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We studied bosonic quantum gases trapped in an optical lattice coupled to Rydberg states. The associated model is described a two-component system consisting of atoms in the electronic ground state and in the Rydberg state. The model also includes a coupling term between the two components and the van der Waals interaction between the Rydberg atoms. To gain as much insight into this model as possible, we determined the many-body ground states for both isotropic and anisotropic van-der-Waals interactions. The calculations are performed for square optical lattices as well as for triangular optical lattices. Regardless of the geometry of the long-range interaction and the optical lattice, we found phase diagrams consisting of DW, SF and SS phases, with their parameter ranges depending on the geometries. The crystalline structures appearing in the DW and SS phases exhibited a wide variety of interatomic distances between Rydberg atoms. We found that anisotropic interaction leads to striped density modulations, which is particularly beneficial for the coexistence of crystalline structure and finite condensation. The difference between a square and a triangular optical lattice was only relevant for parameters through which the system exhibited dense density modulation and whose length scale is comparable to the lattice constant. For parameters however, through which phases consisting of Rydberg atoms with large interatomic distances appeared, the difference between the lattice geometries is hardly noticeable in the phase diagram. Since these results are promising for experimental realization, we completed the study by quantifying the influence of dissipation and decoherence, which arose from the spontaneous emission and blackbody radiation present for excited states. It was suspected that the finite lifetime of the Rydberg states and dephasing processes are so detrimental to the characteristic properties of SS phases, which would render SS phase of Rydberg-dressed quantum gases experimentally undetectable. Using the Lindblad master equation, we checked the strength of dissipation and decoherence in the context of time evolutions. We took as initial states both a DW and a SS phase obtained in the scope of the previous calculations and let these states evolve in time in the presence of the two mentioned processes. We found that indeed dissipation and decoherence increase with increasing rates of spontaneous emission and dephasing. Moreover, we observed that the SS phase benefits from the associated finite hopping amplitude, since redistribution of atoms in the system allowed the system to be less affected by dissipation and decoherence. The long-lived state after reorganization of the atoms possessed a finite condensate decreasing with time, but for typical lifetimes and dephasing rates, this condensate did not disappear completely within the time ranges considered, which is promising for the experimental observation of such phases. We therefore conclude that bosonic quantum gases trapped in optical lattices and coupled to Rydberg states is a promising candidate for the realization of SS phases.However, since collective phenomena and other experimental hurdles, such as the maximum realizable tunnel amplitude and coupling strength, could potentially pose difficulties, we proposed another system, through which SS phases could be realized. In contrast to the previous Rydberg-dressed bosonic quantum gas, the atoms in the electronic ground state are now weakly coupled pairwise to macrodimer states. As a result, the atoms in the ground state acquire an effective long-range interaction, however only if the distance between the two atoms matches the molecular bond length. We presented the single-color and two-color coupling schemes associated to the macrodimer dressing and discussed their differences with regards to the effective dressed interaction, the total AC Stark shift of the coupling lasers and the lifetime of such macrodimer states. For the calculation of the dressed interaction we computed three potential landscapes of two chemical elements and determined the coupling strength to the macrodimer states emerging from the avoided crossings in these potentials. We found that the coupling strength generally increases with larger principal quantum number or higher trapping frequencies. For trapping frequencies relevant in systems with finite hopping amplitude the coupling strength did not reach its optimal value, however the resulting dressed interaction becomes comparable to the values typically used for the on-site interaction and hopping amplitude. Furthermore we discovered that the magnitude of the dressed interaction did not depend on the type of coupling scheme, while the total AC Stark shift can be tuned out for a two-color coupling scheme. The vanishing differential light shift would then allow for coherent hopping processes. We calculated and shown that the dressing quality, i.e. the ratio between dressed interaction and decoherence, obtained through the macrodimer dressing is significantly larger than the dressing quality associated with the usual Rydberg dressing. Due to these promising aspects of the proposed system, we studied the phase diagram of the corresponding extended Bose-Hubbard model. Since the distance-dependency of the interaction can be changed based on the selection of the addressed macrodimer state, we compared the phase diagram for both NN as well as NNN interaction. Within the range of the determined dressed interaction strengths, the phase diagrams consisted DW, SF and SS regimes. We found that NNN interactions lead to striped crystalline structures, which is advantageous for SS phases. We furthermore varied the average filling of the lattice and investigate the necessary dressed interaction strengths. Interestingly we computed a lower necessary dressed interaction for lower fillings in the regime of small hopping amplitudes, while larger amplitudes profit from a higher filling. Since these results were particularly promising, we concluded the section with a proposal on how SS phases can be adiabatically prepared in macrodimer-dressed systems. To this end we simulated the slow ramp up of the coupling to the macrodimer states, while including the finite lifetime of these states throughout the time evolution. We determined critical dressed interaction above which an initial SF phase exhibits spontaneously broken lattice translational symmetry. Since the admixture of the macrodimer state in the system decreases with time due to their finite lifetime, we discovered that longer ramping times require a larger dressed interaction. However even for long ramping times the necessary dressed interaction was well within the range of calculated dressed interactions and we are thus confident, that macrodimer-dressed systems could lead to the experimental realization and observation of SS phases.On a personal note, as these results have been in the making for a while it was interesting to experience the ups and downs along the years as new insight about Rydberg ensembles continuously emerged. On one hand the phase diagrams of Rydberg-dressed gases displayed in the first part of Chapter 4 received ambiguous reactions as the concept behind such systems seemed simple yet promising, however limiting phenomena such as differential light shifts of the coupling laser impeding coherent hopping or lifetime inhibiting avalanche dephasing processes were only recently observed at that time and not fully understood yet. On the other hand through advances in technology and engineering of innovative methods tremendous insight about these obstacles was gained, which even allowed to overcome some of the previously limiting factors. A few years ago for example it thus became possible to realize a Rydberg-dressed fermionic quantum gas, in which dynamics given by the interplay of hopping and long-range interaction were experimentally observed [268]. Due to the amount of effort invested in the field of Rydberg ensembles, we are thus hopeful that in the future SS phases will be experimentally observed in trapped Rydberg-dressed and macrodimer-dressed quantum bosonic systems.

A well-studied scenario in quantum parameter estimation theory arises when the parameter to be estimated is imprinted on the initial state by a Hamiltonian of the form \\(\\theta G\\). For such \"phase shift Hamiltonians\" it has been shown that one cannot improve the channel quantum Fisher information by adding ancillas and letting the system interact with them. Here we investigate the general case, where the Hamiltonian is not necessarily a phase shift, and show that in this case in general it \\emph{is} possible to increase the quantum channel information and to reach an upper bound. This can be done by adding a term proportional to the derivative of the Hamiltonian, or by subtracting a term to the original Hamiltonian. Both methods do not make use of any ancillas and show therefore that for quantum channel estimation with arbitrary parameter-dependent Hamiltonian, entanglement with an ancillary system is not necessary to reach the best possible sensitivity. By adding an operator to the Hamiltonian we can also modify the time scaling of the channel quantum Fisher information. We illustrate our techniques with NV-center magnetometry and the estimation of the direction of a magnetic field in a given plane using a single spin-1 as probe.

We consider quantum channel-estimation for depolarizing channels and phase-flip channels extended by ancilla qubits and fed with a GHZ or W state. After application of the channel one or several qubits can be lost, and we calculate the impact of the loss on the quantum Fisher information that determines the smallest uncertainty with which the parameters of these channels can be estimated.

Distributed-work has introduced challenges for both employees and managers alike. Maintaining a form of supervision and discipline remains then necessary as control is the ultimate means for the hierarchy to bridge the issue of distance. With regard to the unprecedented changes generated by the significant development of ICTs in organizations, we expressed the necessity to analyze how control is reconsidered within the managerial breakdown introduced by distributed-work. Our theoretical reasoning finally led us to use the works of French philosopher Gilles Deleuze as a basis for a more relevant conceptual framework. Data coming from 49 interviews and 7 days as non-participant observer enabled us to provide evidences for the disruption of management practices due to the reconsideration of control in distributed-work. Both for managers, evolving from a supervisory to a facilitator status, and distributed-workers themselves, whose activities will mainly be directed by the management of their visibility, responsiveness and modulation. Ultimately, this PhD dissertation provides concrete managerial manifestations for Deleuzian societies of control.

Julien MATHIEU Un mythe fondateur de la musique contemporaine: le «scandale» provoqué par la création de Désertsd’Edgar Varèse, le 2 décembre 1954 Le deux décembre 1954 à Paris, au Théâtre des Champs-Élysées, était créée, dans le cadre de la programmation musicale de la R.T.F., une œuvre d’un compositeur alors très peu connu en France,Déserts d’Edgar Varèse.Le compositeur y développait une esthétique marquée par la volonté d’inté~grer à la musique occidentale des sons jus~qu’alors refoulés (percussions,bruits d’usines, etc...). Or, la présence de tels sons dans un cadre très institutionnalisé et codifié, provo~qua des réactions violentes de la part du public présent. À partir de sources variées, issues notamment des fonds de la R.T.F. (archives écrites,fonds sonores et télévisuels), on cherchera à mieux saisir ce scandale, en privilégiant une approche micro-historique nous permettant d’analyser les raisons qui poussèrent certains à faire comprendre au compositeur que sa musique, par son carac~tère d’étrangeté, n’était pas «à sa place». Ceci nous permettra d’éclairer la postérité du scan~dale qui, si elle fut peu importante dans l’opi~nion, fut plus déterminante pour les compositeurs contemporains, qui firent de l’événement une sorte de «bataille héroïque» de la création artistique moderne, instrumen~talisant ainsi la transgression, érigée en norme. On December the 2nd 1954, in the thea~ter of the Champs-Élysées, a masterpiece entitled Déserts, composed by Edgar Varèse, who was unknown in France at that time, was created in the framework of the musical pro~gramming of the R.T.F.. Edgar Varèse deve~lopped in Désertsan aesthetic marked by the will of integrating into western music sounds that were unused before (percussion, noises from factories and so on...). However the use of such sounds in a very institutionalized and codified framework provoked violent reac~tions from the audience that was present. Referring to various resources from the R.T.F. (written,sonorous and television archives),we will try to understand that scandal better by priviledging a micro-historical approach.This will help us to analyse the reasons why some persons made the composer understand that his music was out of place because of its strangeness.All this will lead us to explain the importance of the scandal even if it did not remain in people’s mind. However it was determining for the contemporary composers who celebrated the event as a kind of heroic battle concerning modern artistic creation. Thus transgression was magnified and became a standard.

Le deux décembre 1954 à Paris, au Théâtre des Champs-Élysées, était créée, dans le cadre de la programmation musicale de la R.T.F., une œuvre d'un compositeur alors très peu connu en France, \"Déserts\" d'Edgar Varèse. Le compositeur y développait une esthétique marquée par la volonté d'intégrer à la musique occidentale des sons jusqu'alors refoulés (percussions, bruits d'usines, etc...). Or, la présence de tels sons dans un cadre très institutionnalisé et codifié, provoqua des réactions violentes de la part du public présent. À partir de sources variées, issues notamment des fonds de la R.T.F. (archives écrites, fonds sonores et télévisuels), on cherchera à mieux saisir ce scandale, en privilégiant une approche micro-historique nous permettant d'analyser les raisons qui poussèrent certains à faire comprendre au compositeur que sa musique, par son caractère d'étrangeté, n'était pas \"à sa place\". Ceci nous permettra d'éclairer la postérité du scandale qui, si elle fut peu importante dans l'opinion, fut plus déterminante pour les compositeurs contemporains, qui firent de l'événement une sorte de \"bataille héroïque\" de la création artistique moderne, instrumentalisant ainsi la transgression, érigée en norme. /// On December the 2nd 1954, in the theater of the Champs-Élysées, a masterpiece entitled \"Déserts\", composed by Edgar Varèse, who was unknown in France at that time, was created in the framework of the musical programming of the R.T.F.. Edgar Varèse developped in \"Déserts\" an aesthetic marked by the will of integrating into western music sounds that were unused before (percussion, noises from factories and so on...). However the use of such sounds in a very institutionalized and codified framework provoked violent reactions from the audience that was present. Referring to various resources from the R.T.F. (written, sonorous and television archives), we will try to understand that scandal better by priviledging a micro-historical approach. This will help us to analyse the reasons why some persons made the composer understand that his music was out of place because of its strangeness. All this will lead us to explain the importance of the scandal even if it did not remain in people's mind. However it was determining for the contemporary composers who celebrated the event as a kind of heroic battle concerning modern artistic creation. Thus transgression was magnified and became a standard.

ABSTRACT IN FRENCH: Le deux décembre 1954 à Paris, au Théâtre des Champs-Élysées, était créée, dans le cadre de la programmation musicale de la R.T.F., une oeuvre d'un compositeur alors très peu connu en France, Déserts d'Edgar Varèse. Le compositeur y développait une esthétique marquée par la volonté d'intégrer à la musique occidentale des sons jusqu'alors refoulés (percussions, bruits d'usines, etc...). Or, la présence de tels sons dans un cadre très institutionnalisé et codifié, provoqua des réactions violentes de la part du public présent. À partir de sources variées, issues notamment des fonds de la R.T.F. (archives écrites, fonds sonores et télévisuels), on cherchera à mieux saisir ce scandale, en privilégiant une approche micro-historique nous permettant d'analyser les raisons qui poussèrent certains à faire comprendre au compositeur que sa musique, par son caractère d'étrangeté, n'était pas « à sa place ». Ceci nous permettra d'éclairer la postérité du scandale qui, si elle fut peu importante dans l'opinion, fut plus déterminante pour les compositeurs contemporains, qui firent de l'événement une sorte de « bataille héroïque » de la création artistique moderne, instrumentalisant ainsi la transgression, érigée en norme. // ABSTRACT IN ENGLISH: On December the 2nd 1954, in the theater of the Champs-Élysées, a masterpiece entitled Déserts, composed by Edgar Varèse, who was unknown in France at that time, was created in the framework of the musical programming of the R.T.F.. Edgar Varèse developped in Déserts an aesthetic marked by the will of integrating into western music sounds that were unused before (percussion, noises from factories and so on...). However the use of such sounds in a very institutionalized and codified framework provoked violent reactions from the audience that was present. Referring to various resources from the R.T.F. (written, sonorous and television archives), we will try to understand that scandal better by priviledging a micro-historical approach. This will help us to analyse the reasons why some persons made the composer understand that his music was out of place because of its strangeness. All this will lead us to explain the importance of the scandal even if it did not remain in people's mind. However it was determining for the contemporary composers who celebrated the event as a kind of heroic battle concerning modern artistic creation. Thus transgression was magnified and became a standard. Reprinted by permission of Société d'histoire moderne et contemporaine