A5066379762- Cold Atom Physics and Bose-Einstein Condensates
- Atomic and Subatomic Physics Research
- Advanced Frequency and Time Standards
- Quantum optics and atomic interactions
- Quantum Information and Cryptography
- Geophysics and Sensor Technology
- Radioactive Decay and Measurement Techniques
- Advanced Materials Characterization Techniques
- Quantum Mechanics and Applications
- Mechanical and Optical Resonators
- Scientific Measurement and Uncertainty Evaluation
- Advanced Fiber Laser Technologies
- Adhesion, Friction, and Surface Interactions
- Quantum and electron transport phenomena
- Atomic and Molecular Physics
- Silicone and Siloxane Chemistry
- Geophysics and Gravity Measurements
- Surface Roughness and Optical Measurements
- Metallic Glasses and Amorphous Alloys
- Quantum Electrodynamics and Casimir Effect
- Semiconductor materials and devices
- Advanced Fiber Optic Sensors
- Advanced Thermodynamic Systems and Engines
- Inertial Sensor and Navigation
- Magnetic Properties and Applications
Systèmes de Référence Temps-Espace
2015-2025
Centre National de la Recherche Scientifique
2008-2023
Université Paris Sciences et Lettres
2016-2023
Sorbonne Université
2014-2023
Observatoire de Paris
2018-2021
Deleted Institution
2006-2018
Laboratoire National de Métrologie et d'Essais
2018
Laboratoire Charles Fabry
2008-2009
Université Paris-Saclay
2008
Université Paris Cité
2006-2008
We present a classical analog for Electromagnetically Induced Transparency (EIT). In system of just two coupled harmonic oscillators subject to driving force we can reproduce the phenomenology observed in EIT. describe simple experiment performed with linearly RLC circuits which be taught an undergraduate laboratory class.
We report the operation of a cold-atom inertial sensor which continuously captures rotation signal. Using joint interrogation scheme, where we simultaneously prepare source and operate an atom interferometer (AI) enables us to eliminate dead times. show that such continuous improves short-term sensitivity AIs, demonstrate $100\ \text{nrad.s}^{-1}.\text{Hz}^{-1/2}$ in gyroscope $11 \ \text{cm}^2$ Sagnac area. also stability $1 \text{nrad.s}^{-1}$ at $10^4$ s integration time, establishes...
This work reviews the topic of rotation sensing with compact cold atom interferometers. A representative set free-falling gyroscopes is considered because, in different respects, they establish a rotation-measurement reference for guided-atom technologies. review first discusses enabling technologies relevant to key functional building blocks an chip-based inertial sensor guided atoms. These functionalities concern accurate and reproducible positioning atoms initiate measurement cycle,...
We report on the nondestructive observation of Rabi oscillations Cs clock transition. The internal atomic state evolution a dipole-trapped ensemble cold atoms is inferred from phase shift probe laser beam as measured using Mach-Zehnder interferometer. describe single color well two-color probing scheme. Using latter, measurements collective pseudospin projection in superposition states are performed and observed spin fluctuations shown to be close standard quantum limit.
Developments in atom interferometry have led to atomic inertial sensors with extremely high sensitivity. Their performances are for the moment limited by ground vibrations, impact of which is exacerbated sequential operation, resulting aliasing and dead time. We discuss several experiments performed at LNE-SYRTE order reduce these problems achieve intrinsic limit sensors. These techniques resulted transportable high-performance instruments that participate gravity measurements, pave way...
Gravitational Waves (GWs) were observed for the first time in 2015, one century after Einstein predicted their existence. There is now growing interest to extend detection bandwidth low frequency. The scientific potential of multi-frequency GW astronomy enormous as it would enable obtain a more complete picture cosmic events and mechanisms. This unique entirely new opportunity future astronomy, success which depends upon decisions being made on existing infrastructures. prospect combining...
We investigate theoretically and experimentally a nondestructive interferometric measurement of the state population an ensemble laser-cooled trapped atoms. This study is step toward generation (pseudo)spin squeezing cold atoms targeted at improvement cesium clock performance beyond limit set by quantum projection noise calculate phase shift near-resonant optical probe pulse propagating through cloud $^{133}\mathrm{Cs}$ analyze figure merit for nondemolition (QND) collective pseudospin show...
We present a method to suppress the roughness of potential wire-based, magnetic atom guide: modulating wire current at few tens kHz, roughness, which is proportional current, averages zero. Using ultracold $^{87}\mathrm{Rb}$ clouds, we show experimentally that modulation reduces by least factor five without measurable heating or loss. This suppression results in dramatic reduction damping center-of-mass oscillations.
We propose a method of joint interrogation in single atom interferometer which overcomes the dead time between consecutive measurements standard cold atomic fountains. The operation enables for faster averaging Dick effect associated with local oscillator noise clocks and vibration inertial sensors. Such an allows one to achieve lowest stability limit due shot noise. demonstrate multiple up five clouds atoms are interrogated simultaneously setup. essential feature operation, demonstrated...
Using the platform of a trapped-atom clock on chip, we observe time evolution spin-squeezed hyperfine states in ultracold rubidium atoms previously inaccessible scales up to 1 s. The spin degree freedom remains squeezed after 0.6 s, which is consistent with limit imposed by particle loss and compatible typical Ramsey times state-of-the-art microwave clocks. results also reveal surprising spin-exchange interaction effect that amplifies cavity-based measurement via correlation between external...
We have measured the intensity fluctuations of pump and probe beams after interaction with Rb atoms in a situation Electromagnetically Induced Transparency. Both fields present super-Poissonian statistics their intensities become correlated, good qualitative agreement theoretical predictions which both are treated quantum-mechanically. The correlations first step towards observation entanglement between fields.
A theoretical investigation for implementing a scheme of forced evaporative cooling in radio-frequency (rf) adiabatic potentials is presented. Supposing the atoms to be trapped by rf field RF1, procedure facilitated using second source RF2. This produces controlled coupling between spin states dressed RF1. The evaporation then possible pulsed or continuous mode. In case, with given energy are transferred into untrapped abruptly switching off interaction. it energetic adiabatically follow...
Abstract Cold atom quantum sensors based on interferometry are among the most accurate instruments used in fundamental physics, metrology, and foreseen for autonomous inertial navigation. However, they typically have optically complex, cumbersome, low-bandwidth detection systems, limiting their practical applications. Here, we demonstrate an enabling technology high-bandwidth, compact, nondestructive of cold atoms, using microwave radiation. We measure reflected signal to coherently...
A method for nondestructive characterization of a dipole-trapped atomic sample is presented. It relies on measurement the phase shift imposed by cold atoms an optical pulse that propagates through free-space Mach-Zehnder interferometer. Using this technique we are able to determine, with very good accuracy, relevant trap parameters such as temperature, oscillation frequencies, and loss rates. Another important feature our faster than conventional absorption or fluorescence techniques,...
We describe an experiment where spin squeezing occurs spontaneously within a standard Ramsey sequence driving two-component Bose–Einstein condensate (BEC) of 87Rb atoms trapped in elongated magnetic trap. The is generated by state-dependent collisional interactions, despite the near-identical scattering lengths states 87Rb. In our proof-of-principle experiment, we observe metrological that reaches 1.3 ± 0.4 dB for 5000 atoms, with contrast 90 1%. method may be applied to realize...
We observe the spontaneous evaporation of atoms confined in a bubble-like radio frequency (rf)-dressed trap (Zobay and Garraway 2001 Phys. Rev. Lett. 86 1195; 2004 A 69 023605). The are quadrupole magnetic dressed by linearly polarized rf field. is related to presence holes trap, at positions where coupling vanishes, due its vectorial character. final temperature results from competition between residual heating efficiency, which controlled via height with respect bottom trap. experimental...
We proposed the European Laboratory for Gravitation and Atom-interferometric Research (ELGAR), an array of atom gradiometers aimed at studying space-time gravitation with primary goal observing gravitational waves (GWs) in infrasound band a peak strain sensitivity $3.3 \times 10^{-22}/\sqrt{\text{Hz}}$ 1.7 Hz. In this paper we detail main technological bricks large scale detector emphasis research pathways to be conducted its realization. discuss site options, optics, source requirements...
We present a simple method to include the effects of diffraction into description light-atomic ensemble quantum interface in context collective variables. Carrying out scattering calculation we single purely geometrical effect. apply our experimentally relevant case Gaussian shaped atomic samples stored beam optical dipole traps and probed by beam. derive analytical scaling relations for effect interaction geometry compare findings results from 1-dimensional models light propagation.
It was recently demonstrated that wire guide roughness can be suppressed by modulating the currents so atoms experience a time-averaged potential without roughness. We theoretically study limitations of this technique. At low modulation frequency, we show longitudinal produces heating cloud and compute rate. also give quantum derivation rough conservative associated with micro-motion atoms. large loss rate due to non adiabatic spin flip it presents resonnances at multiple frequencies. These...
We present a review of the Optical Parametric Oscillator (OPO), describing its operation and quantum correlation between light beams generated by this oscillator. show construction an OPO using Potassium Titanyl Phosphate crystal (KTP), pumped frequency doubled Nd:YAG laser, discuss stability system related thermal effects. have measured signal idler in transient regime, obtaining noise level 39 % below shot level.