomes (ultrarelativistic, mildly relativistic, or nonrelativistic) in SNe of Type Ic with broad lines (Ic - BL) can provide a key test to stellar explosion models. However, this requires large samples of the rare SN Ic - BL events with follow-up observations in the radio, where fast ejecta can be probed largely free of geometry and viewing angle effects. Here, we present the results of a radio (and X-ray) follow-up campaign of 16 SNe Ic …

Magnetic Nanodoping: Atomic Control Of Spin States In Cobalt Doped Silver Clusters, Vicente Zamudio-Bayer, Konstantin Hirsch, Lei Ma, Kobe De Knijf, X. S. Xu, Arkadiusz Ławicki, Akira Terasaki, Piero Ferrari, Bernd Von Issendorff, Peter Lievens, Walt A. De Heer, J. Tobias Lau, Ewald Janssens

Department of Physics and Astronomy: Faculty Publications

The interaction of magnetic dopants with delocalized electron states can result in interesting many-body physics. Here, the magnetic properties of neutral and charged finite silver metal host clusters with a magnetic cobalt atom impurity were investigated experimentally by exploiting the complementary methods of Stern- Gerlach molecular beam deflection and x-ray magnetic circular dichroism spectroscopy and are accompanied by density functional theory calculations and charge transfer multiplet simulations. The influence of the number of valence electrons and the consequences of impurity encapsulation were addressed in free size-selected, singly cobalt-doped silver clusters CoAg^0,_n+ (n = 2–15). Encapsulation of the …

Theoretical Framework Of Exchange Coupled Tripartite Spin Systems With Magnetic Anisotropy And Predictions Of Spin And Electronic Transport Properties For Their Use In Quantum Architectures, Eric Switzer

Electronic Theses and Dissertations, 2020-2023

There has been significant interest in spin systems involving two or more coupled spins as a single logical qubit, particularly for scalable quantum computing architectures. Recent realizations include the so-called singlet-triplet qubits and coupled magnetic molecules. An important class of coupled-spin systems, the three-spin paradigm for spin greater than 1/2, has not yet been fully realized in scalable qubit architectures. In this thesis, I develop the theoretical framework to investigate a class of tripartite spin models for realistic systems. First, I model a spin 1/2 particle (e.g., an electron) and two spin 1 particles (in a dimer arrangement) coupled with …

Theoretical Analysis Of Charge Conduction And Rectification In Self-Assembled-Monolayers In Molecular Junctions, Francis Adoah

Electronic Theses and Dissertations, 2020-2023

As electrical devices shrink to the atomic scale, it is expected that Moore's law will soon be obsolete for semiconductor devices. In 1974, Avriam and Ratner predicted that organic devices could replace semiconductor technology, leading to extensive research on molecular-based organic devices. This dissertation delves into the theoretical frameworks used to examine the transport in molecular junctions and aims to enhance our comprehension of charge transport and conduction properties. The studies presented in this thesis illustrates that a molecule's alteration by just a single atom can change it from an insulator to a conductor, and also that, by fine-tuning the …