A5047823253- Adaptive optics and wavefront sensing
- Cold Atom Physics and Bose-Einstein Condensates
- Optical Wireless Communication Technologies
- Advanced optical system design
- Quantum chaos and dynamical systems
- Atomic and Subatomic Physics Research
- Optical Systems and Laser Technology
- Planetary Science and Exploration
- Quantum optics and atomic interactions
- Optical Coherence Tomography Applications
- Advanced Frequency and Time Standards
- Stellar, planetary, and galactic studies
- Geophysics and Gravity Measurements
- Advanced Optical Sensing Technologies
- GNSS positioning and interference
- Dark Matter and Cosmic Phenomena
- Meteorological Phenomena and Simulations
- Quantum, superfluid, helium dynamics
- Advanced Measurement and Metrology Techniques
- Solar and Space Plasma Dynamics
- Calibration and Measurement Techniques
- Laser-Matter Interactions and Applications
- Advanced Fiber Optic Sensors
- Optical measurement and interference techniques
- Atmospheric Ozone and Climate
Centre National de la Recherche Scientifique
2013-2024
Observatoire de la Côte d’Azur
2014-2024
Institut de Recherche pour le Développement
2016-2024
Université Côte d'Azur
2013-2024
Géoazur
2016-2023
Royal Observatory of Belgium
2021
Lagrange Laboratory
2015-2020
Ben-Gurion University of the Negev
2010-2014
Université de Toulouse
2012
Laboratoire de Physique des Lasers, Atomes et Molécules
2005-2009
We realize experimentally an atom-optics quantum chaotic system, the quasiperiodic kicked rotor, which is equivalent to a 3D disordered that allow us demonstrate Anderson metal-insulator transition. Sensitive measurements of atomic wavefunction dynamics and use finite-size scaling techniques make it possible extract both critical parameters exponent transition, in good agreement with value obtained numerical simulations model.
Using a cold atomic gas exposed to laser pulses---a realization of the chaotic quasiperiodic kicked rotor with three incommensurate frequencies---we study experimentally and theoretically Anderson metal-insulator transition in dimensions. Sensitive measurements wave function use finite-size scaling techniques make it possible unambiguously demonstrate existence quantum phase measure its critical exponents. By taking proper account systematic corrections one-parameter scaling, we show...
We compare two different models of transport light in a disordered system with spherical Gaussian distribution scatterers. A coupled dipole model, keeping into account all interference effects, is compared to an incoherent using random walk particles. Besides the well known coherent backscattering effect and pronounced forward lobe, model reproduces extremely scattering features. In experiment cold atoms, we use momentum recoil imparted on center mass sample as partial probe properties. find...
The future generation of extremely large telescopes will be certainly equipped with wide-field adaptive optics systems. All the components such systems have to precisely specified, and most technical specifications are related atmospheric turbulence parameters, particularly profile refractive index structure constant <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:msubsup> <mml:mi>C</mml:mi> <mml:mi>n</mml:mi> <mml:mn>2</mml:mn> </mml:msubsup> <mml:mo...
Abstract Based on a fully passive space segment, the lunar laser ranging experiment is last of Apollo Lunar Surface Experiments Package to operate. Observations from Grasse station have been made daily basis since first echoes obtained in 1981. In this paper, first, we review principle and technical aspects ranging. We then give brief summary progress at facility (Observatoire de la Côte d'Azur, Calern Plateau French Riviera) echoes. The current performance, driven by use an infrared...
We present a generalized differential image motion monitor (GDIMM). It is compact instrument dedicated to the measurement of four parameters optical turbulence: seeing, isoplanatic angle, coherence time and wavefront outer scale. The GDIMM based on small telescope (28 cm diameter) equipped with three-hole mask at its entrance pupil. fully automatic, performs continuous monitoring turbulence Calern Observatory (France). This paper gives description instrument, data processing error budget....
ABSTRACT The forecast for atmospheric and turbulence conditions above astronomical observatories is of interest to the community because it allows observations be planned with maximum efficiency, a process called flexible scheduling. It can also used simulate long-term site testing provide local information useful conception focal post-focal instrumentation. We have presented our forecasting tool in previous publications, but this paper we focus on importance using measurements improve...
Downlink measurement campaigns from the optical downlink terminal OSIRISv1 onboard LEO satellite Flying Laptop were carried out with French Observatoire de la Côte d'Azur and two Optical Ground Stations of German Aerospace Center. On/off keyed data at 39 Mb/s modulated on laser signal, according telecom reception was performed by ground stations. The pointing achieved open-loop body orientation, its star sensor as attitude control signal. We report here measurements investigations signal...
We present an analysis of magnetic traps for ultracold atoms based on current-carrying wires with sub-micron dimensions. analyze the physical limitations these conducting wires, as well how such miniaturized are affected by nearby surface due to tunneling surface, thermal noise, electron scattering within wire, and Casimir-Polder force. show that cross sections small a few tens nanometers should enable robust operating conditions coherent atom optics (e.g. barriers interferometry). In...
The possibility for Lorentz and $CPT$ breaking, which is motivated by unification theories, can be systematically tested within the Standard Model extension (SME) framework. In pure gravity sector, mass dimension 5 operators produce new Lorentz- $CPT$-breaking terms in two-body equations of motion that depend on relative velocity bodies, and, hence, they constrained with experiments. this paper, we report constraints 15 independent SME coefficients violations using lunar laser ranging. We...
Dynamical localization is a phenomenon taking place, for example, in the quantum periodically-driven kicked rotor. It due to subtle destructive interferences and thus of intrinsic origin. has been shown that deviation from strict periodicity driving rapidly destroys dynamical localization. We report experimental results showing this destruction partially reversible when deterministic perturbation destroyed it slowly reversed. also provide an explanation partial character reversibility.
For satellite to ground laser links, atmospheric turbulence is a major cause of impairments. The induced phase perturbations along the propagation path beam scintillation in receiver plane and they can also severely compromise coupling flux into limited size. To address these impairments, dedicated mitigation strategies must be developed. This requires accurate understanding perturbation origin. Beam models have demonstrated their ability reproduce statistical characteristics optical on link...
We present first results of a new instrument, the Generalized Differential Image Motion Monitor (GDIMM), aiming at monitoring parameters optical turbulence (seeing, isoplanatic angle, coherence time and outer scale). GDIMM is based on small telescope equipped with 3-holes mask its entrance pupil. The seeing measured by classical DIMM technique using two sub-pupils (6 cm diameter separated distance 20 cm), angle estimated from scintillation through third sub-pupil (its 10 cm, central...
Abstract We present the results of first series successful two-way laser ranging experiments from a ground station, Lunar Laser Ranging (LLR) station in Grasse, France, to spacecraft at lunar distance, Reconnaissance Orbiter (LRO). A 15 × 18 5 cm, 650-g array twelve 32-mm diameter solid corner cubes is mounted on its anti-nadir deck. this small retro-reflector onboard orbiter was challenge compared larger surface retro-reflectors. Grasse measured 67 returns two 6-min sessions September 4,...
Optical system performances can be affected by local optical turbulence created its surrounding environment (telescope dome, clean room, atmospheric surface layer). We present our new instrument INdoor TurbulENce SEnsor (INTENSE) dedicated to this characterization. INTENSE consists of using several parallel laser beams separated non-redundant baselines between 0.05 and 2.5 m measuring the angle arrival fluctuations from spot displacements on a CCD. After introducing theoretical background,...
From its long expertise in Atmospheric Optics, the J.L. Lagrange Laboratory of Observatoire de la Côte d'Azur has developed a new generation autonomous stations atmospheric turbulence measurement. Since two years, Calern Observatory is equipped with this kind called CATS for Turbulence Station. an station consisting set complementary instruments within original techniques measuring optical since first meters above ground to borders atmosphere including dome seeing. Indeed, one PML (Profiler...
We demonstrate tomographic reconstruction of the phase space distribution atoms oscillating in a harmonic trap with weak potential corrugation caused by nanoscale imperfections an atom chip. find that deformations these distributions are highly sensitive to anharmonic components potential. They explained terms angular velocity dispersion isoenergetic trajectories. show method is applicable for probing classical and quantum dynamics cold atoms, we note its importance future technological applications.
From its long expertise in Atmospheric Optics, the Observatoire de la Côte d'Azur and J.L. Lagrange Laboratory have equipped Calern Observatory with a station of atmospheric turbulence measurement (CATS: Turbulence Station). The CATS is set complementary instruments for monitoring parameters. These new-generation are autonomous within original techniques measuring optical since first meters above ground to borders atmosphere. also support our training activities as part Masters MAUCA OPTICS,...
The interplay between the superradiant emission of a cloud cold two-level atoms and radiation pressure force is discussed. Using microscopic model coupled atomic dipoles driven by an external laser, field average are derived. A relation far-field scattered intensity derived, using optical theorem. Finally, scaling sample scattering cross section with parameters system studied.
We study the destruction of dynamical localization experimentally observed in an atomic realization kicked rotor by a deterministic Hamiltonian perturbation, with temporal periodicity incommensurate principal driving. show that is gradual, well-defined scaling laws for various classical and quantum parameters, sharp contrast to predictions based on analogy Anderson localization.
To reach a high performance with an adaptive optics system, we need calibration using reference source. This latter should be located in the same isoplanatic domain as science Different techniques and methods have been developed leading to estimations of patch but all are model-dependent. We new technique for estimation angle based on extended object. is now part our turbulence profile monitor PML (Profiler Moon Limb) observation limb or Sun edge. The first statistics this presented compared...