Дисертації: "Cold atom physics"

1

Hinton, Andrew George. "Development of a transportable cold atom gradiometer." Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/7120/.

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This work describes the technology developed for the transportable gravity gradiometer, ''GGtop", constructed at the University of Birmingham. The device aims to simultaneously interrogate two physically separated, free-falling cold atom clouds using the technique of Raman interferometry to perform differential gravity measurements. Such a technique will suppress common-mode noise sources, such as vibrations, that otherwise limit classical gravimeters and cold atom interferometers based on single-cloud measurements. The technique is expected to improve speed and sensitivity for field measurements greatly. Using a combination of commercially available components and novel designs, intended to enhance portability and robustness, allowed for demonstration of atomic interference with the apparatus via Ramsey's method of separated oscillatory fields. The achieved fringe contrast of ~2%, defined as the difference in the number of atoms detected in IF = 2 >, was limited by drifts stemming from some of the novel designs which prompted continued optimisation of the underpinning subsystems. To address performance issues parts of the experiment were redesigned with the goal of improving reliability at the expense of some portability. Using the retrofitted experiment, interference was once again achieved with fitted fringe spacing of 134.7±2.0 uS in good agreement with the 133.9 uS defined by the experimental control. A factor of 10 improvement in contrast was found with the central fringe demonstrating 18% of the atoms detected in the IF = 2> state when normalised to the total 3D MOT number. The 3.71 ± 0.01 kHz fitted linewidth of the central fringe gives a frequency uncertainty of 5.43 ± 0.01 x 10 - 7. This result leaves the experiment in a good position to begin making measurements of gravity.

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2

Janovick, Patrick. "PROGRESS TOWARD BUILDING A RATCHET IN COLD ATOM DISSIPATIVELATTICES." Miami University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=miami1533338035196042.

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3

Malcolm, Jonathan Ian. "Construction of a portable platform for cold atom interferometry." Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/6472/.

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This thesis details the construction of a portable platform for cold atom experiments, as part of the European iSense project. This culminated in the demonstration of a working portable cold atom interferometer to the praise of the EC and reviewers during the final project meeting. Reductions in the size, weight and power consumption of all the crucial components for a cold atom system such as lasers, optics, magnetic field generation and electronics have been realised. These novel components have been integrated into a portable device that has been transported and operated by just two people. The completed device weighs 63 kg and uses 240 W power in a volume of just 61.1 litres. The system has generated a cloud of (6.7±0.7)x 10\(^6\) rubidium-87 atoms at a temperature of 4.4 μK in 2 seconds using a mirror-MOT setup. The device has successfully performed atom interferometry in the form of a Ramsey interferometer both at the University of Birmingham, UK and also at an office in Brussels, BE after a journey of 570 km. A measurement of the hyperfine splitting of the ground state of rubidium-87 was performed and gives an uncertainty of \(\delta\)\(\omega\)/\(\omega\) = 5.2 × 10\(^-\)\(^7\). The theoretical limit of the sensitivity to gravity of the iSense system is 3.9 μGal/√Hz.

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4

Rapp, Anthony P. "Numerical simulations of cold atom ratchets in dissipative optical lattices." Miami University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=miami1565625897258688.

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5

Sauer, Jacob A. "Cold Atom Manipulation for Quantum Computing and Control." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/4809.

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Devices that exploit the properties of quantum mechanics for their operation can offer unique advantages over their classical counterparts. Interference of matter waves can be used to dramatically increase the rotational sensitivity of gyroscopes. Complete control of the quantum evolution of a system could produce a new powerful computational device known as a quantum computer. Research into these technologies offers a deeper understanding of quantum mechanics as well as exciting new insights into many other areas of science. Currently, a limiting factor in many quantum devices using neutral atoms is accurate motional control over the atoms. This thesis describes two recent advancements in neutral atom motional control using both magnetic and electromagnetic confining fields. Part I reports on the demonstration of the first storage ring for neutral atoms. This storage ring may one day provide the basis for the world's most sensitive gyroscope. Part II describes the optical delivery of neutral atoms into the mode of a high-finesse cavity for applications in quantum computing and communication.

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6

Burrows, Kathryn Alice. "Non-adiabatic losses from radio frequency dressed cold atom traps." Thesis, University of Sussex, 2016. http://sro.sussex.ac.uk/id/eprint/61380/.

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Cold atom traps are a promising tool for investigating and manipulating atomic behaviour. Radio frequency (RF) dressed cold atom traps allow high versatility of trapping potentials, which is important for potential applications, particularly in atom interferometry. This thesis investigates non-adiabatic spin flip transitions which can lead to losses of atoms from RF-dressed cold atom traps. We develop two models for the adiabatic potentials associated with RF-dressed traps, for the cases in which gravity does and doesn't have a significant effect. Within these two models we use first order perturbation theory to calculate decay rates for the number of dressed spin flip transitions per unit time. Our obtained decay rates are dependent on the atomic energy. For RF-dressed cold atom traps in which spin flip transitions lead to losses of atoms from the trap, we are able to predict ow non-adiabatic transitions decrease the trapped atom number. We achieve this by modelling the atomic distribution of energies for several different scenarios. The thesis concludes with a comparison to experimental data, including modelling how atomic energies are affected by noise in the currents generating the trapping magnetic fields.

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7

Schoene, Elizabeth A. 1979. "Cold atom control with an optical one-way barrier." Thesis, University of Oregon, 2010. http://hdl.handle.net/1794/11067.

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xvi, 176 p. : ill. (some col.)
The research presented in this dissertation aims to contribute to the field of atom optics via the implementation and demonstration of an all-optical one-way barrier for 87 Rb atoms--a novel tool for controlling atomic motion. This barrier--a type of atomic turnstile--transmits atoms traveling in one direction but hinders their passage in the other direction. We create the barrier with two laser beams, generating its unidirectional behavior by exploiting the two hyperfine ground states of 87 Rb. In particular, we judiciously choose the frequency of one beam to present a potential well to atoms in one ground state (the transmitting state) and a potential barrier to atoms in the other state (the reflecting state). The second beam optically pumps the atoms from the transmitting state to the reflecting state. A significant component of the experimental work presented here involves generating ultra-cold rubidium atoms for demonstrating the one-way barrier. To this end, we have designed and constructed a sophisticated 87 Rb cooling and trapping apparatus. This apparatus comprises an extensive ultra-high vacuum system, four home-built, frequency-stabilized diode laser systems, a high-power Yb:fiber laser, a multitude of supporting optics, and substantial timing and control electronics. This system allows us to cool and trap rubidium atoms at a temperature of about 30 μK. The results presented in this dissertation are summarized as follows. We successfully implemented a one-way barrier for neutral atoms and demonstrated its asymmetric nature. We used this new tool to compress the phase-space volume of an atomic sample and examined its significance as a physical realization of Maxwell's demon. We also demonstrated the robustness of the barrier's functionality to variations in several important experimental parameters. Lastly, we demonstrated the barrier's ability to cool an atomic sample, substantiating its potential application as a new cooling tool. This dissertation includes previously published coauthored material.
Committee in charge: Dr. Hailin Wang, Chair; Dr. Daniel A. Steck, Research Advisor; Dr. Jens U. Nockel; Dr. David M. Strom; Dr. Jeffrey A. Cina

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8

Reinhed, Peter. "Ions in cold electrostatic storage devices." Doctoral thesis, Stockholm : Department of physics, Stockholm University, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-32659.

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Diss. (sammanfattning) Stockholm : Stockholms universitet, 2010.
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Submitted. Härtill 4 uppsatser.

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9

Gadge, Amruta. "A cold atom apparatus for the microscopy of thin membranes." Thesis, University of Nottingham, 2018. http://eprints.nottingham.ac.uk/49881/.

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Ultracold atomic gases can be utilised as extremely sensitive probes of their surrounding environment. In particular, samples of ultracold atoms confined using chip-based microtraps are an ideal tool for mapping electric and magnetic field landscapes. Over the course of this thesis, a new experiment capable of performing surface microscopy using magnetically trapped clouds of cold rubidium-87 atoms has been built. The focus of the work is on the design and construction of the experimental system, which must incorporate many different aspects for manipulating thermal atomic gases, with a view to positioning them at sub-micron distances from special surfaces. This reduced atom-surface separation is necessary for implementing a high resolution, high sensitivity magnetic field sensor with cold atoms. Although current microfabrication techniques easily enable trapping at distances on the order of micrometres, several distance-dependent surface effects - such as the Casimir-Polder force, Johnson-Nyquist noise, and stray potentials - eventually impede magnetic trapping at the sub-micron level. These surface effects can greatly modify the confining potentials, which reduces the trap depth and consequently leads to an additional loss rate of atoms from the trap. We have explored the possibility of using special surfaces such as nano-membranes of silicon nitride and graphene, which have reduced atom- surface interactions, to enable trapping distances at the sub-micron level. A multilayer printed circuit board chip has been designed to form an initial magnetic trap and then transport the cloud of atoms to a desired location over the samples. This chip, along with various samples, is mounted on a custom-made electrical feedthrough designed to make connections to all conductor that are inside the vacuum chamber. The initial cloud of cold atoms can then be prepared in the central region of the chip and delivered to the location of the samples on either side. The experimental system is able to routinely capture over 10^8 rubidium-87 atoms at a temperature of 80 micro-Kelvin in a magneto-optical trap using a novel scheme of five laser beams. A method is demonstrated for enhancing the atom number in the magneto-optical traps by a factor of two by using laser beams with two slightly different frequencies. Atoms from the magneto-optical trap are then transferred to a purely magnetic trap formed by the wires on the printed circuit board chip. Time-dependent currents in the chip wires then create a dynamic potential, which is shown to successfully transport the atomic sample over a distance of 12 millimetre with minimal atom loss. This thesis describes the development of the apparatus in detail, along with careful characterisation of the cold cloud at various stages of the experimental sequence. Initial results on the long distance atom transport are presented. Finally, the experimental results of the two frequency magneto-optical trap for atom number improvement are discussed.

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10

Dauphin, Alexandre. "Cold atom quantum simulation of topological phases of matter." Doctoral thesis, Universite Libre de Bruxelles, 2015. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209076.

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L'étude des phases de la matière est d'un intérêt fondamental en physique. La théorie de Landau, qui est le "modèle standard" des transitions de phases, caractérise les phases de la matière en termes des brisures de symétrie, décrites par un paramètre d'ordre local. Cette théorie a permis la description de phénomènes remarquables tels que la condensation de Bose-Einstein, la supraconductivité et la superfluidité.

Il existe cependant des phases qui échappent à la description de Landau. Il s'agit des phases quantiques topologiques. Celles-ci constituent un nouveau paradigme et sont caractérisées par un ordre global défini par un invariant topologique. Ce dernier classe les objets ou systèmes de la manière suivante: deux objets appartiennent à la même classe topologique s'il est possible de déformer continument le premier objet en le second. Cette propriété globale rend le système robuste contre des perturbations locales telles que le désordre.

Les atomes froids constituent une plateforme idéale pour simuler les phases quantiques topologiques. Depuis l'invention du laser, les progrès en physique atomique et moléculaire ont permis un contrôle de la dynamique et des états internes des atomes. La réalisation de gaz quantiques,tels que les condensats de Bose-Einstein et les gaz dégénérés de Fermi, ainsi que la réalisation de réseaux optiques à l'aide de faisceaux lasers, permettent d'étudier ces nouvelles phases de la matière et de simuler aussi la physique du solide cristallin.

Dans cette thèse, nous nous concentrons sur l'etude d'isolants topologiques avec des atomes froids. Ces derniers sont isolants de volume mais possèdent des états de surface qui sont conducteurs, protégés par un invariant topologique. Nous traitons trois sujets principaux. Le premier sujet concerne la génération dynamique d'un isolant topologique de Mott. Ici, les interactions engendrent l'isolant topologique et ce, sans champ de jauge de fond. Le second sujet concerne la détection des isolants topologiques dans les expériences d'atomes froids. Nous proposons deux méthodes complémentaires pour caractériser celles-ci. Finalement, le troisième sujet aborde des thèmes au-delà de la définition standard d'isolant topologique. Nous avons d'une part proposé un algorithme efficace pour calculer la conductivité de Berry, la contribution topologique à la conductivité transverse lorsque l'énergie de Fermi se trouve dans une bande d'énergie. D'autre part, nous avons utilisé des méthodes pour caractériser les propriétés quantiques topologiques de systèmes non-périodiques.

L'étude des isolants topologiques dans les expériences d'atomes froids est un sujet de recherche récent et en pleine expansion. Dans ce contexte, cette thèse apporte plusieurs contributions théoriques pour la simulation de systèmes quantiques sur réseau avec des atomes froids.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished

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11

Doherty, William Gerard. "Cold atom production via the photo dissociation of small molecules." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:523f87e0-3f19-4382-941c-74b06023b767.

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This thesis describes the development of a relatively novel technique for the gen- eration and subsequent trapping of cold species. Molecules in a pulsed supersonic expansion are photolysed, such that the centre-of-mass velocity vector of one of the fragments is equal in magnitude but opposed in orientation to the lab-frame velocity of the precursor molecule. This technique, known as ‘Photostop’, leaves a fraction of the fragments with a narrow velocity distribution, centered around zero velocity in the lab-frame. They can be shown to have zero velocity by changing the time between photodissociation and ionisation; fragments with a high kinetic energy will leave the ionisation volume prior to interrogation. The underlying velocity distribu- tion is uncovered by using the velocity-map imaging technique, and the temperature of the fragments can be determined. The method was originally optimised for the molecular case. Cold NO has been produced from the dissociation of NO₂ molecules, and a single rotational state has been shown to remain in the ionisation volume 10 μs after dissociation, implying a sample temperature of 1.17 K. Using the optimised experimental conditions de- rived from the velocity cancellation of NO, the atomic case is demonstrated for the dissociation of Br₂ to give zero-velocity Br fragments. The Br atoms are seen for delay times in excess of 100 μs, showing the greater applicability of the method to the atomic case. The temperature of the residual atoms is shown to be in the milliKelvin regime, as determined through detailed Monte Carlo simulation of the motion of the stopped atoms. The possibility of trapping the ultracold Br atoms in a magnetic field is explored, and a quadrupolar trap created between two per- manent bar magnets is demonstrated to confine the atoms spatially, within the ion extraction optics, for delays in excess of 1 ms. The Photostop technique is intended to be a stepping stone on the way to widening the number of chemical species available for study in the ultracold regime. The possibility of improvements to the experiment is considered, in order to increase the efficiency of the experiment such that the number density becomes high enough to be viable as a source of atoms for use in cold chemical reactive studies. The possibility of extending the method so as to be used as a tunable velocity source of atoms is also discussed.

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12

Gillette, Matthew Charles. "Design and Implementation of an Inexpensive Fast Imaging System for Cold Atom Experiments." Miami University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=miami1406925645.

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13

Walker, Graeme. "Trans-spectral transfer of orbital angular momentum and creation of an ultra high density cold atom trap." Thesis, University of Glasgow, 2013. http://theses.gla.ac.uk/4498/.

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In recent years there has been great interest in the applications of the interaction of the phase and intensity of laser light in atomic vapours. The generation of light beams with arbitrary phase and intensity patterns can now be easily achieved by using Spatial Light Modulators (SLMs). The transformation of quantized units of phase information to atomic vapours has implications in the ﬁelds of quantum optics for the realisation of sources of entangled photons, optical switching, and quantum information storage. Spatially shaped beams with non-trivial intensity geometries have found use in single atom quantum well traps and for the enhancement of density of standard Magneto Optical Traps. The work in this thesis is focussed around two main pro jects, involving the interaction of holographically shaped light beams with cold trapped atoms and with a hot atomic vapour respectively. An enhancement to the previously investigated technique of a SPontaneous force Optical Trap SPOT of 87 Rb is presented here which aims to solve various issues which naturally arise from compressing cold atoms in a Magneto Optical Trap (MOT) such as unavoidable heating during the compression. High density/high atom number traps are highly sought after in many experiments for more eﬃcient transfer of atoms to Bose Einstein Condensates and for improved quantum storage capabilities in cold atom traps. The highest density achieved in our SPOT was 2.5 × 10^12 atoms cm−3 for 2 × 10^8 atoms at a temperature of approximately 100µK. This represents almost 2 orders of magnitude increase in density from the standard MOT setup with no adverse heating of the trap while maintaining 75% of the atoms. In the second part of this work hot atomic vapours are utilized for the eﬃcient transfer of orbital angular momentum information from near infra-red pump ﬁelds, driving from 5S_1/2 to 5D_5/2 on a two-photon transition, to a cascade from 5D_5/2 to 6P_3/2 to 5S_1/2 generating 5230nm light and a coherent blue, 420nm, beam respecitively. This generation is performed using four wave mixing in 85 Rb. We observe the complete conversion of all input quantum information, the Orbital Angular Momentum (OAM) from the pump ﬁelds to the blue. In addition we show the additional phase coherence eﬀects of this experiment through the use of simple superpositions of Laguerre-Gaussian (LG) modes showing that the process is indeed quantum in nature. A theoretical basis for the transfer of all OAM information to only the 420nm beam is also discussed here.

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14

Dharmasiri, Ajithamithra. "PRELIMINARY OBSERVATION OF VIBRATIONAL RESONANCES ANDPROPAGATION MODES IN COLD ATOM DISSIPATIVE 3D OPTICAL LATTICES." Miami University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=miami1565364321993546.

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15

Lefèvre, Grégoire. "Développement d’un interféromètre atomique en cavité pour le projet MIGA." Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0063/document.

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Après plusieurs décennies de développement, l'interférométrie atomique est devenue un outil extrêmement performant pour mesurer des effets inertiels, tels que des accélérations et des rotations. De telles techniques sont maintenant envisagées pour une future génération de détecteurs d'ondes gravitationnelles afin de pousser les limites de l'état de l'art des détecteurs actuels. L'instrument MIGA (Matter-wave laser Interferometer Gravitation Antenna) couplera interférométrie atomique et optique pour étudier des perturbations du champ gravitationnel à basse fréquence (Hz et sub-Hz). Il consistera en un réseau de 3 interféromètres atomiques, simultanément interrogés par le champ électromagnétique résonnant au sein de deux cavités optiques de 150 m de long, en utilisant un ensemble d'impulsions de Bragg d'ordre π/2 - π - π/2. Des mesures gradiométriques permettront d'acquérir une forte immunité aux bruits sismique et newtonien, qui sont limitants pour les détecteurs terrestres optiques tels que LIGO et Virgo. Une expérience préliminaire est en développement au LP2N, à Talence (France), où un interféromètre est interrogé par deux cavités de 80 cm de long. Pour avoir une taille de faisceau suffisante afin d'interroger efficacement les atomes de 87Rb dans des cavités de cette longueur, nous utilisons une géométrie de cavité marginalement stable, constituée de deux miroirs plans situés à la focale d'une lentille biconvexe, où un mode gaussien de rayon de plusieurs mm peut résonner
After few decades of development, atom interferometry has become an extremely efficient tool for measuring inertial effects such as accelerations and rotations. Such techniques are now envisioned for a future generation of gravitational wave detectors to push further the limit of the current optical detectors. The Matter-Wave Laser Interferometer Gravitation Antenna (MIGA) instrument will couple atom and optical interferometry to study perturbations of the gravitational field at low-frequencies (Hz and sub-Hz). It will consist of an array of 3 atom interferometers, simultaneously interrogated by the light field resonating inside two 150 m long optical cavities, using a set of high order Bragg pulses π/2 - π - π/2. Gradiometric measurements allows a strong immunity to seismic and newtonian noises which limit optical ground-based detectors such as LIGO and Virgo. A preliminary experiment is being developed at the LP2N laboratory, in Talence (France), where a single atomic cloud is interrogated inside two 80 cm long cavities. In order to interrogate efficiently the 87Rb atoms, a gaussian beam with a radius of several mm resonating inside these cavities is required. This can be achieved by using a marginally stable cavity geometry, composed by two plane mirrors located in the focal planes of a biconvex lens

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16

Liao, Renyuan. "Fermion Pairing and BEC-BCS Crossover in Novel Systems." Kent State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=kent1220882883.

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17

Huang, Biao. "Exploring New Physics in Ultracold Quantum Gases: High Spin Fermions and Non-Trivial Background Manifolds." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1468280791.

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18

Keilmann, Tassilo. "Strongly correlated quantum physics with cold atoms." Diss., lmu, 2009. http://nbn-resolving.de/urn:nbn:de:bvb:19-107331.

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19

Kime, Leila. "Production d'une source d'ions césium monocinétique basée sur des atomes refroidis par laser en vue d'un couplage avec une colonne à faisceaux d'ions focalisés." Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00781962.

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Cette thèse porte sur l'étude de la production d'une source d'ionsCes travaux de thèse ont consisté à étudier la faisabilité d'une source d'ions césium brillante et de faible dispersion énergétique à partir d'atomes froids dans le but de la coupler à une optique de faisceau d'ions focalisés (FIB).Il s'agit de produire une source ionique continue, de fort courant et de plus faible dispersion en énergie que les sources actuellement utilisées. Un schéma expérimental innovant a donc été imaginé.Un flux continu d'atomes de césium est issu d'un four à recirculation. Les atomes sont ensuite collimatés et compressés en se basant su les techniques de refroidissement d'atomes par laser. Des simulations de la mélasse optique pour la collimation et du MOT-2D pour la compression sont présentées. Issus d'un jet effusif de césium produit par un four à recirculation, la collimation grâce à une mélasse optique et la compression effectuée en en utilisant un MOT-2D des atomes de césium a été étudiée. Le schéma d'ionisation des atomes de césium passe par une excitation vers un état de Rydberg puis par une ionisation par champ électrique. Les propriétés remarquables des atomes pour ces niveaux d'énergie permettent d'obtenir une ionisation des atomes en champ électrique quasi-instantanée qui permet la minimisation de la dispersion énergétique. Nous avons développer une simulation permettant d'étudier les propriétés du champ électrique nécessaire pour l'ionisation afin de choisir le niveau de Rydberg approprié. Des simulations complémentaires ont permis de définir et de concevoir les électrodes nécessaires à la production du champ électrique d'excitation et d'ionisation. Une première étude des effets coulombiens de la source d'ions lors de l'ionisation des atomes de Rydberg est présentée. Enfin, l'étude théorique du couplage de la source obtenue avec une optique de faisceaux d'ions focalisés est réalisée.Un montage expérimental vient compléter ces diverses études et a permis d'obtenir les premiers résultats.

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20

Côté, Joseph Noël Robin. "Ultra-cold collisions of identcial atoms." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/32632.

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21

Meister, Matthias [Verfasser]. "Novel concepts for ultra-cold quantum gases in microgravity : equal trap frequencies, atoms trapped by atoms, and the space atom laser / Matthias Meister." Ulm : Universität Ulm, 2019. http://d-nb.info/120207653X/34.

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22

Mudarikwa, Lawrence. "Cold atoms in a ring cavity." Thesis, University of Birmingham, 2015. http://etheses.bham.ac.uk//id/eprint/5843/.

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An ensemble of atoms coupled to a high finesse optical cavity is an ideal test bed for the study of the cooperative behaviour of atom-photon systems. Dicke showed that an ensemble of excited atoms coupled to a light field interacts with the light in a collective and coherent fashion leading to the emission of highly directional spontaneous emission whose intensity scales with the square of the number of atoms, a phenomenon known as superradiance. This thesis describes the build of an experiment to study cooperative atom-photon interactions in a ring cavity. Particular focus is given to the cavities used in the experiment. Firstly a transfer cavity used for transferring stability to off-resonant lasers in the experiment, this was developed with the capability of exploiting Gouy phase degeneracies to produce tightly spaced frequency discriminants to be used as lock points. Secondly the ring cavity for the experiment which is atypical in its design allowing for bidirectional probing of the cavity mode and dynamic manipulation of the intra-cavity optical lattice. An intra-cavity MOT was produced and collective strong coupling was observed in the cavity with an Neff=6400 atoms coupled to the cavity mode.

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23

Drayna, Garrett Korda. "Novel Applications of Buffer-Gas Cooling to Cold Atoms, Diatomic Molecules, and Large Molecules." Thesis, Harvard University, 2016. http://nrs.harvard.edu/urn-3:HUL.InstRepos:26718757.

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Cold gases of atoms and molecules provide a system for the exploration of a diverse set of physical phenomena. For example, cold gasses of magnetically and electrically polar atoms and molecules are ideal systems for quantum simulation and quantum computation experiments, and cold gasses of large polar molecules allow for novel spectroscopic techniques. Buffer-gas cooling is a robust and widely applicable method for cooling atoms and molecules to temperatures of approximately 1 Kelvin. In this thesis, I present novel applications of buffer-gas cooling to obtaining gases of trapped, ultracold atoms and diatomic molecules, as well as the study of the cooling of large organic molecules. In the first experiment of this thesis, a buffer-gas beam source of atoms is used to directly load a magneto-optical trap. Due to the versatility of the buffer-gas beam source, we obtain trapped, sub-milliKelvin gases of four different lanthanide species using the same experimental apparatus. In the second experiment of this thesis, a buffer-gas beam is used as the initial stage of an experiment to directly laser cool and magneto-optically trap the diatomic molecule CaF. In the third experiment of this thesis, buffer-gas cooling is used to study the cooling of the conformational state of large organic molecules. We directly observe conformational relaxation of gas-phase 1,2-propanediol due to cold collisions with helium gas. Lastly, I present preliminary results on a variety of novel applications of buffer-gas cooling, such as mixture analysis, separation of chiral mixtures, the measurement of parity-violation in chiral molecules, and the cooling and spectroscopy of highly unstable reaction intermediates.
Chemical Physics

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24

Scott, Robin George. "Cold atoms in optical lattices." Thesis, University of Nottingham, 2003. http://eprints.nottingham.ac.uk/10010/.

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This thesis describes the behaviour of cold atoms in optical lattices. In particular, it explores how transport through the energy bands of the optical lattice can be used to study quantum chaos and Bose-Einstein condensation. Firstly, this study examines the dynamics of ultra-cold sodium atoms in a one-dimensional optical lattice and a three-dimensional harmonic trap, using both semi-classical and quantum-mechanical analyses. The atoms show mixed stable-chaotic classical dynamics, which originate from the intrinsically quantum-mechanical nature of the energy band. The quantised energy levels exhibit Gutzwiller fluctuations, and the wavefunctions are scarred by an unstable periodic orbit. Distinct types of wavefunction are identified and related directly to particular parts of the classical phase space via a Wigner function analysis. Secondly, this report studies the dynamics of a rubidium Bose-Einstein condensate in a one-dimensional optical lattice and three-dimensional harmonic trap. The condensates are set in motion by displacing the trap and initially follow simple semi-classical paths, shaped by the lowest energy band. Above a critical displacement, the condensate undergoes Bragg reflection, and performs Bloch oscillations. After multiple Bragg reflections, solitons and vortices form which damp the centre-of-mass motion. Finally, the dynamics of Bose-Einstein condensates in optical lattices are investigated for different parameter regimes, as realised in recent experiments. The results reveal how the experiments can be understood, and identify regimes in which vortices trigger explosive expansion of the condensate.

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25

Perea-Ortiz, Marisa. "Progress towards a quantum simulator with cold atoms." Thesis, University of Birmingham, 2015. http://etheses.bham.ac.uk//id/eprint/5774/.

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This thesis presents work toward a quantum simulator with cold atoms. Characteristic and defining subsystems of the experimental setup are presented. Among them there are: the self-made viewports for ultra-high vacuum using indium seals, work on a modular laser system, for laser cooling, with miniaturised optics for the optimization of double path acusto-optic modulator. Work on a computer control to implement past slot is also presented. A versatile detection system for absorption imaging was designed and built. This detection system is stable, easy to align and exchange of magnification is simple. As well, a high resolution imaging system was designed, built and tested. This imaging system uses commercial microscope objectives and has been designed to work with four different microscope objective. Magnification of 5x, 10x 20x and 50x are possible. With the maximum magnification of 50x a resolution of 1.74μm for 780nm was achieved. Also a camera control for in-situ absorption imaging was programmed. Calculation of number of atoms and temperature were implemented in the program, as well as a defringing algorithm. A new method for temperature calculation for atoms held in a magnetic quadrupole trap was developed and tested, giving similar calculation of temperature as the commonly known time of flight (TOF) method. It is shown that this new method gives better results than the common TOF method for short time of flight. Characterization of atom losses and heating in the production of a Bose-Einstein condensate were performed.

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26

Rammeloo, Clemens Vincent. "Optimisation of a compact cold-atoms interferometer for gravimetry." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8146/.

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The work presented in this thesis focusses on the development of a transportable atom-interferometry experiment and a compact fibre laser system towards precision measurements of gravitational acceleration. Interference fringes are shown with clouds of cold 87Rb atoms using co-propagating laser beams to drive stimulated Raman transitions. This is demonstrated both inside and outside of laboratory environments for which an integrated and transportable experiment is constructed. Further improvements are presented that enable the generation of clouds containing 1.7 · 108 atoms at a rate of 2.5 Hz and having a temperature of (7 ± 1) μK. This is largely due to the development of a compact laser system based on all-fibre coupled components. It is demonstrated that the laser system designed here can achieve fast frequency sweeps over 1.8 GHz within 2 ms, making it widely applicable in compact atom-interferometry experiments with rubidium atoms. This is shown by creating a Mach–Zehnder type interferometer with counter-propagating Raman beams, thus enabling measurements of gravitational acceleration. Since the laser system uses only two lasers and one fibre amplifier, a significant reduction in size is achieved, as well as a decrease in the total power consumption of the overall experiment by a third to (162 ± 7) W.

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27

Stroescu, Ion [Verfasser], and Markus [Akademischer Betreuer] Oberthaler. "Dissipative Double-Well Potential: Mesoscopic Atom Number Detection and Cold Atom Dynamics / Ion Stroescu ; Betreuer: Markus Oberthaler." Heidelberg : Universitätsbibliothek Heidelberg, 2014. http://d-nb.info/1179925823/34.

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28

Krükow, Artjom [Verfasser]. "Three-body reaction dynamics in cold atom-ion experiments / Artjom Krükow." Ulm : Universität Ulm, 2017. http://d-nb.info/1133171419/34.

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29

Song, Jianjun. "Optically generated gauge potentials and their effects in cold atoms /." View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?PHYS%202008%20SONG.

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30

Zhu, Lingziao. "A cold atoms gravimeter for use in absolute gravity comparisons." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8152/.

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This thesis describes the construction of high precision absolute gravimeter, aiming at realising a comparison with a state-of-the-art gravimeter. The instrument is based on performing Raman atom interferometry on ensembles of laser-cooled 87Rb atoms in an atomic fountain. The highlight of this work is the demonstration of an IQ modulator based optical single-sideband (OSSB) laser system providing a highly coherent light source. The advantage this brings to atom interferometry is the suppression of the unwanted sidebands, eliminating interference effects, especially the spatially dependent Rabi frequency and the interferometric phase shift. Recently 5x106 atoms were launched at a rate of 0.5 Hz with a temperature of 10 �K. After improving the vibration isolation, we have observed interference fringes with a sensitivity of 225 �Gal/pHz. The preliminary accuracy is estimated to be 218 �Gal. A study of systematic noise and bias sources has been undertaken, �finding that the limitation of the above performance is the vibration noise and Coriolis effect, respectively. The apparatus has been transported to NERC Space Geodesy Facility in Herstmonceux, where a comparison campaign is in preparation.

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31

Zhang, Dongqing. "Aspects of cold bosonic atoms with a large scattering length." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1164823171.

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32

Hucul, David (David Alexander). "Magnetic super-exchange with ultra cold atoms in spin dependent optical lattices." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/58068.

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Анотація:

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Physics, 2009.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 65-68).
The methods of atomic physics offer a unique opportunity to study strongly correlated many body systems. It is possible to confine BECs in periodic optical lattices to form an analog of a solid state system. The study of these cold atoms in optical lattice systems may prove a very useful testing ground for novel states of matter, testing fundamental condensed matter theory, and may help illuminate a possible connection between the mechanism behind high temperature superconductivity and quantum magnetism. This thesis will focus on trapping cold bosonic atoms in spin dependent optical lattices to engineer a system that behaves according to the Hubbard model. By loading the atoms into a state dependent lattice, it may be possible to explore the full phase space of the Heisenberg model and see magnetic super exchange-driven magnetic ordering in a variety of lattice geometries. The aim of this thesis is primarily to explore some of the tools that may be needed accomplish this task.
by David Hucul.
S.M.

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33

Wendrich, Thijs Jan [Verfasser]. "High resolution rotation sensor based on cold atom interferometry / Thijs Jan Wendrich." Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover, 2010. http://d-nb.info/1008684694/34.

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34

Hachtel, Andrew J. "Creation and Detection of a 1D Optical Lattice of ⁸⁵Rb Atoms Using a Low-Cost Camera and Imaging System." Miami University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=miami1407511483.

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35

Ménoret, Vincent. "Accéléromètre à atomes froids aéroporté pour un test du Principe d'Equivalence." Phd thesis, Université Paris Sud - Paris XI, 2012. http://tel.archives-ouvertes.fr/tel-00747538.

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Dans ce mémoire, nous présentons l'étude d'un senseur inertiel à ondes de matière embarqué dans un avion effectuant des vols paraboliques.Une source laser bi-fréquence robuste et compacte permettant de refroidir et d'interroger simultanément des atomes de 87Rb et 39K a été développée. Elle est basée sur des lasers télécom asservis sur un peigne de fréquences optique et doublés en fréquence. L'utilisation de composants optiques fibrés permet de rendre le système intrinsèquement résistant aux vibrations et aux fluctuations thermiques. Le dispositif a été validé en vol par l'obtention d'un double piège magnéto-optique.Nous avons utilisé la source laser pour faire fonctionner un interféromètre à atomes froids de 87Rb dans l'avion. Un accéléromètre mécanique auxiliaire permet d'augmenter la dynamique du capteur atomique et d'enregistrer des franges d'interférences malgré le niveau élevé des fluctuations d'accélération. Le senseur hybride ainsi réalisé a une résolution de 4.10-3 m.s-2.Hz-1/2, environ 100 fois plus faible que le niveau des vibrations dans l'avion.Dans la perspective de réaliser un test du principe d'équivalence en microgravité avec des atomes froids, nous étudions enfin de manière théorique le fonctionnement d'un interféromètre différentiel et nous intéressons à l'influence de certains effets systématiques.

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36

Rehn, Magnus. "Experimental and Numerical Investigations of Ultra-Cold Atoms." Doctoral thesis, Umeå : Department of Physics, Umeå Univ, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1453.

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37

Johnson, Tomi Harry. "Non-equilibrium strongly-correlated dynamics." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:55d438cc-d9a1-4898-ac05-49299bad6806.

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We study non-equilibrium and strongly-correlated dynamics in two contexts. We begin by analysing quantum many-body systems out of equilibrium through the lens of cold atomic impurities in Bose gases. Such highly-imbalanced mixtures provide a controlled arena for the study of interactions, dissipation, decoherence and transport in a many-body quantum environment. Specifically we investigate the oscillatory dynamics of a trapped and initially highly-localised impurity interacting with a weakly-interacting trapped quasi low-dimensional Bose gas. This relates to and goes beyond a recent experiment by the Inguscio group in Florence. We witness a delicate interplay between the self-trapping of the impurity and the inhomogeneity of the Bose gas, and describe the dissipation of the energy of the impurity through phononic excitations of the Bose gas. We then study the transport of a driven, periodically-trapped impurity through a quasi one-dimensional Bose gas. We show that placing the weakly-interacting Bose gas in a separate periodic potential leads to a phononic excitation spectrum that closely mimics those in solid state systems. As a result we show that the impurity-Bose gas system exhibits phonon-induced resonances in the impurity current that were predicted to occur in solids decades ago but never clearly observed. Following this, allowing the bosons to interact strongly, we predict the effect of different strongly-correlated phases of the Bose gas on the motion of the impurity. We show that, by observing the impurity, properties of the excitation spectrum of the Bose gas, e.g., gap and bandwidth, may be inferred along with the filling of the bosonic lattice. In other words the impurity acts as a probe of its environment. To describe the dynamics of such a strongly-correlated system we use the powerful and near-exact time-evolving block decimation (TEBD) method, which we describe in detail. The second part of this thesis then analyses, for the first time, the performance of this method when applied to simulate non-equilibrium classical stochastic processes. We study its efficacy for a well-understood model of transport, the totally-asymmetric exclusion process, and find it to be accurate. Next, motivated by the inefficiency of sampling-based numerical methods for high variance observables we adapt and apply TEBD to simulate a path-dependent observable whose variance increases exponentially with system size. Specifically we calculate the expected value of the exponential of the work done by a varying magnetic field on a one-dimensional Ising model undergoing Glauber dynamics. We confirm using Jarzynski's equality that the TEBD method remains accurate and efficient. Therefore TEBD and related methods complement and challenge the usual Monte Carlo-based simulators of non-equilibrium stochastic processes.

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38

Pittner, Heiko. "The Production and Investigation of Cold Antihydrogen Atoms." Diss., lmu, 2005. http://nbn-resolving.de/urn:nbn:de:bvb:19-36605.

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39

Muldoon, Cecilia. "Control and manipulation of cold atoms in optical tweezers." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:920933c8-441c-4d59-a4f4-87f8c799a820.

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The ability to address and manipulate individual information carriers in a deterministic, coherent, and scalable manner is a central theme in quantum information processing. Neutral atoms trapped by laser light are amongst the most promising candidates for storing and processing information in a quantum computer or simulator, so a scalable and flexible scheme for their control and manipulation is paramount. This thesis demonstrates a fast and versatile method to address and dynamically control the position (the motional degrees of freedom) of neutral atoms trapped in optical tweezers. The tweezers are generated by using the direct image of a Spatial Light Modulator (SLM) which can control and shape a large number of optical dipole-force traps. Trapped atoms adapt to any change in the potential landscape, such that one can re-arrange and randomly access individual sites within atom-trap arrays. A diffraction limited imaging system is used to map the intensity distribution of the SLM onto a cloud of cold atoms captured and cooled using a Magneto Optical Surface Trap (MOST).

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40

Jiang, Kefeng. "Investigation of Stochastic Resonance in Directed Propagation of Cold Atoms." Miami University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=miami1626991662334714.

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41

Sanayei, Ali [Verfasser]. "Cooper pairs and fermion trimers in solids and cold-atom systems / Ali Sanayei." Hamburg : Staats- und Universitätsbibliothek Hamburg Carl von Ossietzky, 2020. http://d-nb.info/1221721097/34.

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42

Kim, Soo Y. "Cold single atoms for cavity QED experiments." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26581.

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Thesis (Ph.D)--Physics, Georgia Institute of Technology, 2009.
Committee Chair: Chapman, Michael; Committee Member: Citrin, David; Committee Member: Kennedy, T. A. Brian; Committee Member: Kuzmich, Alexander; Committee Member: Raman, Chandra. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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43

Huillery, Paul. "Few and Many-body Physics in cold Rydberg gases." Thesis, Paris 11, 2013. http://www.theses.fr/2013PA112040/document.

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Au cours de cette thèse, la physique des systèmes en interaction à été étudié expérimentalement à partir de gaz froids d'atomes de Rydberg. Les atomes de Rydberg sont des atomes dans un état fortement excités et ils ont la propriété d'interagir fortement du fait d'interactions électrostatiques à longue portée. Le premier résultat majeur de cette thèse est l'observation expérimentale d'un processus à quatre corps. Ce processus consiste en l'échange d'énergie interne entre quatre atomes de Rydberg induit par leurs interactions mutuelles. Il a été possible, en plus de son observation expérimentale, de décrire théoriquement ce processus, au niveau quantique. L'excitation par laser des gaz d'atomes de Rydberg en forte interaction a aussi été étudiée durant cette thèse. Cette situation donne lieu à de très intéressants comportements à N-corps. Ce sujet d'intérêt fondamental pourrait aussi amener à d'éventuelles applications pour la réalisation de simulateurs quantiques ou de sources de lumière non classiques. Un second résultat majeur de cette thèse est l'observation expérimentale d'une statistique fortement sub-poissonienne, i.e corrélée de l'excitation Rydberg. Ce résultat confirme le caractère à N-corps de tels systèmes. Le troisième résultat majeur de cette thèse est le développement d'un modèle théorique pour l'excitation par laser des gaz d'atomes de Rydberg en forte interaction. En utilisant les états quantiques dit états collectifs de Dicke, il a été possible de mettre au jour de nouveaux mécanismes liés au comportement à N-corps de ces sytèmes atomiques en forte interaction
Uring this thesis, the Physics of interacting systems has been investigated experimentally using Cold Rydberg gases. Rydberg atoms are highly excited atoms and have the property to interact together through long-range electrostatic interactions.The first highlight of this thesis is the direct experimental observation of a 4-body process. This process consists in the exchange of internal energy between 4 Rydbergs atoms due to their mutual interactions. In addition to its observation, it has been possible to describ this process theoretically at a quantum level.The laser excitation of strongly interacting Rydberg gases has been also investigated during this thesis. In this regime, the interactions between Rydberg atoms give rise to very interesting many-body behaviors. In addition to fundamental interest, such systems could be used to realyze quantum simulators or non-classical light sources.A second highlight of this thesis is the experimental observation of a highly sub-poissonian, i.e correlated, excitation statistics. This result confirms the many-body character of the investigated system.The third highlight of this thesis is the development of a theoretical model to describ the laser excitation of strongly interacting Rydberg gases. Using the so-called Dicke collective states it has been possible to point out new mechanismes related to the many-body character of strongly atomic interacting systems

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44

Hattermann, Helge [Verfasser], and József [Akademischer Betreuer] Fortágh. "Interfacing cold atoms and superconductors / Helge Hattermann ; Betreuer: József Fortágh." Tübingen : Universitätsbibliothek Tübingen, 2013. http://d-nb.info/1162844671/34.

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45

Langmack, Christian Bishop. "Universal Loss Processes in Bosonic Atoms with Positive Scattering Lengths." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1385483878.

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46

Dilyard, Ian Thomas. "Bidirectional and Unidirectional Ratcheting of Cold Atoms in a Dissipative 3D Optical Lattice." Miami University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=miami1627007454969735.

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47

Gill, Christopher. "Simulating transport through quantum networks in the presence of classical noise using cold atoms." Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7302/.

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In work towards the development and creation of practical quantum devices for use in quantum computing and simulation, the importance of long lived coherence is key to the advantages offered over classical systems. Isolation from environmental sources of decoherence is of integral importance to such platforms. Recent experiments of biological systems seem to indicate the existence of certain structures that utilise the decohering effects of their surrounding environments to enhance performance. In this thesis, we present a novel experimental set-up used to simulate the effect of decoherence-enhanced systems by mapping the energy level structure of laser cooled Rubidium 87 atoms interacting with electromagnetic fields to a quantum network of connected sites. Classical noise is controllably added to the states to create a tunable system to explore these effects. We present the design and implementation of the system, with results of several technical aspects, along with initial work on the effect of the applied noise on transport through the network. We present a key result that transport through the network is non-trivially enhanced by the presence of an optimum amplitude of noise, pointing to the interplay between the coherent nature of the quantum system and the decoherence provided by the noise.

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48

Li, Tao. "Manipulation of cold atoms using an optical one-way barrier." Thesis, Connect to title online (Scholars' Bank) Connect to title online (ProQuest), 2008. http://hdl.handle.net/1794/8589.

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Анотація:

Thesis (Ph. D.)--University of Oregon, 2008.
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 114-119). Also available online in Scholars' Bank; and in ProQuest, free to University of Oregon users.

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49

Forbes, Michael McNeil. "Fermionic superfluids : from cold atoms to high density QCD : gapless (breached pair) superfluidity and kaon condensation." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/32299.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2005.
Includes bibliographical references (p. 189-198).
In this thesis, we explore aspects of fermionic superfluidity through a mean-field approximation. Our framework is extremely general, includes both pairing and Hartree-Fock contributions, and is derived rigorously from a variational principle. This framework allows us to analyze a wide range of fermionic systems. In this thesis, we shall consider two-species nonrelativistic atomic systems with various types of interactions, and relativistic QCD systems with 3 x 3 x 4 = 36 different quark degrees of freedom (3 colours, 3 flavours, and 4 relativistic degrees of freedom). We discuss properties of a new state of matter: gapless (Breached Pair) superfluidity, and include a summary of potential experimental realizations. We also present numerical results for a completely self-consistent approximation to the NJL model of high-density QCD and use these results to demonstrate a microscopic realization of kaon condensation. We describe how to match the mean-field approximation to the low-energy chiral effective theory of pseudo-Goldstone bosons, and we extract the numerical coefficients of the lowest order effective potential.
by Michael McNeil Forbes.
Ph.D.

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50

Bonneau, Marie. "Mélange à quatre ondes atomique dans un réseau optique." Phd thesis, Université Paris Sud - Paris XI, 2011. http://tel.archives-ouvertes.fr/tel-00665955.

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Ce mémoire de thèse décrit une expérience de création de paires d'atomes jumeaux par mélange à quatre ondes en présence d'un réseau optique. Ces atomes jumeaux sont analogues aux photons jumeaux obtenus par conversion paramétrique, lesquels ont été employés dans plusieurs expériences fondamentales d'optique quantique, ainsi que pour des applications en interférométrie et en information quantique. En raison de la relation de dispersion, l'accord de phase peut être obtenu quand les atomes se déplacent dans le réseau optique. Le mélange à quatre ondes qui se produit alors spontanément constitue un cas particulier d'instabilité dynamique. Nous avons réalisé cette expérience à partir d'un gaz dégénéré d'hélium métastable, obtenu dans un piège optique très allongé. On a superposé aux atomes un réseau optique en mouvement, qui est également décrit dans ce mémoire. Au moyen d'un détecteur d'atomes uniques résolu à trois dimensions, nous avons caractérisé le mélange à quatre ondes obtenu. Nous avons étudié les conditions d'accord de phase de ce processus, et les différents modes peuplés, montrant que la méthode que nous employons permet de diffuser préférentiellement les atomes dans deux fines classes de vitesse, que l'on peut ajuster et dont on contrôle les populations. Cette flexibilité facilitera l'utilisation des paires d'atomes pour des expériences futures. Au niveau de chacune de ces deux classes de vitesses, nous avons mesuré une corrélation de type Hanbury Brown et Twiss. Par ailleurs, nous avons démontré une réduction des fluctuations de la différence de population entre les deux classes sous le bruit de grenaille. La coexistence de ces deux effets témoigne du caractère non-classique des paires générées, qui pourront être exploitées pour des expériences d'optique atomique quantique, comme par exemple pour observer l'effet Hong-Ou-Mandel sur des atomes.

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