This thesis describes the design, construction and optimisation of a new apparatus to produce Bose-Einstein condensates (BECs) of 87Rb atoms. The main aim in building this system was to include a high resolution imaging system capable of resolving single atoms. Optical access for the imaging system was created by including a stage of atom transport in which the atoms are magnetically transferred ~50 cm from a magneto-optical trap (MOT), where they are initially collected, to a glass science cell where experiments are carried out and imaging takes place. Two magnetic transport schemes have been demonstrated, based on approaches first used in other laboratories. First, a scheme in which the atoms are transferred in a moving pair of magnetic trapping coils. Second, a hybrid scheme where the atoms are translated part of the distance in the moving coils, and the rest of the way by switching the current in a chain of fixed coils. This second scheme was designed to allow optical access for a high numerical aperture microscope objective to be placed immediately next to the science cell for high resolution imaging. The atoms were first collected in a large pyramid MOT which can be loaded with 3 × 10^9 atoms in a time of 20 s. Around half of these atoms – those in the |F = 1, mF = −1> magnetic substate – were then magnetically trapped prior to transport. The typical fraction of the trapped atoms transferred to the science cell was ~30% and ~18% for the moving coils and hybrid schemes respectively. Evaporative cooling was carried out on the atom cloud following transport with the moving coils and loading into a time-orbiting potential trap. The optimised cooling sequence lasted for 28 s and consistently produced a pure condensate with 5 × 10^5 atoms. A BEC has also been produced by evaporative cooling following hybrid transport. The next experimental steps will be to optimise the hybrid transfer approach further and install the high resolution imaging system. The system is well-placed to continue an ongoing series of experiments in which ultracold atoms are trapped in RF-dressed potentials. These potentials will be used to study low-dimensional quantum gases as well as in experiments where small atom number BECs are rapidly rotated to enter the fractional quantum Hall regime.

This study will focus on confined, negative space, the claustrum, in its varied manifestations, and on ascents and descents within both the cities themselves and the specific buildings which house these claustra. By definition, the claustrum signifies psychological and often physical confinement. In both films, the major characters are restricted by claustra which simultaneously reflect their psychological conditions or stages of development and also confine them physically. Both Roeg and De Palma are keenly aware of how to manipulate the spectator’s own fears of claustra and exploit them to the full in all of their films. This analysis deals with the aesthetics of space interpreted towards psychological ends: the malevolent space of the claustrophobic nightmare, rather than the positive space of the felicias dream. One model of positive psychological space can be found in Gaston Bachelard’s The Poetics of Space (1964). His essential comments on enclosed spaces - especially on the diametric opposition of garret and cellar - and his insights into the nature of the city and its influence on its inhabitants are briefly examined and then inverted to provide a starting point for this study.

This body of work operates at the border between fashion and performance, with the intention to explore the performativity of body, inrelation to forms of dress. The work presented in this thesis sets out to examine the ways the performed act of making may inform theoutcome through designing new activities of getting dressed as producers for dress, while questioning the static systems of makingdress that develops form mainly with an approximation of a bodily form.The work is not about dance, it is not about theatre, it is not about choreography. This work is about the activity of getting dressed andwhat potential knowledge in dress that may be extracted from simply shifting the established order of the relationship between bodyand dress. However, from a methodological point of view, the work is developed through choreography and performance in relation toarranged space as tools to design the activities, and these may well be viewed as a danced or theatrical and dramaturgical play of body,motion, material and dress.These aspects are part of the outcome that suggests not only new formal relationships between body and dress and new methods formaking dress, but also new ways of looking at, and consuming the art of dress.

No description available.

Time-varying fields are widely used to extend the accessible range of trapping potentials for ultracold atoms. This work explores two very different examples of such fields, in the radiofrequency and optical regimes, whose interactions with trapped atoms can both be described in terms of the dressed atom picture. Forming the basis of this work are radiofrequency dressed adiabatic potentials based on macroscopic trapping coils. Atoms are confined at the south pole of the resultant oblate spheroidal trapping surfaces. This work describes the extension of these potentials by two different methods: the application of multiple dressing radiofrequencies, and addition of a rapidly-scanned optical dipole trap. This is the first experimental demonstration of a multiple-radiofrequency dressed adiabatic potential, explored using ultracold ⁸⁷Rb atoms confined in a highly configurable double well. Due to the independent generation of each constituent dressing frequency, the depth of each trapping well and the height of the barrier are easily manipulated, enabling precise and reliable transfer of atoms between the available trapping geometries. Experimental work includes an exploration of the potential-shaping capabilities of the three-radiofrequency system, and characterisation of the potential landscape using radiofrequency spectroscopy with good agreement to the eigenvalues numerically calculated using Floquet theory. This initial exploration of multiple-radiofrequency techniques lays the groundwork for applications in studying double well physics in a two-dimensional system, and independent state or species selective manipulation of trapped atoms. The potential shaping capabilities of this method can also be extended by applying additional trapping frequencies. In a supplementary line of experimental work, an optical dipole trapping system has been constructed, and the trapping beam aligned to the lower surface of the radiofrequency dressed trapping shell in order to sculpt the radial confinement. Beam shaping is achieved using an acousto-optic deflector, which can be used to produce either a composite array of static deflected beams, a rapidly-scanned painted potential, or some combination of the two approaches. The development and extension of the experimental apparatus required to implement these enhanced dressed state potentials is explored, and the challenges of their experimental implementation considered.

The performance of electrical and optical devices based on two-dimensional semiconductors (2D) such as molybdenum disulfide is critically influenced due to very poor light absorption in the atomically thin layers. In this study, the phonon mediated optical absorption and emission properties in single atomic layers of MoS2 have been investigated. The electronic transitions in MoS2 due to near-field optical interaction and the influence of interface phonons due to the dielectric substrate GaN on the relaxation of optically generated carriers will be described. The near-field interaction can be induced in the presence of metal plasmons deposited on the surface of MoS2 monolayers. A hybrid metal-semiconductor system was realized by the deposition of silver (Ag) NPs on MoS2 layer and the localized plasmon modes were selectively chosen to interact with quasiparticles such as excitons and phonons. These quasiparticles are confined within the single atomic layer of MoS2 and are stable at room temperatures due to high binding energy. The lattice vibrational modes in MoS2 can be optically excited with the pulses from a femtosecond laser. These phonon modes can be optically dressed due to near-field interaction in the hybrid Ag-MoS2 system under an optical excitation resonant to localized plasmon modes. The coherent dynamics of the carriers in MoS2 were manipulated by the generation of dressed phonons. The driving field creates a coherence between the ground levels in the presence of optical near-field. A strong coupling between the exciton and plasmon modes forming a plexciton band is observed at room temperature within the coherence lifetime of the system. A significant enhancement of photoluminescent (PL) emission from MoS2 monolayer occurs due to carrier density modulation in the presence near-field interactions. The absorption and emission properties of MoS2 are influenced due to the interactions with the semiconducting substrate. The coupling of carriers in MoS2 with the interfacial phonons, and the charge and energy transfer across the interface in 2D MoS2-GaN (0001) significantly change the UF absorption properties and the relaxation of carriers from the excitonic absorption states. An increased light absorption and enhanced PL emission from the single atomic layer of MoS2 was observed. The phonon-assisted processes can activate the dipole forbidden transitions and hence can explain the interaction of incident light in single atomic layer of MoS2. The MoS2-GaN heterostructure provides a platform to exploit strong coupling between the free carriers or excitons, plasmons and phonons. The gold (Au) NPs have a plasmon energy resonant to MoS2 and hence results in the strong exciton-plasmon coupling due to near-field interaction. In the meantime, the localized plasmon energy of platinum (Pt) NPs is selected to be in resonance to GaN bandedge emission and resonant to C excitonic state in MoS2. The localized plasmons in Pt can actively interact with carriers in MoS2 near Γ-point. The non-equilibrium absorption characteristics of MoS2 nanosheets on GaN hybridized with Au and Pt NPs are influenced due to activation of the defect levels of GaN induced due to interband optical excitation.

Nous étudions différents aspects liés aux compactifications hétérotiques avec torsion. Nous définissons et calculons le genre elliptique vêtu associé aux compactifications Fu-Yau, et exploitons ce résultat pour calculer les corrections de seuil à une boucle de différents couplages BPS-saturés dans l’action effective de supergravité à quatre dimen- sions. Enfin nous nous intéressons à des solutions supersymétriques non-compactes qui généralisent, entre autres, les solutions hétérotiques connues sur le conifold. / We study various aspects of heterotic compactifications with torsion. We de- fine and compute the dressed elliptic genus associated to Fu-Yau compactifications, and use this result to compute one-loop threshold corrections to various BPS-saturated cou- plings in the four-dimensional effective supergravity action. Finally, we study non-compact supersymmetric solutions which generalize, among others, the known heterotic solutions on the conifold.

Infrared divergences arising in theories with massless gauge bosons have been shown to cancel in scattering amplitudes when using dressed states constructed from the Faddeev- Kulish approach to the asymptotic states. It has been established that these states are closely related to asymptotic symmetries of the theory, that is, non-vanishing gauge trans- formations at the asymptotic boundary. In this thesis, we review both of these aspects for QED and non-Abelian gauge theories. We also investigate the expectation value of the non-Abelian field strength tensor using dressed states. We then present a novel con- struction of the dressing operator for non-Abelian gauge theories using Wilson lines. We demonstrate, to order O(g2), that each term of the dressing operator is reproduced in the presented Wilson line approach, along with additional terms that warrant a more thorough understanding. This work extends previous results that pertained to QED and gravity.

Free-ranging population of sika deer, roe deer and wild board in micro-region "Konstantinolázeňsko" in Czech Republic, has been determining dressed body weight, whole body weight, weight of head, weight of limb and weight of internal organs (heart, lungs, liver, spleen and kidneys). The correlation between all weights was calculated. During the research was determined mean weight between whole body and dressed body. In this study the dressed mean weight of sika deer was 74,03 % of the whole mean weight. For wild board the mean dressed weight was about 78,56% of the whole weight and for roe deer mean it was about 76,66% of the whole weight. Obtain weight has been statistically analyzing of ages, sexuality, seasonal variation. For both sexuality of wild board was statically proven that body weight is increasing with age. For sika deer calfs was statically proven that body weight was higher if the calf was shoot after 15. 1. then cals was shoot before. For sika deer with out age difference was statically proven that sika males had higher body weight than sika females. Other types of statistics are listed in the document.

L'exploration du monde quantique au moyen d'objets macroscopiques constitue l'un des défis centraux de ces dernières décennies pour la recherche en physique. Parmi les systèmes proposés pour atteindre cet objectif, les systèmes hybrides, qui couplent un résonateur nanomécanique à un qubit unique, font figure de paradigme.L'excitation cohérente d'un oscillateur mécanique macroscopique par un unique spin électronique ouvrirait en particulier de nouvelles perspectives pour la création d'états quantiques arbitraires du mouvement.Dans ce manuscrit, nous considérons un système hybride constitué d'un oscillateur nanomécanique et du spin électronique d'un unique centre NV, couplés entre eux par une interaction magnétique. Nous nous concentrons sur le cas d'une interaction paramétrique où la vibration mécanique module l'énergie du qubit, et plus précisément sur le cas où le qubit ainsi forcé et l'oscillateur mécanique évoluent sur des échelles de temps comparables.Dans cette situation, nos observations montrent une synchronisation de la dynamique du qubit sur l'oscillation mécanique. Le phénomène est dans un premier temps abordé par une expérience-test qui remplace le mouvement mécanique par un champ radiofréquence en couplage paramétrique avec le spin. Cette première implémentation permet de dégager les propriétés essentielles de l'effet paramétrique, qui est dans un second temps observé sur l'expérience principale.Dans cette seconde expérience, un centre NV est attaché à l'extrémité d'un nanofil de carbure de silicium en vibration placé dans un fort gradient de champ magnétique. Le caractère bidimensionnel des déformations du nanofil octroie alors à la synchronisation des signatures vectorielles encore inédites, qui peuvent aussi être interprétées comme la manifestation d'un triplet de Mollow phononique, ainsi qu'il a été observé dans les premières expériences d'électrodynamique quantique.Finalement, nous explorons la robustesse de la synchronisation vis-à-vis du mouvement Brownien du résonateur, et démontrons la possibilité de protéger le qubit de cette source de décohérence additionnelle grâce à une excitation mécanique de faible amplitude. / Probing the quantum world with macroscopic objects has been a core challenge for research in physics during the past decades. Proposed systems to reach this goal include hybrid devices that couple a nanomechanical resonator to a single spin qubit. In particular, the coherent actuation of a macroscopic mechanical oscillator by a single electronic spin would open perspectives in the creation of arbitrary quantum states of motion.In this manuscript, we investigate a hybrid system coupling a nanomechanical oscillator and a single electronic spin of a NV defect in magnetic interaction. We focus on the parametric interaction case, when the mechanical motion modulates the qubit energy, and in particular when the driven qubit and mechanical oscillators evolves on similar timescales. In that situation a synchronization of the qubit dynamics onto the mechanical motion is observed. The phenomenon is first explored on a test experiment where mechanical motion is replaced by a parametrically coupled RF field. It allows to establish the main properties of the phenomenon, which is subsequently investigated on the core experiment. It consists of a NV defect attached at the vibrating extremity of a silicon carbide nanowire, immersed in a strong magnetic field gradient. The bidimensional character of the nanowire deformations is responsible for novel vectorial signatures in the synchronization, which can also be viewed as a phononic Mollow triplet as observed in early quantum electrodynamics experiments. We finally explore the robustness of the synchronization against the Brownian motion of the resonator and demonstrate the possibility to protect the qubit against this additional decoherence source by applying a small coherent mechanical drive.