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Characterization and Control of Spatial Correlations in Entangled Twin Beams
Get PDFOur understanding and ability to manipulate quantum correlations in non-classical states of light
will be a determining factor in realizing the next generation of quantum technologies. Over the
last several decades, we witnessed the wide-scale use of sensing and communication technologies,
such as RADAR/LiDAR, radio, and fiber-optics telecommunications, that were based on classical
conceptions of electromagnetic fields. Harnessing the power of the counter-intuitive phenomenon of
quantum superposition and entanglement, quantum theory promises a transformative leap in capabilities
that lies beyond such classical approaches. The early success of quantum secure communication,
quantum computers, advanced gravitational-wave detectors, and quantum random number
generators offer a glimpse into the immense potential offered by quantum mechanics. This dissertation
investigates the manipulation of quantum correlations in light, particularly focusing on the
spatial degrees of freedom, to propel the development of next-generation quantum technologies.
Quantum states of light, known as twin beams, intrinsically linked through quantum correlations,
form the cornerstone of this exploration. These bipartite entangled beams of light are at the heart of
several quantum sensing applications and are natural candidates to encode and exchange quantum
information. Their generation via the nonlinear parametric process of four-wave mixing leads to
temporal (energy conservation) and spatial (momentum conservation) correlations in the quantum
regime. Notably, the conservation of transverse momentum in the fields during the process implies
that the spatial properties of the input photons determine the distribution of spatial correlations in
the generated entangled photons, thus providing a practical way to engineer the correlated spatial
modes. After characterizing the entanglement within the spatial as well as spatio-temporal degrees
of freedom of the twin beams via a direct imaging technique, this dissertation delves into the
extensive engineering of spatial correlations of the fields generated through four-wave mixing.
Our approach of using a deliberately phase-structured input field to drive the four-wave mixing
leads to the creation of spatially structured quantum states. The degree of control demonstrated
via the phase manipulation implies that this approach can be tailored to the specific requirements
of quantum sensing and imaging applications. The abundance of spatial modes in the multimode
twin beams that utilize the vastness of the Hilbert space associated with spatial modes, coupled
with precise control over their correlations, unlocks possibilities for high-dimensional quantum communication
protocols, leading to ultra-secure and high-capacity quantum teleportation and communication
"Fit for a Picture:" Aestheticizing Southwestern Utah and the Creation of Zion National Park
No full textThe exploration of the monumental landscapes of the trans-Mississippi West in the decades following the Civil War produced a vast archive of imagery detailing the strange new landforms that would not only elucidate the Earth’s geological history but provide the justification for the country to expand westward. The artists and photographers who accompanied these expeditions not only gave visual form to the scientific findings but also fueled public enthusiasm for such explorations in images widely circulated by such popular magazines as Appleton’s, Harper’s Weekly, and The Aldine. Working within the conventions of landscape painting these artists aestheticized these sites, transforming land into scenery, which not only helped the American public to recognize the sometimes newly-acquired lands as American sites by inviting viewers to imaginatively inhabit the scene but also fueled such an enthusiasm for conserving such scenery leading to the establishment of the first national parks. When the National Park Service Act passed in 1916, the conservation of scenery was of the utmost importance to develop these sites into tourist destinations. Combined with the histories, place names, and visitors who projected cultural values onto the land, these aesthetic treatments of a site helped form landmarks and narrative traditions that would teach potential tourists how to look at and interact with the land itself. For the Virgin River Valley in southwestern Utah, which would eventually become Zion National Park in 1919, this process of aestheticizing the land and imbuing it with cultural referents began with artists from the Church of Latter-Day Saints in 1870, with photographer Charles Savage, who was the first to bring images of the canyon to the public through his photography studio in Salt Lake City. He and his Church of Latter-Day Saints (LDS) colleagues, easel painters George Ottinger and Alfred Lambourne, interpreted the canyon with the religious fervor of both their LDS community that settled Utah Territory and wider romantic conceits about the American West’s beauty as proof of the young republic’s desire to expand its influence. Soon thereafter came the United States geological survey of the Colorado River, headed by John Wesley Powell and accompanied by photographers and artists, such as James Fennemore, John K. Hillers, and Thomas Moran. Their pictures would go on to become some of the most popular and widely circulated images of Zion Canyon in the last quarter of the nineteenth century through the commercial sale of stereographs and prints as well as published illustrations in popular periodicals. The exhibition of some of these images at World’s Fairs in Philadelphia (1876), Chicago (1893), and St. Louis (1904) further extended the public reach of several Zion Canyon images, particularly those of the UGSG by Jack Hillers. Against the backdrop of the See America First movement in the opening decades of the twentieth century, promotional publications, written by those eager to nurture tourism to Zion Canyon, recalled the earliest images of the gorge not only to establish landmarks but to firmly place the canyon within the scope of uniquely American sites that defined the country’s exceptionalism
Education policy and reform in the state of Oklahoma after 1950 and the achievement gaps of underserved student populations
Get PDFThe educational reform brought about by the U.S. federal government and the state of Oklahoma after 1950 perpetuated an already broken system rather than creating the needed change for all minority student populations across socioeconomic divides and ethnicities. While educational reform has been on the political agenda for every president since the 1960's debate between Kennedy and Nixon; the federal government has failed to positively influence student outcomes, specifically for those minorities of color and of the economically disadvantaged. Local, national, and global reports all point to the mediocracy of America's education system despite spending much more than most industrialized countries on education. The state of Oklahoma, a geographic anomaly, has an interesting educational history with progressive reforms and contradictory policies that have harmed minority student populations. It is here in Oklahoma that my research will find what state reform has done to affect minority students in the past 80 years
The Influence of Social Dominance Orientation on Public Support for Carbon Capture and Storage with the Risk of Induced Seismicity
Get PDFWe present social survey findings regarding the influence of social dominance orientation (SDO) on public support for carbon capture, utilization, and underground storage (CCUS) technologies with the risk of induced seismicity. Using data from a nationally representative survey of 2,188 U.S. adults conducted in Spring 2023, regression analyses are used to examine how SDO shapes attitudes towards CCUS while controlling for demographic factors, political affiliations, and religious beliefs. The findings
reveal a positive correlation between higher SDO scores and support for CCUS, particularly related to SDO-dominance beliefs. Additionally, political ideology, education, income, and religious beliefs emerged as significant predictors of CCUS acceptance, and regional variations in CCUS support and SDO were observed across U.S. Census divisions. These results suggest a complex interplay between psychological, social, and demographic factors in shaping public attitudes towards climate change
mitigation technologies, that warrant further research to provide insights for policymakers and communicators seeking to promote CCUS adoption while addressing potential social and environmental concerns.N
CHINA’S PIONEERING COMPOSER: A STYLISTIC AND PEDAGOGICAL ANALYSIS OF SELECTED SOLO PIANO COMPOSITIONS BY DING SHANDE
No full textDing Shande (1911–1995) was a pivotal figure in 20th century China, pioneering the development of Chinese piano pedagogy, music education, and piano performance. This document aims to analyze a selection of pedagogical solo piano works of Chinese composer, Ding Shande: First Lessons in Piano (1957) and Eight Piano Pieces for Children, op. 28 (1987). Through the comprehensive review of these works, this study reveals Ding Shande’s approach to piano teaching, composition, and music education, underscoring his profound influence on the development of Chinese piano pedagogy and music education in the 20th century. Chapter One includes an overview of the topic, the purpose, need, and limitations of the study, and a review of related literature. Chapter Two provides a biographical overview of Ding Shande’s life and works, including a summary of his important contributions to piano pedagogy, composition, research, and performance. Chapters Three features a pedagogical analysis of Ding Shande’s pioneering composition, First Lessons in Piano, the first Chinese piano method composed for elementary pianists. Chapter Four includes a performance and pedagogical analysis of Ding Shande’s late work, Eight Piano Pieces for Children, op. 28. Stylistic, formal, performance, and pedagogical information will be provided for each work in op. 28. Chapter Five features a brief conclusion and includes suggestions for further study
Thermal Expansion Coefficient Investigations in Oilwell Cements and Various Materials Using a Unique Experimental Setup
Get PDFThe energy demand is increasing around the globe, and while oil and gas continue to play a main part in the energy impact, renewables are taking place as important contributors. In addition to this, the net-zero policy by 2050 developed in the United States is leaning the efforts towards cleaner energies. In that respect, geothermal will play an important function due to the untapped resources and presence around the world. Geothermal, as well as oil and gas operations, comes with different operational challenges, such as depth, which makes subsurface conditions very aggressive with respect to temperature and pressure. Therefore, to successfully perform geothermal operations, the integrity of the well needs to be assured.
Casing and cement play a crucial role in terms of well integrity, as many studies have suggested. Moreover, the elevated temperatures in geothermal operations make thermal properties on these components a parameter of utmost importance, something not widely investigated in comparison with mechanical properties. Thermal expansion is a thermal property with an important impact in the integrity of the wells, which might be jeopardized due to the constant thermal loads effected in such operations. Effects in casing go up to the collapse of the tubular, while cement can suffer from micro-annuli, cracks or debonding.
This investigation focuses on the measurements of the coefficient of linear thermal expansion for oilwell cements, as well as other reference materials and rocks, with novel equipment developed in the Well Integrity Laboratory at The University of Oklahoma. This equipment, which uses an optical shadowing technique, provides faster coefficient of linear thermal expansion calculations in contrast to other equipment or techniques.
More than 300 measurements were performed in this investigation, which includes diverse materials and rocks, are performed not just to corroborate the reliability on the equipment, but also to create a comparison between the coefficient of linear thermal expansions found in diverse literature. The experiments are performed at high temperatures up to 200 ºC (400 ºF), which simulate the extreme temperature conditions encountered in deeper downhole conditions for oil and gas, as well as in geothermal processes. Additionally, characterization of this thermal property is performed for oilwell cement composites, creating a unique database for different mixtures in which different recipes, including neat Class C, G and H cement, as well as other recipes with added additives are comprised. Moreover, other aspects such as cyclic tests or curing times, which go from 14 days to 3 years, are varied.
In conclusion, the results generated by this novel equipment provide reliable coefficient of linear thermal expansion values, when associating them with the values found in different studies. Additionally, the comparison in the coefficient of linear thermal expansion values performed for the different cement composites shows the effects of curing time and cyclic loading for the coefficient in linear thermal expansion on oilwell cements. Several discussions are made based on the experiments conducted in this research
WHY EDUCATION? AN EXAMINATION OF WHY LATINOS/HISPANICS PURSUE A CAREER AS TEACHERS
Get PDFSupported by research on urban education, teacher shortages, and ethnic representation, this qualitative case study seeks to explore the motivations behind Hispanics and/or Latinos pursuing careers in education and the paths they take to achieve this objective. Conducted through semi-structured virtual interviews with ten current educators in the Oklahoma City metro area, the study employs Critical Race Theory and Latino Critical Race Theory to analyze their lived experiences. From these interviews, five key themes emerged: adverse high school experiences, lack of college knowledge, financial obstacles, language barriers, and strong connections with students. These findings illuminate the hurdles encountered by Hispanic and/or Latino individuals in the education field, emphasizing the necessity for systemic support and representation. The insights gleaned from this research provide valuable direction for educational institutions and policymakers, offering strategies to overcome barriers and foster a more inclusive environment. By prioritizing diversity and representation, the goal is to inspire and empower more Hispanics and/or Latinos to pursue careers in education, thereby enhancing the profession and benefiting students and communities alike
Information Theoretic Modeling of Antennas
No full textLinear time-invariant (LTI) electrically small antennas (ESAs) have inherent limitations in their capabilities. Two significant limitations apply to LTI antennas: a lower bound on the antenna Q-factor, which causes a narrow bandwidth limitation; and impedance matching constraints, which restrict the ability to effectively radiate power. To surpass these limitations, recent research has analyzed the use of active antennas with nonlinear and time-varying elements. Previous work has demonstrated that a class of linear time-varying (LTV) antennas employing parametric amplification by varying the antenna’s reactance over time results in the capability for significant bandwidth and gain improvements past traditional limitations. However, due to the disruption of linearity or time-invariance in novel antenna designs, typical communications metrics in the context of these systems are not well-founded, and the integration of mathematical communications theory with the added physical capabilities of new active antenna designs is not formally addressed in either antenna design or communications theory. This thesis focuses on capturing information-theoretic metrics of ESAs, principally the maximum channel capacity and achievable data rate. The simulated responses of an electrically small LTI antenna are compared with the simulated responses of two different LTV parametric amplification antenna designs, and the maximum theoretical capacity and achievable data rates are analyzed. Data rates using realizable modulation and coding schemes are simulated using conventional quadrature amplitude modulation (QAM) and orthogonal frequency division multiplexing (OFDM). The analysis demonstrates that an LTV antenna operating in an internally-noise-limited bandlimited channel can achieve a theoretical performance increase of 2-4x the LTI capacity. In a case where the communication signal is limited to the antenna’s 3 dB bandwidth, the capacity gains can improve as much as 12x the LTI capacity due to the significant bandwidth broadening capabilities, and the data rate improvement is achievable using standard communications methods. Considering the significantly increased data rates, these novel antenna designs show promise in dramatically improving the efficiency, reliability, and connectivity of modern communications
Supervisor Responses to Subordinate Social Issue Advocacy: The Motivating Role of Anticipated Gratitude and Guilt
No full textSocial issues are a frequent topic of discussion in organizations today. Given that many employees view their organizations as a place to initiate change on such issues, recent work has examined how employees sell social issues to top management in an effort to garner organizational support for addressing these matters. However, we lack an understanding of what occurs when these discussions take place between employees themselves, particularly between supervisors and their subordinates. The purpose of this dissertation, then, is to provide a theoretical and empirical examination of how supervisors respond when they are the target of subordinates’ social issue advocacy. By integrating the followership perspective of leadership with a regulatory focus lens to examine this area, my dissertation makes key contributions to this nascent literature on social issues in the workplace.
First, my dissertation addresses when social issue discussions occur at work by looking at social issue advocacy, or when subordinates pressure their supervisors to address social issues at work. Whereas most research has viewed supervisors as the proponents for change regarding social issues, it remains unclear what occurs when they are the targets of social issue advocacy. Second, this research contributes to our understanding of supervisors’ motivation for addressing social issues by understanding to whom they respond. It may be that supervisors address social issues at the urging of subordinates and account for subordinate characteristics (i.e., status and consensus) in evaluating how to respond. Finally, my dissertation extends our knowledge of why supervisors may address social issues at work. I propose two subordinate-focused motivating factors—anticipated gratitude and anticipated guilt—that guide the supervisor’s response to subordinate advocacy and ultimately may lead to supervisor championing social issues at work.
I performed two experimental vignette studies and one survey study to examine my model. In the experiments, the results showed that subordinate social issue advocacy is positively related to both anticipated gratitude and anticipated guilt. Moreover, subordinate status significantly moderated the effect of subordinate advocacy on anticipated guilt—whereby a supervisor experiences higher anticipated guilt when a higher-status subordinate engages in social issue advocacy. However, status did not significantly moderate the effect of subordinate advocacy on gratitude, and I did not find support for a conditional effect of consensus on either path. In the survey study of 100 supervisor-subordinate pairs, the results largely did not support my model. However, in an exploratory post-hoc analysis, I found support for the effect of supervisor perceptions of subordinate advocacy on anticipated gratitude and anticipated guilt. Moreover, these results showed that anticipated guilt significantly mediates the indirect effect of supervisor perceptions of subordinate advocacy on supervisor championing social issues at work.
Because most of the results did not support most of the hypotheses, I identify and describe methodological limitations that may have contributed to these outcomes. More specifically, I discuss the deficiencies of measuring consensus in the experimental vignette designs, as well as shortcomings with the sample, measures, and timing in the survey study. I then close by outlining future research directions, as well as practical implications for managers and organizations
Dust Formation and Destruction in Core Collapse Supernovae Explosions
Get PDFDust is a crucial component of the Interstellar Medium (ISM) and an important driver in many astrophysical processes. Dust formed from evolved stars increases the metallicity of the ISM, enriching it with heavier elements. Dust makes up the source material of collapsing clouds in the ISM leading to stellar and galactic formation. The stabilization of these systems are aided by dust through absorption and scattering of excess energy. As stellar systems evolve and undergo supernova and mass loss events, enriched dust is produced, further enhancing the metallicity of the ISM. However, despite the importance of dust, the processes that produce dust are not well understood.
Core-Collapse Supernovae are one source of dust. Dying massive stars explode, sending their constituent material into the Interstellar Medium, which as the ejecta expands and cools, material condenses and nucleates forming dust grains. I investigate the formation, survivability, and properties of dust. In Chapter 2, dust grain nucleation in CCSNe is discussed. A revised formulation of Kinetic Nucleation Theory (KNT) is used to track the nucleation and growth of dust grains in the ejecta. The affects of the progenitor system on the amount and type of dust is explored, showing a strong dependence on explosion energy. I discuss the code and methods used to model dust nucle- ation and destruction in Chapter 3. The sputtering and erosion of dust grains in CCSNe shocks are explored in Chapter 4. The erosion and survival of this nucleated dust is modeled through thermal and non-thermal sputtering by the surrounding gas and shocks. The optical properties and scattering of light by surviving dust grains is modeled by Mie scattering in Chapter 5. A discussion of observations of dust in variable star systems and supernovae is outlined in Chapter 6