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Your search keyword '"Vincent Dugrain"' showing total 4 results
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4 results on '"Vincent Dugrain"'

1. Spontaneous spin squeezing in a rubidium BEC

Author

Théo Laudat, Vincent Dugrain, Tommaso Mazzoni, Meng-Zi Huang, Carlos L Garrido Alzar, Alice Sinatra, Peter Rosenbusch, and Jakob Reichel

Subjects
spin squeezing, quantum metrology, atom chips, Bose–Einstein condensate, Science, Physics, QC1-999
Abstract

We describe an experiment where spin squeezing occurs spontaneously within a standard Ramsey sequence driving a two-component Bose–Einstein condensate (BEC) of ^87 Rb atoms trapped in an elongated magnetic trap. The squeezing is generated by state-dependent collisional interactions, despite the near-identical scattering lengths of the spin states in ^87 Rb. In our proof-of-principle experiment, we observe a metrological spin squeezing that reaches 1.3 ± 0.4 dB for 5000 atoms, with a contrast of 90 ± 1%. The method may be applied to realize spin-squeezed BEC sources for atom interferometry without the need for cavities, state-dependent potentials or Feshbach resonances.

Published
2018
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2. Effect of supplementary implantation of a sulcus-fixated intraocular lens in patients with negative dysphotopsia

Author

Vincent Dugrain, Rudy M.M.A. Nuijts, Daniel Purchase, Tos T. J. M. Berendschot, Natalia Y. Makhotkina, Medical Image Analysis, MUMC+: MA UECM AIOS (9), Oogheelkunde, MUMC+: MA UECM Oogartsen MUMC (9), RS: MHeNs - R3 - Neuroscience, RS: NUTRIM - R1 - Obesity, diabetes and cardiovascular health, and MUMC+: *AB Refractie Chirurgie Oogheelkunde (9)

Subjects
Male, SYMPTOMS, genetic structures, medicine.medical_treatment, Intraocular lens, 01 natural sciences, 0302 clinical medicine, Lens Implantation, Intraocular, Medicine, University medical, Lenses, Visual Fields/physiology, Lenses, Intraocular, Intraocular, Sulcus, Middle Aged, Sensory Systems, ETIOLOGY, Visual field, medicine.anatomical_structure, Lens Implantation, Intraocular/methods, Female, Lens Implantation, Retina/physiology, Reoperation, medicine.medical_specialty, Biometry, Pseudophakia, Intraocular/methods, Vision Disorders, Phacoemulsification/methods, Retina, 010309 optics, 03 medical and health sciences, Ophthalmology, 0103 physical sciences, Small pupil, Journal Article, MANAGEMENT, Humans, In patient, Negative dysphotopsia, Aged, Retrospective Studies, Pseudophakia/physiopathology, Phacoemulsification, Vision Disorders/surgery, business.industry, Suture Techniques, eye diseases, 030221 ophthalmology & optometry, Visual Field Tests, Surgery, FAR PERIPHERAL-VISION, sense organs, Visual Fields, business, Light irradiance
Abstract

PURPOSE: To evaluate whether the outcome of negative dysphotopsia treatment by implantation of a Sulcoflex intraocular lens (IOL) can be understood using individual biometry and optical modeling data.SETTING: University Eye Clinic, Maastricht University Medical Centre, Maastricht, the Netherlands.DESIGN: Retrospective case series.METHODS: Patients with negative dysphotopsia were treated with supplementary implantation of a sulcus-fixated IOL. Preoperative and postoperative ray-tracing optical models of eyes with negative dysphotopsia were constructed in the Zemax Optic Studio program using individual biometric data. The relationship between biometric parameters, ray-tracing data, and the course of negative dysphotopsia was evaluated.RESULTS: The study comprised 8 patients (10 eyes). After surgery, negative dysphotopsia resolved completely in 6 eyes, partially in 2 eyes, and persisted in 2 eyes. There was no relationship between the course of negative dysphotopsia and age, IOL power, or individual biometry results other than a larger angle κ that was observed in 2 patients with persistent negative dysphotopsia after surgery. Preoperative ray-tracing models showed a decrease in light irradiance at the periphery relative to the center of visual field. After sulcus-fixated IOL implantation, this decrease partially resolved, in particular, for a small pupil aperture (P < .05), and it was more prominent in patients in whom negative dysphotopsia resolved completely than in those with partial or persistent negative dysphotopsia (P = .065 at 1.5 mm aperture).CONCLUSIONS: Of all individual biometry results, only angle κ showed a relationship with the course of negative dysphotopsia. In patient-specific optical modeling of sulcus-fixated IOL implantation, the increase in simulated light irradiance at the periphery was related to the course of negative dysphotopsia.

Published
2017

3. Stability of a trapped-atom clock on a chip

Author

Vincent Dugrain, R. Szmuk, W. Maineult, Peter Rosenbusch, Jakob Reichel, Systèmes de Référence Temps Espace (SYRTE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Kastler Brossel (LKB (Jussieu)), Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Kastler Brossel (LKB (Lhomond)), Université Pierre et Marie Curie - Paris 6 (UPMC)-Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Atomic Physics (physics.atom-ph), Atom chip, FOS: Physical sciences, Metrology, 7. Clean energy, Physics - Atomic Physics, 67.85.-d, Computer Science::Hardware Architecture, Ultracold atom, Time and frequency, Physics::Atomic and Molecular Clusters, Physics::Atomic Physics, 06.30.Ft, [PHYS]Physics [physics], Condensed Matter::Quantum Gases, Physics, Quantum Physics, 37.10.Gh, Ultracold gases trapped gases, Chip, Atomic and Molecular Physics, and Optics, Atomic clock, Atom traps and guides, 06.20.-f, Atomic physics, Quantum Physics (quant-ph), [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

We present a compact atomic clock interrogating ultracold 87Rb magnetically trapped on an atom chip. Very long coherence times sustained by spin self-rephasing allow us to interrogate the atomic transition with 85% contrast at 5 s Ramsey time. The clock exhibits a fractional frequency stability of $5.8\times 10^{-13}$ at 1 s and is likely to integrate into the $1\times10^{-15}$ range in less than a day. A detailed analysis of 7 noise sources explains the measured frequency stability. Fluctuations in the atom temperature (0.4 nK shot-to-shot) and in the offset magnetic field ($5\times10^{-6}$ relative fluctuations shot-to-shot) are the main noise sources together with the local oscillator, which is degraded by the 30% duty cycle. The analysis suggests technical improvements to be implemented in a future second generation set-up. The results demonstrate the remarkable degree of technical control that can be reached in an atom chip experiment., 12 pages, 11 figures

Published
2015
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4. Alkali vapor pressure modulation on the 100 ms scale in a single-cell vacuum system for cold atom experiments

Author

Jakob Reichel, Vincent Dugrain, Peter Rosenbusch, Laboratoire Kastler Brossel (LKB (Jussieu)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire national de métrologie et d'essais - Systèmes de Référence Temps-Espace (LNE - SYRTE), Systèmes de Référence Temps Espace (SYRTE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Kastler Brossel (LKB (Lhomond)), Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Physics - Instrumentation and Detectors, Materials science, Atomic Physics (physics.atom-ph), Vapor pressure, FOS: Physical sciences, Heat sink, 7. Clean energy, Physics - Atomic Physics, Trap (computing), Ultracold atom, Physics::Atomic Physics, Instrumentation, ComputingMilieux_MISCELLANEOUS, Condensed Matter::Quantum Gases, [PHYS]Physics [physics], Quantum Physics, Instrumentation and Detectors (physics.ins-det), Thermal conduction, Alkali metal, Pressure sensor, Quantum Gases (cond-mat.quant-gas), Modulation, Atomic physics, Condensed Matter - Quantum Gases, Quantum Physics (quant-ph), [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract

We describe and characterize a device for alkali vapor pressure modulation on the 100ms timescale in a single-cell cold atom experiment. Its mechanism is based on optimized heat conduction between a current-modulated alkali dispenser and a heat sink at room temperature. We have studied both the short-term behavior during individual pulses and the long-term pressure evolution in the cell. The device combines fast trap loading and relatively long trap lifetime, enabling high repetition rates in a very simple setup. These features make it particularly suitable for portable atomic sensors., Comment: One reference added, one corrected

Published
2014
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