L'expérience esthétique de l'environnement : une tension sociopolitique entre l'ordinaire et l'extraordinaire ?

Concernant la dimension esthétique des relations des hommes à leur environnement, deux lectures dominent la littérature scientifique : d'un côté, une esthétique qui serait l'apanage d'un regard distancié, associée à l'idée d' « extraordinaire » ; de l'autre côté, une esthétique qui, à force de puiser dans l'ordinaire, finirait par s'y dissoudre au profit d'autres valeurs dominantes utilitaires. À partir d'une analyse d'expériences de villégiature dans des contextes très différents, nous exposons que la dimension esthétique des relations des hommes à leur environnement peut être appréhendée comme une manifestation de la mise en tension entre ordinaire et extraordinaire. Une telle position permet de prendre toute la mesure de la dimension politique de l'esthétique, que l'expérience esthétique se fonde sur l'exclusion « d'autres » ou qu'elle se nourrisse « d'autres » et des liens sociaux qui les unissent. / When we consider aesthetics in human relationships with the physical environment as addressed in scientific literature, two leading approaches emerge. On the one hand aesthetics would appear to be the prerogative of a distanciated look and linked to the notion of extraordinary. On the other, aesthetics would be so immersed in "ordinary life" that if finally dissolves in it and vanishes behind other leading values, such as utilitarian ones. That is particularly obvious in studies of local people's aesthetical experiences. In this paper, we argue that there could be a third way between these two approaches to understanding the aesthetical dimension of human relationships with the environment. We analysed semi-directive interviews with people in two contrasted situations: mountain hikers in the Pyrénées and holiday-makers in the Sensée marshes of northern France. We point out that aesthetics in people's relationships with their physical environment may be seen as manifesting the tension between ordinary and extraordinary. This enables us to perceive the importance of the political dimension of aesthetics, whether visible (experience of a place explicitly incorporates the social relationships that take place in it), or concealed behind an aesthetical experience that appears to be very direct, material and autonomous

Towards achieving strong coupling in 3D-cavity with solid state spin resonance

We investigate the microwave magnetic field confinement in several microwave 3D-cavities, using 3D finite-element analysis to determine the best design and achieve strong coupling between microwave resonant cavity photons and solid state spins. Specifically, we design cavities for achieving strong coupling of electromagnetic modes with an ensemble of nitrogen vacancy (NV) defects in diamond. We report here a novel and practical cavity design with a magnetic filling factor of up to 4 times (2 times higher collective coupling) than previously achieved using 1D superconducting cavities with small mode volume. In addition, we show that by using a double-split resonator cavity, it is possible to achieve up to 200 times better cooperative factor than the currently demonstrated with NV in diamond. These designs open up further opportunities for studying strong and ultra-strong coupling effects on spins in solids using alternative systems with a wider range of design parameters.Comment: 20 pages, 9 figure

Non-intrusive tunable resonant microwave cavity for optical detected magnetic resonance of NV centres in nanodiamonds

Optically detected magnetic resonance (ODMR) in nanodiamond nitrogen-vacancy (NV) centres is usually achieved by applying a microwave field delivered by micron-size wires, strips or antennas directly positioned in very close proximity (∼ μm) of the nanodiamond crystals. The microwave field couples evanescently with the ground state spin transition of the NV centre (2.87 GHz at zero magnetic field), which results in a reduction of the centre photoluminescence. We propose an alternative approach based on the construction of a dielectric resonator. We show that such a resonator allows for the efficient detection of NV spins in nanodiamonds without the constraints associated to the laborious positioning of the microwave antenna next to the nanodiamonds, providing therefore improved flexibility. The resonator is based on a tunable Transverse Electric Mode in a dielectric-loaded cavity, and we demonstrate that the resonator can detect single NV centre spins in nanodiamonds using less microwave power than alternative techniques in a non-intrusive manner. This method can achieve higher precision measurement of ODMR of paramagnetic defects spin transition in the micro to millimetre-wave frequency domain. Our approach would permit the tracking of NV centres in biological solutions rather than simply on the surface, which is desirable in light of the recently proposed applications of using nanodiamonds containing NV centres for spin labelling in biological systems with single spin and single particle resolution. © 2013 Copyright SPIE

Addressing a single NV−^{-} spin with a macroscopic dielectric microwave cavity

We present a technique for addressing single NV$^{-}$ center spins in diamond over macroscopic distances using a tunable dielectric microwave cavity. We demonstrate optically detected magnetic resonance (ODMR) for a single NV$^{-}$ center in a nanodiamond (ND) located directly under the macroscopic microwave cavity. By moving the cavity relative to the ND, we record the ODMR signal as a function of position, mapping out the distribution of the cavity magnetic field along one axis. In addition, we argue that our system could be used to determine the orientation of the NV$^{-}$ major axis in a straightforward manner

Novel schemes for optical signal generation using laser injection locking with application to Brillouin sensing

Injection locking of two DFB semiconductors opens new possibilities to generate effective signals for optical sensing, in order to reach better performances. Pure wave forms can be generated with qualities exceeding those obtained using external modulators. This is illustrated through the application to the distributed Brillouin sensing that shows significant progress with respect to established techniques. © 2004 IOP Publishing Ltd

Controlling the Frequency-Temperature Sensitivity of a Cryogenic Sapphire Maser Frequency Standard by Manipulating Fe3+ Spins in the Sapphire Lattice

To create a stable signal from a cryogenic sapphire maser frequency standard, the frequency-temperature dependence of the supporting Whispering Gallery mode must be annulled. We report the ability to control this dependence by manipulating the paramagnetic susceptibility of Fe3+ ions in the sapphire lattice. We show that the maser signal depends on other Whispering Gallery modes tuned to the pump signal near 31 GHz, and the annulment point can be controlled to exist between 5 to 10 K depending on the Fe3+ ion concentration and the frequency of the pump. This level of control has not been achieved previously, and will allow improvements in the stability of such devices.Comment: 17 pages, 10 figure

Absorbing boundary conditions for the Westervelt equation

The focus of this work is on the construction of a family of nonlinear absorbing boundary conditions for the Westervelt equation in one and two space dimensions. The principal ingredient used in the design of such conditions is pseudo-differential calculus. This approach enables to develop high order boundary conditions in a consistent way which are typically more accurate than their low order analogs. Under the hypothesis of small initial data, we establish local well-posedness for the Westervelt equation with the absorbing boundary conditions. The performed numerical experiments illustrate the efficiency of the proposed boundary conditions for different regimes of wave propagation