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Lang, Andrew. "The casimir effect /". free to MU campus, to others for purchase, 1998. http://wwwlib.umi.com/cr/mo/fullcit?p9904856.
Pełny tekst źródłaHolmes, Christopher David. "Acoustic Casimir effect". Monterey, California. Naval Postgraduate School, 1997. http://hdl.handle.net/10945/7844.
Pełny tekst źródłaJacobs, David M. "Casimir Localization". Case Western Reserve University School of Graduate Studies / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=case1396608069.
Pełny tekst źródłaRypestøl, Marianne. "Casimir effect in Randall-Sundrummodels". Thesis, Norwegian University of Science and Technology, Department of Physics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-6353.
Pełny tekst źródłaNoto, Antonio. "Non-equilibrium Casimir interactions : from dynamical to thermal effects". Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT279/document.
Pełny tekst źródłaIn this thesis, after an introduction where we briefly present the general context of Casimir physics, we present the results obtained during the PhD. At first, we show our work about the van der Waals/Casimir-Polder interactions between two atoms in an out-of-equilibrium condition due to their uniformly accelerated motion. We study the system of two uniformly accelerated atoms in vacuum space, when they are in their ground-state and when they are in a correlated state (one excited and one ground-state atom). We analyze this system both with an heuristic semiclassical model and with a more rigorous method, based on a separation of radiation reaction and vacuum fluctuations contributions, that we extend starting from a general procedure known in literature. We find a change of the distance-dependence of the interaction due to the acceleration. We show that Casimir-Polder forces between two relativistic uniformly accelerated atoms, interacting with the scalar field, exhibit a transition from the short-distance thermal-like behavior predicted by the Unruh effect to a long-distance nonthermal behavior, associated with the breakdown of a local inertial description of the system. In addition, we obtain new features of the resonance interaction in the case of atoms interacting with the quantum electromagnetic field.Next, we present our work about a new optomechanical coupling of an effectively oscillating mirror with a Rydberg atoms gas, mediated by the dynamical atom-mirror Casimir-Polder force. We find that this coupling may produce a near-field resonant atomic excitation not related to the excitation of atoms by the few real photons expected by dynamical Casimir effect. In accessible experimental conditions, this excitation probability is significant (about 20%) making the observation of this new dynamical Casimir-Polder effect possible. For this reason, we propose a realistic experimental configuration to realize this system made of a cold atom gas trapped in front of a semiconductor substrate, whose dielectric properties are periodically modulated in time.Finally, we focus on our results obtained for the Casimir-Lifshitz pressure between two different dielectric lamellar gratings. This system is assumed to be in an out-of-thermal-equilibrium configuration, i.e. the two gratings have two different temperatures and they are immersed in a thermal bath having a third temperature. The computation of the pressure is based on a method exploiting the scattering operators of the bodies, deduced using the Fourier modal method. In our numerical results we characterize in detail the behavior of the pressure, both by varying the three temperatures and by changing the geometrical parameters of the gratings. In this way we show that it is possible to tune the force from attractive to repulsive or to strongly reduce the pressure for large ranges of temperatures. Moreover, we stress that the interplay between nonequilibrium effects and geometrical periodicity make this system particularly interesting for the observation of the repulsive Casimir force
Haakh, Harald Richard. "Cavity QED with superconductors and its application to the Casimir effect". Master's thesis, Universität Potsdam, 2009. http://opus.kobv.de/ubp/volltexte/2009/3256/.
Pełny tekst źródłaThis thesis investigates the Casimir effect between plates made of normal and superconducting metals over a broad range of temperatures, as well as the Casimir-Polder interaction of an atom to such a surface. Numerical and asymptotical calculations have been the main tools in order to do so. The optical properties of the surfaces are described by dielectric functions or optical conductivities, which are reviewed for common models and have been analyzed with special weight on distributional properties and causality. The calculation of the Casimir energy between two normally conducting plates (cavity) is reviewed and previous work on the contribution to the Casimir energy due to the surface plasmons, present in all metallic cavities, has been generalized to finite temperatures for the first time. In the field of superconductivity, a new analytical continuation of the BCS conductivity to to purely imaginary frequencies has been obtained both inside and outside the extremely dirty limit of vanishing mean free path. The Casimir free energy calculated from this description was shown to coincide well with the values obtained from the two fluid model of superconductivity in certain regimes of the material parameters. The Casimir entropy in a superconducting cavity fulfills the third law of thermodynamics and features a characteristic discontinuity at the phase transition temperature. These effects were equally encountered in the Casimir-Polder interaction of an atom with a superconducting wall. The magnetic dipole coupling of an atom to a metal was shown to be highly sensible to dissipation and especially to the surface currents. This leads to a strong quenching of the magnetic Casimir-Polder energy at finite temperature. Violations of the third law of thermodynamics are encountered in special models, similar to phenomena in the Casimir-effect between two plates, that are debated controversely. None of these effects occurs in the analog electric dipole interaction. The results of this work suggest to reestablish the well-known plasma model as the low temperature limit of a superconductor as in London theory rather than use it for the description of normal metals. Superconductors offer the opportunity to control the dissipation of surface currents to a great extent. This could be used to access experimentally the low frequency optical response of metals, which is strongly connected to the thermal Casimir-effect. Here, differently from corresponding microwave experiments, energy and momentum are independent quantities. A measurement of the total Casimir-Polder interaction of atoms with superconductors seems to be in reach in today’s microchip-based atom-traps and the contribution due to magnetic coupling might be accessed by spectroscopic techniques
Hassan, Arkan Mahmood. "Dynamical Casimir Effect Using Two Photon Absorber". Miami University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=miami1533948476369766.
Pełny tekst źródłavan, Caspel Moos. "The topological Casimir effect on a torus". Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/44948.
Pełny tekst źródłaMcCutcheon, Robert A. "Hybrid Optomechanics and the Dynamical Casimir Effect". Miami University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=miami1501191323617929.
Pełny tekst źródłaFialkovskiy, Ignat. "Efeito Casimir e as propriedades óticas do grapheno". Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-11032013-151501/.
Pełny tekst źródłaThis research is devoted to investigation of several aspects of the physics of suspended and epitaxial graphene monolayers. The description of graphene is based on the quasi--relativistic Dirac model which permits application of the methods of the Quantum Field Theory to investigation of the interaction of graphene with electromagnetic field. Basing on the path integral formalism we formulate the effective theory for EM field in presence of graphene monolayers which is governed by the polarization operator of the Dirac quasi-particles in graphene. The two main phenomena in the interaction of graphene with electromagnetic field are studied: the optical properties of graphene (the Faraday rotation in particular), and Casimir interaction between graphene samples and parallel metal. First, we study the propagation of electromagnetic waves in presence of suspended and epitaxial graphene layers. Their dynamics is governed by the modified Maxwell equations obtained from the effective theory for EM field. We calculate the reflection and transmission coefficient for linearly polarized light and investigate in detail the quantum Faraday effect in external magnetic field. In particular it is showed that the prediction of the Dirac model are in good agreement with recent experimental results on transmission and giant Faraday rotation in cyclotron resonance. New regimes are also predicted Secondly, we investigate Casimir interaction between suspended graphene films with ideal conductor. The effect is investigated both in the idealistic case (zero temperature, ideal samples) and for realistic configurations (non zero temperature and/or presence of impurities and chemical potential). For zero temperature the Casimir force between graphene and a conductor is about 2.7% of that between two ideal conductors. At the same time in the high temperature limit the effect is showed to be greatly enhanced being about 50% of that between ideal metals.
Mackrory, Jonathan. "The Worldline Method for Electromagnetic Casimir Energies". Thesis, University of Oregon, 2017. http://hdl.handle.net/1794/22664.
Pełny tekst źródłaCho, Sung Nae. "Casimir Force in Non-Planar Geometric Configurations". Diss., Virginia Tech, 2004. http://hdl.handle.net/10919/11156.
Pełny tekst źródłaPh. D.
Le, Cunuder Anne. "Étude expérimentale des forces de Casimir". Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEN007/document.
Pełny tekst źródłaThe study of density fluctuations inside confined liquid systems has received the attention of recent theoretical and experimental papers. In order to analyze the role of confinement on the statistical properties of fluctuations, we developed a highly sensitive system where the intensity of fluctuations, as well as their spatial correlation length can be simply tuned. The idea will be to enhance the role of fluctuations working close to the critical temperature Tc of a second order phase transition in a binary mixture. Indeed, the correlation length dramatically increases when one approaches the critical demixion point.The confinement is obtained by using a sphere-plane geometry with a colloidal particle attached to the cantilever of an Atomic Force Microscope (AFM). When the correlation length is comparable with the distance of confinement, Fisher and De Gennes predicted the existence of an interesting effect: the two surfaces will be submitted to either an attracting or a repelling force, depending on boundary conditions. This effect is called the critical Casimir force in reference to the quantum Casimir force resulting from the confinement of quantum fluctuations of the electromagnetic field.During this thesis, we measured the quantum Casimir force between the sphere and the plate, first in a nitrogen atmosphere and then in ethanol, showing that the developed instrument is sufficiently sensible to measure very weak force, of the same order of magnitude or even weaker than the critical Casimir force. Measurements are compared to Lifshitz theory, taking into account the finite conductivity of surfaces
Azari, Arash. "Casimir effect in presence of dielectric and metallic materials". Thesis, University of Sheffield, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.531132.
Pełny tekst źródłaKlatt, Juliane [Verfasser], i Stefan Yoshi [Akademischer Betreuer] Buhmann. "The Casimir-Polder effect and quantum friction across timescales". Freiburg : Universität, 2017. http://d-nb.info/115468184X/34.
Pełny tekst źródłaMessineo, Giuseppe. "The MIR experiment: quantum vacuum and dynamical Casimir effect". Doctoral thesis, Università degli studi di Trieste, 2011. http://hdl.handle.net/10077/4572.
Pełny tekst źródłaThis thesis concerns one of the few low energy experimental efforts aiming to test Quantum Electrodynamics. The experiment MIR (Motion Induced Radiation) studies the quantum vacuum in the presence of accelerated boundaries. According to Quantum Electrodynamics, a non-uniformly accelerated mirror in vacuum feels a friction force due to the interaction with the vacuum photons. As a consequence, real photons are produced in the process, which is known as dynamical Casimir effect. The radiated energy is emitted at the expense of the mechanical energy of the mirror. The effect has never been observed experimentally, since it is very feeble. Only recently a few experimental approaches have been proposed. The theory of the dynamical Casimir effect has been treated extensively in literature. According to the models proposed, for harmonic oscillations the effect is proportional to the oscillation frequency. As all the papers refer to frequencies of the order of a gigahertz, it is not possible to tackle the problem of obtaining a moving boundary with a purely mechanical approach, for example employing piezoelectric transducers or acoustic excitations, due to the large amount of energy required to keep a massive object in motion. A solution to this problem was proposed at the end of the 80's and has been adopted in the MIR experiment. In this framework the moving boundary is a semiconductor slab that switches periodically from complete transparency to total reflection when illuminated by a train of laser pulses. In this way one obtains a time variable mirror which mimics a physical oscillation, without the burden of overcoming the inertia of the mirror. Even so, the number of photons expected is extremely small. The MIR experimental strategy to enhance the photon production is to have the mirror as the wall of a resonating cavity. In this case, if the repetition rate of the laser is about twice a resonance frequency of the cavity, a parametric amplification process occurs, resulting in an enhancement of the number of photons by a factor which depends on the Q-value of the cavity. To this end, superconducting cavities are employed in the experiment.
Questa tesi riguarda uno dei pochi esperimenti di bassa energia dedicati allo studio dell'Elettrodinamica Quantistica. L'esperimento MIR (Motion Induced Radiation) studia il vuoto quantistico in presenza di condizioni al contorno accelerate. Secondo l'Elettrodinamica Quantistica, uno specchio non uniformemente accelerato nel vuoto risente di una forza di attrito dovuta all'interazione con i fotoni del vuoto. In conseguenza di ciò in questo processo, noto come effetto Casimir dinamico, vi è produzione di fotoni reali. L'energia irradiata viene emessa a scapito dell'energia meccanica dello specchio. L'effetto è molto debole e non è mai stato osservato sperimentalmente. Solo di recente sono stati proposti alcuni approcci sperimentali, mentre gli aspetti teorici sono stati trattati ampiamente in letteratura. Secondo i modelli proposti, nel caso di oscillazioni armoniche l'effetto è proporzionale alla frequenza di oscillazione. Poiché tutti gli articoli fanno riferimento a frequenze dell'ordine di un gigahertz, con un approccio puramente meccanico, ad esempio impiegando trasduttori piezoelettrici o eccitazioni acustiche, non è possibile risolvere il problema di ottenere uno specchio in movimento a causa della grande quantità di energia richiesta per mantenere un oggetto massivo in moto. Una soluzione a questo problema è stata proposta alla fine degli anni '80 ed è stata adottata nell'esperimento MIR. L'idea è che la parete in movimento possa essere sostituita da un lastra di semiconduttore che periodicamente passa da uno stato di totale trasparenza ad uno di alta riflettività, per illuminazione da parte di un treno di impulsi laser. In tal modo è possibile ottenere un specchio variabile nel tempo che riproduce una oscillazione fisica, senza la necessità di superare l'inerzia dello specchio. Anche in questo caso tuttavia, il numero di fotoni previsto è estremamente ridotto. La strategia sperimentale di MIR per aumentare la produzione di fotoni è quella di utilizzare lo specchio variabile come parete di una cavità risonante. Se la frequenza di ripetizione del laser è circa due volte la frequenza di risonanza della cavità, si verifica un processo di amplificazione parametrica, con un conseguente aumento del numero di fotoni prodotti. Poiché questo incremento dipende dal Q-valore della cavità, nell'esperimento vengono impiegate cavità superconduttrici.
XXIII Ciclo
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Woolf, David Nathaniel. "Near-Field Optical Forces: Photonics, Plasmonics and the Casimir Effect". Thesis, Harvard University, 2013. http://dissertations.umi.com/gsas.harvard:10812.
Pełny tekst źródłaEngineering and Applied Sciences
Scardicchio, Antonello. "An optical approximation to the Casimir effect and related topics". Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/36811.
Pełny tekst źródłaIncludes bibliographical references (leaves 181-188).
In this thesis, I have studied the dependence of the Casimir force between neutral conductors on their shapes. After reducing the problem to that of finding the density of states of' an appropriate hamiltonian I studied it by using semiclassical methods. Some exemplary geometries of interest for the experiments are studied in detail.
by Antonello Scardicchio.
Ph.D.
NOSARI, GABRIELE. "Local approach to Casimir effect in axiomatic quantum field theory". Doctoral thesis, Università degli studi di Pavia, 2017. http://hdl.handle.net/11571/1203292.
Pełny tekst źródłaBorjan, Zoran. "Application of local functional theory to surface critical phenomena". Thesis, University of Bristol, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302201.
Pełny tekst źródłaObousy, Richard K. Cleaver Gerald B. "Investigation into compactifed dimensions Casimir energies and phenomenological aspects /". Waco, Tex. : Baylor University, 2008. http://hdl.handle.net/2104/5261.
Pełny tekst źródłaGhadirian, Bahman. "A new regularization procedure for calculating the Casimir energy". Thesis, View thesis, 2008. http://handle.uws.edu.au:8081/1959.7/24942.
Pełny tekst źródłaColombaro, Ivano. "Dynamical Casimir effect and the structure of vacuum in quantum field theory". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/10382/.
Pełny tekst źródłaGhadirian, Bahman. "A new regularization procedure for calculating the Casimir energy". View thesis, 2008. http://handle.uws.edu.au:8081/1959.7/24942.
Pełny tekst źródłaA thesis submitted to the University of Western Sydney, College of Health and Science, School of Biomedical and Health Sciences in fulfilment of the requirements for the degree of Doctor of Philosophy. Includes bibliographical references.
Мороз, Ю. В. "Вперше виміряна сила відштовхування в ефекті Казимира-Ліфшиця". Thesis, Сумський державний університет, 2013. http://essuir.sumdu.edu.ua/handle/123456789/41113.
Pełny tekst źródłaCanaguier-Durand, Antoine. "Multipolar scattering expansion for the Casimir effect in the sphere-plane geometry". Paris 6, 2011. http://www.theses.fr/2011PA066246.
Pełny tekst źródłaChiu, Hsiang-Chih. "Demostration of non-additivity ans asymmetry in the lateral Casimir force". Diss., UC access only, 2009. http://proquest.umi.com/pqdweb?index=41&did=1905738741&SrchMode=1&sid=2&Fmt=7&retrieveGroup=0&VType=PQD&VInst=PROD&RQT=309&VName=PQD&TS=1270142776&clientId=48051.
Pełny tekst źródłaIncludes abstract. Includes bibliographical references (leaves 146-154). Issued in print and online. Available via ProQuest Digital Dissertations.
Droujinina, Viola. "On quantum reflection and the Casimir effect application to atom surface scattering /". [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=96859607X.
Pełny tekst źródłaSimpson, William M. R. "Surprises in theoretical Casimir physics : quantum forces in inhomogeneous media". Thesis, University of St Andrews, 2014. http://hdl.handle.net/10023/6338.
Pełny tekst źródłaFermi, D. "A FUNCTIONAL ANALYTIC FRAMEWORK FOR LOCAL ZETA REGULARIZATION AND THE SCALAR CASIMIR EFFECT". Doctoral thesis, Università degli Studi di Milano, 2016. http://hdl.handle.net/2434/360961.
Pełny tekst źródłaMaia, Clóvis Achy Soares [UNESP]. "Fluxos e densidades de energia negativa em teoria quântica de campos". Universidade Estadual Paulista (UNESP), 2005. http://hdl.handle.net/11449/91855.
Pełny tekst źródłaFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Sabe-se já há algum tempo que a Teoria Quântica de Campos permite violações das Condições Clássicas de Energia na forma de densidades e fluxos de energia negativa. Um exemplo contundente é o efeito Casimir, onde o estado de vácuo do campo eletromagnético entre duas placas metálicas possui densidade de energia negativa. Porém, se as leis da física não colocassem restrições sobre tais violações das Condições de Energia, aparentemente seria possível usar energias negativas para, por exemplo, produzir violações macroscópicas da segunda lei da termodinâmica, da conjectura de cosmic censorship, além de se proporcionar a criação de wormholes e possíveis máquinas do tempo. Uma linha de pesquisa desenvolvida para abordar essa questão envolve as chamadas Desigualdades Quânticas, estudadas primeiramente por L.H. Ford, que são desigualdades sobre fluxos e densidades de energia negativa que impõem restrições capazes de tornar as violações acima não observáveis macroscopicamente. Nesta dissertação apresentaremos alguns exemplos de sistemas que possuem densidades ou fluxos de energia negativa, revisaremos os teoremas de Desigualdades Quânticas e discutiremos algumas de suas aplicações. Discutiremos também algumas limitações destes teoremas apresentando sistemas que não estão sujeitos a desigualdades quânticas, dos quais um exemplo é o próprio efeito Casimir. Iremos enfim propor um modelo que introduz flutuações quânticas nas condições de contorno (e.g., nas placas metálicas) do efeito Casimir, e iremos mostrar que a introdução destes efeitos de flutuação no cálculo da energia de Casimir tem por resultado impedir que violações de leis físicas macroscópicas manifeste-se nesse sistema.
Abstracts: It has been known for some time that Quantum Field Theory allows the violation of Classical Energy Conditions in the form of negative energy densities and fluxes. A remarkable exemple is the Casimir effect, where the vacuum state of the electromagnetic field between two perfectly conducting parallel plates presents negative energy density. However, if he laws of physics did not place constraints on such a violation of the Energy Conditions, it appears that it would be possible to use negative energies for producing, for example, macroscopic violation of the second law of thermodynamics, of the cosmic censorship conjecture, and also provide the creation of woemholes and time machines. A line of research wich was developed to approach this question is the so called Quantum Inequalities, first studied by L.H. Ford, which are constraints over negative energy densities and fluxes with capacity to render the above violations macroscopically unobservable. We present here some examples of systems with negative energy densities or fluxes, review the Quantum Inequalities theorems and discuss some of its applications. We also discuss some limitations of these theorems showing systems where there are no quantum inequalities, being the Casimir effect one example. At last we propose a model which introduces quantum fluctuations in the description of the boundaries conditions (e.g., the conducting plates) of Casimir effect and we'll show that the introduction of these fluctuations in the calculation of Casimir energy results in the impossibility of violation of macroscopic physical laws using Casimir configuration.
Ullio, Ícaro Joshua Morales. "Consequências da violação da simetria de Lorentz no Efeito Casimir". Universidade Federal da Paraíba, 2015. http://tede.biblioteca.ufpb.br:8080/handle/tede/8000.
Pełny tekst źródłaMade available in DSpace on 2016-03-16T11:18:29Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 836345 bytes, checksum: 048933d0a290c347efd2fa4764bbcf63 (MD5) Previous issue date: 2015-02-20
In this Dissertation we’ll consider a scalar field theory where the breaking of Lorentz symmetry is present. Basically we will adopt the Ho˘rava-Lifshtz theory. We’ll study the modifications that an anisotropy in space-time produces in the Casimir effect. Let’s deal with a massless real scalar field in two distinct situations: between parallel plates and inside a two-dimensional rectangular box. In both cases we will adopt specific boundary conditions on the field. As we shall see, the Casimir energy and force strongly depends on the parameter associated with the breaking of Lorentz symmetry.
Nesse Dissertação consideraremos uma teoria de campo escalar onde a quebra da simetria de Lorentz está presente. Basicamente adotaremos a teoria de Ho˘rava-Lifshtz. Estudaremos as modificações que uma anisotropia no espaço-tempo produzem no efeito Casimir. Vamos tratar um campo escalar real sem massa em duas situações distintas: entre placas paralelas e no interior de uma caixa bidimensional retangular. Nos dois casos adotaremos condições de contorno específicas sobre o campo. Como veremos, a energia e a força de Casimir dependem fortemente do parametro associado a quebra da simetria de Lorentz.
Laurent, Justine. "Mesures de la force de Casimir à basse température". Phd thesis, Grenoble, 2010. http://www.theses.fr/2010GRENY070.
Pełny tekst źródłaThe Casimir force, named after the Dutch physicist who predicted in 1948 the existence of this attractive force in an ideal conguration of two perfectly conducting and parallel plates, is due to quantum-mechanical effects. It results from electromagnetic fluctuations of vacuum and cannot be neglected anymore in the performance of the nano-mechanical systems (NEMS), which are currently developed and could also revolutionize the microelectronics industry. However, the study of the corrections brought by the surface conductivity or by the dielectric stacks has just started. This thesis work presents the achievement of a new instrument dedicated to the measurement of the Casimir force between two surfaces at the micron scale. We have adapted the technique performed during the G. Jourdan's PhD thesis to a cryogenic environment in order to reach the sensitivity needed to investigate complex surfaces. The viscous damping of the force probe (AFM cantilever) due to the environmental fluid confined between the sphere glued at the tip of the AFM cantilever and a sample has been analysed. Measurements at 4K have revealed an opto-mechanical effect induced by laser noise. Finally, our first tests between two low rough gold surfaces have showed the presence of a parasite force. We have found out the origin of this force and succeeded to remove it. The first measurement of the Casimir force between a gold sphere and a silicon sample has been performed
Baumgärtel, C., i Martin Tajmar. "The Planck Constant and the Origin of Mass due to a Higher Order Casimir Effect". Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-237708.
Pełny tekst źródłaEspinosa, Jorge D. "De-wetting of cobalt thin films on sapphire". Morgantown, W. Va. : [West Virginia University Libraries], 2007. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5314.
Pełny tekst źródłaTitle from document title page. Document formatted into pages; contains ix, 106 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 102-105).
Reis, João Lucas Miqueleto. "Modelos análogos de gravitação semi-clássica usando circuitos supercondutores". reponame:Repositório Institucional da UFABC, 2017.
Znajdź pełny tekst źródłaDissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Física, 2017.
Essa dissertação de mestrado tem por objetivos estudar e discutir as bases matemáticas e conceituais da teoria quântica de campos em espaços-tempos curvos (TQCEC) e analisar como podemos simular efeitos de TQCEC, como o efeito Hawking e o efeito Casimir dinâmico, usando circuitos supercondutores. Após o estudo do formalismo da relatividade geral e da TQCEC, é feita uma revisão sobre os modelos análogos de gravitação em fluidos. Em seguida analisamos a física dos chamados circuitos supercondutores e estudamos como achar análogos de efeitos de TQCEC usando tais sistemas.
This dissertation aims to study and discuss the mathematical and conceptual basis of quantum field theory in curved space-time (QFTCS) and analyse how we can simulate QFTCS effects, such as the Hawking effect and the dynamical Casimir effect, using superconducting circuits. After studying the general relativity formalism and QFTCS, a review is done on analogue models of gravitation in fluids. Then we analyse the physics of the so-called superconducting circuits and study how to find analogues of QFTCS effects using such systems.
Hartmann, Michael [Verfasser], i Gert-Ludwig [Akademischer Betreuer] Ingold. "Casimir effect in the plane-sphere geometry: Beyond the proximity force approximation / Michael Hartmann ; Betreuer: Gert-Ludwig Ingold". Augsburg : Universität Augsburg, 2018. http://d-nb.info/1179089952/34.
Pełny tekst źródłaMaia, Clóvis Achy Soares. "Fluxos e densidades de energia negativa em teoria quântica de campos /". São Paulo : [s.n.], 2005. http://hdl.handle.net/11449/91855.
Pełny tekst źródłaBanca: Élcio Abdalla
Banca: Vitório Alberto De Lorenci
Resumo: Sabe-se já há algum tempo que a Teoria Quântica de Campos permite violações das Condições Clássicas de Energia na forma de densidades e fluxos de energia negativa. Um exemplo contundente é o efeito Casimir, onde o estado de vácuo do campo eletromagnético entre duas placas metálicas possui densidade de energia negativa. Porém, se as leis da física não colocassem restrições sobre tais violações das Condições de Energia, aparentemente seria possível usar energias negativas para, por exemplo, produzir violações macroscópicas da segunda lei da termodinâmica, da conjectura de cosmic censorship, além de se proporcionar a criação de wormholes e possíveis máquinas do tempo. Uma linha de pesquisa desenvolvida para abordar essa questão envolve as chamadas Desigualdades Quânticas, estudadas primeiramente por L.H. Ford, que são desigualdades sobre fluxos e densidades de energia negativa que impõem restrições capazes de tornar as violações acima não observáveis macroscopicamente. Nesta dissertação apresentaremos alguns exemplos de sistemas que possuem densidades ou fluxos de energia negativa, revisaremos os teoremas de Desigualdades Quânticas e discutiremos algumas de suas aplicações. Discutiremos também algumas limitações destes teoremas apresentando sistemas que não estão sujeitos a desigualdades quânticas, dos quais um exemplo é o próprio efeito Casimir. Iremos enfim propor um modelo que introduz flutuações quânticas nas condições de contorno (e.g., nas placas metálicas) do efeito Casimir, e iremos mostrar que a introdução destes efeitos de flutuação no cálculo da energia de Casimir tem por resultado impedir que violações de leis físicas macroscópicas manifeste-se nesse sistema.
Abstracts: It has been known for some time that Quantum Field Theory allows the violation of Classical Energy Conditions in the form of negative energy densities and fluxes. A remarkable exemple is the Casimir effect, where the vacuum state of the electromagnetic field between two perfectly conducting parallel plates presents negative energy density. However, if he laws of physics did not place constraints on such a violation of the Energy Conditions, it appears that it would be possible to use negative energies for producing, for example, macroscopic violation of the second law of thermodynamics, of the cosmic censorship conjecture, and also provide the creation of woemholes and time machines. A line of research wich was developed to approach this question is the so called Quantum Inequalities, first studied by L.H. Ford, which are constraints over negative energy densities and fluxes with capacity to render the above violations macroscopically unobservable. We present here some examples of systems with negative energy densities or fluxes, review the Quantum Inequalities theorems and discuss some of its applications. We also discuss some limitations of these theorems showing systems where there are no quantum inequalities, being the Casimir effect one example. At last we propose a model which introduces quantum fluctuations in the description of the boundaries conditions (e.g., the conducting plates) of Casimir effect and we'll show that the introduction of these fluctuations in the calculation of Casimir energy results in the impossibility of violation of macroscopic physical laws using Casimir configuration.
Mestre
Nefedchenko, Vasyl Fedorovych, Василий Федорович Нефедченко, Василь Федорович Нефедченко i О. Тверезовська. "Ефект Казимира". Thesis, Видавництво СумДУ, 2008. http://essuir.sumdu.edu.ua/handle/123456789/4171.
Pełny tekst źródłaPavlov, Andrei [Verfasser], den Brink Jeroen [Akademischer Betreuer] van, den Brink Jeroen [Gutachter] van, Dmitri [Akademischer Betreuer] Efremov, Werner [Gutachter] Skrotzki, Eduard [Gutachter] Lavrov i Steffen [Gutachter] Sykora. "Phonon-mediated Casimir effect / Andrei Pavlov ; Gutachter: Jeroen van den Brink, Werner Skrotzki, Eduard Lavrov, Steffen Sykora ; Jeroen van den Brink, Dmitri Efremov". Dresden : Technische Universität Dresden, 2019. http://d-nb.info/1227202105/34.
Pełny tekst źródłaBüscher, Rauno. "Casimir forces and geometry". [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=976592533.
Pełny tekst źródłaBellouvet, Maxime. "Condensation de Bose-Einstein et simulation d’une méthode de piégeage d’atomes froids dans des potentiels sublongueur d’onde en champ proche d’une surface nanostructurée". Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0265/document.
Pełny tekst źródłaAn interest for hybrid quantum systems (HSQs) has been growing up for the last decades. This object combines two quantum systems in order to take advantage of both systems’ qualities, not available withonly one. Among these quantum systems, ultracold atoms distinguish themselves by their strong decoupling from environment which enables an excellent control of their intrinsic properties. Optical lattice quantum simulators with tunable properties (energy scale, geometry,...) allows one to investigate new regimes incondensed matter physics. In this quest for exotic quantum phases (e.g., antiferromagnetism), the reduction of thermal entropy is a crucial challenge. The price to pay for such low temperature and entropy is a longthermalization time that will ultimately limit the experimental realization. Miniaturization of lattice spacingis a promising solution to speed up the dynamics. Engineering cold atom hybrids offers promising perspectives but requires us to interface quantum systems in different states of matter at very short distances, which still remains an experimental challenge.This thesis is part of the AUFRONS project, which aims at cooling down an atomic gas until the quantum degeneracy regime then transport and trap this cloud in the near field of a nanostructure. The idea is to trapcold atoms in a two-dimensional subwavelength lattice, at a few tenth of nm away from the surface. One goal is to study atom-atom interactions within the lattice but also atom-surface modes coupling.The work realized during this thesis splits into an experimental part and a theoretical part. In the firstone, we present the cooling of 87Rb atoms until the quantum degeneracy regime. The second part is dedicated to theoretical simulations of a new trapping method we have implemented to trap and manipulate cold atoms below 100 nm from structures. This method takes advantage of plasmonic resonance and vacuum forces (Casimir-Polder effect). It allows one to create subwavelength potentials with controllable parameters.We detail the calculations of optical and vacuum forces to apply them to an atom of 87Rb in the vicinity of a 1D nanostructure
Obadia, Nathaniel. "Le modèle de Davies-Fulling et ses généralisations : un modèle pour la radiation de Hawking". Tours, 2003. http://www.theses.fr/2003TOUR4002.
Pełny tekst źródłaDe, Aquino Carvalho Joao Carlos. "Interaction Casimir-Polder entre atome de césium et surface de saphir thermiquement émissive". Thesis, Sorbonne Paris Cité, 2018. http://www.theses.fr/2018USPCD054.
Pełny tekst źródłaIn this thesis we describe measurements of selective reflection spectroscopy that highlight the thermal effects of the Casimir-Polder interaction between atom and surface. In the near field regime, this interaction is governed by a potential decreasing with the cube of the distance between the atom and the surface (van der Waals -vdW- regime of dipoledipole type) We are particularly interested in the excited levels of cesium, we are particularly interested in the excited levels of cesium Cs (7P₁/₂) and Cs (7P₃/₂), which have a dipole coupling to respectively Cs (6D) at 12,15 µm and ~15 µm interacting with a thermally emissive sapphire surface. Sapphire emitting modes are around 12,2 µm, and, thus, these Cs levels are sensitive to a resonant, or non-resonant, vdW interaction. We compare experimentally these levels. The most important result of this thesis is the experimental observation of the difference in behavior of the vdW potential as a function of the window temperature (150 - 800 °C), for the Cs (7P₁/₂) and Cs (7P₃/₂) levels. For the Cs (7P₁/₂) level the vdW potential increases as a function of temperature, while for the Cs (7P₃/₂) level a slight decrease is observed. Selective reflection spectroscopy experiments, probing the Cs (6P₁/₂) level interacting with a hot sapphire surface, were also carried out, which confirm for this level the absence of a temperature effect. The theoretical predictions are refined by the evaluation of the dielectric constant of sapphire as a function of temperature, from new emissivity data provided by the CEMHTI's group, in Orléans. Finally, we use backscattered fluorescence as a diagnosis for the Cs hot cell when exciting Cs (6P ₁/₂) and Cs (7P ₁/₂) levels. We have interpreted, in a manner more consistent than previous literature, sub-Doppler structures observed in the excitation of the fluorescence near the window
Bugler-Lamb, Samuel Lloyd. "The quantum vacuum near time-dependent dielectrics". Thesis, University of Exeter, 2017. http://hdl.handle.net/10871/29879.
Pełny tekst źródłaDevailly, Clémence. "Fluctuations thermiques - un outil pour étudier les fluides simples et binaires à l'échelle du micron". Thesis, Lyon, École normale supérieure, 2014. http://www.theses.fr/2014ENSL0976.
Pełny tekst źródłaPhase transitions near a critical point, or second order phase transitions, are still a recent object of studies because of the large amount of interesting critical phenomena as the critical Casimir force, confinements problems or out of equilibrium phenomena following a quench at the critical point. This thesis experimentally studies phenomena near a critical point. This manuscript is divided in two parts : the first one consists in building several experimental set-up which measure viscosity through thermal fluctuation at micrometric scale. The second part consists in finding and characterize binary mixtures which show a second order phase transition. Preliminary results have been done in these samples. One of the principal points of these experimental set-up are a well regulated temperature, a probe sensitive to thermal fluctuation and/or pN forces and a reproducible binary mixture which presents a critical point easy to reach experimentally. We mounted from an Atomic Force Microscope (AFM) already built in the laboratory, a hanging-fiber probe to measure viscosity of liquids. Despite its weak efficiency as a metrologic probe, we described and developed a mode coupling model which let us understand mechanics of hanging-fiber probes. I also developed in the lab the dynamic differential microscopy technique (DDM) which do measurements with several probes. I discussed about the measure precision with in mind the aim of studying critical fluctuations. For the choice of the sample, we studied several binary mixtures. We characterized them by classical methods as turbidity measurements and static light scattering. These characterizations let us learn about binary mixtures in order to use them in a third experimental set-up : beads trapped in an optical tweezers already built in the lab. We added to it a home-made thermal regulation which can be used with the constraints of optical tweezers. These tests showed an unexpected phenomenon of oscillating phase transition induce by laser. We developed a model to describe it. At last, preliminary experiments with optical tweezers in binary mixtures showed qualitative effects of an approach near a critical point on the viscosity and on interactions between beads as critical Casimir force
Hertlein, Johann Christopher. "Messung kritischer Casimir-Kräfte mit TIRM". [S.l. : s.n.], 2008. http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-37124.
Pełny tekst źródłaMaury, Axel. "Effet Casimir-Polder sur des atomes piégés". Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066327/document.
Pełny tekst źródłaThis thesis presents the theoretical modeling of the experiment FORCA-G. The purpose of this experiment is to measure short-range interactions between trapped atoms in an optical lattice and a massive surface with a high precision. We are focused on Casimir-Polder effect induced by the surface on the atoms. The aim was to give the most possible precise prediction of atomic states. This work took the temperature effects on Casimir-Polder interaction into account, modelled the surface of the experiment. In order to solve the divergence problem due to the perturbative treatment of the atom-surface interaction, we developed a digital method for a non-perturbative treatment of the Casimir-Polder interaction and modelled the short-range atom-surface interaction by a Lennard-Jones potential. Each effect and uncertainties on the atomic states were evaluated so that we know if they could be observable or a limiting factor compared to the experiment precision. Finally we were focused on an out of thermal equilibrium situation between the miroir and environment temperature which may be induced by the lasers. We computed the correction to the Casimir-Polder potential due to this disequilibrium and evaluated the effect on the atomic states
Busch, Xavier. "Effets dispersifs et dissipatifs en théorie quantique des champs en espace-temps courbe pour modéliser des systèmes de matière condensée". Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112205/document.
Pełny tekst źródłaThe two main predictions of quantum field theory in curved space-time, namely Hawking radiation and cosmological pair production, have not been directly tested and involve ultra high energy configurations. As a consequence, they should be considered with caution. Using the analogy with condensed matter systems put forward by Unruh, their analogue versions could be tested in the lab. Moreover, the high energy behavior of these systems is known and involved dispersion and dissipation, which regulate the theory at short distances. When considering experiments which aim to test the above predictions, the thermal noise will contaminate the outcome. Indeed, there will be a competition between the stimulated emission from thermal noise and the spontaneous emission out of vacuum. In order to measure the quantum analogue Hawking radiation, or the analogue pair production also called dynamical Casimir effect, one should thus compute the consequences of ultraviolet dispersion and dissipation, and identify observables able to establish that the spontaneous emission took place. In this thesis, we first analyze the effects of dispersion and dissipation on both Hawking radiation and pair particle production. To get explicit results, we work in the context of de Sitter space. Using the extended symmetries of the theory in such a background, exact results are obtained. These are then transposed to the context of black holes using the correspondence between de Sitter space and the black hole near horizon region. To introduce dissipation, we consider an exactly solvable model producing any decay rate. In such a model, the field is linearly coupled to an environment containing a dense set of degrees of freedom. We also study the quantum entanglement of the particles so produced. In a second part, we consider explicit condensed matter systems, namely Bose Einstein condensates and exciton-polariton systems. We analyze the effects of dissipation on entanglement produced by the dynamical Casimir effect. As a final step, we study the entanglement of Hawking radiation in the presence of dispersion for a generic analogue system
Intravaia, Francesco. "Effet Casimir et interaction entre plasmons de surface". Phd thesis, Université Pierre et Marie Curie - Paris VI, 2005. http://tel.archives-ouvertes.fr/tel-00009755.
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