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Achilles, Daryl. "Generation and characterisation of multiphoton nonclassical states of light". Thesis, University of Oxford, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.442123.
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Baune, Christoph [Verfasser]. "Frequency up-conversion of nonclassical states of light / Christoph Baune". Hannover : Technische Informationsbibliothek (TIB), 2016. http://d-nb.info/111695611X/34.
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Thomsen, Laura Kathrine Wehde, i n/a. "Using Quantum Feedback to Control Nonclassical Correlations in Light and Atoms". Griffith University. School of Science, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20040406.124012.
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This thesis considers two types of applications of quantum feedback control; feedback creation of
nonclassical states of light, and controlling nonclassical properties of an ensemble of atoms. An electro-optical feedback loop will create an in-loop field with nonclassical photon statistics similar to squeezed light, resulting in fluorescence line-narrowing of a two-level atom coupled to such light. We extend this theory to study a three-level atom coupled to broadband squashed light, and confirm the two-level atom line-narrowing using a more realistic non-Markovian description of the feedback loop. The second type of application utilizes continuous QND measurement of atomic ensembles. If we measure the collective spin, then the system experiences conditional spin squeezing dependent on the measurement results. We show that feedback based on these results can continuously drive the system into the same conditioned state, resulting in deterministically reproducible spin squeezing. If we measure the atom number fluctuations of a BEC, then, due to the nonlinearity of atomic self interactions, this is also information about phase fluctuations. We show that feedback based on this information can greatly reduce the collisional broadening of the linewidth of an atom laser out-coupled from the condensate.
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Thomsen, Laura Kathrine Wehde. "Using Quantum Feedback to Control Nonclassical Correlations in Light and Atoms". Thesis, Griffith University, 2004. http://hdl.handle.net/10072/367297.
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This thesis considers two types of applications of quantum feedback control; feedback creation of nonclassical states of light, and controlling nonclassical properties of an ensemble of atoms. An electro-optical feedback loop will create an in-loop field with nonclassical photon statistics similar to squeezed light, resulting in fluorescence line-narrowing of a two-level atom coupled to such light. We extend this theory to study a three-level atom coupled to broadband squashed light, and confirm the two-level atom line-narrowing using a more realistic non-Markovian description of the feedback loop. The second type of application utilizes continuous QND measurement of atomic ensembles. If we measure the collective spin, then the system experiences conditional spin squeezing dependent on the measurement results. We show that feedback based on these results can continuously drive the system into the same conditioned state, resulting in deterministically reproducible spin squeezing. If we measure the atom number fluctuations of a BEC, then, due to the nonlinearity of atomic self interactions, this is also information about phase fluctuations. We show that feedback based on this information can greatly reduce the collisional broadening of the linewidth of an atom laser out-coupled from the condensate.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Science
Full Text
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Fedortchenko, Sergueï. "The ultrastrong coupling regime as a resource for the generation of nonclassical states of light". Thesis, Sorbonne Paris Cité, 2017. http://www.theses.fr/2017USPCC279/document.
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Depuis l’avènement de la mécanique quantique, l’étude des interactions lumière-matière à l’échelle quantique s’est énormément développée en tant que domaine de recherche. Par exemple, grâce à des prédictions théoriques surprenantes, des interactions d’une force sans précédant ont été démontrées entre de la matière et des radiations terahertz et microonde. Ces résultats correspondent à un régime dit de couplage ultrafort, atteint lorsque l’énergie d’interaction devient comparable aux énergies propres de la lumière et de la matière lorsque celles-ci n’interagissent pas. Dans ce régime, des propriétés intrigantes peuvent subsister telles que la présence de photons même lors qu’aucune énergie n’est fournie au système. Cependant, ces photons ne peuvent, a priori, être émis du système vers l’extérieur de manière à pouvoir être mesurés et par conséquent démontrer ces propriétés.Dans cette thèse, nous avons étudié ces propriétés intrigantes et proposé plusieurs moyens permettant d’y accéder expérimentalement. Nous nous sommes appuyés sur plusieurs plate-formes physiques qui sont de bon candidats pour ces études, et pour chacun de ces systèmes nous avons mis au point un modèle mettant en évidence ces propriétés d’une manière ou d’une autre. De cette façon, nous avons exploré le lien entre le régime de couplage ultrafort et la génération d’états non-classiques de la lumière. En outre, dans une étude plus ouverte nous avons montré que les interactions lumière- matière dans l’une de ces plate-formes peuvent être utilisés pour concevoir des protocols de communication quantique. En plus de montrer un intérêt fondamental, nos résultats s’inscrivent dans une optique de développement d’applications pour les technologies quantiques en utilisant différents systèmes expérimentaux disponibles actuellementSince the advent of quantum mechanics, the study of light-matter interactions at thequantum level has been greatly developed as a research field. For instance, surprisingtheoretical predictions gave rise to experiments with unprecedented interactionstrengths between matter, and terahertz and microwave radiations. These results correspondto the so-called ultrastrong coupling regime, that is reached when the interactionenergy becomes comparable to the typical energies of the light and matter when they arenot interacting. In this regime, intriguing properties can be found such as the presenceof photons even when no energy is given to the system. However, these photons cannot,a priori, be emitted from the system to the outside world in order to be measured andtherefore demonstrate these properties. In this thesis, we studied these intriguing properties and proposed several means toaccess them experimentally. We relied on several physical platforms which are goodcandidates for such studies, and for each one of these systems we devised a model thatcan evidence these properties one way or another. By doing so, we explored the linkbetween the ultrastrong coupling regime and the generation of nonclassical states oflight. Additionally, as an outlook we showed that the light-matter interactions in oneof these platforms could be used to design quantum communication protocols. On topof showing fundamental interest, our results fit in the line of developing applications forquantum technologies using different experimentally available systems
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Lolli, Jared. "Quantum Measurement and Feedback Control of highly nonclassical Photonic States". Thesis, Sorbonne Paris Cité, 2017. http://www.theses.fr/2017USPCC223/document.
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Ces dernières années, les progrès réalisés dans le contrôle de l'interaction lumière-matière au niveau quantique ont conduit à de nombreuses avancées en optique quantique, en particulier dans l'étude de phénomènes quantiques fondamentaux, dans la conception de systèmes quantiques artificiels et dans les applications en information quantique. Il a notamment été possible d'augmenter considérablement l'intensité de l'interaction lumière-matière et de contrôler le couplage de systèmes quantiques à leur environnement, afin d'obtenir des états non conventionnels et fortement non classiques. Cependant, pour exploiter ces états quantiques en vue d'applications technologiques, il est crucial de pouvoir mesurer et contrôler ces systèmes avec précision. Dans ce contexte, ce travail de thèse est consacré à l'étude de nouveaux protocoles pour la mesure et le contrôle de systèmes quantiques dans lesquels des fortes interactions et des symétries particuliers conduisent à la génération d'états fortement non classiques. Nous nous intéressons dans un premier temps au régime de couplage ultra-fort de l'électrodynamique quantique en cavité (et de circuit). Plus précisément, l'état de fondamental n'est plus le vide standard, car il devient énergiquement favorable qu'il contienne des photons.Dans ce régime on peut même obtenir des chat de Schrödinger comme état fondamental.En revanche, pour assurer la conservation de l'énergie, les photons contenus dans ce vide exotique sont liés à la cavité et ne peuvent pas s'échapper dans l'environnement. Cela signifie qu'ils ne peuvent être mesurés par simple photodétection. Nous proposons dans ce travail un protocole spécialement conçu pour surmonter cette difficulté. Nous montrons qu'il est possible de déduire les propriétés photoniques de l'état fondamental à partir du déplacement de Lamb d'un système à deux niveaux auxiliaire.Les résonateurs optiques à paires de photons constituent une autre classe de systèmes dans lesquels la symétrie de parité conduit à des états quantiques non conventionnels. Grâce à "l'ingénierie de réservoir", il est aujourd'hui possible de contrôler l'interaction d'un système avec son environnement, de façon à le stabiliser dans des états quantiques particulièrement intéressants. En particulier, quand un résonateur (une cavité optique) est couplé à l'environnement par échange de paires de photons, il est possible de créer de chats de Schrödinger optiques dans la dynamique transitoire du système. Les corrélations quantiques de ces états sont par contre rapidement perdues en raison de la présence inévitable de dissipation à un photon. Protéger le système contre cette perturbation est le but du protocole de feedback basé sur la parité que nous présentons dans cette thèseIn recent years, the field of quantum optics has thrived thanks to the possibility of controlling light-matter interaction at the quantum level.This is relevant for the study of fundamental quantum phenomena, the generation of artificial quantum systems, and for quantum information applications.In particular, it has been possible to considerably increase the intensity of light-matter interaction and to shape the coupling of quantum systems to the environment, so to realise unconventional and highly nonclassical states.However, in order to exploit these quantum states for technological applications, the question of how to measure and control these systems is crucial.Our work is focused on proposing and exploring new protocols for the measurement and the control of quantum systems, in which strong interactions and peculiar symmetries lead to the generation of highly nonclassical states.The first situation that we consider is the ultrastrong coupling regime in cavity (circuit) quantum electrodynamics.In this regime, it becomes energetically favourable to have photons and atomic excitations in the ground state, that is no more represented by the standard vacuum.In particular, in case of parity symmetry, the ground state is given by a light-matter Schrödinger cat state.However, according to energy conservation, the photons contained in these exotic vacua are bound to the cavity, and cannot be emitted into the environment.This means that we can not explore and control them by simple photodetection.In our work we propose a protocol that is especially designed to overcome this issue.We show that we can infer the photonic properties of the ground state from the Lamb shift of an ancillary two-level system.Another class of systems in which the fundamental parity symmetry leads to very unconventional quantum states is given by two-photon driven-dissipative resonators.Thanks to the reservoir engineering, it is today possible to shape the interaction with the environment to stabilize the system in particularly interesting quantum states.When a resonator (an optical cavity) exchanges with the environment by pairs of photons, it has been possible to observe the presence of optical Schrödinger cat states in the transient dynamics of the system.However, the quantum correlations of these states quickly decays due to the unavoidable presence of one-photon dissipation.Protecting the system against this perturbation is the goal of the parity triggered feedback protocol that we present in this thesis
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Milanović, Josip [Verfasser], i Gerd [Akademischer Betreuer] Leuchs. "Generation of Nonclassical Polarization States of Intense Light using PhotonicCrystal Fibers / Josip Milanovic. Betreuer: Gerd Leuchs". Erlangen : Universitätsbibliothek der Universität Erlangen-Nürnberg, 2013. http://d-nb.info/1031317848/34.
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Souza, Douglas Delgado de 1987. "Informação quântica com estados coerentes comprimidos da luz". [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/276940.
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Orientador: Antonio Vidiella BarrancoTese (doutorado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin
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Resumo: Na primeira parte deste trabalho seguimos os estudos de Hirota e colaboradores e definimos quatro estados quase-Bell baseados em estados coerentes comprimidos da luz. Dois desses estados são maximamente emaranhados, enquanto o emaranhamento dos outros dois depende apenas da sobreposição entre os estados coerentes comprimidos que os compõem. A partir destes estados quase-Bell, definimos novos estados interpolados cujo emaranhamento é também governado por um parâmetro de interpolação adicional e estudamos algumas das propriedades destes estados (emaranhamento e eficiência energética). Por fim, usamos estes estados e definimos alguns estados de Werner, com os quais analisamos de forma simples uma possível influência de um ambiente dissipativo parametrizado pela probabilidade de o estado de Werner estar em sua forma emaranhada ou misturada. Para esta análise usamos os conceitos de separabilidade e emaranhamento. Na segunda parte estudamos a estimativa de fase quântica usando estados gaussianos puros (estados coerentes comprimidos). Iniciamos com a estimativa da fase introduzida por um operador unitário em cujo hamiltoniano está presente uma perturbação linear nos operadores de criação e aniquilação, além do operador de número de fótons responsável pela evolução de fase (perturbação linear unitária). Obtemos quais são os estados gaussianos ótimos para a estimativa desta fase e analisamos a optimalidade da detecção homódina. A seguir, consideramos o parâmetro de perturbação como uma variável aleatória que obedece a uma distribuição gaussiana de probabilidades (perturbação linear aleatória) e novamente obtemos os estados de sonda ótimos e analisamos a optimalidade da detecção homódina. Por fim, estudamos a estimativa de fase com perturbação linear unitária utilizando os estados quase-Bell interpolados definidos na primeira parte deste trabalho e verificamos que a utilização de emaranhamento permite uma melhor estimativa de fase para uma mesma energia disponível
Abstract: In the first part of this work we follow the studies of Hirota and collaborators and we define four quasi-Bell states based on squeezed coherent states of light. Two of these states are maximally entangled, while the entanglement of the other two depends only on the overlap between the squeezed coherent states that were combined. From these quasi-Bell states we define new interpolated states for which the entanglement is also governed by an additional interpolation parameter, and we study some of the properties of these states (entanglement and energy efficiency). Finally, we use these states to define some Werner states, which we use to study in a simple way the possible influence of some dissipative environment parameterized by the probability that the Werner state is entangled or mixed. For this analysis we use the concepts of separability and entanglement. In the second part, we study the quantum phase estimation using pure Gaussian states (squeezed coherent states). We begin with the estimation of the phase introduced by a unitary operator whose Hamiltonian also contains a disturbance that is linear in the creation and annihilation operators in addition to the photon number operator responsible for the phase evolution (unitary linear disturbance). We find what are the optimal Gaussian states for this phase estimation and we also analyze the optimality of the homodyne detection. Next, we consider the disturbance parameter to be a random variable submitted to a Gaussian distribution (random linear disturbance) and again we find what are the optimal probe states and analyze the optimality of the homodyne detection. Finally we study the phase estimation with unitary linear disturbance using the interpolated quasi-Bell states defined in the first part of this work and we verify that the use of entanglement leads to a better phase estimation for the same amount of available energy
Doutorado
Física
Doutor em Ciências
2011/00220-5
FAPESP
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Soares, Antonio Augusto. "Manipulação de estados quânticos da luz via espelhos semi-transparentes". [s.n.], 2002. http://repositorio.unicamp.br/jspui/handle/REPOSIP/277389.
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Orientador: Antonio Vidiella BarrancoDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin
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Resumo: Não informado
Abstract: Not informed
Mestrado
Física
Mestre em Física
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Denker, Timo [Verfasser]. "High-precision metrology with high-frequency nonclassical light sources / Timo Denker". Hannover : Technische Informationsbibliothek (TIB), 2016. http://d-nb.info/1112948473/34.
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Burks, Sidney. "Towards a Quantum Memory for Nonclassical Light with Cold Atomic Ensembles". Paris 6, 2010. http://www.theses.fr/2010PA066380.
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Une mémoire quantique reversible permettant de stocker et relire de l'information quantique est une composante majeure dans la mise en oeuvre de nombreux protocoles d'information quantique. Comme la lumière est un porteur de l'information quantique fiable sur des longues distances, et comme les atomes offrent la possibilité d'obtenir de longues durées de stockage, le recherche actuelle sur la création d'une mémoire quantique se concentre sur la transfert des fluctuations quantiques de la lumière sur des cohérences atomiques. Le travail réalisé durant cette thèse porte sur le développement d'une mémoire quantique pour la lumière comprimée, utilisant un ensemble d'atomes froids de Cesium stockés dans un piège magnéto-optique. Nos deux principaux objectifs étaient le developpement d'une source de lumière non-classique, et le developpement d'un millieu atomique pour le stockage de celle-ci. Tout d'abord, nous commençons par présenter la construction d'un oscillateur paramétrique optique qui utilise un cristal nonlineaire de PPKTP. Cet OPO fonctionne comme source d'états de vide comprimé resonant avec la raie du Cesium. Nous caractérisons ces états grâce à une reconstruction par tomographie quantique, en utilisant une approche de vraisemblance maximale. Ensuite, nous examinons une nouvelle expérience qui nous permet d'utiliser comme millieu de stockage des atomes froids de Césium dans un piège magneto-optique récemment dévéloppé. Car cette expérience exige l'utilisation de nouveaux outils et techniques, nous discutons le developpement de ceux-ci, et comment ils ont contribué à notre progression vers le stockage des états quantiques dans nos atomes des Cesium, et finalement vers l'intrication de deux ensembles atomiques.
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Elliott, Matthew. "Theory of nonclassical photonic states in driven-dissipative circuit quantum electrodynamics". Thesis, University of Surrey, 2017. http://epubs.surrey.ac.uk/841210/.
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Superconducting circuits provide an architecture upon which cavity quantum electrodynamics (QED) can be implemented at microwave frequencies in a highly tunable environment. Known as circuit QED, these systems can achieve larger nonlinearities, stronger coupling and greater controllability than can be achieved in cavity QED, all in a customisable, solid state device, making this technology an exciting test bed for both quantum optics and quantum information processing. These new parameter regimes open up new avenues for quantum technology, while also allowing older quantum optics results to finally be tested. In particular is is now possible to experimentally produce nonclassical states, such as squeezed and Schr\"odinger cat states, relatively simply in these devices. Using open quantum systems methods, in this thesis we investigate four problems which involve the use of nonclassical states in circuit QED. First we investigate the effects of a Kerr nonlinearity on the ability to preserve transported squeezed states in a superconducting cavity, and whether this setup permits us to generate, and perform tomography, of a highly squeezed field using a qubit, with possible applications in the characterisation of sources of squeezed microwaves. Second, we present a novel scheme for the amplification of cat states using a coupled qubit and external microwave drives, inspired by the stimulated Raman adiabatic passage. This scheme differs from similar techniques in circuit QED in that it is deterministic and therefore compatible with a protocol for stabilising cat states without the need for complex dissipation engineering. Next we use solutions of Fokker-Planck equations to study the exact steady-state response of two nonlinear systems: a transmon qubit coupled to a readout resonator, where we find good agreement with experiments and see simultaneous bistability of the cavity and transmon; and a parametrically driven nonlinear resonator, where we compare the classical and quantum phases of the system and discuss applications in the generation of squeezed states and stabilisation of cat states. Finally, we investigate the use of two different types of superconducting qubits in a single experiment, seeing that this enables engineering of the self- and cross-Kerr effects in a line of cavities. This could provide a valuable means of entangling cavity states, in addition to a resource for quantum simulation.
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Kettler, Jan [Verfasser]. "Telecom-wavelength nonclassical light from single In(Ga)As quantum dots / Jan Kettler". München : Verlag Dr. Hut, 2017. http://d-nb.info/1128466880/34.
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Kettler, Jan Ferdinand [Verfasser]. "Telecom-wavelength nonclassical light from single In(Ga)As quantum dots / Jan Kettler". München : Verlag Dr. Hut, 2017. http://d-nb.info/1128466880/34.
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Mumba, Mambwe. "EFFECTS OF COUPLING BETWEEN CENTER OF MASS MOTION OF AN ATOM AND A CAVITY MODE: PHOTON STATISTICS AND WAVE-PARTICLE CORRELATIONS". Connect to this document online, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=miami1121433361.
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Thesis (M.S.)--Miami University, Dept. of Physics, 2005.Title from first page of PDF document. Document formatted into pages; contains [1], v, 296 p. : ill. Includes bibliographical references (p. 393-396).
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Mehmet, Moritz [Verfasser]. "Squeezed light at 1064 nm and 1550 nm with a nonclassical noise suppression beyond 10 dB / Moritz Mehmet". Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover (TIB), 2012. http://d-nb.info/1022760688/34.
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Bayraktaroglu, Baran. "Light-states in Conformal Field Theories". Thesis, Uppsala universitet, Teoretisk fysik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-442580.
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Lyubomirsky, Ilya. "Quantum reality and squeezed states of light". Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/36431.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1994.Includes bibliographical references (leaves 67-71).
by Ilya Lyubomirsky.
M.S.
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Brisudova, Martina Maria. "QCD bound states in light-front Hamiltonian approach /". The Ohio State University, 1997. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487942739806751.
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Laycock, Thomas Henry. "Creation and manipulation of quantum states of light and cold atoms using Rydberg states". Thesis, University of Nottingham, 2013. http://eprints.nottingham.ac.uk/13800/.
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Rydberg atoms are often proposed as the basis of quantum computing and quantum information protocols. One of the central reasons for this is that they provide a strong and long-ranged interaction that can be coherently switched on and off. This thesis details two techniques which use the exaggerated properties of Rydberg atoms to manipulate both the quantum state of the atom itself and that of the external light field. The first proposal initially focuses on the creation of many-body quantum states from two-level atoms trapped in a two-dimensional lattice. This approach uses the van der Waals interaction present between alkali metal atoms in highly excited Rydberg s-states. The approximate solution of the corresponding Hamiltonian is detailed in the regime where the laser driving is the largest energy scale of the system. The states which are most likely achieved using an oscillating laser detuning are then determined. These states are then taken as the basis for the creation of deterministic single-photons, whose properties are shown to rely on the interplay between interatomic spacing and the geometry of the lattice. The second technique described uses the coupling between a Rydberg atom and a moving electron to manipulate the atomic state. In this system, the atom is initially excited to a Rydberg s-state and trapped at a finite distance from an electron waveguide. Two analytical methods are used to show that the final state of the atom depends strongly on the direction and modulus of the electron momentum. A complementary numerical simulation shows that the atoms may be left in a polarised state, suggesting the possibility of using this setup to ‘switch on’ permanent electric dipoles in the atoms. This investigation leads naturally to a system where multiple interacting atoms are trapped close to the waveguide, allowing various many-body states to be accessed.
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Ashwood, Nicholas Ian. "The search for molecular cluster states in light nuclei". Thesis, University of Birmingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288654.
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Rick, James Jonathan. "Masters of Light and Flight/ ”This Most Republican Amalgamation”". W&M ScholarWorks, 2017. https://scholarworks.wm.edu/etd/1516639665.
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Masters of Light and Flight: The Spectacle of Invention in fin-de-siècle U.S. Popular Culture, 1876-1917 Popular fascination with inventors in U.S. popular culture was at a high point in the decades surrounding the turn of the twentieth century. This paper analyzes the discourse surrounding inventors in the aviation and aeronautics industries: including Thomas Alva Edison, Nicola Tesla, Glenn Curtiss and Wilbur and Orville Wright. By analyzing invention as a spectacle, it sheds light on the relationships between the spectacle of invention and industrial modernity. On the one hand, inventors became popular symbols of control over the process of labor and its products during an era when the alienation of industrial and commercial labor, as well as the rising dangers of urban life were on the minds of many Americans. at the same time, popular coverage of inventors reminded the average person that mastery was no longer available to the ordinary but now only to exceptional celebrity-inventors. Finally, the discourse surrounding these celebrity-inventors facilitated a cultural transition from a 19th century worldview in which value was placed upon individual mastery to a 20th century worldview in which value was placed upon the collective mastery of corporations and the state. “This Most Republican Amalgamation:” The Ideology of the Manual Labor Movement in Early U.S. Education. In the 1820s and 1830s, reformers from disparate ideological traditions—including utopian socialists, abolitionist reformers, and more conservative reformers—were drawn to the manual labor system of education. They sought to introduce mechanical and agricultural labor into the curricula of colleges and seminaries for young men. Reformers believed that this would make education more affordable and healthful. This paper analyzes the way different supporters of the manual labor movement articulated visions of republicanism and Northern nationalism in their efforts to promote the manual labor system. In their articulations of republicanism and Northern nationalism, abolitionist and socialist manual laborites created legitimate space for the exercise of state power to promote and protect equality.
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Zhang, Jie. "Study of super-deformed #alpha#-cluster states in light nuclei". Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.294227.
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Zheng, Zhan. "Two-photon--two-atom excitation with quantum multimode light states". Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066589/document.
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Deux photons - deux atomes (2P2A) excitation s’avère être un banc de test importantde propriétés optiques quantiques. Depuis 1980, on sait que la probabilité de transition2P2A peut être grandement améliorée en utilisant la source monochromatique cohérenteavec la présence d’interactions atomiques qui induisent un pic de résonance de 2P2A. En2004 , Muthukrishnan et al. sont trouvés une grande amélioration de la transition ainsique d’une résonance de 2P2A, quand une source de deux photons intriqués, provenant dela radiation d’un atome cascade à trois niveaux, interagit avec les deux atomes différentsde l’ interaction. Leur conclusion est que : dans certaines situations, l’intrication peutremplacer un vrai hamiltonien d’interaction, qui est une déclaration de grande portée etune propriété importante liée à l’intrication. Ce phénomène mérite plus d’attention et defavoriser la compréhensionTwo-photonÐtwo-atom (2P2A) excitation turns out to be an important test bench of quantum optical properties. In 2004, Muthukrishnan et al. announced a great enhancement of the transition at 2P2A resonance, when an entangled two-photon state, coming from a three-level cascade, interacts with two non-interacting atoms. Their conclusion: in some situations, entanglement can replace a real interaction Hamiltonian, reveals an important property related to entanglement. In this thesis, We study in detail the efficiency of various multimode two-photon states of light to induce the simultaneous excitation of two atoms of different kinds under 2P2A resonance condition. We find that several separable, correlated states, produced either by an atomic cascade or parametric down-conversion, or even appropriate combinations of coherent states, have comparable efficiencies as the photon state produced by an atomic cascade. We conclude that the true physical origin of the enhancement is the frequency anti-correlations, neither the temporal correlations, time ordering, nor entanglement. To present, we are not sure whether or not the enhancement is a quantum effect. We also studied: 1. the optimized 2P2A transition probability for a given photon spectrum; 2. the influence coming from finite lifetimes of the excited detecting atoms; 3. the 2P2A transition probability in the presence of atomic interaction
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Cooper, Merlin Frederick Wilmot. "Measurement and manipulation of quantum states of travelling light fields". Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:79164748-ebb3-48e2-b4d4-1a4766d29217.
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This thesis is concerned with the generation of non-classical quantum states of light, the photon-level manipulation of quantum states and the accurate tomography of both quantum states and quantum processes. In optics, quantum information can be encoded and processed in both discrete and continuous variables. Hybrid approaches combining for example homodyne detection with conditional state preparation and manipulation are gaining increasing prominence. The development and characterization of a time-domain balanced homodyne detector (BHD) is presented. The detector has a bandwidth of 80 MHz, a signal-to-noise ratio of 14.5 dB and an efficiency of 86% making it well-suited to pulse-to-pulse measurement of quantum optical states. The BHD is employed to perform quantum state tomography (QST) of non-classical multi-photon Fock states generated by spontaneous parametric down-conversion. A detailed investigation of the mode-matching between the local oscillator used for homodyne detection and the generated Fock states is presented. The one-, two- and three-photon Fock states are reconstructed with a combined preparation and detection efficiency exceeding 50%. Fock states have a number of applications in quantum state engineering, where non-classical ancilla states and conditional measurements enable photon-level manipulation of quantum states. Fock state filtration (FSF) is investigated - an example of a post-selected beam splitter which is a basic building block for many quantum state engineering protocols. A model is developed incorporating the effect of experimental imperfections. An experimental implementation of a Fock state filter is fully characterized by means of coherent-state quantum process tomography (QPT). The reconstructed process is found to be consistent with the model. The filter preferentially removes the single-photon component from an arbitrary input quantum state. Calibration of optical detectors in the quantum regime is discussed. Quantum detector tomography (QDT) is reviewed and contrasted with a new technique for performing QST with a calibrated detector known as the fitting of data patterns (FDP). The first experimental characterization of a BHD is performed by probing the detector with phase-averaged coherent states. The FDP method is shown to be applicable to the estimation of quantum processes, where a detector response is not assumed - thus demonstrating the versatility of the FDP approach as a new method in the quantum tomography toolbox.
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Dhoot, Anoop Singh. "Optical probing of excited states in conjugated polymer devices". Thesis, University of Cambridge, 2001. https://www.repository.cam.ac.uk/handle/1810/272179.
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Dickinson, David B. ""Old blue light" the religious beliefs and military leadership of Stonewall Jackson /". Theological Research Exchange Network (TREN), 1997. http://www.tren.com.
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Wolfgramm, Florian. "Atomic quantum metrology with narrowband entangled and squeezed states of light". Doctoral thesis, Universitat Politècnica de Catalunya, 2012. http://hdl.handle.net/10803/98460.
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The use of light, especially of laser light, is in many cases the most sensitive way to perform measurements. However, the highest sensitivity that can be achieved with laser light as probe is bounded by the standard quantum limit (SQL). As many instruments are approaching this fundamental limit, it becomes crucial to explore ways to overcome the SQL. Quantum metrology offers the possibilities to increase the sensitivities of the most accurate measurements beyond the SQL by using photonic quantum states of light as a tool. Two well-known classes of quantum states that provide a metrological advantage and break the SQL are squeezed states and a certain class of entangled states, called NOON states. While it is of special interest to apply these quantum states to atomic systems, such as atomic vapors, this requires quantum states of the highest quality in terms of purity, fidelity, brightness, and indistinguishability. Most importantly, for the probing of atomic systems, the quantum states need to be extremely narrowband to match the atomic linewidths. As NOON states are usually generated in a broadband spontaneous parametric down-conversion (SPDC) process, they are not compatible with narrowband atomic resonances.
The goal of this thesis was the generation of suitable narrowband entangled and squeezed quantum states of light and their application to atomic systems. To increase the rate of atom-resonant SPDC photons by orders of magnitude, we used a cavity-enhanced setup. Polarization-squeezed states and polarization-entangled NOON states were created. The spectral brightness of the generated NOON states is one of the highest of pairs of indistinguishable photons reported so far. The photon pairs were carefully characterized by full quantum state tomography showing high fidelities with a perfect NOON state. After filtering the photon source output by a novel filter based on the “interaction-free measurement” scheme, a cross-correlation measurement demonstrated its potential as a narrowband heralded single-photon source, needed for example in quantum information. To apply these states in a quantum metrology scheme and to show the metrological advantage, we chose an atomic magnetometer as a model system. The assembled shot-noise-limited magnetometer is based on the Faraday effect in a vapor of hot rubidium atoms. It could be demonstrated that both quantum states perform better in the magnetometer application than any classical state, i.e., they break the SQL. In the case of NOON states, this is the first use of multi-photon coherence in an atomic experiment. In addition to applications in quantum metrology, the presented techniques of quantum-light generation and filtering are also directly applicable to quantum information tasks, especially to the use in quantum memories.El uso de la luz, en particular la luz láser es, en muchos casos, el método que permite realizar mediciones de la manera más sensible. No obstante, la mayor sensibilidad que se puede conseguir gracias a la luz láser como sistema de sondeo queda delimitada por el límite cuántico estándar (SQL). Visto que muchos instrumentos se están acercando a este límite fundamental, es crucial explorar formas de superar el SQL. La metrología cuántica ofrece la posibilidad de incrementar la sensibilidad de las medidas más precisas más allá del SQL empleando los estados cuánticos de luz como herramienta. Dos categorías conocidas de estados cuánticos que brindan una ventaja metrológica y rompen con el SQL son los estados “comprimidos” y ciertas categorías de estados entrelazados llamados estados “NOON”. Aunque es de especial interés aplicar estos estados cuánticos a los sistemas atómicos, como a los vapores atómicos, se requieren estados cuánticos de óptima calidad en términos de pureza, fidelidad, luminosidad e identidad. Lo más importante para los sistemas atómicos de investigación es que los estados cuánticos sean de banda extremadamente estrecha para que coincidan con el ancho de banda de átomos. Puesto que los estados NOON suelen ser generados en un proceso de conversión espontánea paramétrica descendente (SPDC) de banda ancha, no son compatibles con las resonancias atómicas de banda estrecha. El objeto de esta tesis fue la generación de estados cuánticos de luz apropiados de banda estrecha, entrelazados y comprimidos, y su aplicación en los sistemas atómicos. Para incrementar el número de fotones generados por SPDC resonantes con la transición atómica por órdenes de magnitud, se empleó un sistema aumentado por un resonador. Se crearon estados de polarización comprimida y estados NOON de polarización entrelazada. La luminosidad espectral de los estados NOON generada supone una de las más altas que se hayan reportado hasta el momento entre pares de fotones idénticos. Los pares de fotones fueron cuidadosamente caracterizados por medio de una tomografía completa del estado cuántico que muestra la gran fidelidad con un estado NOON perfecto. Después de filtrar la producción de la fuente de fotones por medio de un novedoso filtro basado en el esquema “interaction-free measurement”, una medida de correlación cruzada demostró su potencial como fuente de fotones individuales anunciados de banda estrecha que resulta necesaria, por ejemplo, en la información cuántica. Para aplicar estos estados en un esquema de metrología cuántica y demostrar la ventaja metrológica, elegimos un magnetómetro atómico como sistema modelo. El montaje del magnetómetro delimitado por el límite cuántico estándar se basa en el efecto Faraday en un vapor de átomos de rubidio calientes. Se podía demostrar que el comportamiento de ambos estados cuánticos es superior en la aplicación con el magnetómetro que cualquier estado clásico, es decir, que superan el SQL. En el caso de los estados NOON, este es el primer uso de la coherencia multifotónica en un experimento atómico. Además de las aplicaciones en la metrología cuántica, las técnicas presentadas de generación de luz cuántica y filtración también son directamente aplicables a las tareas de información cuántica, en especial al uso en las memorias cuánticas.
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Rey, Diana. "A Gasoline Demand Model for the United States Light Vehicle Fleet". Master's thesis, University of Central Florida, 2009. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2351.
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The United States is the world's largest oil consumer demanding about twenty five percent of the total world oil production. Whenever there are difficulties to supply the increasing quantities of oil demanded by the market, the price of oil escalates leading to what is known as oil price spikes or oil price shocks. The last oil price shock which was the longest sustained oil price run up in history, began its course in year 2004, and ended in 2008. This last oil price shock initiated recognizable changes in transportation dynamics: transit operators realized that commuters switched to transit as a way to save gasoline costs, consumers began to search the market for more efficient vehicles leading car manufactures to close 'gas guzzlers' plants, and the government enacted a new law entitled the Energy Independence Act of 2007, which called for the progressive improvement of the fuel efficiency indicator of the light vehicle fleet up to 35 miles per gallon in year 2020. The past trend of gasoline consumption will probably change; so in the context of the problem a gasoline consumption model was developed in this thesis to ascertain how some of the changes will impact future gasoline demand. Gasoline demand was expressed in oil equivalent million barrels per day, in a two steps Ordinary Least Square (OLS) explanatory variable model. In the first step, vehicle miles traveled expressed in trillion vehicle miles was regressed on the independent variables: vehicles expressed in million vehicles, and price of oil expressed in dollars per barrel. In the second step, the fuel consumption in million barrels per day was regressed on vehicle miles traveled, and on the fuel efficiency indicator expressed in miles per gallon. The explanatory model was run in EVIEWS that allows checking for normality, heteroskedasticty, and serial correlation. Serial correlation was addressed by inclusion of autoregressive or moving average error correction terms. Multicollinearity was solved by first differencing. The 36 year sample series set (1970-2006) was divided into a 30 years sub-period for calibration and a 6 year "hold-out" sub-period for validation. The Root Mean Square Error or RMSE criterion was adopted to select the "best model" among other possible choices, although other criteria were also recorded. Three scenarios for the size of the light vehicle fleet in a forecasting period up to 2020 were created. These scenarios were equivalent to growth rates of 2.1, 1.28, and about 1 per cent per year. The last or more optimistic vehicle growth scenario, from the gasoline consumption perspective, appeared consistent with the theory of vehicle saturation. One scenario for the average miles per gallon indicator was created for each one of the size of fleet indicators by distributing the fleet every year assuming a 7 percent replacement rate. Three scenarios for the price of oil were also created: the first one used the average price of oil in the sample since 1970, the second was obtained by extending the price trend by exponential smoothing, and the third one used a longtime forecast supplied by the Energy Information Administration. The three scenarios created for the price of oil covered a range between a low of about 42 dollars per barrel to highs in the low 100's. The 1970-2006 gasoline consumption trend was extended to year 2020 by ARIMA Box-Jenkins time series analysis, leading to a gasoline consumption value of about 10 millions barrels per day in year 2020. This trend line was taken as the reference or baseline of gasoline consumption. The savings that resulted by application of the explanatory variable OLS model were measured against such a baseline of gasoline consumption. Even on the most pessimistic scenario the savings obtained by the progressive improvement of the fuel efficiency indicator seem enough to offset the increase in consumption that otherwise would have occurred by extension of the trend, leaving consumption at the 2006 levels or about 9 million barrels per day. The most optimistic scenario led to savings up to about 2 million barrels per day below the 2006 level or about 3 millions barrels per day below the baseline in 2020. The "expected" or average consumption in 2020 is about 8 million barrels per day, 2 million barrels below the baseline or 1 million below the 2006 consumption level. More savings are possible if technologies such as plug-in hybrids that have been already implemented in other countries take over soon, are efficiently promoted, or are given incentives or subsidies such as tax credits. The savings in gasoline consumption may in the future contribute to stabilize the price of oil as worldwide demand is tamed by oil saving policy changes implemented in the United States.M.S.
Department of Civil and Environmental Engineering
Engineering and Computer Science
Civil Engineering MS
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McDonnell, Joel W. "The electric light and the future: American perceptions and expectations, 1879-1890". Thesis, University of Ottawa (Canada), 1997. http://hdl.handle.net/10393/4314.
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This thesis explores the manner in which electric lighting was applied during the first decade after Edison's Menlo Park demonstration, and how these applications influenced American public perceptions of the technology, particularly in relation to imagined future uses and social meanings. Specifically, the thesis focuses on expectations and perceptions of electric lighting as applied or related to three important aspects of late nineteenth century American society: crime, warfare, and aesthetics and health. Using these three themes, this thesis illustrates how electric lighting was viewed during the 1880's and what hopes and images were attached to it.
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Kokalova, Tzanka T. "Gamma-ray spectroscopy of deformed states in light nuclei and cluster emission". [S.l.] : [s.n.], 2004. http://www.diss.fu-berlin.de/2004/21/index.html.
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Lucivero, Vito Giovanni. "Quantum metrology with high-density atomic vapors and squeezed states of light". Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/403962.
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Nowadays there is a considerable progress in optical magnetometry and spin noise spectroscopy, which use magnetically-sensitive atomic ensembles and optical read-out, approaching the limits set by quantum mechanics. In recent years optical magnetometers have become the most sensitive instruments for measuring low-frequency magnetic fields, achieving sub-femtotesla sensitivity and surpassing the competitive superconducting quantum interference devices (SQUIDs), and have found applications in biomedicine, geophysics, space science as well as in tests of fundamental physics. Another emerging technique is spin noise spectroscopy (SNS), which allows one to determine physical properties of an unperturbed spin system from its power noise spectrum. In the last decade technological advances like real-time spectrum analyzers and shot-noise-limited detectors have allowed improvements in the sensitivity of spin noise detection leading to a broad range of applications in both atomic and solid state physics.
The main goal of this thesis is to address a major outstanding question: whether squeezed light can improve the sensitivity of atomic sensors under optimal sensitivity conditions, typically in a high-density regime due to the statistical advantage of using more atoms.
Firstly, we describe the design, construction and characterization of a new versatile experimental apparatus for the study of squeezed-light atomic spectroscopy within a high-density regime (n=¿10¿^12 ¿cm¿^(-3)) and low-noise (¿pT/vHz) magnetic environment. The new experimental system is combined with an existing source of polarization squeezed light based on spontaneous parametric down conversion (SPDC) in a nonlinear crystal, which is the active medium of an optical parametric oscillator.
Secondly, we report the first experimental demonstration of quantum-enhanced spin noise spectroscopy of natural abundance Rb via polarization squeezing of the probe beam. We found that input squeezing of 3.0 dB improves the signal-to-noise ratio by 1.5 dB to 2.6 dB over the combined (power¿number density) ranges (0.5 mW to 4.0 mW) ¿ (1.5 ׿10¿^12 ¿cm¿^(-3) to 1.3 ׿10¿^13 ¿cm¿^(-3)), covering the ranges used in optimized spin noise spectroscopy experiments. We also show that squeezing improves the trade-off between statistical sensitivity and broadening effects.
Next, we introduce a novel theoretical model by defining a standard quantum limit (SQL) for optically-detected noise spectroscopy, identified as a bound to the covariance of the parameters estimated by fitting power noise spectra. We test the model for spin noise spectroscopy of natural abundance Rb and we demonstrate experimental performance of SNS at the SQL for a coherent probe and below the SQL for a polarization squeezed probe.
Finally, we report an optical magnetometer based on amplitude modulated optical rotation (AMOR), using a 85Rb vapor cell, that achieves room temperature sensitivity of 70 fT/vHz at 7.6 µT and we demonstrate its photon shot-noise-limited (SNL) behaviour from 5 µT to 75 µT. While no quantum resources of light were used in this second experiment, the combination of best sensitivity, in the class of room-temperature scalarHoy en día existe un considerable progreso en la magnetometría óptica y espectroscopía de ruido de espin, que utilizan conjuntos atómicos magnéticamente sensibles y lectura óptica, acercándose a los límites establecidos por la mecánica cuántica. En los últimos años los magnetómetros ópticos se han convertido en los instrumentos más sensibles para medir los campos magnéticos de baja frecuencia, logrando sensibilidad de sub-femtotesla y superando dispositivos como los superconductores de interferencia cuántica (SQUID), y han encontrado aplicaciones en biomedicina, geofísica, ciencia espacial, así como en varias pruebas de física fundamental. Otra técnica emergente es la espectroscopía de ruido de espin (SNS), que permite determinar las propiedades físicas de un sistema de espin sin perturbarlo por medio de su espectro de potencia de ruido. En la última década, los avances tecnológicos como analizadores de espectro en tiempo real y detectores limitados por el ruido de disparo de fotón han permitido mejoras en la sensibilidad de detección de ruido de spin que conduce a una amplia gama de aplicaciones tanto en la física del estado sólido como en la física atómica. El objetivo principal de esta tesis es responder a una cuestión pendiente e importante: si la "luz comprimida" puede mejorar la sensibilidad de los sensores atómicos en condiciones óptimas para la sensibilidad, típicamente en un régimen de alta densidad debido a la ventaja estadística de utilizar más átomos. En primer lugar, se describe el diseño, construcción y caracterización de un nuevo aparato experimental versátil para el estudio de la espectroscopia atómica con luz comprimida dentro de un régimen de alta densidad (n=¿10¿^12 ¿cm¿^(-3)) y bajo nivel de ruido magnético (¿pT/vHz). El nuevo sistema experimental se combina con una fuente existente de luz comprimida en polarización, basado en el proceso de conversión paramétrica espontánea descendente (SPDC) en un cristal no lineal, que es el medio activo de un oscilador paramétrico óptico. En segundo lugar, se presenta la primera demostración experimental de espectroscopía de espin de Rubidio, en abundancia natural, mejorada a través de la compresión en polarización de la luz de prueba. Se encontró que la entrada de 3.0 dB de luz comprimida mejora la relación señal-ruido de 1.5 dB a 2.6 dB en el intervalo combinado (potencia óptica)¿(densidad atómica) de (0.5 mW to 4.0 mW) ¿ (1.5׿10¿^12 ¿cm¿^(-3) to 1.3׿10¿^13 ¿cm¿^(-3)), que cubre rangos utilizados en los experimentos optimizados de espectroscopía de ruido de espin. También mostramos que la luz comprimida mejora el equilibrio entre la sensibilidad estadística y efectos de ampliación de la resonancia. A continuación, se introduce un nuevo modelo teórico con la definición de un límite cuántico estándar (SQL) para la espectroscopía de ruido detectado ópticamente, identificado como un límite a la covarianza de los parámetros estimados mediante el ajuste de los espectros de potencia de ruido. Probamos el modelo para la espectroscopia de ruido de espin en abundancia natural de rubidio y demostramos el rendimiento experimental de la espectroscopia de ruido al límite cuántico estándar para una haz coherente y por debajo del SQL para una haz de luz comprimida en polarización. Por último, se presenta un magnetómetro óptico basado en rotación óptica modulada en amplitud (AMOR), utilizando una celda de vapor de 85Rb, que logra sensibilidad a la temperatura ambiente de 70 fT/vHz a 7.6 µT y demostramos su limite de ruido de disparo de fotón (SNL) en el intervalo de 5 µT a 75 µT. Si bien no se utilizaron recursos cuánticos de la luz en este segundo experimento, la combinación de la mejor sensibilidad, en la clase de los magnetómetros escalares de temperatura ambiente, y con operación al limite de ruido de disparo hace que el sistema sea un candidato prometedor para la aplicación de luz comprimida a un magnetómetro óptico optimizado con mejor sensibilidad en la clase
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Parker, Ryan Charles. "A loss resilient entanglement swapping protocol using non-classical states of light". Thesis, University of York, 2018. http://etheses.whiterose.ac.uk/22822/.
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Distributing and sharing entanglement at a distance is a key ingredient in many future quantum communication protocols, however entanglement is a fragile resource and can break down upon interacting with the environment. Within this thesis we present two possible entanglement swapping protocols, and show that these protocols are resilient to small levels of photonic losses. We propose the use of these protocols in quantum communication schemes that require shared entangled qubits, in the form of a Bell state. The input states to our proposed protocols are hybrid entangled states, which are discrete-variable and continuous-variable entangled states. We use the vacuum and single photon Fock state as our discrete half, which is stationary in our entanglement swapping protocol, whereas the continuous variable half is modelled as travelling through lossy optical fibre before being measured. The first protocol uses coherent states in a superposition as propagating modes in our entanglement swapping setup, whereas the second, more complicated, protocol uses superposed cat states. We model photonic losses by applying a beam-splitter of transmission T to our propagating continuous variable modes, along with an input vacuum state. We also model the more realistic circumstance in which the losses in these two continuous variable modes are not equal. We then detect these continuous variable modes using a vacuum projective measurement and balanced homodyne detection. We also investigate homodyne measurement imperfections and non-ideal outcomes, as well as success probabilities of these measurement schemes. We calculate the entanglement negativity and linear entropy of our final two qubit state, as well as fidelity against the |\Phi^+ > Bell state in the coherent state protocol, and a phase-rotated |\Phi^+(\alpha)> Bell state in the cat state regime. We demonstrate that a small amount of loss mismatch does not destroy the overall entanglement, thus demonstrating the physical practicality of this protocol.
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Wu, Di Ph D. Massachusetts Institute of Technology. "Spatiotemporal lifecycle assessment of the light-duty vehicle fleet of United States". Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/120265.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2018.Cataloged from PDF version of thesis.
Includes bibliographical references.
Greenhouse gas (GHG) emission generated by vehicular transportation is one of the most significant challenges facing the world. Automotive manufacturers are actively pursuing technological solutions, such as electrification and light-weighting, to mitigate the emission burdens. However, it remains challenging to understand the actual emission payoff of these technologies, since the real-world driving context and characteristics vary greatly. The recent rapid growth of a new mobility behavior, ride-hailing, has also raised important questions for urban transportation and sustainability, largely because the net environmental impact of ride-hailing services is similarly challenging to assess. In this dissertation, I develop techniques aimed at treating these complex, context-dependent assessment challenges and address two questions: 1) What is the cost optimal technology portfolio required to achieve the environmental targets for the light-duty vehicle fleets? 2) How do the emerging ride-hailing services influence the carbon footprints of light-duty vehicles? This thesis presents my work on the first regionally explicit (county-level) lifecycle assessment of two technologies directed at mitigating the GHG emissions of light-duty vehicles in the U.S. - lightweighting and electrification. Regional differences in climate, electric grid mix, and driving patterns compound to produce a significant regional heterogeneity in the GHG benefits of electrification. We show that lightweighting further accentuates these regional differences. I then expand the scope to incorporate the dynamic evolution of the light-duty vehicle fleets. Through evaluating the lifecycle emission and ownership cost, I identify the most cost-effective technology portfolios of the county-level vehicle fleets that meet specified environmental targets (as the fleet evolves over time/over the course of fleet evolution?). Finally, to tackle the second question of changing modes of vehicle use, I developed the first elaborate, systematic and data-centric study on the environmental sustainability of ride-hailing in major American cities. Through the use of increasingly available large datasets describing vehicle trips within urban areas, I demonstrated that, while ride-sharing leads to positive environmental impacts, the rebound arising from shifts away from mass transit toward ride-hailing engenders substantial negative impact. Results show that the environmental impacts of ride-hailing are strong functions of urban context and vehicle technology, and ride-hailing is unlikely to achieve net environmental benefits without regulatory intervention. These findings fill an important gap in people's understanding of the advanced automotive technologies and the emerging mobility behavior from sustainability perspective, and shed light on the recent upheaval that vehicular transportation has caused across the United States.
by Di Wu.
Ph. D.
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Kocsis, Alexander (Sacha) Julien. "Controlling Non-Classical States of Light: Experimental Techniques in Quantum Information Science". Thesis, Griffith University, 2014. http://hdl.handle.net/10072/367240.
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The key task of transmitting quantum states encompasses a diverse array of tech- niques and applications. This thesis presents experimental work in optical quantum information science, focused on strategies for transmitting quantum states with high fidelity and security. The majority of the work in this thesis is in photonic quantum information science, although one experiment used continuous–variable states.
In the first experiment, the noiseless amplification of a photon polarisation qubit was realised, using delocalised single photon ancilla states and two single–mode amplification stages operating coherently. Artificial loss was applied to a single photon, to simulate a loss in a long–distance quantum transmission channel, and for the highest gain setting that was investigated, the qubit amplifier achieved a five–fold increase in transmission fidelity.
In the second experiment, linear optical techniques for distributing mode entangle- ment in a quantum network were studied. Quantum networks are based on a series of nodes, potentially separated by significant distances, and connected via quantum repeaters. Different quantum repeater architectures have been proposed, but they all include embedded distillation stages, which are based on linear optical techniques. We simulate two distinct quantum repeater scenarios, using different configurations of an entanglement swapping stage, a noiseless single–mode amplification stage, and loss. The performance of the amplification stage in overcoming the loss is characterised in both configurations. Significant distillation of mode entanglement is achieved in one configuration, and an increase in mode coherence is achieved in the other configuration.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Biomolecular and Physical Sciences
Science, Environment, Engineering and Technology
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Bora, Vaibhav Joga Singh. "Photon Statistics in Scintillation Crystals". Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/577317.
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Scintillation based gamma-ray detectors are widely used in medical imaging, high-energy physics, astronomy and national security. Scintillation gamma-ray detectors are field-tested, relatively inexpensive, and have good detection efficiency. Semi-conductor detectors are gaining popularity because of their superior capability to resolve gamma-ray energies. However, they are relatively hard to manufacture and therefore, at this time, not available in as large formats and much more expensive than scintillation gamma-ray detectors. Scintillation gamma-ray detectors consist of: a scintillator, a material that emits optical (scintillation) photons when it interacts with ionization radiation, and an optical detector that detects the emitted scintillation photons and converts them into an electrical signal. Compared to semiconductor gamma-ray detectors, scintillation gamma-ray detectors have relatively poor capability to resolve gamma-ray energies. This is in large part attributed to the "statistical limit" on the number of scintillation photons. The origin of this statistical limit is the assumption that scintillation photons are either Poisson distributed or super-Poisson distributed. This statistical limit is often defined by the Fano factor. The Fano factor of an integer-valued random process is defined as the ratio of its variance to its mean. Therefore, a Poisson process has a Fano factor of one. The classical theory of light limits the Fano factor of the number of photons to a value greater than or equal to one (Poisson case). However, the quantum theory of light allows for Fano factors to be less than one. We used two methods to look at the correlations between two detectors looking at same scintillation pulse to estimate the Fano factor of the scintillation photons. The relationship between the Fano factor and the correlation between the integral of the two signals detected was analytically derived, and the Fano factor was estimated using the measurements for SrI₂:Eu, YAP:Ce and CsI:Na. We also found an empirical relationship between the Fano factor and the covariance as a function of time between two detectors looking at the same scintillation pulse. This empirical model was used to estimate the Fano factor of LaBr₃:Ce and YAP:Ce using the experimentally measured timing-covariance. The estimates of the Fano factor from the time-covariance results were consistent with the estimates of the correlation between the integral signals. We found scintillation light from some scintillators to be sub-Poisson. For the same mean number of total scintillation photons, sub-Poisson light has lower noise. We then conducted a simulation study to investigate whether this low-noise sub-Poisson light can be used to improve spatial resolution. We calculated the Cramér-Rao bound for different detector geometries, position of interactions and Fano factors. The Cramér-Rao calculations were verified by generating simulated data and estimating the variance of the maximum likelihood estimator. We found that the Fano factor has no impact on the spatial resolution in gamma-ray imaging systems.
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Ast, Stefan [Verfasser]. "New approaches in squeezed light generation : quantum states of light with GHz squeezing bandwidth and squeezed light generation via the cascaded Kerr effect / Stefan Ast". Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover (TIB), 2015. http://d-nb.info/1072062666/34.
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Farrera, Soler Pau. "A versatile source of light-matter quantum states based on laser-cooled atoms". Doctoral thesis, Universitat Politècnica de Catalunya, 2018. http://hdl.handle.net/10803/663094.
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Quantum information is a fascinating field that studies situations in which information is encoded as quantum states. This encoding is affected by quantum physical effects (such as superposition or entanglement) and its study has led to exciting discoveries from both fundamental and applied perspectives. An interesting system within this field is a quantum light-matter interface, able to interface quantum states encoded in light and those encoded in matter. These systems can combine the long distance transmission advantage of photonic states with the storage and processing capabilities of matter states.
The main goal of this thesis was to develop a quantum light-matter interface able to distribute the photonic state to other interfaces based on different platforms. This versatility could open new possibilities that combine the advantages of the different platforms. In this thesis we studied the challenges to make these hybrid connections possible and we performed two examples of such connections.
Our quantum light-matter interface is based on a cloud of Rubidium atoms that are laser-cooled in a magneto-optical trap. We operate the atomic system using the Duan-Lukin-Cirac-Zoller scheme in order to generate pairs consisting on a single photon and an atomic collective spin excitation (so-called spin-wave). Spin-waves can later be mapped efficiently into a second single photon, which allows for synchronization capabilities. We use this scheme to generate different types of quantum states, such as heralded on-demand single photons and photonic qubits, photon-photon correlated states, or entanglement between photonic and atomic qubits.
Firstly, we studied two capabilities needed in order to perform the mentioned hybrid connections: the frequency and temporal tunability of the photonic states. In the first one we studied the frequency conversion of the single photons paired with spin-waves in the atomic medium. We could convert their wavelength from 780 nm to 1550 nm using a nonlinear crystal waveguide, while still showing quantum statistics of the field. In the second one we showed a temporal tunability of the single photons with durations ranging from around 10 ns to 10 us. The studied statistics of the fields indicate that the photons are close to Fourier-transform-limited, allowing for photon bandwidth tunability.
In the third work we studied the generation of a light-matter entangled state in which the photonic state is encoded as a time-bin qubit. Two key ingredients enabled this experiment: a magnetic-field-induced atomic dephasing that allows to create spin-waves in two distinguishable temporal qubit modes, and largely imbalanced Mach-Zehnder interferometers that enabled the qubit analysis. Photonic time-bin encoding has the advantages of low decoherence in optical fibers and direct suitability for frequency conversion.
Finally, we took advantage of these studied capabilities in order to transfer photonic quantum states generated by our laser-cooled atomic system to two different types of light-matter interfaces. The first one was a laser-cooled Rubidium cloud able to transfer single photons into Rydberg excitations. We showed that the quantum statistics of our photonic fields are preserved after the Rydberg storage, which represents a first step for future studies of quantum nonlinear effects using the long range Rydberg interaction. The second one was a crystal doped with Praseodymium ions. In this work the photonic quantum state transfer happened between systems with different atomic species, being a truly hybrid example that was enabled by quantum frequency conversion.
These results show a quantum light-matter interface where the properties of the photonic states can be tuned for an optimal interaction with other matter platforms. The proof-of-principle photonic quantum state transfers to the Rydberg and doped-crystal systems open the way to study new experiments that combine advantages of different platforms.La informació quàntica estudia situacions en les que la informació està codificada en estats quàntics. Aquesta codificació és afectada per efectes de la fisca quàntica (com ara superposició o entrellaçament) i el seu estudi ha portat a descobriments i noves aplicacions fascinants. Uns sistemes interessants dins d'aquest camp son les interfícies quàntiques de llum-matèria, les quals interconnecten estats quàntics codificats en llum i en matèria. Aquests sistemes combinen els avantatges dels estats fotònics (bona transmissió a llarga distància) amb els dels estats en matèria (bon emmagatzematge i processament). L'objectiu principal de la tesis era desenvolupar una interfície llum-matèria quàntica que pogués distribuir l'estat fotònic a altres interfícies basades en altres plataformes. Aquesta versatilitat podria obrir noves possibilitats que combinen els avantatges de les diferents plataformes. En aquesta tesis hem estudiat les dificultats que apareixen en aquestes connexions híbrides i hem realitzat dos exemples d'aquestes connexions. La nostra interfície llum-matèria quàntica està basada en un núvol d'àtoms de Rubidi que estan refredats en una trampa magneto-òptica. Operem aquest sistema atòmic utilitzant l'esquema Duan-Lukin-Cirac-Zoller per tal de generar parelles que consisteixen en un fotó individual i una excitació atòmica d'espín col·lectiva (anomenada ona-d'espín). Nosaltres utilitzem aquest esquema per tal de generar diferents tipus d'estats quàntics, com ara fotons individuals o qubits fotònics, estats correlacionats de fotó-fotó o entrellaçament entre qubits fotònics i atòmics. Primerament vam estudiar dues capacitats que es necessiten per tal de fer possible les connexions híbrides mencionades: la flexibilitat de la freqüència i el perfil temporal dels estats fotònics. En el primer vam estudiar la conversió de la freqüència dels fotons individuals aparellats amb ones-d'espín en el medi atòmic. Vam poder convertir la seva longitud d'ona de 780nm a 1552nm utilitzant una guia d'ones amb un cristall no-lineal. En el segon vam mostrar la flexibilitat en la duració temporal de fotons individuals amb duracions que van de 10 ns a 10 ns. Les propietats estudiades dels fotons indiquen que el seu espectre està limitat per la transformada de Fourier, la qual cosa permet la flexibilitat del seu espectre. En el tercer treball vam estudiar la generació d'un estat entrellaçat entre llum i matèria en el que l'estat fotònic està codificat en un time-bin qubit. Dos ingredients claus van permetre aquest experiment: un desfasament atòmic induït per un camp magnètic que permet crear ones-d’espín en dos modes temporals distingibles, i interferòmetres de Mach-Zehnder que van permetre l’anàlisi dels qubits. La codificació fotònica de time-bin té els avantatges de baixa decoherència en fibres òptiques i una compatibilitat directa per efectuar conversió de freqüència. Finalment, vam aprofitar aquestes capacitats estudiades per tal de transferir estats quàntics fotònics cap a dos tipus diferents d'interfícies llum matèria. La primera va ser una altre núvol fred d’àtoms de Rubidi en el que és possible transferir fotons individuals cap a excitacions de Rydberg. Aquest experiment representa el primer pas per a futurs estudis d'efectes quàntics no-lineals utilitzant les interaccions Rydberg de llarga distància. Els segon va ser un cristall dopat amb ions de Praseodimi. En aquest treball la transferència de l'estat quàntic va passar entre sistemes amb diferents espècies atòmiques, sent un veritable exemple híbrid fet possible per la conversió de freqüència quàntica. Aquests resultats mostren una interfície llum-matèria quàntica en la que les propietats dels estats fotònics poden ser optimitzades per obtenir una interacció òptima amb altres plataformes materials. Les transferències fotòniques d'estats quàntics als sistemes de Rydberg i de cristalls obren la porta a l'estudi de nous experiments que combinin els avantatges de les diferents plataformes.
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DiGuglielmo, James [Verfasser]. "On the experimental generation and characterization of entangled states of light / James DiGuglielmo". Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover, 2010. http://d-nb.info/1008525707/34.
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Arndt, Daniel. "Light-Cone Quark Model Analysis ofPseudoscalar and Vector Mesons for Radially Excited States". NCSU, 1999. http://www.lib.ncsu.edu/theses/available/etd-19990518-132243.
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We present a relativistic constituent quark model to analyze the mass spectrum and hadronic properties of radially excited u and d quark sector mesons.Using a simple Gaussian function as a trial wave function for the variational principle togetherwith a QCD motivated Hamiltonian, including not only the Coulomb and confiningpotential but also a relativistic corrected hyperfine interaction term, we obtain the mass spectrum consistent with the experimental data. To do the same for several observables such as decay constants and form factors it seems necessary to include bothDirac and Pauli form factors on the level of constituentquarks. Taking into account these quark form factorswe thus present the generalized formulas for the rho mesondecay constant and the rho meson form factors as well asthe $\pi\gamma$ transition form factor.We alsopredict several hadronic properties for the radiallyexcited states.
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Fearnside, Andrew Simon. "Dressed autoionising states and light-induced continuum structures in an intense laser field". Thesis, Durham University, 1996. http://etheses.dur.ac.uk/5225/.
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Results are presented for Floquet calculations of photodetachment rates from a one-dimensional model atom irradiated by intense laser light. Light-induced quasibound states are found to originate from the movement of poles of the multichannel scattering matrix on the Riemann energy surface. The appearance of new bound states of the negative Hydrogen ion, recently predicted, is related to the motion of resonance poles that correspond to autoionising states in the absence of the field. A number of pole trajectories, leading to light-induced states, are discussed for the one-dimensional model atom. The Floquet method allows one to represent the wave function of a quantum system in a laser field, as an infinite sum of harmonic basis functions. In any practical calculation this infinite sum must be truncated. The consequences of representing the wave function, via the Floquet method, by a finite sum of harmonics is addressed. An illustration of these consequences is made by way of a number of representative calculations performed on a one-dimensional model atom. Results are presented of calculations performed to determine the influence of a laser field, of low to moderate intensity, upon the partial and total photodetachment rates of the negative Hydrogen ion, H(^-). Using the R-matrix Floquet method, a study is undertaken into the detachment of an electron from the ion, via multiphoton transitions through one of several autodetaching resonances of the ion. The discussion focuses on the influence of the laser field upon auto detaching pathways. It is found that the laser may induce structure into the continuum that does not exist in the absence of the laser field, or, conversely, may suppress field-free structure. In the latter case, the suppression of structure is related to the appearance of laser-induced degeneracies.
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Gavin, Elizabeth Jane Ogle. "Bound states of heavy and light quarks in the framework of quantum chromodynamics". Master's thesis, University of Cape Town, 1985. http://hdl.handle.net/11427/14576.
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Bibliography: leaves 53-55.The spectra of the D, F, B and E mesons have been calculated using the MIT bag model together with a static potential related to the Fourier transform of the "dressed" gluon propagator. The heavy quark has been assumed to coincide with the centre of the bag, while the Light antiquark was treated relativistically using the Dirac equation. The spectra obtained are compared with experimental data as well as with the results of other models of these Qq mesons. The ratio mb/mc obtained in the fit to experimentally known states is compared with the result expected from the hyperfine splitting of the D and B mesons. It appears that tris ratio is model dependent. More experimental data are required to further evaluate the validity of this model.
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Suess, C. J. "Quantum chemical calculations of the excited states of porphyrins". Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/48422/.
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The development of optical multidimensional spectroscopic techniques has opened up new possibilities for the study of biological processes. Ultrafast two-dimensional ultraviolet spectroscopy experiments have determined the rates of tryptophan → heme electron transfer and excitation energy transfer for the two tryptophan residues in myoglobin. Here we show that accurate prediction of these rates can be achieved using Marcus theory in conjunction with time dependent density functional theory (TDDFT). Key intermediate residues between the donor and acceptor are identified, and in particular the residues Val68 and Ile75 play a critical role in calculations of the electron coupling matrix elements. Our calculations demonstrate how small changes in structure can have a large effect on the rates, and show that the different rates of electron transfer are dictated by the distance between the heme and tryptophan residues, while for excitation energy transfer the orientation of the tryptophan residues relative to the heme is important. The absorption and fluorescence spectroscopy of a series of porphyrin based systems have been studied. The range of systems has been selected in order to investigate the influence of both the electronic and geometric configuration on the photophysical properties. The origin of the bathochromic shift in the absorption and fluorescence spectra of substituted porphyrins is attributed to both steric distortions of the ring and electronic effects of the substituents. Three DFT based approaches have been used to model and calculate these properties. The approach using the maximum overlap method (MOM) predicted the largest discrepancy from Excited States of Porphyrins experimental results whilst TDDFT calculated shifts within 0.05 eV of experimental values. Finally a third method labelled as a ‘hybrid’ approach has been used, where the MOM is employed to optimise excited state geometries and single point TDDFT calculations are used to evaluate the vertical excitation energies. This approach improves on the excitation energies predicted by the MOM but does not improve on the values that a full TDDFT calculation produced. However, this ‘hybrid’ approach is computationally less demanding. There is distinct trade-off between accuracy and feasibility of calculations, where this ‘hybrid’ method of MOM and TDDFT becomes beneficial and useful. High resolution spectra of both free base and metallocentred complexes of porphyrin are calculated for the Q band region. Calculations on the vibronic structure of porphyrin are performed using DFT and TDDFT. Both Franck–Condon (FC) and Herzberg–Teller (HT) approaches have been used to predict the frequency and intensity of vibronic bands in the simulated absorption spectra with respect to the S0 → S1 electronic transition as the summation of contributions from both schemes characterise the electronic transitions and provide a high resolution description of the Q-band. Chapter five shows that the first electronic transition into the singlet excited state is vibronically active in the Qx region of the absorption spectrum, in good agreement with experimental data. The HT scheme appears to have more significant contributions and provides more insight into resolving the vibrationally active area of the absorption spectra. HT contributions to the electronic transition dipole moments are essential to assign the weak vibrational transitions and reproduce the experimental spectral profile. In order to provide a detailed account of the vibronic structure it is necessary to assign the vibrational transitions using both HT and FC schemes. The importance of theoretical calculations are highlighted here and can help the general understanding of the photophysical properties of porphyrins.
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Dodd, Thomas G. "Development of a three dimensional terrain display for a light infantry platoon combat model". Thesis, Monterey, California : Naval Postgraduate School, 1990. http://handle.dtic.mil/100.2/ADA247994.
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Thesis (M.S. in Systems Technology (Command, Control, and Communication))--Naval Postgraduate School, June 1990.Thesis Advisor(s): Parry, Samuel H. Second Reader: Hoffman, James C. "June 1990." Description based on signature page as viewed on October 21, 2009. Page 21 is missing and not attainable. DTIC Identifier(s): Combat models. Author(s) subject terms: Three dimensional graphics display, combat model, DYNTACS terrain representation. Includes bibliographical references (p. 134-135). Also available online.
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Tesfamariam, Alem Mebrahtu. "Fluctuations in quantum optical systems from Bose-Einstein condensates to squeezed states of light /". [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=983242283.
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Lemieux, Samuel. "Tailoring the Modal Structure of Bright Squeezed Vacuum States of Light via Selective Amplification". Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34920.
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The bright squeezed vacuum state of light is a macroscopic nonclassical state found at the output of a strongly pumped unseeded travelling-wave optical parametric amplifier. It has been applied to quantum imaging, quantum communication, and phase supersensitivity, to name a few. Bright squeezed states are in general highly multimode, while most applications require a single mode. We separated two nonlinear crystals in the direction of propagation of the pump in order to narrow the angular spectrum down to a nearly-single angular mode. We observed noise reduction in the photon number difference between the two down-converted channels, which constitutes of proof of nonclassicality. By introducing a dispersive medium between the two nonlinear crystals, we were able to tailor the frequency spectrum of bright squeezed vacuum and to dramatically reduce the number of frequency modes down to 1.82 ± 0.02, bringing us closer to truly single-mode bright squeezed vacuum.
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Zhen, Bo Ph D. Massachusetts Institute of Technology. "Optical bound states in the radiation continuum : from topological charges to light-emission applications". Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/95849.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Physics, 2014.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 83-89).
Bound states in the continuum (BICs) are unusual solutions of wave equations describing light or matter: they are discrete and spatially bounded, but exist at the same energy as a continuum of states which propagate to infinity. In this thesis, we will explore optical BICs from different perspectives, including physical intuitions, fundamental theories, sample fabrications, experimental setups, and real-life applications. First, we demonstrate the existence of such exceptions realized in macroscopic two dimensional periodic photonic crystals slab. The reason for these special modes to completely decouple from the continuum of free-space modes is through mismatching their symmetries. Further, we distinguish these special non-degenerate states with quality factors as high as 10' that extend over 108 unit cells from other existing modes in the system. Then, we show BICs have profound implications in light-emission applications. When coupling these special states to emitters, we demonstrate greatly enhanced and strongly modulated spontaneous emission from organic molecules, due to the unique properties of BICs. Furthermore, these BICs enable lasing of organic molecules with threshold at least one order of magnitude lower than previous reported results. Third, we demonstrate a different kind of BICs: those are not protected by symmetry incompatibility. We experimentally demonstrate that light can be perfectly confined in a patterned dielectric slab, even though outgoing waves (symmetry compatible) are allowed in the surrounding medium. Such states exist stably in a general class of geometries where all of its radiation amplitudes vanish simultaneously due to destructive interference. Finally, we provide a fundamental understanding about the nature of BICs that unify both types of BICs. We also explain the robustness of them through their topological nature. We show that both types of BICs are vortex centers in the polarization direction of far-field radiation. The robustness of these BICs is due to the existence of conserved and quantized topological charges, defined by the winding number of the polarization vectors. Such charges can only be generated or annihilated by making large changes in the system parameters, and then only according to strict rules, which we derive and test numerically.
by Bo Zhen.
Ph. D.
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Arndt, Daniel. "Light-cone quark model analysis of pseudoscalar and vector mesons for radially excited states". Raleigh, NC : North Carolina State University, 1999. http://www.lib.ncsu.edu/etd/public/etd-3522131849921371/etd.pdf.
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McGuinness, Hayden James 1980. "The creation and frequency translation of single-photon states of light in optical fiber". Thesis, University of Oregon, 2011. http://hdl.handle.net/1794/11259.
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xiii, 164 p. : ill. (some col.)We explore the frequency translation of single-photon states of light and the creation of photon pairs by four-wave mixing in optical fiber. Frequency translation refers to changing the central frequency of a field, while photon pair creation refers to the creation of two individual photons at the same time. We demonstrate these effects in third-order nonlinear optical fiber. While both phenomena have previously been shown by three-wave mixing in second-order nonlinear media, there are compelling reasons to develop these tasks in third-order media. Most importantly, frequency translation in third-order material allows for the practical implementation of both small and large frequency shifts, while second-order material only practically allows for large shifts. Photon creation in third-order media often permits more flexible phase-matching conditions, allowing for the creation of a wider variety of quantum states than is often possible in second-order media. In our theoretical study of photon pair creation, we focus on the spectral correlations of the photon pairs. We pay particular attention to the creation of quantum states of high purity, where the photons are not spectrally correlated with one another. High purity photons are a requisite resource for several different quantum information processing applications, such as linear-optical quantum computing. We find that states with high purity can be realized with a minimal amount of spectral filtering. Experimentally, we study photon frequency translation in photonic crystal fiber. The central wavelength of the input photons was translated from 683 nm to 659 nm. We perform second-order intensity correlation measurements on both channels to demonstrate their quantum nature. This resulted in values of 0.21 ± 0.02 and 0.19 ± 0.05 for the 683-nm and 659-nm channels, respectively, demonstrating that those fields were dominated by their single-photon component. The efficiency at which the process occurred was 29 percent. Theoretically, we develop a Green function formalism to describe the translation process and develop a computational model to calculate the solution to the governing equations. Also, in a related experiment, we demonstrate classical frequency translation from 851 nm to 641 nm, a record translation in both wavelength and frequency, at an efficiency of 0.2 percent in a birefringent fiber.
Committee in charge: Dr. Daniel Steck, Chair; Dr. Michael Raymer, Advisor; Dr. Steven van Enk, Inside Member; Dr. Raghuveer Parthasarathy, Inside Member; Dr. Andrew Marcus, Outside Member
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Cooke, Jason Randolph. "Light front field theory calculation of deuteron properties /". Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/9662.
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