subject:(wigner)

1. Bougacha, Salma. High frequency oscillations in bounded elastic media : Oscillations haute fréquence en milieux élastiques bornés.

Degree: Docteur es, Mathématiques appliquées, 2010, Evry-Val d'Essonne

URL: http://www.theses.fr/2010EVRY0047

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Cette thèse est consacrée à l’étude haute fréquence de problèmes de Dirichlet et Neumann pour le système de l’élasticité. On y étudie le phénomène de… (more)

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Cette thèse est consacrée à l’étude haute fréquence de problèmes de Dirichlet et Neumann pour le système de l’élasticité. On y étudie le phénomène de réflexion au bord au moyen de deux techniques : la sommation de faisceaux gaussiens et les mesures de Wigner. Dans les chapitres 1 et 2, on commence par étudier le problème plus simple de l’équation des ondes scalaire à une vitesse. Sous certaines hypothèses sur les conditions initiales, on construit des solutions approchées par superposition de faisceaux gaussiens. La justification de l’asymptotique se fonde sur une estimation de normes de certains opérateurs intégraux à phases complexes. Pour des conditions initiales plus générales, on utilise les mesures de Wigner pour calculer la densité d’énergie microlocale. On calcule explicitement les transformées de Wigner d’intégrales de faisceaux gaussiens. Le comportement de la densité d’énergie microlocale de la solution exacte se déduit de celui établi pour la solution approchée. Dans le chapitre 3, on utilise les résultats établis pour les sommes infinies de faisceaux gaussiens pour construire une solution approchée pour les équations de l’élasticité et calculer sa densité d’énergie microlocale. L’existence de deux vitesses différentes dans le système de l’élasticité introduit de nouvelles difficultés qui sont traitées dans ce chapitre.

This thesis is devoted to the study of the high frequency Dirichlet and Neumann problems for the elasticity system. We study the reflection phenomenon at the boundary by means of two techniques: Gaussian beams summation and Wigner measures. In chapters 1 and 2, we start by studying the simpler problem of the scalar wave equation with one speed. Under some hypotheses on the initial conditions, we build an approximate solution by a Gaussian beams superposition. Justification of the asymptotics is based on norms estimate of some integral operators with complex phases. For more general initial conditions, we use Wigner measures to compute the microlocal energy density. We compute Wigner transforms of Gaussian beams integrals in an explicit way. The behaviour of the microlocal energy density for the exact solution is deduced from the one for the approximate solution. In chapter 3, we use the established results on infinite sums of Gaussian beams to build an approximate solution for the elasticity equations and to compute its microlocal energy density. We treat new difficulties arising from the existence of two different speeds in the elasticity system.

Advisors/Committee Members: Alexandre, Radjesvarane (thesis director), Akian, Jean-Luc (thesis director).

Subjects/Keywords: Mesure de Wigner

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APA (6^th Edition):

Bougacha, S. (2010). High frequency oscillations in bounded elastic media : Oscillations haute fréquence en milieux élastiques bornés. (Doctoral Dissertation). Evry-Val d'Essonne. Retrieved from http://www.theses.fr/2010EVRY0047

Chicago Manual of Style (16^th Edition):

Bougacha, Salma. “High frequency oscillations in bounded elastic media : Oscillations haute fréquence en milieux élastiques bornés.” 2010. Doctoral Dissertation, Evry-Val d'Essonne. Accessed January 22, 2021. http://www.theses.fr/2010EVRY0047.

MLA Handbook (7^th Edition):

Bougacha, Salma. “High frequency oscillations in bounded elastic media : Oscillations haute fréquence en milieux élastiques bornés.” 2010. Web. 22 Jan 2021.

Vancouver:

Bougacha S. High frequency oscillations in bounded elastic media : Oscillations haute fréquence en milieux élastiques bornés. [Internet] [Doctoral dissertation]. Evry-Val d'Essonne; 2010. [cited 2021 Jan 22]. Available from: http://www.theses.fr/2010EVRY0047.

Council of Science Editors:

Bougacha S. High frequency oscillations in bounded elastic media : Oscillations haute fréquence en milieux élastiques bornés. [Doctoral Dissertation]. Evry-Val d'Essonne; 2010. Available from: http://www.theses.fr/2010EVRY0047

University of Canterbury

2. Gillard, Adam Blake. Quantum Fields, Dark Matter, Elko Fields and Non-Standard Wigner Classes.

Degree: PhD, Physics, 2012, University of Canterbury

URL: http://dx.doi.org/10.26021/7443

► In this thesis we examine the Elko field dark matter candidate, its interactions, and possible theoretical origins. We discuss important areas in which Elko Field… (more)

▼ In this thesis we examine the Elko field dark matter candidate, its interactions, and possible theoretical origins. We discuss important areas in which Elko Field Theory is incomplete and propose what we consider to be the most natural ways of plugging the holes in the theory. The way we propose to plug these holes enables Elko fields to interact with Standard Model gauge quanta. Any possible Elko darkness may be then due to Elko non-locality. The possible existence of Elko gauge interactions constitutes a significant result in this thesis. We also explore how Elko quantum fields might arise on the state space. We show that the Elko field is not a quantum field in the sense of Weinberg and that the Elko field violates the symmetries of the Lorentz group; another significant result altering how we think about Elko Field Theory. We also show that subgroups of the Lorentz group do not give rise to Elko fields (or their VSR counterparts) on the state space. We also examine the non-standard Wigner classes and show that in the context of our most natural ways of plugging the holes present in Elko Field Theory, Elko fields do not arise there either. We also show that in one of the non-standard Wigner classes, under certain conditions, there can exist a local massive spin-1/2 quantum field Majorana type dark matter candidate that is a well-defined quantum field in the sense of Weinberg. We give the dynamics of this new quantum field and also specify under what conditions this quantum field can exist. We finish the thesis by exploring Elko fields and their left and right-handed components in the context of the Electroweak Theory, in a more speculative way. We take the general concept of mass dimension transmutation introduced for Classical Spinor Theory by J.M. Hoff da Silva and R. da Rocha and apply it to the state space in the most natural way. We use this to derive a formula linking Dirac fields to the left-handed components of Elko fields and suggest the possibility of mass dimension transmutation being involved in electroweak interactions. Finally, we point out that although Elko fields cannot enter the Standard Model doublets, they can form their own doublets, the resulting symmetry currents of which can couple to the symmetry currents of the Standard Model.

Subjects/Keywords: quantum; fields; Wigner; Elko

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APA (6^th Edition):

Gillard, A. B. (2012). Quantum Fields, Dark Matter, Elko Fields and Non-Standard Wigner Classes. (Doctoral Dissertation). University of Canterbury. Retrieved from http://dx.doi.org/10.26021/7443

Chicago Manual of Style (16^th Edition):

Gillard, Adam Blake. “Quantum Fields, Dark Matter, Elko Fields and Non-Standard Wigner Classes.” 2012. Doctoral Dissertation, University of Canterbury. Accessed January 22, 2021. http://dx.doi.org/10.26021/7443.

MLA Handbook (7^th Edition):

Gillard, Adam Blake. “Quantum Fields, Dark Matter, Elko Fields and Non-Standard Wigner Classes.” 2012. Web. 22 Jan 2021.

Vancouver:

Gillard AB. Quantum Fields, Dark Matter, Elko Fields and Non-Standard Wigner Classes. [Internet] [Doctoral dissertation]. University of Canterbury; 2012. [cited 2021 Jan 22]. Available from: http://dx.doi.org/10.26021/7443.

Council of Science Editors:

Gillard AB. Quantum Fields, Dark Matter, Elko Fields and Non-Standard Wigner Classes. [Doctoral Dissertation]. University of Canterbury; 2012. Available from: http://dx.doi.org/10.26021/7443

3. Lopez, Matthias Paul. Test expérimental de l’universalité de la transition d’Anderson avec des atomes froids : indépendance de l’exposant critique ν face aux détails microscopiques : Experimental test of the universality of the Anderson transition with cold atoms : independence of the critical exponent ν to the microscopic details.

Degree: Docteur es, Optique et Lasers, Physico-Chimie, Atmosphère, 2012, Université Lille I – Sciences et Technologies

URL: http://www.theses.fr/2012LIL10048

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En physique du solide, l’étude des effets du désordre a mené à la découverte d’une transition de phase. A faible désordre le solide est conducteur.… (more)

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En physique du solide, l’étude des effets du désordre a mené à la découverte d’une transition de phase. A faible désordre le solide est conducteur. A fort désordre ce dernier devient isolant. Cette dernière porte le nom de “transition d’Anderson” ou encore de “transition métal-isolant”. Elle peut être caractérisée par un exposant critique ν. Il est prédit théoriquement que sa valeur est universelle, autrement dit, qu’elle n’est pas dépendante des détails microscopiques caractérisant le désordre, mais seulement des symétries satisfaites par le hamiltonien. La réalisation expérimentale d’un tel système est délicate. Des effets de décohérence trop nombreux viennent fausser la mesure de l’exposant critique. Pour contourner ces difficultés, nous réalisons un rotateur frappé avec des atomes froids. La dynamique quantique de ce système est connue pour être la même que celle de l’électron dans un potentiel désordonné. Nous testons alors différents jeux de paramètres régissant le désordre microscopique, et montrons que l’exposant critique ν en est indépendant. Ainsi nous prouvons expérimentalement l’universalité de la transition, ainsi que son appartenance à une classe d’universalité : l’ensemble gaussien orthogonal. Nous détaillons par ailleurs un changement de taille dans le dispositif : la réalisation d’une onde stationnaire verticale et d’une détection vélocimétrique par temps de vol.

In solid state physics, the study of the effects of disorder led to the discovery of a phase transition. For weak disorder, the solid is a conductor, whereas for strong disorder it becomes an insulator. This is known as the “Anderson transition” or as the “metal-insulator transition”, and can be characterized by a critical exponent ν. It is theoretically predicted that this exponent’s value is universal, i.e., that it is not determined by the microscopic details, but only by the symmetries of the Hamiltonian.The experimental realization of such a system in condensed matter is rather difficult. Decoherence effects cannot neglected and affect critical exponent’s value. To circumvent this phenomenon, we use cold atoms to experimentally realize a kicked rotor. The quantum dynamics of such a system are known to mimic those of the solid state problem. We hence test different sets of parameters controlling the statistical properties of the disorder, and show that the critical exponent ν is independent. We hereby prove the universality of the transition, and determine experimentally its universality class : the Gaussian Orthogonal Ensemble. We will then detail an important change in the experimental setup : the installation of a vertical standing wave, and of a time-of-flight velocimetric detection.

Advisors/Committee Members: Szriftgiser, Pascal (thesis director), Garreau, Jean-Claude (thesis director).

Subjects/Keywords: Rotateur frappé; Ensembles de Wigner-Dyson; 530.474

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APA (6^th Edition):

Lopez, M. P. (2012). Test expérimental de l’universalité de la transition d’Anderson avec des atomes froids : indépendance de l’exposant critique ν face aux détails microscopiques : Experimental test of the universality of the Anderson transition with cold atoms : independence of the critical exponent ν to the microscopic details. (Doctoral Dissertation). Université Lille I – Sciences et Technologies. Retrieved from http://www.theses.fr/2012LIL10048

Chicago Manual of Style (16^th Edition):

Lopez, Matthias Paul. “Test expérimental de l’universalité de la transition d’Anderson avec des atomes froids : indépendance de l’exposant critique ν face aux détails microscopiques : Experimental test of the universality of the Anderson transition with cold atoms : independence of the critical exponent ν to the microscopic details.” 2012. Doctoral Dissertation, Université Lille I – Sciences et Technologies. Accessed January 22, 2021. http://www.theses.fr/2012LIL10048.

MLA Handbook (7^th Edition):

Lopez, Matthias Paul. “Test expérimental de l’universalité de la transition d’Anderson avec des atomes froids : indépendance de l’exposant critique ν face aux détails microscopiques : Experimental test of the universality of the Anderson transition with cold atoms : independence of the critical exponent ν to the microscopic details.” 2012. Web. 22 Jan 2021.

Vancouver:

Lopez MP. Test expérimental de l’universalité de la transition d’Anderson avec des atomes froids : indépendance de l’exposant critique ν face aux détails microscopiques : Experimental test of the universality of the Anderson transition with cold atoms : independence of the critical exponent ν to the microscopic details. [Internet] [Doctoral dissertation]. Université Lille I – Sciences et Technologies; 2012. [cited 2021 Jan 22]. Available from: http://www.theses.fr/2012LIL10048.

Council of Science Editors:

Lopez MP. Test expérimental de l’universalité de la transition d’Anderson avec des atomes froids : indépendance de l’exposant critique ν face aux détails microscopiques : Experimental test of the universality of the Anderson transition with cold atoms : independence of the critical exponent ν to the microscopic details. [Doctoral Dissertation]. Université Lille I – Sciences et Technologies; 2012. Available from: http://www.theses.fr/2012LIL10048

Leiden University

4. Sluijs, Leendert van der. Naturalism and the Effectiveness of Mathematics in the Natural Sciences.

Degree: 2020, Leiden University

URL: http://hdl.handle.net/1887/87067

► As many philosophers and scientists have noticed, the way in which mathematics is used in the natural sciences for describing and predicting natural phenomena is… (more)

Subjects/Keywords: naturalism; effectiveness of mathematics; natural sciences; Wigner

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APA (6^th Edition):

Sluijs, L. v. d. (2020). Naturalism and the Effectiveness of Mathematics in the Natural Sciences. (Masters Thesis). Leiden University. Retrieved from http://hdl.handle.net/1887/87067

Chicago Manual of Style (16^th Edition):

Sluijs, Leendert van der. “Naturalism and the Effectiveness of Mathematics in the Natural Sciences.” 2020. Masters Thesis, Leiden University. Accessed January 22, 2021. http://hdl.handle.net/1887/87067.

MLA Handbook (7^th Edition):

Sluijs, Leendert van der. “Naturalism and the Effectiveness of Mathematics in the Natural Sciences.” 2020. Web. 22 Jan 2021.

Vancouver:

Sluijs Lvd. Naturalism and the Effectiveness of Mathematics in the Natural Sciences. [Internet] [Masters thesis]. Leiden University; 2020. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/1887/87067.

Council of Science Editors:

Sluijs Lvd. Naturalism and the Effectiveness of Mathematics in the Natural Sciences. [Masters Thesis]. Leiden University; 2020. Available from: http://hdl.handle.net/1887/87067

5. Bose, Amartya. Phase space and path integral approaches to quantum dynamics.

Degree: PhD, Chemistry, 2018, University of Illinois – Urbana-Champaign

URL: http://hdl.handle.net/2142/101548

► Exact quantum dynamical simulation of processes in highly coupled condensed phase reactions is extremely challenging. The work reported in this dissertation builds on top of… (more)

▼ Exact quantum dynamical simulation of processes in highly coupled condensed phase reactions is extremely challenging. The work reported in this dissertation builds on top of two different approaches. First, we present methods for calculating the multidimensional Wigner function. We start with a simple and approximate method which utilizes classical trajectories. This fits well with the subsequent classical propagation involved in a quasiclassical simulation. We use this method to study molecular Hamiltonians in both normal mode and Cartesian coordinates. Despite the simplicity of this method, there can be systems which are extremely anharmonic, where the method can be extremely slow to converge when there is no obviously good starting point. To overcome this problem, we propose a numerically exact path integral based method which can be systematically converged to any desired level of accuracy at increasing computational cost. Both these methods can be used with quantum classical simulation frameworks. Second, we present developments of rate theory methods. We extend the existing reactive flux rate methods to exact quantum classical methods. Two different initial conditions are proposed. If the transients are important, we show that the so-called "non-equilibrium" initial condition can help us unify the fast timescales as well as the long timescale dynamics governed by the rate. On the other hand, if the transients are of less importance, we propose a "near equilibrium" initial condition that can very effectively get rid of most of the transients. This initial condition captures the system-solvent interaction without increasing the complexity of the algorithm. Finally, we present a method of incorporating the concept of blip summation into the quantum-classical path integral (QCPI) method. This gives additional speedup on top of all the other advancements that make QCPI a very attractive method for doing exact quantum dynamics in condensed phase. Advisors/Committee Members: Makri, Nancy (advisor), Makri, Nancy (Committee Chair), Wagner, Lucas (committee member), Gruebele, Martin (committee member), Hirata, So (committee member).

Subjects/Keywords: quantum dynamics; path integrals; wigner distributions; rate

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APA (6^th Edition):

Bose, A. (2018). Phase space and path integral approaches to quantum dynamics. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/101548

Chicago Manual of Style (16^th Edition):

Bose, Amartya. “Phase space and path integral approaches to quantum dynamics.” 2018. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed January 22, 2021. http://hdl.handle.net/2142/101548.

MLA Handbook (7^th Edition):

Bose, Amartya. “Phase space and path integral approaches to quantum dynamics.” 2018. Web. 22 Jan 2021.

Vancouver:

Bose A. Phase space and path integral approaches to quantum dynamics. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2018. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/2142/101548.

Council of Science Editors:

Bose A. Phase space and path integral approaches to quantum dynamics. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2018. Available from: http://hdl.handle.net/2142/101548

Georgia Tech

6. Philip, Timothy. Error analysis of boundary conditions in the Wigner transport equation.

Degree: MS, Electrical and Computer Engineering, 2014, Georgia Tech

URL: http://hdl.handle.net/1853/54031

► This work presents a method to quantitatively calculate the error induced through application of approximate boundary conditions in quantum charge transport simulations based on the… (more)

Subjects/Keywords: Wigner transport equation; Boundary conditions; Error analysis

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APA (6^th Edition):

Philip, T. (2014). Error analysis of boundary conditions in the Wigner transport equation. (Masters Thesis). Georgia Tech. Retrieved from http://hdl.handle.net/1853/54031

Chicago Manual of Style (16^th Edition):

Philip, Timothy. “Error analysis of boundary conditions in the Wigner transport equation.” 2014. Masters Thesis, Georgia Tech. Accessed January 22, 2021. http://hdl.handle.net/1853/54031.

MLA Handbook (7^th Edition):

Philip, Timothy. “Error analysis of boundary conditions in the Wigner transport equation.” 2014. Web. 22 Jan 2021.

Vancouver:

Philip T. Error analysis of boundary conditions in the Wigner transport equation. [Internet] [Masters thesis]. Georgia Tech; 2014. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/1853/54031.

Council of Science Editors:

Philip T. Error analysis of boundary conditions in the Wigner transport equation. [Masters Thesis]. Georgia Tech; 2014. Available from: http://hdl.handle.net/1853/54031

7. Kakofengitis, Dimitris. Wigner-current in one-dimensional bound-state systems.

Degree: PhD, 2019, University of Hertfordshire

URL: http://hdl.handle.net/2299/21815

► The behaviour of classical systems is characterised by their phase portraits; the collections of their trajectories. In quantum mechanics phase portraits are still considered impossible… (more)

▼ The behaviour of classical systems is characterised by their phase portraits; the collections of their trajectories. In quantum mechanics phase portraits are still considered impossible to compute due to the complexity of quantum trajectories arising from the introduction of the quantum correction terms. Instead, in this thesis, we identify the Wigner current (the rate of flow per unit area of the Wigner distribution), as the quantum analogue of the classical phase-space current, and through Wigner current's fieldline portraits we show that it reveals hidden features of quantum dynamics and extra complexity. In our analysis, we focus on the simplest, most intuitive, and analytically accessible aspects of the Wigner current. We investigate its features for weakly-anharmonic weakly-excited bound-states of time-reversible one-dimensional quantum-mechanical systems. We establish that weakly-anharmonic potentials can be grouped into three distinct classes: hard, soft, and odd. We stress connections between each other and the harmonic case. We show that their Wigner current fieldline portraits can be characterised by the Wigner current's discrete stagnation points, how these arise and how a quantum system's dynamics is constrained by the stagnation points' topological charge conservation. We additionally demonstrate the conceptual power of the Wigner current by addressing some confusion found in the literature. We also stress the usefulness of the integral form of Wigner's representation as an alternative to the popular Moyal bracket. The integral form brings out the symmetries between momentum and position representations of quantum mechanics, is numerically stable, and allows us to perform some calculations using elementary integrals instead of Groenewold starproducts. The associated integral form of the Wigner current is used here in an elementary proof which shows that only systems up to quadratic in their potential fulfil Liouville's theorem of volume preservation in quantum mechanics.

Subjects/Keywords: Wigner Current; Quantum Phase Space; Quantum Physics

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APA (6^th Edition):

Kakofengitis, D. (2019). Wigner-current in one-dimensional bound-state systems. (Doctoral Dissertation). University of Hertfordshire. Retrieved from http://hdl.handle.net/2299/21815

Chicago Manual of Style (16^th Edition):

Kakofengitis, Dimitris. “Wigner-current in one-dimensional bound-state systems.” 2019. Doctoral Dissertation, University of Hertfordshire. Accessed January 22, 2021. http://hdl.handle.net/2299/21815.

MLA Handbook (7^th Edition):

Kakofengitis, Dimitris. “Wigner-current in one-dimensional bound-state systems.” 2019. Web. 22 Jan 2021.

Vancouver:

Kakofengitis D. Wigner-current in one-dimensional bound-state systems. [Internet] [Doctoral dissertation]. University of Hertfordshire; 2019. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/2299/21815.

Council of Science Editors:

Kakofengitis D. Wigner-current in one-dimensional bound-state systems. [Doctoral Dissertation]. University of Hertfordshire; 2019. Available from: http://hdl.handle.net/2299/21815

Miami University

8. Hyde, Jeffrey M. Characterizing the Entanglement in an Optical System.

Degree: MS, Physics, 2009, Miami University

URL: http://rave.ohiolink.edu/etdc/view?acc_num=miami1249671238

► Quasiprobability distributions, entanglement measures and correlation functions all give information about entanglement in a quantum state. We are studying these with the goal of using… (more)

Subjects/Keywords: Physics; quantum; Wigner

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APA (6^th Edition):

Hyde, J. M. (2009). Characterizing the Entanglement in an Optical System. (Masters Thesis). Miami University. Retrieved from http://rave.ohiolink.edu/etdc/view?acc_num=miami1249671238

Chicago Manual of Style (16^th Edition):

Hyde, Jeffrey M. “Characterizing the Entanglement in an Optical System.” 2009. Masters Thesis, Miami University. Accessed January 22, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=miami1249671238.

MLA Handbook (7^th Edition):

Hyde, Jeffrey M. “Characterizing the Entanglement in an Optical System.” 2009. Web. 22 Jan 2021.

Vancouver:

Hyde JM. Characterizing the Entanglement in an Optical System. [Internet] [Masters thesis]. Miami University; 2009. [cited 2021 Jan 22]. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=miami1249671238.

Council of Science Editors:

Hyde JM. Characterizing the Entanglement in an Optical System. [Masters Thesis]. Miami University; 2009. Available from: http://rave.ohiolink.edu/etdc/view?acc_num=miami1249671238

9. Julien, Grégory. Filtrage Stochastique et amélioration des performances des systèmes de positionnement d’engins sous-marins en milieu bruyant : Stochastic filter and underwater vehicule positioning systems improvement in noisy environment.

Degree: Docteur es, Sciences de l'ingénieur, 2012, Toulon

URL: http://www.theses.fr/2012TOUL0018

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Le positionnement d'un engin sous-marin s'appuie sur des systèmes dits "acoustiques". Ces derniers renseignent la position relative de l'engin immergé par rapport au navire support.… (more)

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Le positionnement d'un engin sous-marin s'appuie sur des systèmes dits "acoustiques". Ces derniers renseignent la position relative de l'engin immergé par rapport au navire support. Les performances de ces systèmes sont définies en termes de limite de portée et de précision. Le principe de ces systèmes repose sur les notions de distance-métrie et de goniométrie, qui s'appuient toutes deux sur l'estimation du temps de propagation et donc de la date d'arrivée du signal utile. Cela est classiquement réalisé par une opération de Compression d'Impulsion. Cette technique qui est largement utilisée dans les domaines du SONAR, RADAR et imagerie bio-médicale, repose sur une application sous-optimale du Filtrage Adapté. En effet, le Filtrage Adapté est une technique d’estimation ou de détection optimale lorsque le bruit et blanc et gaussien et lorsque le signal utile est déterministe, c’est-à-dire que le signal reçu est bien connu. Cependant, il est bien connu que dans le monde sous-marin, le bruit n’est pas blanc, et pas toujours gaussien. Aussi, le signal utile étant déformé soit par le milieu de propagation soit par des phénomènes physiques tels que l’effet Doppler, celui-ci n’est pas déterministe. On peut alors considérer que le bruit est coloré et que le signal utile est une réalisation d’un processus aléatoire. Ainsi, en vue d’étendre les hypothèse d’application de la Compression d’Impulsion classique, nous proposons de construire une nouvelle forme de Compression d’Impulsion basée sur l’utilisation du Filtrage Adapté Stochastique. En effet, ce dernier est une extension naturelle du Filtrage Adapté pour des bruits colorés et des signaux déterministes. Toutefois, le Filtrage Adapté Stochastique suppose que les signaux sont stationnaires au second ordre. Or, cela n’est pas toujours le cas pour le bruit en milieu marin, et cela n’est jamais le cas pour un signal modulé en fréquence tel que ceux utilisés par les systèmes de positionnement acoustiques. Ainsi, nous proposons une nouvelle technique de Compression d’Impulsion alliant les qualités du Filtrage Adapté Stochastique et celle des techniques Temps-Fréquence. Ces dernières, et en particulier la transformée de Wigner-Ville, permettent de contourner l’hypothèse de stationnarité imposée par le Filtrage Adapté Stochastique. D’autre part, en vue de contrer l’apparition d’interférences générées par ces techniques, nous développons ici une approche par « décomposition atomique » sur une base de DCT. Ainsi donc, ces trois années de thèse, ont donné naissance à de nouvelles méthodes de Compression d'Impulsion qui permettent d'améliorer les performances des systèmes de positionnement sous-marin.

The underwater vehicules positioning is based on acoustic systems. These systems provide us the relative position of the immersed submarine to the carrier ship. The systems performances are defined in terms of precision and slant range. The positioning systems use concepts like distance measurement and goniometry, both based on the Time Of Arrival estimation of the useful signal, which…

Advisors/Committee Members: Courmontagne, Philippe (thesis director).

Subjects/Keywords: Compression d'impulsion; Décomposition atomique; Wigner-Ville; Pulse compression; Atomic expension; Wigner-Ville

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APA (6^th Edition):

Julien, G. (2012). Filtrage Stochastique et amélioration des performances des systèmes de positionnement d’engins sous-marins en milieu bruyant : Stochastic filter and underwater vehicule positioning systems improvement in noisy environment. (Doctoral Dissertation). Toulon. Retrieved from http://www.theses.fr/2012TOUL0018

Chicago Manual of Style (16^th Edition):

Julien, Grégory. “Filtrage Stochastique et amélioration des performances des systèmes de positionnement d’engins sous-marins en milieu bruyant : Stochastic filter and underwater vehicule positioning systems improvement in noisy environment.” 2012. Doctoral Dissertation, Toulon. Accessed January 22, 2021. http://www.theses.fr/2012TOUL0018.

MLA Handbook (7^th Edition):

Julien, Grégory. “Filtrage Stochastique et amélioration des performances des systèmes de positionnement d’engins sous-marins en milieu bruyant : Stochastic filter and underwater vehicule positioning systems improvement in noisy environment.” 2012. Web. 22 Jan 2021.

Vancouver:

Julien G. Filtrage Stochastique et amélioration des performances des systèmes de positionnement d’engins sous-marins en milieu bruyant : Stochastic filter and underwater vehicule positioning systems improvement in noisy environment. [Internet] [Doctoral dissertation]. Toulon; 2012. [cited 2021 Jan 22]. Available from: http://www.theses.fr/2012TOUL0018.

Council of Science Editors:

Julien G. Filtrage Stochastique et amélioration des performances des systèmes de positionnement d’engins sous-marins en milieu bruyant : Stochastic filter and underwater vehicule positioning systems improvement in noisy environment. [Doctoral Dissertation]. Toulon; 2012. Available from: http://www.theses.fr/2012TOUL0018

10. Filippakis, Theodoros. ΘΕΩΡΙΑ ΤΟΥ ΦΑΣΙΚΟΥ ΧΩΡΟΥ ΤΗΣ ΜΗ-ΑΡΝΗΤΙΚΗΣ ΣΥΝΑΡΤΗΣΗΣ ΚΑΤΑΝΟΜΗΣ ΤΥΠΟΥ WIGNER.

Degree: 1986, University of Patras; Πανεπιστήμιο Πατρών

URL: http://hdl.handle.net/10442/hedi/0006

►

THE PROBLEM OF THE NON-NEGATIVE WIGNER DISTRIBUTION FUNCTION IS STUDIED. IT HASBEEN RECOGNIZED THAT THE PROBLEM IS RELATED TO SOME RECOGNIZED CORRESPODENSE RULE. THE NEW… (more)

Subjects/Keywords: ΕΞΙΣΩΣΗ BLOCH-WIGNER; ΕΞΙΣΩΣΗ WIGNER; ΘΕΩΡΗΜΑ WIGNER; ΚΑΝΟΝΕΣ ΑΝΤΙΣΤΟΙΧΙΑΣ; ΛΙΑ ΣΥΝΑΡΤΗΣΗ WIGNER; ΜΕΤΑΣΧΗΜΑΤΙΣΜΟΣ HUSIMI; ΝΕΟΙ ΤΕΛΕΣΤΕΣ WIGNER; BLOCH-WIGNER EQUATION; CORRESPONDENSES RULE; HUSIMI TRANSFORMATION; SMOOTHED WIGNER FUNCTION; WIGNER EQUATION; WIGNER OPERATORS; WIGNER'S THEOREME

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Filippakis, T. (1986). ΘΕΩΡΙΑ ΤΟΥ ΦΑΣΙΚΟΥ ΧΩΡΟΥ ΤΗΣ ΜΗ-ΑΡΝΗΤΙΚΗΣ ΣΥΝΑΡΤΗΣΗΣ ΚΑΤΑΝΟΜΗΣ ΤΥΠΟΥ WIGNER. (Thesis). University of Patras; Πανεπιστήμιο Πατρών. Retrieved from http://hdl.handle.net/10442/hedi/0006

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Filippakis, Theodoros. “ΘΕΩΡΙΑ ΤΟΥ ΦΑΣΙΚΟΥ ΧΩΡΟΥ ΤΗΣ ΜΗ-ΑΡΝΗΤΙΚΗΣ ΣΥΝΑΡΤΗΣΗΣ ΚΑΤΑΝΟΜΗΣ ΤΥΠΟΥ WIGNER.” 1986. Thesis, University of Patras; Πανεπιστήμιο Πατρών. Accessed January 22, 2021. http://hdl.handle.net/10442/hedi/0006.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Filippakis, Theodoros. “ΘΕΩΡΙΑ ΤΟΥ ΦΑΣΙΚΟΥ ΧΩΡΟΥ ΤΗΣ ΜΗ-ΑΡΝΗΤΙΚΗΣ ΣΥΝΑΡΤΗΣΗΣ ΚΑΤΑΝΟΜΗΣ ΤΥΠΟΥ WIGNER.” 1986. Web. 22 Jan 2021.

Vancouver:

Filippakis T. ΘΕΩΡΙΑ ΤΟΥ ΦΑΣΙΚΟΥ ΧΩΡΟΥ ΤΗΣ ΜΗ-ΑΡΝΗΤΙΚΗΣ ΣΥΝΑΡΤΗΣΗΣ ΚΑΤΑΝΟΜΗΣ ΤΥΠΟΥ WIGNER. [Internet] [Thesis]. University of Patras; Πανεπιστήμιο Πατρών; 1986. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/10442/hedi/0006.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Filippakis T. ΘΕΩΡΙΑ ΤΟΥ ΦΑΣΙΚΟΥ ΧΩΡΟΥ ΤΗΣ ΜΗ-ΑΡΝΗΤΙΚΗΣ ΣΥΝΑΡΤΗΣΗΣ ΚΑΤΑΝΟΜΗΣ ΤΥΠΟΥ WIGNER. [Thesis]. University of Patras; Πανεπιστήμιο Πατρών; 1986. Available from: http://hdl.handle.net/10442/hedi/0006

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

11. Meier, Dominique. Modélisation d'une interface rugueuse : études numériques et anaytiques : Corrugated interface modeling : numerical and analytical studies.

Degree: Docteur es, Acoustique, 2016, Le Havre

URL: http://www.theses.fr/2016LEHA0027

►

Une modélisation de rugosité de faible amplitude d’une rugosité d’interface, à l’aide de méthodes ultrasonores, est proposée. On examine le cas d’une plaque élastique immergée… (more)

▼

Une modélisation de rugosité de faible amplitude d’une rugosité d’interface, à l’aide de méthodes ultrasonores, est proposée. On examine le cas d’une plaque élastique immergée dont l’une des faces est rugueuse. L’étude de la rugosité dont la géométrie est triangulaire et périodique repose sur l’analyse du coefficient de transmission par la plaque. Une simulation numérique basée sur la Méthode des Éléments Finis est réalisée. D’un autre côté, la théorie de Fiorito, Madigosky et Überall (FMU) de la plaque sans rugosité montre que le coefficient de transmission peut être compris comme une somme de résonances, chacune étant associée à un modèle de Breit et Wigner (BW). La position des pics de résonance, que ceux-ci soient relatifs aux modes symétriques ou antisymétriques sont peu affectées par la présence de la rugosité. Seules les largeurs et les amplitudes varient notablement. Les expériences numériques ont montré que ces pics sont interprétables comme des résonances BW. Une nouvelle modélisation basée sur un modèle rhéologique est établie pour le coefficient de transmission. A partir de celle-ci, un nouveau modèle BW a été développé et validé par la simulation numérique. Celui-ci modèle permet de remplacer avantageusement les simulations numériques coûteuses en temps, par un modèle analytique simple.

The modelling of roughness of small amplitude a rough interface, by using ultrasound methods is proposed. One investigates the case of an immersed elastic plate with only one corrugated face. The study of the roughness, the shape of which is triangular and periodic is based upon the analysis of the transmission coefficient. A numerical simulation using the Finite Element Method (FEM) is carried out. On the other hand, the Fiorito, Madigosky et Überall (FMU) theory of the flat plate shows that the transmission coefficient may be seen as a sum of resonances, each being associated with a Breit-Wigner (BW) resonance shape. The location of the resonance spikes peaks, which are related to either symmetric or antisymmetric modes, are not significantly affected by the roughness ; only the half widths and the magnitudes vary notably. The numerical experiments led with FEM on the corrugated plate showed that the spikes peaks can be interpreted as BW resonances.

Advisors/Committee Members: Franklin, Hervé (thesis director).

Subjects/Keywords: Modèle de Breit-Wigner; Modèle de Jones; Lamb Waves; Acoustic resonance; Roughness; Breit-Wigner model; Jones modem

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Meier, D. (2016). Modélisation d'une interface rugueuse : études numériques et anaytiques : Corrugated interface modeling : numerical and analytical studies. (Doctoral Dissertation). Le Havre. Retrieved from http://www.theses.fr/2016LEHA0027

Chicago Manual of Style (16^th Edition):

Meier, Dominique. “Modélisation d'une interface rugueuse : études numériques et anaytiques : Corrugated interface modeling : numerical and analytical studies.” 2016. Doctoral Dissertation, Le Havre. Accessed January 22, 2021. http://www.theses.fr/2016LEHA0027.

MLA Handbook (7^th Edition):

Meier, Dominique. “Modélisation d'une interface rugueuse : études numériques et anaytiques : Corrugated interface modeling : numerical and analytical studies.” 2016. Web. 22 Jan 2021.

Vancouver:

Meier D. Modélisation d'une interface rugueuse : études numériques et anaytiques : Corrugated interface modeling : numerical and analytical studies. [Internet] [Doctoral dissertation]. Le Havre; 2016. [cited 2021 Jan 22]. Available from: http://www.theses.fr/2016LEHA0027.

Council of Science Editors:

Meier D. Modélisation d'une interface rugueuse : études numériques et anaytiques : Corrugated interface modeling : numerical and analytical studies. [Doctoral Dissertation]. Le Havre; 2016. Available from: http://www.theses.fr/2016LEHA0027

12. Igor Rochaid Oliveira Ramos. Estudo de um sistema clÃssico de dipolos magnÃticos carregados em estruturas de bicamadas.

Degree: Master, 2010, Universidade Federal do Ceará

URL: http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=5443 ;

►

Estudamos as estruturas e as propriedades dinÃmicas de um cristal clÃssico bidimensional (2D) em bicamadas de partÃculas dipolares magnÃticas carregadas em um arranjo no qual… (more)

▼

Estudamos as estruturas e as propriedades dinÃmicas de um cristal clÃssico bidimensional (2D) em bicamadas de partÃculas dipolares magnÃticas carregadas em um arranjo no qual os dipolos sÃo perpendiculares Ãs camadas e com mesma densidade de partÃculas em cada camada. A energia do sistema Ã devido Ã interaÃÃo carga - carga (interaÃÃo coulom- biana) e a interaÃÃo dipolo - dipolo. Devido ao fato dessas interaÃÃes serem de longo alcance, usamos o mÃtodo da soma de Ewald para obter uma expressÃo para a energia envolvendo somas que convergem rapidamente. Comparando as energias de possÃveis geometrias do cristal, determinamos o diagrama de fase do sistema em funÃÃo do parÃmetro η (que estÃ relacionado com a distÃncia entre as camadas de dipolos magnÃticos carregados e a densidade de partÃculas) e da intensidade relativa das interaÃÃes elÃtrica e magnÃtica. Mudando a intensidade relativa da interacÃo dipolo - dipolo com respeito Ã interaÃÃo elÃtrica, podemos encontrar seis diferentes estruturas cristalinas estÃveis em funÃÃo de η. Uma caracterÃstica interessante desse sistema Ã a possibilidade de permanecer em arranjos nos quais as camadas sÃo ou nÃo deslocadas uma em relaÃÃo a outra, apenas variando a interaÃÃo magnÃtica entre os dipolos, por exemplo, atravÃs de um campo magnÃtico externo. As transiÃÃes entre as estruturas cristalinas podem ser contÃnuas e descontÃnuas. No intuito de investigar a estabilidade das configuraÃÃes de mÃnima energia, calculamos o espectro dos fÃnons do sistema usando a aproximaÃÃo harmÃnica. Para isto, recorremos novamente a tÃcnica de Ewald para obter somas que convergem rapidamente. A anÃlise da relaÃÃo de dispersÃo (fÃnons) revela caracterÃsticas do sistema que sÃo de grande utilidade no estudo da transiÃÃo sÃlido-lÃquido (fusÃo).

We study the structural and dynamical properties of a two-dimensional (2D) classical bi-layer crystal of charged magnetic dipolar particles in a setup where the dipoles are oriented perpendicular to the layers and equal density of charged dipolar particles in each layer. The energy of the system is due to the charge - charge interaction (Coulomb interaction) and the dipole - dipole interaction. Due to the long-range nature of the interactions, we use the Ewald summation method to obtain an expression for the energy involving rapidly convergent sums. By comparing the energies of a number of possible crystal geometries, we determine the phase diagram of the system as a function of the parameter η (which is related to the separation between the layers of charged magnetic dipoles and the particle density) and the relative intensity of the magnetic and electrical interactions. By changing the relative intensity of the dipole - dipole interaction with respect to electrical one, we are able to find six diferent stable crystalline structures as a function of η. An interesting feature of the present model system is the possibility to tune between the matched and staggered arrangements by varying the magnetic interaction between the dipoles, e.g.…

Advisors/Committee Members: Wandemberg Paiva Ferreira.

Subjects/Keywords: DINAMICA DA REDE E ESTATISTICA DE CRISTAIS; Wigner Crystal; fÃnons; Soma de Ewald; Cristais de Wigner; phonons; Ewald summation

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Ramos, I. R. O. (2010). Estudo de um sistema clÃssico de dipolos magnÃticos carregados em estruturas de bicamadas. (Masters Thesis). Universidade Federal do Ceará. Retrieved from http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=5443 ;

Chicago Manual of Style (16^th Edition):

Ramos, Igor Rochaid Oliveira. “Estudo de um sistema clÃssico de dipolos magnÃticos carregados em estruturas de bicamadas.” 2010. Masters Thesis, Universidade Federal do Ceará. Accessed January 22, 2021. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=5443 ;.

MLA Handbook (7^th Edition):

Ramos, Igor Rochaid Oliveira. “Estudo de um sistema clÃssico de dipolos magnÃticos carregados em estruturas de bicamadas.” 2010. Web. 22 Jan 2021.

Vancouver:

Ramos IRO. Estudo de um sistema clÃssico de dipolos magnÃticos carregados em estruturas de bicamadas. [Internet] [Masters thesis]. Universidade Federal do Ceará 2010. [cited 2021 Jan 22]. Available from: http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=5443 ;.

Council of Science Editors:

Ramos IRO. Estudo de um sistema clÃssico de dipolos magnÃticos carregados em estruturas de bicamadas. [Masters Thesis]. Universidade Federal do Ceará 2010. Available from: http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=5443 ;

University of Gothenburg / Göteborgs Universitet

13. Svensson, S. Karl-Mikael. Quantum dynamical effects in complex chemical systems.

Degree: 2020, University of Gothenburg / Göteborgs Universitet

URL: http://hdl.handle.net/2077/64131

► When using mathematical models to computationally investigate a chemical system it is important that the methods used are accurate enough to account for the relevant… (more)

Subjects/Keywords: Quantum dynamics; Radiative association; Classical Wigner method; Feynman path integral; Reaction rate constants; Wigner phase space

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Svensson, S. K. (2020). Quantum dynamical effects in complex chemical systems. (Thesis). University of Gothenburg / Göteborgs Universitet. Retrieved from http://hdl.handle.net/2077/64131

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Svensson, S Karl-Mikael. “Quantum dynamical effects in complex chemical systems.” 2020. Thesis, University of Gothenburg / Göteborgs Universitet. Accessed January 22, 2021. http://hdl.handle.net/2077/64131.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Svensson, S Karl-Mikael. “Quantum dynamical effects in complex chemical systems.” 2020. Web. 22 Jan 2021.

Vancouver:

Svensson SK. Quantum dynamical effects in complex chemical systems. [Internet] [Thesis]. University of Gothenburg / Göteborgs Universitet; 2020. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/2077/64131.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Svensson SK. Quantum dynamical effects in complex chemical systems. [Thesis]. University of Gothenburg / Göteborgs Universitet; 2020. Available from: http://hdl.handle.net/2077/64131

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

14. Chabu, Victor. Analyse semiclassique de l'équation de Schrödinger à potentiels singuliers : Semiclassical analysis of the Schrödinger equation with singular potentials.

Degree: Docteur es, Mathématiques, 2016, Université Paris-Est

URL: http://www.theses.fr/2016PESC1029

►

Dans la première partie de cette thèse nous étudions la propagation des mesures de Wigner associées aux solutions de l'équation de Schrödinger à potentiels présentant… (more)

▼

Dans la première partie de cette thèse nous étudions la propagation des mesures de Wigner associées aux solutions de l'équation de Schrödinger à potentiels présentant des singularités coniques, et nous montrons qu'elles sont transportées par deux différents flots Hamiltoniens, l'un sur le fibré cotangent à la variété des singularités et l'autre ailleurs dans l'espace des phases, à moins d'un phénomène d'échange entre ces deux régimes qui peut se produire quand des trajectoires du flot extérieur atteignent le fibré cotangent. Nous décrivons en détail et le flot et la concentration de masse autour et sur la variété singulière, et illustrons avec des exemples quelques questions issues de la faute d'unicité des trajectoires classiques sur les singularités en dépit de l'unicité des solutions quantiques, ce qui refute tout principe de sélection classique, mais qui n'empêche dans certains cas de résoudre complètement le problème.Dans la deuxième partie nous présentons un travail mené en collaboration avec Dr. Clotilde Fermanian et Dr. Fabricio Macià où nous analysons une équation de type Schrödinger pertinente à l'étude semiclassique de la dynamique d'un électron dans un cristal avec impuretés et montrons que, dans la limite où la période caractérisique du réseau cristallin est sufisamment petite par rapport à la variation du potentiel extérieur représentant les impuretés, cette équation peut être approximée par une équation de masse effective, ou, plus généralement, que sa solution se décompose en modes de Bloch et que chacun d'eux satisfait une équation de masse effective spécifique à son énergie de Bloch

In the first part of this thesis we study the propagation of Wigner measures linked to solutions of the Schrödinger equation with potentials presenting conical singularities and show that they are transported by two different Hamiltonian flows, one over the bundle cotangent to the singular set and the other elsewhere in the phase space, up to a transference phenomenon between these two regimes that may arise whenever trajectories in the outsider flow lead in or out the bundle. We describe in detail either the flow and the mass concentration around and on the singular set and illustrate with examples some issues raised by the lack of uniqueness for the classical trajectories on the singularities despite the uniqueness of quantum solutions, dismissing any classical selection principle, but in some cases being able to fully solve the problem.In the second part we present a work in collaboration with Dr. Clotilde Fermanian and Dr. Fabricio Macià where we analyse a Schrödinger-like equation pertinent to the semiclassical study of the dynamics of an electron in a crystal with impurities, showing that in the limit where the characteristic lenght of the crystal's lattice can be considered sufficiently small with respect to the variation of the exterior potential modelling the impurities, then this equation is approximated by an effective mass equation, or, more generally, that its solution decomposes in terms of Bloch modes,…

Advisors/Committee Members: Fermanian-Kammerer, Clotilde (thesis director).

Subjects/Keywords: Analyse semi-Classique; Mesures de Wigner; Équation de Schrödinger; Décomposition de Bloch; Semiclassical analysis; Wigner measures; Schrödinger's equation; Bloch decompostiion

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Chabu, V. (2016). Analyse semiclassique de l'équation de Schrödinger à potentiels singuliers : Semiclassical analysis of the Schrödinger equation with singular potentials. (Doctoral Dissertation). Université Paris-Est. Retrieved from http://www.theses.fr/2016PESC1029

Chicago Manual of Style (16^th Edition):

Chabu, Victor. “Analyse semiclassique de l'équation de Schrödinger à potentiels singuliers : Semiclassical analysis of the Schrödinger equation with singular potentials.” 2016. Doctoral Dissertation, Université Paris-Est. Accessed January 22, 2021. http://www.theses.fr/2016PESC1029.

MLA Handbook (7^th Edition):

Chabu, Victor. “Analyse semiclassique de l'équation de Schrödinger à potentiels singuliers : Semiclassical analysis of the Schrödinger equation with singular potentials.” 2016. Web. 22 Jan 2021.

Vancouver:

Chabu V. Analyse semiclassique de l'équation de Schrödinger à potentiels singuliers : Semiclassical analysis of the Schrödinger equation with singular potentials. [Internet] [Doctoral dissertation]. Université Paris-Est; 2016. [cited 2021 Jan 22]. Available from: http://www.theses.fr/2016PESC1029.

Council of Science Editors:

Chabu V. Analyse semiclassique de l'équation de Schrödinger à potentiels singuliers : Semiclassical analysis of the Schrödinger equation with singular potentials. [Doctoral Dissertation]. Université Paris-Est; 2016. Available from: http://www.theses.fr/2016PESC1029

Université de Bordeaux I

15. Arbelo Gonzalez, Wilmer. Nouvelles perspectives dans les traitements classique et semiclassique de la dynamique réactionnelle : New insights into the classical and semiclassical treatments of chemical reaction dynamics.

Degree: Docteur es, Chimie-Physique, 2013, Université de Bordeaux I

URL: http://www.theses.fr/2013BOR14668

►

La théorie de la dynamique des processus chimiques élementaires cherche à décrire quantitativement les collisions réactives à l'échelle atomique. Les mouvements des noyaux étant extrêmement… (more)

Subjects/Keywords: Dynamique réactionnelle; Approche semi-classique; Photodissociation; Distribution de Wigner; Chemical reaction dynamics; Semi-classical approach; Photodissociation; Wigner distribution function

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Arbelo Gonzalez, W. (2013). Nouvelles perspectives dans les traitements classique et semiclassique de la dynamique réactionnelle : New insights into the classical and semiclassical treatments of chemical reaction dynamics. (Doctoral Dissertation). Université de Bordeaux I. Retrieved from http://www.theses.fr/2013BOR14668

Chicago Manual of Style (16^th Edition):

Arbelo Gonzalez, Wilmer. “Nouvelles perspectives dans les traitements classique et semiclassique de la dynamique réactionnelle : New insights into the classical and semiclassical treatments of chemical reaction dynamics.” 2013. Doctoral Dissertation, Université de Bordeaux I. Accessed January 22, 2021. http://www.theses.fr/2013BOR14668.

MLA Handbook (7^th Edition):

Arbelo Gonzalez, Wilmer. “Nouvelles perspectives dans les traitements classique et semiclassique de la dynamique réactionnelle : New insights into the classical and semiclassical treatments of chemical reaction dynamics.” 2013. Web. 22 Jan 2021.

Vancouver:

Arbelo Gonzalez W. Nouvelles perspectives dans les traitements classique et semiclassique de la dynamique réactionnelle : New insights into the classical and semiclassical treatments of chemical reaction dynamics. [Internet] [Doctoral dissertation]. Université de Bordeaux I; 2013. [cited 2021 Jan 22]. Available from: http://www.theses.fr/2013BOR14668.

Council of Science Editors:

Arbelo Gonzalez W. Nouvelles perspectives dans les traitements classique et semiclassique de la dynamique réactionnelle : New insights into the classical and semiclassical treatments of chemical reaction dynamics. [Doctoral Dissertation]. Université de Bordeaux I; 2013. Available from: http://www.theses.fr/2013BOR14668

NSYSU

16. Liao, Wen-hao. Constructing a Wigner-like distribution function of phase space with Mexican hat wavelet.

Degree: Master, Physics, 2008, NSYSU

URL: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0122108-162358

none Advisors/Committee Members: I-Min Jiang (chair), De-Hone Lin (chair), Wang-Chuang Kuo (committee member).

Subjects/Keywords: mexican hat wavelet; wigner function

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Liao, W. (2008). Constructing a Wigner-like distribution function of phase space with Mexican hat wavelet. (Thesis). NSYSU. Retrieved from http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0122108-162358

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Liao, Wen-hao. “Constructing a Wigner-like distribution function of phase space with Mexican hat wavelet.” 2008. Thesis, NSYSU. Accessed January 22, 2021. http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0122108-162358.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Liao, Wen-hao. “Constructing a Wigner-like distribution function of phase space with Mexican hat wavelet.” 2008. Web. 22 Jan 2021.

Vancouver:

Liao W. Constructing a Wigner-like distribution function of phase space with Mexican hat wavelet. [Internet] [Thesis]. NSYSU; 2008. [cited 2021 Jan 22]. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0122108-162358.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Liao W. Constructing a Wigner-like distribution function of phase space with Mexican hat wavelet. [Thesis]. NSYSU; 2008. Available from: http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0122108-162358

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Manchester

17. Lasithiotakis, Michail Georgioy. Irradiated Graphite Waste - Stored Energy.

Degree: 2012, University of Manchester

URL: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:157175

► The cores of early UK graphite moderated research and production nuclear fission reactors operated at temperatures below 150°C. Due to this low temperature their core… (more)

▼ The cores of early UK graphite moderated research and production nuclear fission reactors operated at temperatures below 150°C. Due to this low temperature their core graphite contains significant amounts of stored (Wigner) energy that may be released by heating the graphite above the irradiation temperature. This exothermic behavior has lead to a number of decommissioning issues which are related to long term "safe-storage", reactor core dismantling, graphite waste packaging and the final disposal of this irradiated graphite waste. The release of stored energy can be modeled using kinetic models. These models rely on empirical data obtained either from graphite samples irradiated in Material Test Reactors (MTR) or data obtained from small samples obtained from the reactors themselves. Data from these experiments is used to derive activation energies and characteristic functions used in kinetic models. This present research involved the development of an understanding of the different grades of graphite, relating the accumulation of stored energy to reactor irradiation history and an investigation of historic stored energy data. The release of stored energy under various conditions applicable to decommissioning has been conducted using thermal analysis techniques such as Differential Scanning Calorimetry (DSC). Kinetic models were developed, validated and applied, suitable for the study of stored energy release in irradiated graphite components. A potentially valid method was developed, for determining the stored energy content of graphite components and the kinetics of energy release.Another parameter investigated in this study was dedicated in the simulation of irradiation damage using ion irradiation. Ion bombardment of small graphite samples is a convenient method of simulating fast neutron irradiation damage. In order to gain confidence that irradiation damage due to ion irradiation is a good model for neutron irradiation damage the properties and microstructure of various grades of ion irradiated nuclear graphite were also investigated. Raman Spectroscopy was employed to compare the effects of ion bombardment with the reported effects of neutron irradiation on the content of the defects. The changes of the of defect content with thermal annealing of the ion irradiated graphite have been compared with the annealing of neutron irradiated nuclear graphite Advisors/Committee Members: MARROW, THOMAS TJ, Marrow, Thomas, Marsden, Barry.

Subjects/Keywords: Graphite, Wigner energy, activation energy, kinetics, defects; Annealing

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lasithiotakis, M. G. (2012). Irradiated Graphite Waste - Stored Energy. (Doctoral Dissertation). University of Manchester. Retrieved from http://www.manchester.ac.uk/escholar/uk-ac-man-scw:157175

Chicago Manual of Style (16^th Edition):

Lasithiotakis, Michail Georgioy. “Irradiated Graphite Waste - Stored Energy.” 2012. Doctoral Dissertation, University of Manchester. Accessed January 22, 2021. http://www.manchester.ac.uk/escholar/uk-ac-man-scw:157175.

MLA Handbook (7^th Edition):

Lasithiotakis, Michail Georgioy. “Irradiated Graphite Waste - Stored Energy.” 2012. Web. 22 Jan 2021.

Vancouver:

Lasithiotakis MG. Irradiated Graphite Waste - Stored Energy. [Internet] [Doctoral dissertation]. University of Manchester; 2012. [cited 2021 Jan 22]. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:157175.

Council of Science Editors:

Lasithiotakis MG. Irradiated Graphite Waste - Stored Energy. [Doctoral Dissertation]. University of Manchester; 2012. Available from: http://www.manchester.ac.uk/escholar/uk-ac-man-scw:157175

Universidade de Brasília

18. Ronni Geraldo Gomes de Amorim. Formulação de teorias de campos via estruturas simpléticas e o produto de Weyl.

Degree: 2006, Universidade de Brasília

URL: http://bdtd.bce.unb.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=217

►

Neste trabalho, utiliza-se operadores-estrela definidos a partir do produto de Weyl em geometria não comutativa, para estudar representações unitárias para os grupos de Galilei e… (more)

Subjects/Keywords: função Wigner; grupos de Lie; produto-estrela; FISICA

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APA (6^th Edition):

Amorim, R. G. G. d. (2006). Formulação de teorias de campos via estruturas simpléticas e o produto de Weyl. (Thesis). Universidade de Brasília. Retrieved from http://bdtd.bce.unb.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=217

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Amorim, Ronni Geraldo Gomes de. “Formulação de teorias de campos via estruturas simpléticas e o produto de Weyl.” 2006. Thesis, Universidade de Brasília. Accessed January 22, 2021. http://bdtd.bce.unb.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=217.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Amorim, Ronni Geraldo Gomes de. “Formulação de teorias de campos via estruturas simpléticas e o produto de Weyl.” 2006. Web. 22 Jan 2021.

Vancouver:

Amorim RGGd. Formulação de teorias de campos via estruturas simpléticas e o produto de Weyl. [Internet] [Thesis]. Universidade de Brasília; 2006. [cited 2021 Jan 22]. Available from: http://bdtd.bce.unb.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=217.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Amorim RGGd. Formulação de teorias de campos via estruturas simpléticas e o produto de Weyl. [Thesis]. Universidade de Brasília; 2006. Available from: http://bdtd.bce.unb.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=217

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Colorado

19. Su, Jing. Theoretical Analysis and Numerical Simulation of Attosecond Time Delays in Photoionization.

Degree: PhD, Physics, 2014, University of Colorado

URL: https://scholar.colorado.edu/phys_gradetds/111

► Recent developments in laser technology, in particular the advances in high-harmonic generation, enable the generation of ultrashort extreme ultraviolet (XUV) pulses with attosecond (1… (more)

▼ Recent developments in laser technology, in particular the advances in high-harmonic generation, enable the generation of ultrashort extreme ultraviolet (XUV) pulses with attosecond (1 as = 10⁻¹⁸ s) duration. Such tools open the opportunity to study electron dynamics in atoms and molecules on its intrinsic time scale. As an example, the attosecond streaking technique was recently applied to time resolve the photoionization process in atomic and solid systems. In this technique, an isolated attosecond XUV pulse, that ionizes the electron in the target system, is superimposed with a few-cycle streaking pulse (usually of near-infrared wavelengths). The streaking pulse modulates the final momentum (or energy) of the photoelectron. The measured streaking trace, i.e., the final momentum (or energy) as a function of the relative delay between these two pulses, contains time information of the photoionization process. By comparing two streaking traces measured for photoionization from the 2s and 2p orbitals in a neon atom, Schultze et al. [Science 328, 1658 (2010)] found a temporal offset of 21 ± 5 as between them and interpreted this value as the time delay between photoionization from the 2s and 2p orbitals. This experiment has initiated a debate among theoreticians, in particular about the origin of the measured time delay. A correct interpretation of the delay is extremely important for our understanding of the attosecond streaking technique and an exact analysis of time resolved measurements of this and other ultrafast processes. In this thesis we systematically study the attosecond time delays in photoionization using numerical simulations. We first propose a new method, based on the fundamental definition of a time delay, to theoretically study the photoionization process induced by an XUV pulse from a time-dependent perspective. We then turn to analyze the time delays measured in streaking experiments. Our results show that for single-photon ionization the observed streaking time delay arises from the finite-range propagation of the photoelectron in the coupled field of the ionic potential and the streaking pulse. Consequently, we conclude that the photon absorption occurs instantaneously at the center of the XUV pulse, i.e., with no time delay. Our analysis further reveals that the streaking time delay can be interpreted as a finite sum of piecewise field-free time delays weighted by the relative instantaneous streaking field strength and provides itself as a useful tool for imaging the presence of an additional potential located at a distance from the ionic core. We finally extend our time delay studies to the two-photon ionization process and show that the absorption time delay is significantly different for nonresonant and resonant two-photon ionization. Our results imply that the absorption of two photons in the nonresonant case occurs instantaneously, without time delay, at the center of the XUV pulse. However, in the resonant scenario we find a substantial absorption time… Advisors/Committee Members: Andreas Becker, Agnieszka Jaron-Becker, Henry Kapteyn, Steven Cundiff, David Jonas.

Subjects/Keywords: streaking; propagation; absorption; Schrödinger; Wigner-Smith; Atomic, Molecular and Optical Physics

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Su, J. (2014). Theoretical Analysis and Numerical Simulation of Attosecond Time Delays in Photoionization. (Doctoral Dissertation). University of Colorado. Retrieved from https://scholar.colorado.edu/phys_gradetds/111

Chicago Manual of Style (16^th Edition):

Su, Jing. “Theoretical Analysis and Numerical Simulation of Attosecond Time Delays in Photoionization.” 2014. Doctoral Dissertation, University of Colorado. Accessed January 22, 2021. https://scholar.colorado.edu/phys_gradetds/111.

MLA Handbook (7^th Edition):

Su, Jing. “Theoretical Analysis and Numerical Simulation of Attosecond Time Delays in Photoionization.” 2014. Web. 22 Jan 2021.

Vancouver:

Su J. Theoretical Analysis and Numerical Simulation of Attosecond Time Delays in Photoionization. [Internet] [Doctoral dissertation]. University of Colorado; 2014. [cited 2021 Jan 22]. Available from: https://scholar.colorado.edu/phys_gradetds/111.

Council of Science Editors:

Su J. Theoretical Analysis and Numerical Simulation of Attosecond Time Delays in Photoionization. [Doctoral Dissertation]. University of Colorado; 2014. Available from: https://scholar.colorado.edu/phys_gradetds/111

University of Manchester

20. Lasithiotakis, Michail Georgioy. Irradiated graphite waste - stored energy.

Degree: PhD, 2012, University of Manchester

URL: https://www.research.manchester.ac.uk/portal/en/theses/irradiated-graphite-waste – stored-energy(c93c7581-5273-4d30-a05b-2153b4c7cfaf).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553492

► The cores of early UK graphite moderated research and production nuclear fission reactors operated at temperatures below 150°C. Due to this low temperature their core… (more)

▼ The cores of early UK graphite moderated research and production nuclear fission reactors operated at temperatures below 150°C. Due to this low temperature their core graphite contains significant amounts of stored (Wigner) energy that may be released by heating the graphite above the irradiation temperature. This exothermic behavior has lead to a number of decommissioning issues which are related to long term "safe-storage", reactor core dismantling, graphite waste packaging and the final disposal of this irradiated graphite waste. The release of stored energy can be modeled using kinetic models. These models rely on empirical data obtained either from graphite samples irradiated in Material Test Reactors (MTR) or data obtained from small samples obtained from the reactors themselves. Data from these experiments is used to derive activation energies and characteristic functions used in kinetic models. This present research involved the development of an understanding of the different grades of graphite, relating the accumulation of stored energy to reactor irradiation history and an investigation of historic stored energy data. The release of stored energy under various conditions applicable to decommissioning has been conducted using thermal analysis techniques such as Differential Scanning Calorimetry (DSC). Kinetic models were developed, validated and applied, suitable for the study of stored energy release in irradiated graphite components. A potentially valid method was developed, for determining the stored energy content of graphite components and the kinetics of energy release. Another parameter investigated in this study was dedicated in the simulation of irradiation damage using ion irradiation. Ion bombardment of small graphite samples is a convenient method of simulating fast neutron irradiation damage. In order to gain confidence that irradiation damage due to ion irradiation is a good model for neutron irradiation damage the properties and microstructure of various grades of ion irradiated nuclear graphite were also investigated. Raman Spectroscopy was employed to compare the effects of ion bombardment with the reported effects of neutron irradiation on the content of the defects. The changes of the of defect content with thermal annealing of the ion irradiated graphite have been compared with the annealing of neutron irradiated nuclear graphite.

Subjects/Keywords: 621.4838; Graphite; Wigner energy; activation energy; kinetics; defects; Annealing

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Lasithiotakis, M. G. (2012). Irradiated graphite waste - stored energy. (Doctoral Dissertation). University of Manchester. Retrieved from https://www.research.manchester.ac.uk/portal/en/theses/irradiated-graphite-waste – stored-energy(c93c7581-5273-4d30-a05b-2153b4c7cfaf).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553492

Chicago Manual of Style (16^th Edition):

Lasithiotakis, Michail Georgioy. “Irradiated graphite waste - stored energy.” 2012. Doctoral Dissertation, University of Manchester. Accessed January 22, 2021. https://www.research.manchester.ac.uk/portal/en/theses/irradiated-graphite-waste – stored-energy(c93c7581-5273-4d30-a05b-2153b4c7cfaf).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553492.

MLA Handbook (7^th Edition):

Lasithiotakis, Michail Georgioy. “Irradiated graphite waste - stored energy.” 2012. Web. 22 Jan 2021.

Vancouver:

Lasithiotakis MG. Irradiated graphite waste - stored energy. [Internet] [Doctoral dissertation]. University of Manchester; 2012. [cited 2021 Jan 22]. Available from: https://www.research.manchester.ac.uk/portal/en/theses/irradiated-graphite-waste – stored-energy(c93c7581-5273-4d30-a05b-2153b4c7cfaf).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553492.

Council of Science Editors:

Lasithiotakis MG. Irradiated graphite waste - stored energy. [Doctoral Dissertation]. University of Manchester; 2012. Available from: https://www.research.manchester.ac.uk/portal/en/theses/irradiated-graphite-waste – stored-energy(c93c7581-5273-4d30-a05b-2153b4c7cfaf).html ; http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.553492

Princeton University

21. Deng, Hao. Interacting Bilayer Electron System .

Degree: PhD, 2018, Princeton University

URL: http://arks.princeton.edu/ark:/88435/dsp01jd473023r

► This thesis summarizes the explorations of interacting bilayer electron systems which provide a versatile, extended platform to study electron-electron interaction beyond single layers. By setting… (more)

▼ This thesis summarizes the explorations of interacting bilayer electron systems which provide a versatile, extended platform to study electron-electron interaction beyond single layers. By setting each layer at a different density, the bilayer electron system hosts different electronic phases in each layer; moreover, we can study the role of interaction between these phases when the two layers are closely spaced. We first present a new technique and experimental results directly probing the magnetic-field-induced Wigner crystal (WC) through its interaction with another many-body phase which is comprised of composite fermions (CFs). We measure the magnetoresistance of a bilayer electron system where one layer has a very low density and is in the WC regime, while the other (probe) layer is near half Landau level filling and hosts a sea of CFs. The data exhibit commensurability oscillations in the magnetoresistance of the CF layer, induced by the periodic potential of WC electrons in the other layer, and provide a unique, direct glimpse at the symmetry of the WC, its lattice constant, and melting. They also demonstrate a striking example of how one can probe the many-body state of two-dimensional electrons using another many-body state with exotic quasiparticles. We also report experiments demonstrating that the layer densities of an asymmetric bilayer electron system oscillate as a function of perpendicular magnetic field that quantizes the energy levels. At intermediate fields, this interlayer charge transfer can be well explained by the alignment of the Landau levels in the two layers. At the highest fields where both layers reach the extreme quantum limit, however, there is an anomalous, enhanced charge transfer to the majority layer. Surprisingly, when the minority layer becomes extremely dilute, this charge transfer slows down as the electrons in the minority layer condense into a WC. Furthermore, by examining the quantum capacitance of the dilute layer at high fields, the screening induced by the CFs in an adjacent layer is unveiled. The results highlight the influence of strong interaction in interlayer charge transfer in the regime of very high fields and low Landau level filling factors. By further scrutinizing the details of the interlayer charge transfer as a function of magnetic field and its termination as mentioned above, we are able to measure the critical filling factor (CFF) below which a magnetic-field-induced, quantum WC forms in a dilute, two-dimensional electron layer when a second, high-density electron layer is present in close proximity. The data reveal that the WC forms at a significantly smaller CFF compared to the CFF (≃ 0.20) in single-layer two-dimensional electron systems. The measured CFF exhibits a strong dependence on the interlayer distance, reflecting the interaction and screening from the adjacent, high-density layer. Advisors/Committee Members: Shayegan, Mansour (advisor).

Subjects/Keywords: 2DES; Bilayer; composite fermion; interlayer interaction; Wigner crystal

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Deng, H. (2018). Interacting Bilayer Electron System . (Doctoral Dissertation). Princeton University. Retrieved from http://arks.princeton.edu/ark:/88435/dsp01jd473023r

Chicago Manual of Style (16^th Edition):

Deng, Hao. “Interacting Bilayer Electron System .” 2018. Doctoral Dissertation, Princeton University. Accessed January 22, 2021. http://arks.princeton.edu/ark:/88435/dsp01jd473023r.

MLA Handbook (7^th Edition):

Deng, Hao. “Interacting Bilayer Electron System .” 2018. Web. 22 Jan 2021.

Vancouver:

Deng H. Interacting Bilayer Electron System . [Internet] [Doctoral dissertation]. Princeton University; 2018. [cited 2021 Jan 22]. Available from: http://arks.princeton.edu/ark:/88435/dsp01jd473023r.

Council of Science Editors:

Deng H. Interacting Bilayer Electron System . [Doctoral Dissertation]. Princeton University; 2018. Available from: http://arks.princeton.edu/ark:/88435/dsp01jd473023r

Princeton University

22. Liu, Yang. Magneto-Transport Study of Quantum Phases in Wide GaAs Quantum Wells .

Degree: PhD, 2014, Princeton University

URL: http://arks.princeton.edu/ark:/88435/dsp0105741r842

► In this thesis we study several quantum phases in very high quality two-dimensional electron systems (2DESs) confined to GaAs single wide quantum wells (QWs). In… (more)

▼ In this thesis we study several quantum phases in very high quality two-dimensional electron systems (2DESs) confined to GaAs single wide quantum wells (QWs). In these systems typically two electric subbands are occupied. By controlling the electron density as well as the QW symmetry, we can fine tune the cyclotron and subband separation energies, so that Landau levels (LLs) belonging to different subbands cross at the Fermi energy EF. The additional subband degree of freedom enables us to study different quantum phases. Magneto-transport measurements at fixed electron density n and various QW symmetries reveal a remarkable pattern for the appearance and disappearance of fractional quantum Hall (FQH) states at LL filling factors &nu = 10/3, 11/3, 13/3, 14/3, 16/3, and 17/3. These q/3 states are stable and strong as long as EF lies in a ground-state (N=0) LL, regardless of whether that level belongs to the symmetric or the anti-symmetric subband. We also observe subtle and distinct evolutions near filling factors &nu = 5/2 and 7/2, as we change the density n, or the symmetry of the charge distribution. The even-denominator FQH states are observed at &nu = 5/2, 7/2, 9/2 and 11/2 when EF lies in the N=1 LLs of the symmetric subband (the S1 levels). As we increase n, the &nu=5/2 FQH state suddenly disappears and turns into a compressible state once EF moves to the spin-up, N=0, anti-symmetric LL (the A0 level). The sharpness of this disappearance suggests a first-order transition from a FQH to a compressible state. Moreover, thanks to the renormalization of the susbband energy separation in a well with asymmetric change distribution, two LLs can get pinned to each other when they are crossing at EF. We observe a remarkable consequence of such pinning: There is a developing FQH state when the LL filling factor of the symmetric subband &nuS equals 5/2 while the antisymmetric subband has filling 1<&nuA<2. Next, we study the evolution of the &nu=5/2 and 7/2 FQH states as we add a parallel magnetic field, B||, in the plane of the sample. The first-order transitions at &nu=5/2 and 7/2 are softened when B|| is applied, thanks to the mixing of the LLs from different subbands. Meanwhile, a small B|| also introduces a severe transport anisotropy at &nu=5/2 while the FQH state still remains reasonably strong. Several other novel phenomena are also observed in wide QWs. In high (N &ge 2) LLs, our study reveals an unexpected rotation of the orientation of the stripe phase observed at a half-filled LL. This rotation is sensitive to the spin of the LL and the symmetry of the charge distribution in the QW. In the lowest LL, we observe a close competition between electron liquid and solid phases near filling factor &nu=1. In perticular, we observe a reentrant &nu=1… Advisors/Committee Members: Shayegan, Mansour (advisor).

Subjects/Keywords: 2DES; Fractional quantum Hall effect; Magneto-transport; Wigner crystal

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Liu, Y. (2014). Magneto-Transport Study of Quantum Phases in Wide GaAs Quantum Wells . (Doctoral Dissertation). Princeton University. Retrieved from http://arks.princeton.edu/ark:/88435/dsp0105741r842

Chicago Manual of Style (16^th Edition):

Liu, Yang. “Magneto-Transport Study of Quantum Phases in Wide GaAs Quantum Wells .” 2014. Doctoral Dissertation, Princeton University. Accessed January 22, 2021. http://arks.princeton.edu/ark:/88435/dsp0105741r842.

MLA Handbook (7^th Edition):

Liu, Yang. “Magneto-Transport Study of Quantum Phases in Wide GaAs Quantum Wells .” 2014. Web. 22 Jan 2021.

Vancouver:

Liu Y. Magneto-Transport Study of Quantum Phases in Wide GaAs Quantum Wells . [Internet] [Doctoral dissertation]. Princeton University; 2014. [cited 2021 Jan 22]. Available from: http://arks.princeton.edu/ark:/88435/dsp0105741r842.

Council of Science Editors:

Liu Y. Magneto-Transport Study of Quantum Phases in Wide GaAs Quantum Wells . [Doctoral Dissertation]. Princeton University; 2014. Available from: http://arks.princeton.edu/ark:/88435/dsp0105741r842

23. Regniers, Gilles. Wigner quantization and Lie superalgebra representations.

Degree: 2011, Ghent University

URL: http://hdl.handle.net/1854/LU-1970765

► In quantum mechanics, physical observables are represented by operators on a certain Hilbert space. The question of how such operators commute, has been a matter… (more)

▼ In quantum mechanics, physical observables are represented by operators on a certain Hilbert space. The question of how such operators commute, has been a matter of discussion. In the standard perspective, the operators corresponding to the position and momentum of a system are assumed to satisfy the canonical commutation relations. It is known that these relations imply that the Hamilton and Heisenberg equations of motion are compatible as operator equations. However, Wigner showed that the inverse statement is not true. Therefore, it is a much weaker constraint to impose the compatibility of the equations of motion. For any physical system, this results in a set of compatibility conditions, which form the core of Wigner quantization. The key to finding operators that are subject to the compatibility conditions is provided by Lie superalgebras and their representations. Lie superalgebras can be defined as algebras generated by odd elements satisfying particular superbracket relations. Using these defining relations, Lie superalgebra generators can be found that obey the compatibility conditions. The Lie superalgebra elements act as operators on a vector space if we consider Lie superalgebra representations. Various physical systems are investigated in this thesis in the context of Wigner quantization. For each of these systems solutions are found in terms of Lie superalgebra generators, after which specific representations are examined. In such representations, the focus lies on determining particular physical properties of the system. Most of the studied systems are harmonic oscillator models. First, we examine a set-up of coupled harmonic oscillators, for which the interaction is represented by an interaction matrix. Then we focus on the angular momentum content of a 3N-dimensional harmonic oscillator. Finally, our attention goes to two one-dimensional systems, namely the free particle and the Berry-Keating-Connes Hamiltonian. The latter of these Hamiltonians is notorious for its possible connection with the Riemann hypothesis. All of the aforementioned Hamiltonians have been extensively investigated in the context of canonical quantization, so that our results can be compared to the well-known canonical case. Advisors/Committee Members: Van der Jeugt, Joris.

Subjects/Keywords: Mathematics and Statistics; Wigner quantization; Lie superalgebras; representations

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Regniers, G. (2011). Wigner quantization and Lie superalgebra representations. (Thesis). Ghent University. Retrieved from http://hdl.handle.net/1854/LU-1970765

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Regniers, Gilles. “Wigner quantization and Lie superalgebra representations.” 2011. Thesis, Ghent University. Accessed January 22, 2021. http://hdl.handle.net/1854/LU-1970765.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Regniers, Gilles. “Wigner quantization and Lie superalgebra representations.” 2011. Web. 22 Jan 2021.

Vancouver:

Regniers G. Wigner quantization and Lie superalgebra representations. [Internet] [Thesis]. Ghent University; 2011. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/1854/LU-1970765.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Regniers G. Wigner quantization and Lie superalgebra representations. [Thesis]. Ghent University; 2011. Available from: http://hdl.handle.net/1854/LU-1970765

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Loughborough University

24. Rundle, Russell. Quantum state visualization, verification and validation via phase space methods.

Degree: PhD, 2020, Loughborough University

URL: https://doi.org/10.26174/thesis.lboro.11962620.v1 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.808068

► Since its introduction in the 1930s by Wigner, and its generalisations by Moyal and Weyl, the ability to associate an operator on Hilbert space by… (more)

Subjects/Keywords: Quantum; Quantum Information; Quantum Optics; Phase Space; Wigner Function

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Rundle, R. (2020). Quantum state visualization, verification and validation via phase space methods. (Doctoral Dissertation). Loughborough University. Retrieved from https://doi.org/10.26174/thesis.lboro.11962620.v1 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.808068

Chicago Manual of Style (16^th Edition):

Rundle, Russell. “Quantum state visualization, verification and validation via phase space methods.” 2020. Doctoral Dissertation, Loughborough University. Accessed January 22, 2021. https://doi.org/10.26174/thesis.lboro.11962620.v1 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.808068.

MLA Handbook (7^th Edition):

Rundle, Russell. “Quantum state visualization, verification and validation via phase space methods.” 2020. Web. 22 Jan 2021.

Vancouver:

Rundle R. Quantum state visualization, verification and validation via phase space methods. [Internet] [Doctoral dissertation]. Loughborough University; 2020. [cited 2021 Jan 22]. Available from: https://doi.org/10.26174/thesis.lboro.11962620.v1 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.808068.

Council of Science Editors:

Rundle R. Quantum state visualization, verification and validation via phase space methods. [Doctoral Dissertation]. Loughborough University; 2020. Available from: https://doi.org/10.26174/thesis.lboro.11962620.v1 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.808068

University of British Columbia

25. Garudadri, Harinath. Identification of invariant acoustic cues in stop consonants using the Wigner distribution.

Degree: PhD, Electrical and Computer Engineering, 1987, University of British Columbia

URL: http://hdl.handle.net/2429/28786

► It is a common belief that there are invariant acoustic patterns in speech signals, which can be related to their phonetic description. These patterns are… (more)

▼ It is a common belief that there are invariant acoustic patterns in speech signals, which can be related to their phonetic description. These patterns are expected to remain invariant, independent of the language, speaker, phonetic context, etc. Although many investigations based on short-time spectral analysis have established the feasibility of extracting invariant cues in certain contexts, they could not provide a set of invariant cues in any given phonetic context. In this thesis, the Wigner distribution (WD) was used to analyze speech signals for the first time, to investigate acoustic invariance. The WD, like the spectrogram, provides a time-frequency description of the signal. Unlike the spectrogram, it provides correct marginals in the time and frequency domains, but it is not a positive distribution. It is demonstrated here that the partially smoothed WD, in which both the properties of positivity and correct marginals are sacrificed to some extent, provides a better time-frequency resolution than short-time spectral analyses methods. An implementation and an interpretation of the partially smoothed WD are presented. The choice of smoothing parameters and the nature of cross-term suppression in a partially smoothed WD are discussed in detail. It is shown that the cross-terms in a partially smoothed WD do not mask the underlying nature of a signal in the time-frequency plane. A partially smoothed WD was used to investigate acoustic invariance in voiceless, unaspirated stop consonants spoken by native speakers of English, Telugu and French. Contrary to reports in the literature, it was shown that the features "diffuse-rising" and "compact" spectral shapes were not unique to alveolar and velar places of articulation, respectively, but depended on the vowel context. The resulting ambiguities when specifying the place of articulation were resolved using Formant Onset Duration (time taken for the steady state formants to occur in the vocal tract after the consonantal release) and F₂ of the following vowel. The place of articulation was specified correctly for 86% of the tokens. Unlike in other investigations, the errors in specifying the place of articulation were uniformly distributed over all vowel contexts.

Subjects/Keywords: Speech; Consonants; Wigner distribution

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APA (6^th Edition):

Garudadri, H. (1987). Identification of invariant acoustic cues in stop consonants using the Wigner distribution. (Doctoral Dissertation). University of British Columbia. Retrieved from http://hdl.handle.net/2429/28786

Chicago Manual of Style (16^th Edition):

Garudadri, Harinath. “Identification of invariant acoustic cues in stop consonants using the Wigner distribution.” 1987. Doctoral Dissertation, University of British Columbia. Accessed January 22, 2021. http://hdl.handle.net/2429/28786.

MLA Handbook (7^th Edition):

Garudadri, Harinath. “Identification of invariant acoustic cues in stop consonants using the Wigner distribution.” 1987. Web. 22 Jan 2021.

Vancouver:

Garudadri H. Identification of invariant acoustic cues in stop consonants using the Wigner distribution. [Internet] [Doctoral dissertation]. University of British Columbia; 1987. [cited 2021 Jan 22]. Available from: http://hdl.handle.net/2429/28786.

Council of Science Editors:

Garudadri H. Identification of invariant acoustic cues in stop consonants using the Wigner distribution. [Doctoral Dissertation]. University of British Columbia; 1987. Available from: http://hdl.handle.net/2429/28786

26. Silva, Joao Medeiros e. Cristal de Wigner Blindado.

Degree: PhD, Física Básica, 1980, University of São Paulo

URL: http://www.teses.usp.br/teses/disponiveis/54/54131/tde-19082014-105000/ ;

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No presente trabalho propomos e estudamos um modelo teórico que denominamos Cristal de Wigner Blindado. Assumindo para este sistema uma estrutura ordenada, nos foi possível… (more)

Subjects/Keywords: Cristal de Wigner; Dinâmica de rede; Lattice Dynamics; Wigner Lattice

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APA (6^th Edition):

Silva, J. M. e. (1980). Cristal de Wigner Blindado. (Doctoral Dissertation). University of São Paulo. Retrieved from http://www.teses.usp.br/teses/disponiveis/54/54131/tde-19082014-105000/ ;

Chicago Manual of Style (16^th Edition):

Silva, Joao Medeiros e. “Cristal de Wigner Blindado.” 1980. Doctoral Dissertation, University of São Paulo. Accessed January 22, 2021. http://www.teses.usp.br/teses/disponiveis/54/54131/tde-19082014-105000/ ;.

MLA Handbook (7^th Edition):

Silva, Joao Medeiros e. “Cristal de Wigner Blindado.” 1980. Web. 22 Jan 2021.

Vancouver:

Silva JMe. Cristal de Wigner Blindado. [Internet] [Doctoral dissertation]. University of São Paulo; 1980. [cited 2021 Jan 22]. Available from: http://www.teses.usp.br/teses/disponiveis/54/54131/tde-19082014-105000/ ;.

Council of Science Editors:

Silva JMe. Cristal de Wigner Blindado. [Doctoral Dissertation]. University of São Paulo; 1980. Available from: http://www.teses.usp.br/teses/disponiveis/54/54131/tde-19082014-105000/ ;

27. Filliau, Christophe. Estimation du contrôle nerveux autonome et de l'activité intrinsèque du système cardiaque au moyen de l'analyse de la variabilité des paramètres cardiovasculaires : effets de l'âge et de l’activité physique : Estimation of cardiovascular autonomic conntrol and the intrinsic heart rate from cardiovascular time frequency analysis : Effect of aging ans physical activity.

Degree: Docteur es, Sciences du sport et du mouvement humain, 2015, Université Paris-Saclay (ComUE)

URL: http://www.theses.fr/2015SACLS193

►

Cette étude s’inscrit dans les travaux de recherche visant à expliquer au moyen de l’utilisation de l’analyse spectrale, les mécanismes physiologiques qui sous-tendent la variabilité… (more)

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Cette étude s’inscrit dans les travaux de recherche visant à expliquer au moyen de l’utilisation de l’analyse spectrale, les mécanismes physiologiques qui sous-tendent la variabilité cardiaque. Dans une première étude, nous avons observé les caractéristiques de la variabilité cardiaque chez des sujets âgés de 11 à 59 ans au cours de leur sommeil. Ces enregistrements nous ont permis d’identifier les phases de sommeil lent profond et de mesurer la variabilité cardiaque dans des conditions spontanées reproductibles. Les résultats de cette étude nous ont conduits à nous interroger sur la possibilité d’obtenir une estimation de la fréquence cardiaque intrinsèque (FCI) à partir d’une analyse spectrale des périodes RR mesurées au cours d’un test d’effort incrémenté. Cette estimation serait le moyen de s’extraire des outils pharmacologiques nécessaires actuellement pour mesurer la FCI. Lors d’un exercice physique le contrôle autonome cardiaque est modifié afin de permettre l’augmentation de la FC (retrait vagal dans un premier temps puis activation sympathique). La composante spectrale en hautes fréquences est un indicateur de l’activation du nœud sinusal par le système nerveux parasympathique. La chute brutale de cette composante permet de visualiser le moment d’occurrence du retrait vagal complet. L’identification de ce moment précis nous a été rendue possible par l’utilisation de la méthode temps fréquence de «Pseudo Wigner Ville Lissée» à partir des programmes mis au point par l’INRIA. Cette méthode donne une valeur instantanée de la puissance spectrale en HF. Nous nous sommes alors attachés à mettre au point un protocole d’exercices visant à identifier la fréquence cardiaque au moment où la variabilité cardiaque en haute fréquence est la plus basse ([email protected] pour fréquence cardiaque à la puissance spectrale minimale en haute fréquence). Cette composante représente le moment où le cœur est soumis au minimum d’influences du système nerveux autonome. Elle peut par conséquent représenter une estimation plausible de la FCI. C’est sur ergocycle qu’il est apparu le plus facile de déterminer [email protected] Dans deux études, nous avons ensuite constaté que la différence [email protected] – FC de repos est corrélée à la composante spectrale en HF. [email protected] diminue aussi avec l’âge et est proche des valeurs de la FCI publiées dans la littérature. Enfin, dans une dernière étude, nous avons observé que suite à trois mois d’entrainement de «rugby à toucher», [email protected] diminue chez une population identifiée comme sédentaire au début de l’expérimentation. En conclusion, nous pouvons avancer que l’exercice physique incrémenté combiné à une analyse spectrale instantanée des périodes RR permet d’accéder à une estimation FCI.

This study is part of works about understanding of cardiovascular autonomic control mechanisms using heart rate variability (HRV) analysis. In a first study, we observed HRV from a whole overnight RR periods recordings in order to compare subject from eleven to fifty-nine years old. These recordings allowed to identify Slow Wave…

Advisors/Committee Members: Cottin, François (thesis director).

Subjects/Keywords: Analyse spectrale; Pseudo Wigner Ville Lissé; Fréquence cardiaque intrinsèque; [email protected]; Exercice Physique; Spectral analysis; Smooth pseudo Wigner Ville; Intrinsic heart rate; [email protected]; Physical exercice

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Filliau, C. (2015). Estimation du contrôle nerveux autonome et de l'activité intrinsèque du système cardiaque au moyen de l'analyse de la variabilité des paramètres cardiovasculaires : effets de l'âge et de l’activité physique : Estimation of cardiovascular autonomic conntrol and the intrinsic heart rate from cardiovascular time frequency analysis : Effect of aging ans physical activity. (Doctoral Dissertation). Université Paris-Saclay (ComUE). Retrieved from http://www.theses.fr/2015SACLS193

Chicago Manual of Style (16^th Edition):

Filliau, Christophe. “Estimation du contrôle nerveux autonome et de l'activité intrinsèque du système cardiaque au moyen de l'analyse de la variabilité des paramètres cardiovasculaires : effets de l'âge et de l’activité physique : Estimation of cardiovascular autonomic conntrol and the intrinsic heart rate from cardiovascular time frequency analysis : Effect of aging ans physical activity.” 2015. Doctoral Dissertation, Université Paris-Saclay (ComUE). Accessed January 22, 2021. http://www.theses.fr/2015SACLS193.

MLA Handbook (7^th Edition):

Filliau, Christophe. “Estimation du contrôle nerveux autonome et de l'activité intrinsèque du système cardiaque au moyen de l'analyse de la variabilité des paramètres cardiovasculaires : effets de l'âge et de l’activité physique : Estimation of cardiovascular autonomic conntrol and the intrinsic heart rate from cardiovascular time frequency analysis : Effect of aging ans physical activity.” 2015. Web. 22 Jan 2021.

Vancouver:

Filliau C. Estimation du contrôle nerveux autonome et de l'activité intrinsèque du système cardiaque au moyen de l'analyse de la variabilité des paramètres cardiovasculaires : effets de l'âge et de l’activité physique : Estimation of cardiovascular autonomic conntrol and the intrinsic heart rate from cardiovascular time frequency analysis : Effect of aging ans physical activity. [Internet] [Doctoral dissertation]. Université Paris-Saclay (ComUE); 2015. [cited 2021 Jan 22]. Available from: http://www.theses.fr/2015SACLS193.

Council of Science Editors:

Filliau C. Estimation du contrôle nerveux autonome et de l'activité intrinsèque du système cardiaque au moyen de l'analyse de la variabilité des paramètres cardiovasculaires : effets de l'âge et de l’activité physique : Estimation of cardiovascular autonomic conntrol and the intrinsic heart rate from cardiovascular time frequency analysis : Effect of aging ans physical activity. [Doctoral Dissertation]. Université Paris-Saclay (ComUE); 2015. Available from: http://www.theses.fr/2015SACLS193

University of Vienna

28. Streiter, Lucas Franz. A relativistic Bell test within quantum reference frames.

Degree: 2019, University of Vienna

URL: http://othes.univie.ac.at/58147/

►

Bell Tests werden allgegenwärtig für eine Vielzahl von Anwendungen eingesetzt und sind ein Grundpfeiler sowohl in der Quanteninformation als auch in den Grundlagen der Quantenmechanik.… (more)

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Bell Tests werden allgegenwärtig für eine Vielzahl von Anwendungen eingesetzt und sind ein Grundpfeiler sowohl in der Quanteninformation als auch in den Grundlagen der Quantenmechanik. Die Verletzung der CHSH-Bell Ungleichung durch einen Bell Test zeigt auf grundlegende Art und Weise, dass die Natur mit keiner lokal realistischen Theorie vollständig beschrieben werden kann. Damit ist gezeigt, dass Quantenverschränkung tiefgründiger ist als klassische Korrelationen und dies ermöglicht konkrete Anwendungen, wie z.B. die Quantenteleportation, die klassisch unerklärlich sind. Für einen Bell Test können zwei verschränkte und massive Spin-1/2 Teilchen verwendet werden, deren Spin in raumartig getrennten Gebieten jeweils durch einen Stern- Gerlach-Apparat gemessen wird. Wenn sich die Teilchen jedoch in einer Superposition relativistischer Geschwindigkeiten bewegen, ist die Realisierung eines Bell Tests unbekannt, da in diesem Fall die Spinzustände vom Impuls abhängen und es keine operationelle Definition für die beiden Spinobservablen gibt. In der vorliegenden Arbeit wird eine Lösung für dieses Problem vorgeschlagen, welche Quantenbezugssysteme und die damit ermöglichte Definition des Ruhesystems eines Quantenobjekts benützt. Das Ruhesystem eines Quantenobjekts kann nicht mittels üblicher Transformationen zwischen Bezugssystemen definiert werden, da sich Quantenobjekte im Allgemeinen in einer Superposition von Geschwindigkeiten bewegen. Hier wird diese Limitierung mithilfe von Transformationen zwischen Quantenbezugssystemen überwunden. Somit kann im Ruhesystem eines relativistischen Teilchens dessen Spin, wie in der nicht-relativistischen Quantenmechanik, operationell definiert werden. Die entsprechende Beschreibung in einem anderen (Quanten-)Bezugssystem ergibt sich mittels einer relativistischen Transformation zwischen Quantenbezugssystemen. Auf dieseWeise ergibt sich eine operationelle Definition der beiden Spinobservablen für den Bell Test im Laborbezugssystem, wo sich die beiden massiven Spin-1/2 Teilchen in einer Superposition relativistischer Geschwindigkeiten bewegen. DesWeiteren wird gezeigt, dass die Verletzung der CHSH-Bell Ungleichung, im Gegensatz zu den Spinobservablen, unabhängig vom Bezugssystem ist. Die (maximale) Verletzung der CHSH-Bell Ungleichung zeigt einen möglichen Weg, Quanteninformationsprotokolle operationell auf das relativistische Milieu zu erweitern, wobei (verschränkte) massive Teilchen, die sich in einer Superposition relativistischer Geschwindigkeiten bewegen, als Träger der Quanteninformation dienen.

Bell tests are ubiquitously used for a variety of applications, and have been a cornerstone both in quantum information and quantum foundations. The violation of the CHSH-Bell inequality, by means of a Bell test, shows fundamentally that nature cannot be entirely described with any local realistic theory. This reveals that quantum entanglement is more profound than classical correlations and allows for concrete applications with no classical counterpart,…

Subjects/Keywords: 33.23 Quantenphysik; Quantenbezugssysteme / Bell Test / Bell experiment / Wigner Rotationen / Kanonische TRansformationen / Ruhesystem; quantum reference frames / Bell test / Bell experiment / Wigner rotations / canonical transformations / rest frame

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Streiter, L. F. (2019). A relativistic Bell test within quantum reference frames. (Thesis). University of Vienna. Retrieved from http://othes.univie.ac.at/58147/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Streiter, Lucas Franz. “A relativistic Bell test within quantum reference frames.” 2019. Thesis, University of Vienna. Accessed January 22, 2021. http://othes.univie.ac.at/58147/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Streiter, Lucas Franz. “A relativistic Bell test within quantum reference frames.” 2019. Web. 22 Jan 2021.

Vancouver:

Streiter LF. A relativistic Bell test within quantum reference frames. [Internet] [Thesis]. University of Vienna; 2019. [cited 2021 Jan 22]. Available from: http://othes.univie.ac.at/58147/.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Streiter LF. A relativistic Bell test within quantum reference frames. [Thesis]. University of Vienna; 2019. Available from: http://othes.univie.ac.at/58147/

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

29. CHAN JIA LE. Series expansions in cross-ambiguity functions.

Degree: 2009, National University of Singapore

URL: http://scholarbank.nus.edu.sg/handle/10635/16649

Subjects/Keywords: cross-ambiguity functions; Gabor systems; Wigner and cross-Wigner distributions

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

LE, C. J. (2009). Series expansions in cross-ambiguity functions. (Thesis). National University of Singapore. Retrieved from http://scholarbank.nus.edu.sg/handle/10635/16649

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

LE, CHAN JIA. “Series expansions in cross-ambiguity functions.” 2009. Thesis, National University of Singapore. Accessed January 22, 2021. http://scholarbank.nus.edu.sg/handle/10635/16649.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

LE, CHAN JIA. “Series expansions in cross-ambiguity functions.” 2009. Web. 22 Jan 2021.

Vancouver:

LE CJ. Series expansions in cross-ambiguity functions. [Internet] [Thesis]. National University of Singapore; 2009. [cited 2021 Jan 22]. Available from: http://scholarbank.nus.edu.sg/handle/10635/16649.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

LE CJ. Series expansions in cross-ambiguity functions. [Thesis]. National University of Singapore; 2009. Available from: http://scholarbank.nus.edu.sg/handle/10635/16649

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

30. Beutier, Julien. Development of a quasi-classical method and application to the infrared spectroscopy : Développement d'une méthode quasi-classique et application à la spectroscopie vibrationnelle.

Degree: Docteur es, Physique et Chimie Analytique, 2016, Université Pierre et Marie Curie – Paris VI

URL: http://www.theses.fr/2016PA066207

►

Le calcul de quantités dépendants du temps pour des systèmes quantiques est limité le scaling exponentiel des méthodes exactes. Néanmoins, ces quantités présentes un intérêt… (more)

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Le calcul de quantités dépendants du temps pour des systèmes quantiques est limité le scaling exponentiel des méthodes exactes. Néanmoins, ces quantités présentes un intérêt scientifique important. Un compromis, entre précision et coût, est trouvé par les méthodes quasi-classiques. Dans ces méthodes, la densité thermique exacte est combinée à des trajectoires approximant la dynamique quantique. Durant ma thèse, j’ai développé et appliqué une méthode quasi-classique : PIM (Phase Integration Methode) qui combine des algorithmes MC et MD pour calculer des fonction de corrélation. Le Chapitre 2 décrit les méthodes quasi-classiques ainsi que les approximations qui permettent d’en tirer les fonctions de corrélations dépendants du temps.Le Chapitre 3 illustre comment PIM est adapté au calcul de la densité de Wigner qui est une quantité clé pour les méthodes quasi-classique. À travers le calcul de cette quantité, PIM est capable de capturer des corrélations entre différents degrés de liberté. Dans le Chapitre 4, on montre comment PIM est adapté au calcul de spectres infrarouge. La comparaison des résultats avec d’autres méthodes montre que PIM est une méthode précise pour les systèmes à basse dimensionnalité. Les spectres de OH et CH4 confirment que PIM ne souffrent pas de problèmes intrinsèques comme CMD ou RPMD et peut être appliqué à des systèmes à plus haute dimensionnalité. Le Chapitre 5 présente la méthodologie pour calculer des constantes de vitesse à l’aide de PIM. Les résultats sont bons jusqu’à 300 K mais pas en dessous. Le travail futur se concentrera sur le calcul de la fonction de corrélation de Kubo flux-side pour remédier à ce problème.

Simulation of time-dependent quantities for quantum systems is limited by the exponential scaling of exact methods. However, the calculation of these quantities is key in many problems. A reasonable compromise among accuracy and cost is done by the quasi-classical methods for computing time correlation functions. In these methods, the thermal density is combined with trajectories that approximate quantum dynamics. In my thesis, I develop and apply quasi-classical methods for vibrational spectroscopy. The focus is on the Phase Integration Method. PIM is based on combining MD and MC algorithms to compute appropriate quantities. Chapter 2 is devoted to a general description of the quasi-classical methods. We introduce the different approximations used to compute quantum time correlation functions. Chapter 3 illustrates how PIM is adapted to the calculation of the Wigner density, which is a key quantity in quasi-classical methods. Via this quantity, we show that PIM is able to capture quantum correlation effects among different degrees of freedom. Chapter 4 focuses on the adaptation of PIM for the infrared spectroscopy. Comparison of our results, show that PIM is accurate for low dimensional models. OH and CH4 spectrum confirms that our approach does not suffer from the pathologies such as CMD and RPMD but also that it can treat systems with a larger number of degrees of freedom…

Advisors/Committee Members: Bonella, Sara (thesis director), Borgis, Daniel (thesis director), Vuilleumier, Rodolphe (thesis director).

Subjects/Keywords: Méthode quasi-Classique; Spectroscopie infrarouge; Densité de Wigner; Intégrale de chemin; Dynamique quantique linéarisée; Expansion cumulant; Mixed quantum-classical methods; Infrared spectroscopy; Wigner density; 541.3

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Beutier, J. (2016). Development of a quasi-classical method and application to the infrared spectroscopy : Développement d'une méthode quasi-classique et application à la spectroscopie vibrationnelle. (Doctoral Dissertation). Université Pierre et Marie Curie – Paris VI. Retrieved from http://www.theses.fr/2016PA066207

Chicago Manual of Style (16^th Edition):

Beutier, Julien. “Development of a quasi-classical method and application to the infrared spectroscopy : Développement d'une méthode quasi-classique et application à la spectroscopie vibrationnelle.” 2016. Doctoral Dissertation, Université Pierre et Marie Curie – Paris VI. Accessed January 22, 2021. http://www.theses.fr/2016PA066207.

MLA Handbook (7^th Edition):

Beutier, Julien. “Development of a quasi-classical method and application to the infrared spectroscopy : Développement d'une méthode quasi-classique et application à la spectroscopie vibrationnelle.” 2016. Web. 22 Jan 2021.

Vancouver:

Beutier J. Development of a quasi-classical method and application to the infrared spectroscopy : Développement d'une méthode quasi-classique et application à la spectroscopie vibrationnelle. [Internet] [Doctoral dissertation]. Université Pierre et Marie Curie – Paris VI; 2016. [cited 2021 Jan 22]. Available from: http://www.theses.fr/2016PA066207.

Council of Science Editors:

Beutier J. Development of a quasi-classical method and application to the infrared spectroscopy : Développement d'une méthode quasi-classique et application à la spectroscopie vibrationnelle. [Doctoral Dissertation]. Université Pierre et Marie Curie – Paris VI; 2016. Available from: http://www.theses.fr/2016PA066207

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Open Access Theses and Dissertations