Author: "RTRA Triangle de la Physique" - Searchworks@Jio Institute Digital Library Search Results

Your search keyword '"RTRA Triangle de la Physique"' showing total 47 results

Start Over Author "RTRA Triangle de la Physique"

47 results on '"RTRA Triangle de la Physique"'

1. A pressure-actuated flow cell for soft X-ray spectromicroscopy in liquid media

Author: Corinne Chevallard, Charlie Gosse, Patrick Haltebourg, Benjamin Watts, Christian Blot, Rachid Belkhou, Aymeric Vecchiola, Stefan Stanescu, Mélanie Moskura, Sufal Swaraj, Patrick Guenoun, Stéphane Lefrançois, J. Daillant, Joni Frederick, Centre de Nanosciences et de Nanotechnologies (C2N), Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Laboratoire Interdisciplinaire sur l'Organisation Nanométrique et Supramoléculaire (LIONS), Nanosciences et Innovation pour les Matériaux, la Biomédecine et l'Energie (ex SIS2M) (NIMBE UMR 3685), Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Synchrotron SOLEIL, Laboratoire Structure et Dynamique par Résonance Magnétique (LCF) (LSDRM), Paul Scherrer Institute (PSI), RTRA Triangle de la Physique: grants 'FluBioMix' and 'FluBioMix 2', C'Nano Ile de France: grant 'Capress', ANR-10-EQPX-0050,TEMPOS,Microscopie electronique en transmission sur le plateau Palaiseau Orsay Saclay(2010), ANR-10-LABX-0035,Nano-Saclay,Paris-Saclay multidisciplinary Nano-Lab(2010), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Diffraction, Materials science, Scattering, Microfluidics, Biomedical Engineering, Bioengineering, Nanotechnology, 02 engineering and technology, General Chemistry, [CHIM.MATE]Chemical Sciences/Material chemistry, Radiation, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, Biochemistry, 0104 chemical sciences, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, Fluidics, 0210 nano-technology, Nanoscopic scale, Beam (structure), Microfabrication
Abstract: International audience; We present and fully characterize a flow cell dedicated to imaging in liquid at the nanoscale. Its use as a routine sample environment for soft X-ray spectromicroscopy is demonstrated, in particular through the spectral analysis of inorganic particles in water. The care taken in delineating the fluidic pathways and the precision associated with pressure actuation ensure the efficiency of fluid renewal under the beam, which in turn guarantees a successful utilization of this microfluidic tool for in situ kinetic studies. The assembly of the described flow cell necessitates no sophisticated microfabrication and can be easily implemented in any laboratory. Furthermore, the design principles we relied on are transposable to all microscopies involving strongly absorbed radiations (e.g. X-ray, electron), as well as to all kinds of X-ray diffraction/scattering techniques.
Published: 2020
Full Text: View/download PDF

2. Spectroscopy of methylcyanodiacetylene revisited. Solid parahydrogen and solid neon matrix studies

Author: Robert Kołos, Michał Turowski, Claudine Crépin, Jean-Claude Guillemin, Urszula Szczepaniak, Alejandro Gutiérrez-Quintanilla, Thomas Custer, Institut des Sciences Moléculaires d'Orsay (ISMO), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Polish Academy of Sciences (PAN), Universidad de La Habana [Cuba], Institut des Sciences Chimiques de Rennes (ISCR), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA), This study was supported with the funds of the Polish National Science Centre, project No. 2011/03/B/ST4/02763, the French-Polish PICS project (2014–2016) and the RTRA Triangle de la Physique (2013-0436T REACMAQ)., Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics::General Physics, Polyyne, Analytical chemistry, chemistry.chemical_element, Infrared spectroscopy, 010402 general chemistry, Spin isomers of hydrogen, 01 natural sciences, Matrix isolation, Spectral line, Analytical Chemistry, Inorganic Chemistry, Neon, Ultraviolet visible spectroscopy, [CHIM]Chemical Sciences, UV/Vis spectroscopy, Spectroscopy, 010405 organic chemistry, Chemistry, Phosphorescence, Organic Chemistry, 0104 chemical sciences, IR spectroscopy
Abstract: International audience; Electronic phosphorescence and infrared absorption spectra of methylcyanodiacetylene (CH3C5N) are revisited using matrix isolation in solid parahydrogen and neon. Band assignments previously found for Ar, Kr, Xe, and N2 low-temperature host media were updated, with certain ambiguous attributions being resolved. A combined analysis of both dispersed phosphorescence and phosphorescence excitation spectra observed in different environments provides a means to estimate the singlet-triplet separation for the gas-phase and pure solid compound, where phosphorescence could not be observed.
Published: 2020
Full Text: View/download PDF

3. Controlling the magnetic exchange coupling in hybrid heterojunctions via spacer layers of π -conjugated molecules

Author: Alexander Smogunov, Pierre Bonville, Camille Blouzon, Dongzhe Li, Ludovic Tortech, Jean-Baptiste Moussy, Quentin Arnoux, Yannick J. Dappe, Laboratoire Innovation en Chimie des Surfaces et NanoSciences (LICSEN UMR 3685), Nanosciences et Innovation pour les Matériaux, la Biomédecine et l'Energie (ex SIS2M) (NIMBE UMR 3685), Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut Parisien de Chimie Moléculaire (IPCM), Chimie Moléculaire de Paris Centre (FR 2769), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Nano-Magnétisme et Oxydes (LNO), Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Groupe Modélisation et Théorie (GMT), RTRA 'triangle de la Physique': project HeteroSpinMol, Laboratoire Innovation en Chimie des Surfaces et NanoSciences (LICSEN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC), Institut de Chimie du CNRS (INC)-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)-Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL (ENSCP), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Service de physique de l'état condensé (SPEC - UMR3680), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Coupling, Materials science, Condensed matter physics, Spintronics, Heterojunction, 02 engineering and technology, [CHIM.MATE]Chemical Sciences/Material chemistry, 021001 nanoscience & nanotechnology, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 01 natural sciences, Inductive coupling, Magnetization, Condensed Matter::Materials Science, Ferromagnetism, Ab initio quantum chemistry methods, Condensed Matter::Superconductivity, 0103 physical sciences, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Antiferromagnetism, 010306 general physics, 0210 nano-technology
Abstract: Mastering and understanding the magnetic couplings between magnetic electrodes separated by organic layers are crucial for developing new hybrid spintronic devices. We study the magnetic exchange interactions in organic-inorganic heterojunctions and unveil the possibility of controlling the strength of the magnetic exchange coupling between two ferromagnetic electrodes across $\ensuremath{\pi}$-conjugated molecules' ($\ensuremath{\alpha}$-sexithiophene or para-sexiphenyl) ultrathin film. In $\mathrm{F}{\mathrm{e}}_{3}{\mathrm{O}}_{4}/\ensuremath{\pi}$-conjugated molecules/Co magnetic tunnel junctions, an antiferromagnetic interlayer exchange coupling with variable strength is observed according to the nature of the aromatic rings (thiophene or phenyl groups). The underlying physical mechanism is revealed by ab initio calculations relating the strength of magnetic coupling to the spin moment penetration into a molecular layer at the molecule/Co interface. The prospect that magnetic coupling between two ferromagnetic electrodes can be mediated and tuned by organic molecules opens different perspectives in the way magnetization of organic tunnel junctions or spin valves can be driven.
Published: 2019
Full Text: View/download PDF

4. Understanding the STM images of epitaxial graphene on a reconstructed 6H-SiC(0001) surface: the role of tip-induced mechanical distortion of graphene

Author: Thoyer, François, Lubin, Christophe, Cousty, Jacques, Morán-Meza, José A., Laboratoire Nano-Magnétisme et Oxydes (LNO), Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire d'Electronique et nanoPhotonique Organique (LEPO), Laboratoire d'Etude des NanoStructures et Imagerie de Surface (LENSIS), J.-A.M.M. would also like to acknowledge financial support from Réseau Thématique de Recherche Avancée(RTRA-Triangle de la Physique) and CEA/Direction des Relations Internationales (DRI)., and jacques.cousty@cea.fr
Subjects: Microscope, Materials science, Scanning Tunneling Microscopy (STM), General Physics and Astronomy, Atomic Force Microscopy (AFM), Silicon carbide, 02 engineering and technology, 01 natural sciences, Molecular physics, law.invention, chemistry.chemical_compound, Optics, law, Lattice (order), 0103 physical sciences, Hexagonal lattice, Physical and Theoretical Chemistry, 010306 general physics, [PHYS]Physics [physics], Local density of states, Mechanical distortion, business.industry, Graphene, 021001 nanoscience & nanotechnology, Epitaxial graphene, chemistry, Density functional theory, Scanning tunneling microscope, 0210 nano-technology, business
Abstract: International audience; Epitaxial graphene (EG) grown on an annealed 6H-SiC(0001) surface has been studied under ultra-high vacuum (UHV) conditions by using a combined dynamic-scanning tunneling microscope/frequency modulation-atomic force microscope (dynamic-STM/FM-AFM) platform based on a qPlus probe. STM and AFM images independently recorded present the same hexagonal lattice of bumps with a 1.9 nm lattice period, which agrees with density functional theory (DFT) calculations and experimental results previously reported, attributed to the (6 x 6) quasi-cell associated with the 6H-SiC(0001) (6$\sqrt 3$x6$\sqrt 3$) R30 reconstruction. However, topographic bumps in AFM images and maxima in the simultaneously recorded mean-tunneling-current map do not overlap but appear to be spaced typically by about 1 nm along the [11] direction of the (6 x 6) quasi-cell. A similar shift is observed between the position of maxima in dynamic-STM images and those in the simultaneously recorded frequency shift map. The origin of these shifts is discussed in terms of electronic coupling variations between the local density of states (LDOS) of EG and the LDOS of the buffer layer amplified by mechanical distortions of EG induced by the STM or AFM tip. Therefore, a constant current STM image of EG on a reconstructed 6H-SiC(0001) surface does not reproduce its real topography but corresponds to the measured LDOS modulations, which depend on the variable tip-induced graphene distortion within the (6 x 6) quasi-cell.
Published: 2016
Full Text: View/download PDF

5. A microdevice to locally electroporate embryos with high efficiency and reduced cell damage

Author: Xuan Zhao, Isabelle Migeotte, Charlie Gosse, Aitana Perea-Gomez, Elsa Mazari, Jérôme Collignon, Laboratoire de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), Institut de Recherche Interdisciplinaire en Biologie Humaine et Moleculaire, Université Libre de Bruxelles [Bruxelles] (ULB), Institut Jacques Monod (IJM (UMR_7592)), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), ElectroMice, Biomodulator and ElectroTagMan grants, the Centre National de la Recherche Scientifique (CNRS) PI 2008, Agence Nationale de la Recherche (ANR) PNANO 2009, C'nano IdF 2011 calls, Fondation pour la Recherche Medicale (FRM), the Reseau Thematique de Recherche Avancee (RTRA) 'Triangle de la Physique' (ElectroMagSign project, Fonds National de la Recherche Scientifique (FNRS), and Université libre de Bruxelles (ULB)
Subjects: Male, Finite Element Analysis, Population, Cell, Finite element model simulations, Mice, Transgenic, Biology, Mouse embryo, Visceral endoderm, Mice, 03 medical and health sciences, 0302 clinical medicine, Cell Movement, Live cell imaging, medicine, Animals, Computer Simulation, education, [SDV.BDD]Life Sciences [q-bio]/Development Biology, Molecular Biology, Cell damage, Migration, Fluorescent Dyes, 030304 developmental biology, 0303 health sciences, education.field_of_study, Microscopy, Confocal, Miniaturization, Electroporation, Endoderm, Microsystem, Organ explant, Embryo, Equipment Design, Anatomy, Transfection, Models, Theoretical, Embryo, Mammalian, medicine.disease, Cell biology, Mice, Inbred C57BL, medicine.anatomical_structure, Localised electroporation, Female, 030217 neurology & neurosurgery, Developmental Biology
Abstract: International audience; : The ability to follow and modify cell behaviour with accurate spatiotemporal resolution is a prerequisite to study morphogenesis in developing organisms. Electroporation, the delivery of exogenous molecules into targeted cell populations through electric permeation of the plasma membrane, has been used with this aim in different model systems. However, current localised electroporation strategies suffer from insufficient reproducibility and mediocre survival when applied to small and delicate organisms such as early post-implantation mouse embryos. We introduce here a microdevice to achieve localised electroporation with high efficiency and reduced cell damage. In silico simulations using a simple electrical model of mouse embryos indicated that a dielectric guide-based design would improve on existing alternatives. Such a device was microfabricated and its capacities tested by targeting the distal visceral endoderm (DVE), a migrating cell population essential for anterior-posterior axis establishment. Transfection was efficiently and reproducibly restricted to fewer than four visceral endoderm cells without compromising cell behaviour and embryo survival. Combining targeted mosaic expression of fluorescent markers with live imaging in transgenic embryos revealed that, like leading DVE cells, non-leading ones send long basal projections and intercalate during their migration. Finally, we show that the use of our microsystem can be extended to a variety of embryological contexts, from preimplantation stages to organ explants. Hence, we have experimentally validated an approach delivering a tailor-made tool for the study of morphogenesis in the mouse embryo. Furthermore, we have delineated a comprehensive strategy for the development of ad hoc electroporation devices.
Published: 2014
Full Text: View/download PDF

6. Nanostructuration of Cr/Si layers induced by ion beam mixing

Author: Gianguido Baldinozzi, Laurence Luneville, Cyrile Deranlot, Ludovic Largeau, Frédéric Ott, Nathalie Moncoffre, David Simeone, Yves Serruys, Laboratoire Structures, Propriétés et Modélisation des solides (SPMS), Institut de Chimie du CNRS (INC)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Département de Modélisation des Systèmes et Structures (DM2S), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), Unité mixte de physique CNRS/Thales (UMPhy CNRS/THALES), Centre National de la Recherche Scientifique (CNRS)-THALES, Institut de Physique Nucléaire de Lyon (IPNL), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Service de recherches de métallurgie physique (SRMP), Département des Matériaux pour le Nucléaire (DMN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Laboratoire Léon Brillouin (LLB - UMR 12), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay, Laboratoire d'Analyse Microstructurale des Matériaux (LA2M), Service des Recherches Métallurgiques Appliquées (SRMA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Département des Matériaux pour le Nucléaire (DMN), RTRA Triangle de la physique, 2011-074T, INSTRUMAT, THALES [France]-Centre National de la Recherche Scientifique (CNRS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, Ion beam analysis, Ion beam mixing, business.industry, Analytical chemistry, 02 engineering and technology, 021001 nanoscience & nanotechnology, Microstructure, 01 natural sciences, Focused ion beam, X-ray reflectivity, 0103 physical sciences, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Microelectronics, Irradiation, 010306 general physics, 0210 nano-technology, Reflectometry, business
Abstract: This work clearly demonstrates that the X Ray Reflectometry technique (XRR), extensively used to assess the quality of microelectronic devices can be a useful tool to study the first stages of ion beam mixing. This technique allows measuring the evolution of the Si concentration profile in irradiated Cr/Si layers. From the analysis of the XRR profiles, it clearly appears that the Si profile cannot be described by a simple error function.
Published: 2013
Full Text: View/download PDF

7. An attempt to handle the nanopatterning of materials created under ion beam mixing

Author: David Simeone, Gilles Demange, Yanwen Zhang, Dominique Gosset, Laurence Luneville, Gianguido Baldinozzi, Laboratoire Structures, Propriétés et Modélisation des solides (SPMS), Institut de Chimie du CNRS (INC)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Analyse Microstructurale des Matériaux (LA2M), Service des Recherches Métallurgiques Appliquées (SRMA), Département des Matériaux pour le Nucléaire (DMN), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Département des Matériaux pour le Nucléaire (DMN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Materials Science and Engineering (UT Knoxville), The University of Tennessee [Knoxville], Département de Modélisation des Systèmes et Structures (DM2S), RTRA Triangle de la physique, 2011-074T, INSTRUMAT, Institut de Chimie du CNRS (INC)-CentraleSupélec-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Materials Science and Technology Division [Oak Ridge], Oak Ridge National Laboratory [Oak Ridge] (ORNL), UT-Battelle, LLC-UT-Battelle, LLC, and Service d’Études des Réacteurs et de Mathématiques Appliquées (SERMA)
Subjects: [PHYS]Physics [physics], Materials science, Ion beam analysis, Condensed matter physics, Ion beam mixing, Microstructure, 01 natural sciences, 010305 fluids & plasmas, Mean field theory, 0103 physical sciences, X-ray crystallography, Nano, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Diffusion (business), 010306 general physics, Structure factor
Abstract: In the past fifty years, experimental works based on TEM or grazing incidence X ray diffraction have clearly shown that alloys and ceramics exhibit a nano pattering under irradiation [1,2,3]. Many works were devoted to study the nano patterning induced by ion beam mixing in solids [17,18,19]. Understanding the nano patterning will provide scientific bases to tailor materials with well-defined microstructures at the nanometric scale. The slowing down of impinging particles in solids leads to a complex distribution of subcascades. Each subcascade will give rise to an athermal diffusion of atoms in the medium. In this work, we focused on this point. Based on the well-known Cahn Hilliard Cook (CHC) equation, we analytically calculate the structure factor describing the nano patterning within the mean field approximation. It has shown that this analytical structure factor mimics the structure factor extracted from direct numerical simulations of the time dependent CHC equation. It appears that this structure factor exhibits a universal feature under irradiation.
Published: 2013
Full Text: View/download PDF

8. Local recording of biological magnetic fields using Giant Magneto Resistance-based micro-probes

Author: Barbieri, Francesca, Trauchessec, Vincent, Caruso, Laure, Trejo-Rosillo, Josué, Telenczuk, Bartosz, Paul, Elodie, Bal, Thierry, Destexhe, Alain, Fermon, Claude, Pannetier-Lecoeur, Myriam, Ouanounou, Gilles, Centre de neurophysique, physiologie, pathologie (UMR 8119), Université Paris Descartes - Paris 5 (UPD5)-Centre National de la Recherche Scientifique (CNRS), Unité de Neurosciences Information et Complexité [Gif sur Yvette] (UNIC), Centre National de la Recherche Scientifique (CNRS), Institut des Neurosciences Paris-Saclay (NeuroPSI), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Nano-Magnétisme et Oxydes (LNO), Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, This work was supported by Commissariat à l’Energie Atomique and Centre National de Recherche Scientifique.Also the Magsondes project by RTRA-Triangle de La Physique, European Project: 600730,EC:FP7:ICT,FP7-ICT-2011-9,MAGNETRODES(2013), European Project: 604102,EC:FP7:ICT,FP7-ICT-2013-FET-F,HBP(2013), and Institut des Neurosciences de Paris-Saclay (Neuro-PSI)
Subjects: [PHYS]Physics [physics], Action Potentials, equipment and supplies, Article, Electrophysiological Phenomena, Magnetics, Mice, Membrane biophysics, Magnetic Fields, Animals, Computer Simulation, Muscle, Skeletal, human activities, Sensors and probes
Abstract: International audience; The electrical activity of brain, heart and skeletal muscles generates magnetic fields but these arerecordable only macroscopically, such as in magnetoencephalography, which is used to map neuronalactivity at the brain scale. At the local scale, magnetic fields recordings are still pending because ofthe lack of tools that can come in contact with living tissues. Here we present bio-compatible sensorsbased on Giant Magneto-Resistance (GMR) spin electronics. We show on a mouse muscle in vitro,using electrophysiology and computational modeling, that this technology permits simultaneouslocal recordings of the magnetic fields from action potentials. The sensitivity of this type of sensoris almost size independent, allowing the miniaturization and shaping required for in vivo/vitromagnetophysiology. GMR-based technology can constitute the magnetic counterpart of microelectrodesin electrophysiology, and might represent a new fundamental tool to investigate the local sources ofneuronal magnetic activity.
Published: 2016
Full Text: View/download PDF

9. Is the Reaction of C3N(-) with C2H2 a Possible Process for Chain Elongation in Titan's Ionosphere?

Author: Claire Romanzin, Allan Lopes, Daniela Ascenzi, Leopold Koch, Illia Zymak, Miroslav Polášek, Christian Alcaraz, Wolf D. Geppert, Jean-Claude Guillemin, Fredrik Lindén, Ján Žabka, Laboratoire de Chimie Physique D'Orsay (LCPO), Université Paris-Sud - Paris 11 (UP11)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Fisica [Povo], Università degli Studi di Trento (UNITN), Institut des Sciences Chimiques de Rennes (ISCR), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), J. Heyrovský Institute of Physical Chemistry of the ASCR, Czech Academy of Sciences [Prague] (CAS), COST Action (Origins and Evolution of Life on Earth and in the Universe) [TD1308], COST Action (Our Astro-Chemical History) [CM1401], Czech Science Foundation [14-19693S, 14-20915S], French program of planetology (PNP), RTRA 'Triangle de la Physique' [2012-027T - GIN], Department of Physics at Trento University, Centre National d'Etudes Spatiales (CNES), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 010504 meteorology & atmospheric sciences, Ion beam, h-atoms, Analytical chemistry, mechanism, chemistry, 01 natural sciences, Dissociation (chemistry), chemistry.chemical_compound, symbols.namesake, carbanions, Ab initio quantum chemistry methods, 0103 physical sciences, [CHIM]Chemical Sciences, Physical and Theoretical Chemistry, 010303 astronomy & astrophysics, Quadrupole mass analyzer, 0105 earth and related environmental sciences, Spectrometer, haze formation, interstellar, Chemistry, photodetachment, Triple quadrupole mass spectrometer, cn, Acetylene, 13. Climate action, atmosphere, symbols, Atomic physics, Titan (rocket family), anions
Abstract: International audience; The reaction of C3N- with acetylene was studied using three different experimental setups, a triple quadrupole mass spectrometer (Trento), a tandem quadrupole mass spectrometer (Prague), and the "CERISES" guided ion beam apparatus at Orsay. The process is of astrophysical interest because it can function as a chain elongation mechanism to produce larger anions that have been detected in Titan's ionosphere by the Cassini Plasma Spectrometer. Three major products of primary processes, C2H-, CN-, and C5N-, have been identified, whereby the production of the cyanide anion is probably partly due to collisional induced dissociation. The formations of all these products show considerable reaction thresholds and also display comparatively small cross sections. Also, no strong signals of anionic products for collision energies lower than 1 eV have been observed. Ab initio calculations have been performed to identify possible pathways leading to the observed products of the title reaction and to elucidate the thermodynamics of these processes. Although the productions of CN- and C5N- are exoergic, all reaction pathways have considerable barriers. Overall, the results of these computations are in agreement with the observed reaction thresholds. Due to the existence of considerable reaction enenrgy barriers and the small observed cross sections, the title reaction is not very likely to play major role in the buildup of large anions in cold environments like the interstellar medium or planetary and satellite ionospheres.
Published: 2016
Full Text: View/download PDF

10. Two-dimensional resonant magnetic soft X-ray scattering set-up for extreme sample environment

Author: Stefan Stanescu, Frederic Merlet, Cristian Mocuta, Antoine Barbier, Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Laboratoire Nano-Magnétisme et Oxydes (LNO), Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Service de Physique et de Chimie des Surfaces et Interfaces (SPCSI), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and We acknowledge the financial support from the RTRA ‘Triangle de la Physique’ under grant number 2010-014T.
Subjects: Diffraction, Nuclear and High Energy Physics, diffraction, Holography, Synchrotron radiation, 01 natural sciences, law.invention, symbols.namesake, Optics, law, magnetic nanostructures, 0103 physical sciences, 010306 general physics, Instrumentation, [PHYS]Physics [physics], 010302 applied physics, Physics, Radiation, business.industry, Small-angle X-ray scattering, Scattering, SAXS, Synchrotron, soft X-ray, Fourier transform, resonant magnetic scattering, symbols, Fourier transform holography, Biological small-angle scattering, business
Abstract: International audience; The newly built MagSAXS (magnetic small-angle X-ray scattering) set-up dedicated to the direct two-dimensional measurement of magnetic scattering using polarized synchrotron radiation in extreme sample environments is presented. Pure optical transport of the image is used to record the magnetic scattering with a two-dimensional CCD visible-light camera. The set-up is able to probe magnetic correlation lengths from the micrometer down to the nanometer scale. A detailed layout is presented along with preliminary results obtained at several beamlines at Synchrotron SOLEIL. The presented examples underline the wide range of possible applications spanning from correlation lengths determination to Fourier transform holography.
Published: 2012
Full Text: View/download PDF

11. Reverse electrochemical etching method for fabricating ultra-sharp platinum/iridium tips for combined scanning tunneling microscope/ atomic force microscope based on a quartz tuning fork

Author: Morán Meza, José Antonio, Polesel Maris, J., Lubin, Christophe, Thoyer, F., Makky, A., Ouerghi, A., Cousty, Jacques, Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Grupo de Materiales Nanoestructurados, Laboratoire de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), 1. Peru’s National Council of Science and Technology (Concytec).2. Réseau Thématique de Recherche Avancée (RTRA-Triangle de la Physique).3. CEA/Direction des Relations Internationales (DRI)., jpoleselmaris@ groupeseb.com, christophe.lubin@cea.fr, francois. thoyer@cea.fr, ali.makky@u-psud.fr, abdelkarim.ouerghi@ lpn.cnrs.fr, and jacques.cousty@cea.fr
Subjects: FowlereNordheim plot, Materials science, Analytical chemistry, STM, General Physics and Astronomy, 02 engineering and technology, 01 natural sciences, Fowler-Nordheim plot, Electrochemical cell, law.invention, Etching (microfabrication), law, 0103 physical sciences, tip etching, General Materials Science, Tuning fork, piezoelectric probe, 010302 applied physics, Tip etching, business.industry, Graphene, Resolution (electron density), graphene, Conductive atomic force microscopy, tuning fork, 021001 nanoscience & nanotechnology, Epitaxial graphene, Field electron emission, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Optoelectronics, Scanning tunneling microscope, AFM, 0210 nano-technology, business
Abstract: International audience; Sharp Pt/Ir tips have been reproducibly etched by an electrochemical process using an inverse geometry of an electrochemical cell and a dedicated electronic device which allows us to control the applied voltages waveform and the intensity of the etching current. Conductive tips with a radius smaller than 10 nm were routinely produced as shown by field emission measurements through FowlereNordheim plots. These etched tips were then fixed on a quartz tuning fork force sensor working in a qPlus configuration to check their performances for both scanning tunneling microscopy (STM) and atomic force microscopy (AFM) imaging. Their sharpness and conductivity are evidenced by the resolution achieved in STM and AFM images obtained of epitaxial graphene on 6H-SiC(0001) surface. The structure of an epitaxial graphene layer thermally grown on the 6H-SiC(0001) (6R3x6R3)R30° reconstructed surface, was successfully imaged at room temperature with STM, dynamic STM and by frequency modulated AFM.
Published: 2015
Full Text: View/download PDF

12. Tip induced mechanical deformation of epitaxial graphene grown on reconstructed 6H-SiC(0001) surface during scanning tunneling and atomic force microscopy studies

Author: François Thoyer, José Antonio Morán Meza, Christophe Lubin, Jacques Cousty, Grupo de Materiales Nanoestructurados, Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and 1. Réseau Thématique de Recherche Avancée (RTRA-Triangle de la Physique)2. CEA/Direction des Relations Internationales (DRI)
Subjects: Materials science, Analytical chemistry, STM, Bioengineering, 02 engineering and technology, mechanical properties, 01 natural sciences, law.invention, law, silicon carbide, Lattice (order), 0103 physical sciences, Monolayer, General Materials Science, Electrical and Electronic Engineering, 010306 general physics, Quantum tunnelling, Condensed matter physics, Mechanical Engineering, General Chemistry, Conductive atomic force microscopy, Dissipation, 021001 nanoscience & nanotechnology, epitaxial graphene, Amplitude, Mechanics of Materials, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Scanning tunneling microscope, AFM, 0210 nano-technology, Excitation
Abstract: International audience; Tip induced mechanical deformation of epitaxial graphene grown on reconstructed 6H–SiC(0001) surface during scanning tunneling and atomic force microscopy studies Abstract The structural and mechanical properties of an epitaxial graphene (EG) monolayer thermally grown on top of a 6H–SiC(0001) surface were studied by combined dynamic scanning tunneling microscopy (STM) and frequency modulation atomic force microscopy (FM-AFM). Experimental STM, dynamic STM and AFM images of EG on 6H–SiC(0001) show a lattice with a 1.9 nm period corresponding to the (6 × 6) quasi-cell of the SiC surface. The corrugation amplitude of this (6 × 6) quasi-cell, measured from AFM topographies, increases with the setpoint value of the frequency shift Δf (15–20 Hz, repulsive interaction). Excitation variations map obtained simultaneously with the AFM topography shows that larger dissipation values are measured in between the topographical bumps of the (6 × 6) quasi-cell. These results demonstrate that the AFM tip deforms the graphene monolayer. During recording in dynamic STM mode, a frequency shift (Δf) map is obtained in which Δf values range from 41 to 47 Hz (repulsive interaction). As a result, we deduced that the STM tip, also, provokes local mechanical distortions of the graphene monolayer. The origin of these tip-induced distortions is discussed in terms of electronic and mechanical properties of EG on 6H–SiC(0001).
Published: 2015
Full Text: View/download PDF

13. Fabricación de puntas de fibra de carbono ultrafinas para investigaciones de microscopía de efecto túnel de grafeno epitaxial sobre la superficie de 6H-SiC(0001)

Author: Morán-Meza, José A., Lubin, Christophe, Thoyer, François, Villegas-Rosales, Kevin A., Gutarra-Espinoza, Abel A., Martin, Frantz, Cousty, Jacques, Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Grupo de Materiales Nanoestructurados, Laboratoire d'Etude de la Corrosion Aqueuse (LECA), Service de la Corrosion et du Comportement des Matériaux dans leur Environnement (SCCME), Département de Physico-Chimie (DPC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Département de Physico-Chimie (DPC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, and 1. Peru’s National Council of Science and Technology (Concytec).2. Réseau Thématique de Recherche Avancée (RTRA-Triangle de la Physique).3. CEA/Direction des Relations Internationales (DRI).
Subjects: [PHYS]Physics [physics], graphene, STM, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], AFM, Fowler-Nordheim plot, carbon fiber
Abstract: International audience; The fabrication of ultra-sharp tips from carbon fiber (CF), which are mounted on a qPlus probe for combined dynamic scanning tunneling microscopy (STM) and frequency modulation atomic force microscopy (FM-AFM) experiments, is reported. The carbon fiber tips were electrochemically etched in a KOH or NaOH solution, using different electronic devices. CF tips with an apex radius ~10 nm, as deduced from the measured slopes of the Fowler–Nordheim plots (kR < 70 nm for k ~ 6), were routinely obtained with a home-made electronic device that controls the intensity of the etching current. Then, these conductive CF tips were also characterized by imaging the 6H-SiC(0001) surface covered by an epitaxial graphene layer in ultra-high vacuum (UHV). The lattice of the (6R3x6R3)R30° reconstruction was regularly imaged by STM working either in non-oscillating mode or in dynamic mode, which also maps the variations of the force gradient. From these measurements with a constant mean-tunneling-current of 20 pA, it was found that the STM tip suffered variations of the tip/surface force gradient in between 8.25 and 16.50 N/m when it scanned the epitaxial graphene layer on the reconstructed 6H-SiC(0001) surface.
Published: 2015
Full Text: View/download PDF

14. Fabricación de puntas de fibra de carbono ultrafinas para investigaciones de microscopía de efecto túnel de grafeno epitaxial sobre la superficie de 6H-SiC(0001)

Author: F. Martin, J.A. Morán Meza, François Thoyer, C. Lubin, J. Cousty, K.A. Villegas Rosales, A.A. Gutarra Espinoza, Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Grupo de Materiales Nanoestructurados, Laboratoire d'Etude de la Corrosion Aqueuse (LECA), Service de la Corrosion et du Comportement des Matériaux dans leur Environnement (SCCME), Département de Physico-Chimie (DPC), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Département de Physico-Chimie (DPC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, 1. Peru’s National Council of Science and Technology (Concytec).2. Réseau Thématique de Recherche Avancée (RTRA-Triangle de la Physique).3. CEA/Direction des Relations Internationales (DRI)., and jacques.cousty@cea.fr
Subjects: Carbon fiber (CF), Surface (mathematics), Fabrication, Materials science, Scanning Tunneling Microscopy (STM), Analytical chemistry, STM, Fowler-Nordheim plot, law.invention, carbon fiber, law, Frequency modulation atomic force microscopy (FM-AFM), General Materials Science, [PHYS]Physics [physics], Graphene, business.industry, Surface force, graphene, General Chemistry, Radius, Conductive atomic force microscopy, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Optoelectronics, Scanning tunneling microscope, AFM, business, Layer (electronics)
Abstract: International audience; The fabrication of ultra-sharp tips from carbon fiber (CF), which are mounted on a qPlus probe for combined dynamic scanning tunneling microscopy (STM) and frequency modulation atomic force microscopy (FM-AFM) experiments, is reported. The carbon fiber tips were electrochemically etched in a KOH or NaOH solution, using different electronic devices. CF tips with an apex radius ~10 nm, as deduced from the measured slopes of the Fowler–Nordheim plots (kR < 70 nm for k ~ 6), were routinely obtained with a home-made electronic device that controls the intensity of the etching current. Then, these conductive CF tips were also characterized by imaging the 6H-SiC(0001) surface covered by an epitaxial graphene layer in ultra-high vacuum (UHV). The lattice of the (6R3x6R3)R30° reconstruction was regularly imaged by STM working either in non-oscillating mode or in dynamic mode, which also maps the variations of the force gradient. From these measurements with a constant mean-tunneling-current of 20 pA, it was found that the STM tip suffered variations of the tip/surface force gradient in between 8.25 and 16.50 N/m when it scanned the epitaxial graphene layer on the reconstructed 6H-SiC(0001) surface.
Published: 2015
Full Text: View/download PDF

15. Improvement of the thermal properties of optically pumped semiconductor chips at 850 nm (orale)

Author: Gozhyk, Iryna, Beaudoin, Grégoire, Janicot, Sylvie, Lafosse, Xavier, Dumont, Paul, Garnache, Arnaud, Georges, Patrick, Lucas-Leclin, Gaëlle, Sagnes, Isabelle, Laboratoire de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), Laboratoire Charles Fabry / Lasers, Laboratoire Charles Fabry (LCF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS), Institut d’Electronique et des Systèmes (IES), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Térahertz, hyperfréquence et optique (TéHO), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), and RTRA - Triangle de la Physique RENATECH
Subjects: [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Astrophysics::High Energy Astrophysical Phenomena
Abstract: Thermal saturation of VECSELs emission properties stays a major issue in those applications, requiring a high precision on the chip emission wavelength (such as atomic clocks experiments). In this paper we analyze the possibility to reduce the thermal resistance of the semiconductor chip emitting at 850nm by means of substrate substitution method. We propose two different techniques and compare their efficiency through experimental study on VECSEL emission properties.
Published: 2014

16. Measurement of the intrinsic damping constant in individual nanodisks of Y3Fe5O12 and Y3Fe5O 12|Pt

Author: P. Bortolotti, R. Bernard, Paris Sud, Eric Jacquet, Russian Federation, O. Klein, Abdelmadjid Anane, Christian Hahn, Cnrs Ura, G. de Loubens, M. Mu, Etat Condens, Vicent Cros, Cea Saclay, Laboratoire Nano-Magnétisme et Oxydes (LNO), Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Unité mixte de physique CNRS/Thales (UMPhy CNRS/THALES), THALES-Centre National de la Recherche Scientifique (CNRS), Instituto de Sistemas Optoelectrónicos y Microtecnología, Universidad Politécnica de Madrid (UPM), French Grants Trinidad (ASTRID 2012 program)RTRA Triangle de la Physique grant Spinoscopy, and THALES [France]-Centre National de la Recherche Scientifique (CNRS)
Subjects: [PHYS]Physics [physics], Telecomunicaciones, Materials science, Nanostructure, Microscope, Physics and Astronomy (miscellaneous), Condensed matter physics, Yttrium iron garnet, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Ferromagnetic resonance, law.invention, Pulsed laser deposition, Laser linewidth, chemistry.chemical_compound, chemistry, law, 0103 physical sciences, Electrónica, Damping constant, 010306 general physics, 0210 nano-technology, Homogeneous broadening
Abstract: Hahn, C. et al., We report on an experimental study on the spin-waves relaxation rate in two series of nanodisks of diameter ¿=300 , 500, and 700¿nm, patterned out of two systems: a 20¿nm thick yttrium iron garnet (YIG) film grown by pulsed laser deposition either bare or covered by 13¿nm of Pt. Using a magnetic resonance force microscope, we measure precisely the ferromagnetic resonance linewidth of each individual YIG and YIG|Pt nanodisks. We find that the linewidth in the nanostructure is sensibly smaller than the one measured in the extended film. Analysis of the frequency dependence of the spectral linewidth indicates that the improvement is principally due to the suppression of the inhomogeneous part of the broadening due to geometrical confinement, suggesting that only the homogeneous broadening contributes to the linewidth of the nanostructure. For the bare YIG nano-disks, the broadening is associated to a damping constant ¿=4¿×¿10¿4 . A threefold increase of the linewidth is observed for the series with Pt cap layer, attributed to the spin pumping effect. The measured enhancement allows to extract the spin mixing conductance found to be G¿¿¿¿=1.55¿×¿1014¿¿¿1¿m¿2 for our YIG(20nm)|Pt interface, thus opening large opportunities for the design of YIG based nanostructures with optimized magnetic losses., This research was supported by the French Grants Trinidad (ASTRID 2012 program) and by the RTRA Triangle de la Physique grant Spinoscopy.
Published: 2014
Full Text: View/download PDF

17. Two-cross-polarized-frequency VECSEL at 852nm for CPT-based Cs clocks (poster)

Author: Camargo, Fabiola, Dumont, Paul, Ghozyk, Iryna, Lucas-Leclin, Gaëlle, Georges, Patrick, Danet, Jean-Marie, Holleville, David, Guerandel, Stéphane, Sagnes, Isabelle, Baili, Ghaya, Morvan, Loic, Pillet, Gregoire, Dolfi, Daniel, Laboratoire Charles Fabry / Lasers, Laboratoire Charles Fabry (LCF), Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS), 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 de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), Thales Research and Technology [Palaiseau], THALES [France], RENATECH, RTRA/Triangle de la Physique (2010-089T), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS), and THALES
Subjects: Condensed Matter::Quantum Gases, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Fluctuations relaxations and noise, Vertical cavity surface emitting lasers, Physics::Optics, 140.7260,270.2500, Physics::Atomic Physics
Abstract: International audience; We demonstrate a tunable high-purity microwave signal generation from a cross- polarized dual-frequency diode-pumped vertical external-cavity semiconductor laser operating at 852 nm for the coherent population trapping of cesium atoms in compact atomic frequency references.
Published: 2013

18. Wavefront improvement in an injection-seeded soft x-ray laser based on a solid-target plasma amplifier

Author: Lu Li, Stéphane Sebban, T. T. T. Le, Yong Wang, Bitao Hu, Gilles Maynard, S. Daboussi, David Ros, Liang Yin, Eduardo Oliva, Shoujun Wang, Jorge J. Rocca, Philippe Zeitoun, Laboratoire d'optique appliquée (LOA), École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Lanzhou Univ, Sch Nucl Sci & Technol, Lanzhou 730000, Peoples R China, NSF Engineering Research Center for Extreme Ultraviolet Science and Technology, Colorado State University [Fort Collins] (CSU), Laboratoire de physique des gaz et des plasmas (LPGP), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), AMOS program of the Office of Basic Energy Science, US Department of EnergyNSF ERC for Extreme Ultraviolet Science and Technology with equipment development under NSF MRI-ARRA 09-561SHYLAX, RTRA 'Triangle de la Physique,' INREX in LASERLAB3 and FP7 European program 284464, and European Project: 284464,LAERLAB3
Subjects: Brightness, genetic structures, Astrophysics::High Energy Astrophysical Phenomena, Physics::Optics, BEAM, Lambda, 01 natural sciences, NM, law.invention, 010309 optics, Root mean square, COHERENT, Optics, law, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], 0103 physical sciences, 010306 general physics, Wavefront, Physics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], business.industry, Amplifier, Astrophysics::Instrumentation and Methods for Astrophysics, AMPLIFICATION, Wavefront sensor, Plasma, Laser, Atomic and Molecular Physics, and Optics, eye diseases, Optoelectronics, sense organs, business
Abstract: International audience; The wavefront of an injection-seeded soft x-ray laser beam generated by amplification of high-harmonic pulses in a lambda = 18.9 nm molybdenum plasma amplifier was measured by a Hartmann wavefront sensor with an accuracy of lambda/32 root mean square (rms). A significant improvement in wavefront aberrations of 0.51 +/- 0.03 lambda rms to 0.23 +/- 0.01 lambda rms was observed as a function of plasma column length. The variation of wavefront characteristic as a function time delay between the injection of the seed and peak of soft x-ray amplifier pump was studied. The measurements were used to reconstruct the soft x-ray source and confirm its high peak brightness. (C) 2013 Optical Society of America
Published: 2013
Full Text: View/download PDF

19. X-ray Chirped Pulse Amplification: towards GW Soft X-ray Lasers

Author: Thi Thu Thuy Le, Marta Fajardo, Philippe Zeitoun, Lu Li, Pedro Velarde, David Ros, Stéphane Sebban, Eduardo Oliva, Laboratoire d'optique appliquée (LOA), École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de physique des gaz et des plasmas (LPGP), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Instituto de Fusión Nuclear, Universidad Politécnica de Madrid (UPM), Inst Super Tecn, GoLP Inst Plasmas & Fusao Nucl, and SHYLAX project from RTRA-Triangle de la Physique
Subjects: Chirped pulse amplification, chirped pulse amplification, 7. Clean energy, 01 natural sciences, lcsh:Technology, law.invention, 010309 optics, X-ray laser, lcsh:Chemistry, Optics, law, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], 0103 physical sciences, High harmonic generation, General Materials Science, 010306 general physics, Instrumentation, Collisional excitation, lcsh:QH301-705.5, plasma, Fluid Flow and Transfer Processes, Physics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], business.industry, lcsh:T, Process Chemistry and Technology, General Engineering, modeling, Plasma, Nanosecond, Laser, lcsh:QC1-999, high harmonic generation, Computer Science Applications, Pulse (physics), lcsh:Biology (General), lcsh:QD1-999, lcsh:TA1-2040, business, lcsh:Engineering (General). Civil engineering (General), lcsh:Physics
Abstract: International audience; Extensive modeling of the seeding of plasma-based soft X-ray lasers is reported in this article. Seminal experiments on amplification in plasmas created from solids have been studied in detail and explained. Using a transient collisional excitation scheme, we show that a 18 mu J, 80 fs fully coherent pulse is achievable by using plasmas pumped by a compact 10 Hz laser. We demonstrate that direct seeding of plasmas created by nanosecond lasers is not efficient. Therefore, we propose and fully study the transposition to soft X-rays of the Chirped Pulse Amplification (CPA) technique. Soft X-ray pulses with energy of 6 mJ and 200 fs duration are reachable by seeding plasmas pumped by compact 100 J, sub-ns, 1 shot/min lasers. These soft X-ray lasers would reach GW power, corresponding to an increase of 100 times as compared to the highest peak power achievable nowadays in the soft X-ray region (30 eV-1 keV). X-ray CPA is opening new horizon for soft x-ray ultra-intense sources.
Published: 2013
Full Text: View/download PDF

20. Direct observation of electron thermalization and electron-phonon coupling in photoexcited bismuth

Author: E. Papalazarou, Luca Perfetti, Yoshiyuki Ohtsubo, J. Mauchain, Marino Marsi, Davide Boschetto, B. Arnaud, Nathalie Vast, Iurii Timrov, Jérôme Faure, Laboratoire d'optique appliquée (LOA), École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des Solides (LPS), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Laboratoire des Solides Irradiés (LSI), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X), CASSIOPEE, Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), RTRA Triangle de la Physique, EU/FP7 under the contract Go Fast, Grant No. 280555, European Research Council under Contract No. 306708, Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), and Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Condensed Matter - Materials Science, Photoemission spectroscopy, chemistry.chemical_element, Materials Science (cond-mat.mtrl-sci), FOS: Physical sciences, 02 engineering and technology, Electron, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Electronic, Optical and Magnetic Materials, Bismuth, chemistry, Ab initio quantum chemistry methods, 0103 physical sciences, Quasiparticle, Atomic physics, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], 010306 general physics, 0210 nano-technology, Fermi gas, Surface states, Bloch wave
Abstract: International audience; We investigate the ultrafast response of the bismuth (111) surface by means of time resolved photoemission spectroscopy. The direct visualization of the electronic structure allows us to gain insights on electron-electron and electron-phonon interaction. Concerning electron-electron interaction , it is found that electron thermalization is fluence dependent and can take as much as several hundreds of femtoseconds at low fluences. This behavior is in qualitative agreement with Landau's theory of Fermi liquids but the data show deviations from the behavior of a common 3D degenerate electron gas. Concerning electron-phonon interaction, our data allows us to directly observe the coupling of individual Bloch state to the coherent A1g mode. It is found that surface states are much less coupled to this mode when compared to bulk states. This is confirmed by ab initio calculations of surface and bulk bismuth.
Published: 2013
Full Text: View/download PDF

21. Gestion de la thermique dans les structures actives des lasers vecsels à 850 NM (Orale)

Author: Gozhyk, Iryna, Beaudoin, Grégoire, Sagnes, Isabelle, Garnache, Arnaud, Janicot, Sylvie, Georges, Patrick, Lucas-Leclin, Gaëlle, Laboratoire Charles Fabry / Lasers, Laboratoire Charles Fabry (LCF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS), Laboratoire de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), Institut d’Electronique et des Systèmes (IES), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Térahertz, hyperfréquence et optique (TéHO), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), RTRA/Triangle de la Physique, and RENATECH
Subjects: laser à semiconducteur, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], VECSEL, résistance thermique
Abstract: National audience; L'échauffement des structures actives semiconductrices dans les lasers VECSELs constitue une forte limitation à l'émission de puissances élevées. Nous évaluons théoriquement et expérimentalement les effets thermiques dans ces composants, et mettons en œuvre une technologie de report sur substrat Au développée pour améliorer leur résistance thermique.
Published: 2013

22. Emission bifréquence d'un laser à semiconducteur en cavité externe à 852 nm pour les horloges atomiques a césium (orale)

Author: Camargo, Fabiola, Dumont, Paul, Lucas-Leclin, Gaëlle, Georges, Patrick, Danet, Jean-Marie, Holleville, David, Guérandel, S., Sagnes, Isabelle, Baili, Ghaya, Morvan, Loïc, Dolfi, Daniel, Laboratoire Charles Fabry / Lasers, Laboratoire Charles Fabry (LCF), Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS), 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 de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), Thales Research and Technology [Palaiseau], THALES, RTRA Triangle de la Physique, réseau RENATECH, and THALES [France]
Subjects: laser à semiconducteur, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], VECSEL, horloges atomiques
Abstract: National audience; Nous décrivons l'émission simultanée en phase, sur deux fréquences optiques polarisées perpendiculairement, d'un laser à semiconducteur en cavité externe pompé optiquement. L'émission est accordable autour de la raie D2 du césium à 852,14 nm avec une puissance optique d'environ 13 mW sur chaque polarisation. La différence de fréquence est ajustée grâce à un modulateur électro-optique autour de 9,2 GHz. Nous évaluons la source réalisée en vue de son application au piégeage cohérent de population d'atomes de césium dans une horloge atomique.
Published: 2013

23. Grazing incidence x-ray diffraction for the study of polycrystalline layers

Author: Dominique Gosset, Jean-François Berar, Sophie Le Caër, David Simeone, Gianguido Baldinozzi, Laboratoire Structures, Propriétés et Modélisation des solides (SPMS), Institut de Chimie du CNRS (INC)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Analyse Microstructurale des Matériaux (LA2M), Service des Recherches Métallurgiques Appliquées (SRMA), Département des Matériaux pour le Nucléaire (DMN), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Département des Matériaux pour le Nucléaire (DMN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de Radiolyse (LCF) (LRad), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), CRG et Grands Instruments (CRG), Institut Néel (NEEL), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF), RTRA Triangle de la Physique, projet 2011-074T, INSTRUMAT, CRG & Grands instruments (NEEL - CRG), and Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)
Subjects: Diffraction, Materials science, 02 engineering and technology, Substrate (electronics), 01 natural sciences, Optics, 0103 physical sciences, Materials Chemistry, Thin film, 010302 applied physics, Total internal reflection, Condensed matter physics, business.industry, Scattering, Metals and Alloys, Surfaces and Interfaces, 021001 nanoscience & nanotechnology, Microstructure, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, X-ray crystallography, biological sciences, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Crystallite, 0210 nano-technology, business
Abstract: International audience; Different diffraction patterns measured above and below the critical angle for total reflection were recorded on a Gd doped ceria layer deposited on a Si(100) substrate in asymmetric coplanar diffraction conditions. From the analysis of diffraction patterns, it was possible to point out peculiar optical aberrations responsible for the shifts and the broadenings of Bragg peaks induced by this setup. Corrections for all these aberrations were implanted in a Rietveld programme. Using these corrections, it becomes possible to follow the evolution of the structure (chemical composition, phases) and the micro structure (strain field, micro strain due to heterogeneities between grains, size of coherent diffracting domains) versus the depth on thin films.
Published: 2013
Full Text: View/download PDF

24. A preferred orientation correction to describe a fiber texture under glancing incidence

Author: Dominique Gosset, David Simeone, Gianguido Baldinozzi, Laboratoire Structures, Propriétés et Modélisation des solides (SPMS), Institut de Chimie du CNRS (INC)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Analyse Microstructurale des Matériaux (LA2M), Service des Recherches Métallurgiques Appliquées (SRMA), Département des Matériaux pour le Nucléaire (DMN), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Département des Matériaux pour le Nucléaire (DMN), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, and RTRA Triangle de la physique, projet 2011-074T, INSTRUMAT. C'nano Ile-de-France, projet SolNac (2009)
Subjects: Diffraction, Materials science, Scattering, business.industry, Physics::Optics, 02 engineering and technology, 021001 nanoscience & nanotechnology, 010403 inorganic & nuclear chemistry, 01 natural sciences, General Biochemistry, Genetics and Molecular Biology, 0104 chemical sciences, Characterization (materials science), Optics, Perpendicular, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Texture (crystalline), Fiber, Thin film, 0210 nano-technology, business, Incidence (geometry)
Abstract: International audience; Much work is nowadays being devoted to the characterization of the structure and the microstructure of thin films and mesoporous materials. Different physical and chemical processes used to elaborate these thin films often induce a fiber texture in these materials. The X-ray glancing-incidence technique appears to be a useful tool for collecting diffraction patterns of thin films while avoiding the peaks of the substrate. However, the scattering vector in this asymmetric scattering geometry is not perpendicular to the surface of the sample. This point implies that the correction developed to model the effects of a fiber texture in Bragg-Brentano geometry, where the scattering vector is always normal to the surface of the sample, cannot be applied in glancing incidence. This work presents a procedure to correct the preferred orientation due to this fiber texture in asymmetric scattering geometry and then in glancing incidence. By an example, it is proved that this correction of the fiber texture is efficient. The main point of interest regarding this correction is that only a few parameters are needed to handle the effect of the fiber texture on the diffraction patterns collected in asymmetric scattering geometry and then under glancing incidence.
Published: 2013
Full Text: View/download PDF

25. X-ray holographic imaging of magnetic order in patterned Co/Pd multilayers

Author: Renaud Delaunay, Maurizio Sacchi, Carlo Spezzani, Horia Popescu, Franck Fortuna, Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), RTRA Triangle de la physique [2009-082T FibNanoSynth], and CNRS, within the PEPS_SASLELX program
Subjects: 010302 applied physics, Physics, Magnetic order, business.industry, X-ray, Holographic imaging, 02 engineering and technology, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Electronic, Optical and Magnetic Materials, Optics, 0103 physical sciences, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], 0210 nano-technology, business
Abstract: International audience; We address the role of lateral confinement in determining the micromagnetic structure of small objects featuring perpendicular magnetic anisotropy. We have imaged the spatial distribution of magnetic domains in Co/Pd multilayered objects by x-ray holography in transmission mode, a technique based on resonant coherent scattering of polarized x rays. In addition to high spatial resolution and magnetic sensitivity, x-ray holography features chemical selectivity and probes the entire bulk of the magnetic sample. By analyzing and comparing images of several magnetic objects (squares and rectangles with 0.4-3-mu m lateral sizes) that underwent the same preparation procedure and magnetic history, we highlight the influence of the object shape and of its orientation with respect to an external field in determining the remanent magnetic microstructure. The discussion of our results is backed by micromagnetic calculations.
Published: 2013
Full Text: View/download PDF

26. Improvement of the thermal properties of semiconductor chips at 850 nm (poster)

Author: Gozhyk, Iryna, Beaudoin, Grégoire, Janicot, Sylvie, Lafosse, Xavier, Garnache, Arnaud, Sagnes, Isabelle, Georges, Patrick, Lucas-Leclin, Gaëlle, Laboratoire Charles Fabry / Lasers, Laboratoire Charles Fabry (LCF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS), Laboratoire de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), Institut d’Electronique et des Systèmes (IES), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Térahertz, hyperfréquence et optique (TéHO), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), and RTRA/Triangle de la Physique RENATECH
Subjects: [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2013

27. Intracellular fate of carbon nanotubes inside murine macrophages: pH-dependent detachment of iron catalyst nanoparticles

Author: Julien Cambedouzou, Mathieu Pinault, Cyrill Bussy, Mickaël Huard, C. Mory, Sophie Lanone, Murielle Salomé, Jorge Boczkowski, Esther Belade, Pascale Launois, Barbara Fayard, Nathalie Brun, Erwan Paineau, Lucie Armand, INSERM U955, équipe 4, Laboratoire de Physique des Solides (LPS), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Nanomedicine laboratory, University College of London [London] (UCL)-Centre for Drug Delivery Research-UCL School of Pharmacy-University College of London [London] (UCL)-Centre for Drug Delivery Research-UCL School of Pharmacy-Institut Mondor de Recherche Biomédicale (IMRB), Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR10-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR10-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Institut de Chimie Séparative de Marcoule (ICSM - UMR 5257), Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), X-ray Imaging Group, European Synchrotron Radiation Facility (ESRF), Laboratoire Francis PERRIN (LFP - URA 2453), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut Mondor de Recherche Biomédicale (IMRB), Institut National de la Santé et de la Recherche Médicale (INSERM)-IFR10-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), Service de Physiologie Explorations Fonctionnelles, Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Hôpital Henri Mondor-Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Hôpital Henri Mondor-Service de pneumologie et pathologie professionnelle, Centre Hospitalier Intercommunal de Créteil (CHIC)-Centre Hospitalier Intercommunal de Créteil (CHIC)-Institut Mondor de Recherche Biomédicale (IMRB), Service de pneumologie et pathologie professionnelle, CB and EP respectively acknowledge C'Nano Ile de France and RTRA 'Triangle de la Physique' for financial support of their fellowships. C'Nano-IdF is the nanoscience competence center of Paris Region, supported by CNRS, CEA, MESR, and Région Ile-de-France., BMC, Ed., Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Nanomedicine laboratory, Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Ecole Nationale Supérieure de Chimie de Montpellier (ENSCM)-Institut de Chimie du CNRS (INC)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, Health, Toxicology and Mutagenesis, Carbon nanotubes, Metal Nanoparticles, Nanoparticle, Nanotechnology, Spectroscopy, Electron Energy-Loss, 02 engineering and technology, Carbon nanotube, Toxicology, Cathepsin B, Cell Line, law.invention, Nanomaterials, Catalysis, Mice, 03 medical and health sciences, Degradation, Microscopy, Electron, Transmission, X-Ray Diffraction, law, Animals, 030304 developmental biology, 0303 health sciences, Toxicity, Nanotubes, Carbon, Research, Macrophages, Electron energy loss spectroscopy, Lysosome-Associated Membrane Glycoproteins, Spectrometry, X-Ray Emission, General Medicine, Hydrogen-Ion Concentration, 021001 nanoscience & nanotechnology, Fluorescence, Lysosome acidification, Iron catalyst nanoparticles, Transmission electron microscopy, [SDV.SPEE] Life Sciences [q-bio]/Santé publique et épidémiologie, Biophysics, [SDV.SPEE]Life Sciences [q-bio]/Santé publique et épidémiologie, Macrolides, Lysosomes, 0210 nano-technology, Iron Compounds, Synchrotrons, Intracellular
Abstract: Background Carbon nanotubes (CNT) are a family of materials featuring a large range of length, diameter, numbers of walls and, quite often metallic impurities coming from the catalyst used for their synthesis. They exhibit unique physical properties, which have already led to an extensive development of CNT for numerous applications. Because of this development and the resulting potential increase of human exposure, an important body of literature has been published with the aim to evaluate the health impact of CNT. However, despite evidences of uptake and long-term persistence of CNT within macrophages and the central role of those cells in the CNT-induced pulmonary inflammatory response, a limited amount of data is available so far on the CNT fate inside macrophages. Therefore, the overall aim of our study was to investigate the fate of pristine single walled CNT (SWCNT) after their internalization by macrophages. Methods To achieve our aim, we used a broad range of techniques that aimed at getting a comprehensive characterization of the SWCNT and their catalyst residues before and after exposure of murine macrophages: X-ray diffraction (XRD), High Resolution (HR) Transmission Electron Microscopy (TEM), High Angle Annular Dark Field-Scanning TEM (HAADF-STEM) coupled to Electron Energy Loss Spectroscopy (EELS), as well as micro-X-ray fluorescence mapping (μXRF), using synchrotron radiation. Results We showed 1) the rapid detachment of part of the iron nanoparticles initially attached to SWCNT which appeared as free iron nanoparticles in the cytoplasm and nucleus of CNT-exposed murine macrophages, and 2) that blockade of intracellular lysosomal acidification prevented iron nanoparticles detachment from CNT bundles and protected cells from CNT downstream toxicity. Conclusions The present results, while obtained with pristine SWCNT, could likely be extended to other catalyst-containing nanomaterials and surely open new ways in the interpretation and understanding of CNT toxicity.
Published: 2013
Full Text: View/download PDF

28. Dual frequency emission in a compact semiconductor laser for coherent population trapping cesium atomic clocks

Author: Camargo, Fabiola, Georges, Patrick, Lucas-Leclin, Gaëlle, Girard, Nils, Baili, Ghaya, Morvan, Loïc, Dolfi, Daniel, Holleville, David, Guérandel, S., Sagnes, Isabelle, Laboratoire Charles Fabry / Lasers, Laboratoire Charles Fabry (LCF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS), Thales Research and Technology [Palaiseau], THALES, 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 de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), RTRA/Triangle de la Physique (2010-089T), Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS), and THALES [France]
Subjects: [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Physics::Optics, Physics::Atomic Physics
Abstract: We present the dual-frequency emission of a diode-pumped vertical external-cavity semiconductor laser at 852 nm dedicated to coherent population trapping experiments. With a compact cavity more than 10mW is demonstrated in each polarization, with a frequency difference in the GHz range. One polarization has been stabilized on an atomic transition
Published: 2012

29. Coherent Dual-Frequency Emission of a Vertical External-Cavity Semiconductor Laser at the Cesium D_{2} Line

Author: David Holleville, Fabiola Camargo, Gaëlle Lucas-Leclin, Isabelle Sagnes, J. Barrientos, Loic Morvan, Stéphane Guérandel, Daniel Dolfi, Ghaya Baili, Patrick Georges, 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 Charles Fabry / Lasers, Laboratoire Charles Fabry (LCF), Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS), Thales Research and Technology [Palaiseau], THALES [France], Laboratoire de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), RTRA/Triangle de la Physique (2010-089T), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS), and THALES
Subjects: Materials science, Population, Physics::Optics, semiconductor lasers, 02 engineering and technology, Trapping, 7. Clean energy, 01 natural sciences, Semiconductor laser theory, law.invention, 010309 optics, Optical pumping, 020210 optoelectronics & photonics, Optics, law, 0103 physical sciences, vertical cavity surface emitting lasers, 0202 electrical engineering, electronic engineering, information engineering, Physics::Atomic Physics, Electrical and Electronic Engineering, Maser, education, ComputingMilieux_MISCELLANEOUS, Line (formation), [PHYS]Physics [physics], [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], education.field_of_study, business.industry, Laser, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials, metrology, Semiconductor, Optoelectronics, business, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: International audience; We describe the dual-frequency and dual-polarization emission of a diode-pumped vertical external-cavity semiconductor laser at 852 nm dedicated to the coherent population trapping of cesium atoms. The output power reaches ∼20 mW on each frequency, with a frequency difference in the GHz range.
Published: 2012
Full Text: View/download PDF

30. Coherent phonon coupling to individual Bloch states in photoexcited bismuth

Author: Marino Marsi, J. Mauchain, Jérôme Faure, Luca Perfetti, E. Papalazarou, B. Arnaud, Igor Reshetnyak, Iurii Timrov, Nathalie Vast, A. van Roekeghem, A. Taleb-Ibrahimi, Laboratoire de Physique des Solides (LPS), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Solides Irradiés (LSI), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'optique appliquée (LOA), École Nationale Supérieure de Techniques Avancées (ENSTA Paris)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Institut de Physique de Rennes (IPR), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), RTRA Triangle de la Physique, Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, CASSIOPEE, Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X), Université de Rennes 1 (UR1), and Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Phonon, [PHYS.PHYS.PHYS-ACC-PH]Physics [physics]/Physics [physics]/Accelerator Physics [physics.acc-ph], Binding energy, General Physics and Astronomy, chemistry.chemical_element, FOS: Physical sciences, 02 engineering and technology, 01 natural sciences, Bismuth, Condensed Matter::Materials Science, X-ray photoelectron spectroscopy, Ab initio quantum chemistry methods, [PHYS.PHYS.PHYS-PLASM-PH]Physics [physics]/Physics [physics]/Plasma Physics [physics.plasm-ph], 0103 physical sciences, Wave vector, 010306 general physics, 73.20.Mf, 71.15.Mb, 73.20.At, 78.47.jb, Surface states, Physics, [PHYS]Physics [physics], Condensed Matter - Materials Science, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Condensed matter physics, Materials Science (cond-mat.mtrl-sci), 021001 nanoscience & nanotechnology, Condensed Matter - Other Condensed Matter, [SDV.BBM.BP]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Biophysics, chemistry, Quasiparticle, Atomic physics, 0210 nano-technology, Other Condensed Matter (cond-mat.other)
Abstract: International audience; We investigate the temporal evolution of the electronic states at the bismuth (111) surface by means of time- and angle-resolved photoelectron spectroscopy. The binding energy of bulklike bands oscillates with the frequency of the A(1g) phonon mode, whereas surface states are insensitive to the coherent displacement of the lattice. A strong dependence of the oscillation amplitude on the electronic wave vector is correctly reproduced by ab initio calculations of electron-phonon coupling. Besides these oscillations, all the electronic states also display a photoinduced shift towards higher binding energy whose dynamics follows the evolution of the electronic temperature.
Published: 2012
Full Text: View/download PDF

31. Microcavity-quality-factor enhancement using nonlinear effects close to the bistability threshold and coherent population oscillations

Author: P. Grinberg, Alejandro M. Yacomotti, Yannick Dumeige, Juan Ariel Levenson, E. Le Cren, Kamel Bencheikh, Fonctions Optiques pour les Technologies de l'informatiON ( FOTON ), Université de Rennes 1 ( UR1 ), Université de Rennes ( UNIV-RENNES ) -Université de Rennes ( UNIV-RENNES ) -Université européenne de Bretagne ( UEB ) -Institut National des Sciences Appliquées - Rennes ( INSA Rennes ) -École Nationale Supérieure des Sciences Appliquées et de Technologie ( ENSSAT ) -Télécom Bretagne-Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de photonique et de nanostructures ( LPN ), Centre National de la Recherche Scientifique ( CNRS ), RTRA Triangle de la physique, C'nano IdF, ANR-10-BLAN-1002,CALIN,Cavités à fort facteur de qualité, guides à modes lents et Lumière lente par Interaction Non linéaire ( 2010 ), Optical resonators and their applications, ORA, ANR2010BLAN0312,Optical resonators and their applications, ORA, ANR2010BLAN0312, Fonctions Optiques pour les Technologies de l'informatiON (FOTON), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Université européenne de Bretagne - European University of Brittany (UEB)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-École Nationale Supérieure des Sciences Appliquées et de Technologie (ENSSAT)-Télécom Bretagne-Centre National de la Recherche Scientifique (CNRS), Laboratoire de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), ANR-10-BLAN-1002,CALIN,Cavités à fort facteur de qualité, guides à modes lents et Lumière lente par Interaction Non linéaire(2010), ANR-10-BLAN-0312,ORA,Résonateurs optiques et leurs applications(2010), Université de Rennes (UR)-Université européenne de Bretagne - European University of Brittany (UEB)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), and Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-École Nationale Supérieure des Sciences Appliquées et de Technologie (ENSSAT)-Télécom Bretagne-Centre National de la Recherche Scientifique (CNRS)
Subjects: Bistability, Cavity lifetime, Population, Physics::Optics, 01 natural sciences, Transfer function, law.invention, 010309 optics, Resonator, PACS: 42.65.Pc, 42.55.Sa, 42.50.Gy, Optics, Quality (physics), law, 0103 physical sciences, Dispersion (optics), 010306 general physics, education, Physics, education.field_of_study, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], [ PHYS.PHYS.PHYS-OPTICS ] Physics [physics]/Physics [physics]/Optics [physics.optics], business.industry, food and beverages, Optical microcavity, Atomic and Molecular Physics, and Optics, Nonlinear system, Optoelectronics, Population Oscillations, business, Microcavity
Abstract: 9 pages; International audience; We analytically show that inserting a driven, two-level system inside a microcavity can improve its optical properties. In this approach, the strong dispersion induced by a pump via population oscillations increases the cavity lifetime experienced by a slightly detuned probe. We further predict that if the cavity is pumped through a resonant channel, optical absorptive or dispersive bistability can be combined with the population-oscillation-induced steep material dispersion to obtain a strong quality-factor enhancement. Moreover, differential amplification coming from the nonlinear feature of the pump transfer function can be used to drastically increase the probe transmission beyond intrinsic characteristics of the resonator. The Q-factor enhancement and the differential amplification can be advantageously combined with a frequency pulling effect to stabilize or readjust the microcavity resonance frequency.
Published: 2012
Full Text: View/download PDF

32. Stokes flow paths separation and recirculation cells in X-junctions of varying angle

Author: Jean-Pierre Hulin, J. M. Gomba, M. Cachile, Harold Auradou, Laurent Talon, Grupo de Medios Porosos [Buenos Aires] (GMP), Facultad de Ingeniería [Buenos Aires] (FIUBA), Universidad de Buenos Aires [Buenos Aires] (UBA)-Universidad de Buenos Aires [Buenos Aires] (UBA), Fluides, automatique, systèmes thermiques (FAST), Université Paris-Sud - Paris 11 (UP11)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Instituto de Física Arroyo Seco [Tandil] (IFAS), Facultad de Ciencias Exactas [Tandil], Universidad Nacional del Centro de la Provincia de Buenos Aires [Buenos Aires] (UNICEN)-Universidad Nacional del Centro de la Provincia de Buenos Aires [Buenos Aires] (UNICEN), RTRA 'Triangle de la Physique', and LIA PMF-FMF (Franco-Argentinian International Associated Laboratory in the Physics and Mechanics of Fluids).
Subjects: [PHYS.PHYS.PHYS-FLU-DYN]Physics [physics]/Physics [physics]/Fluid Dynamics [physics.flu-dyn], Ciencias Físicas, Computational Mechanics, FOS: Physical sciences, finite element analysis, Otras Ciencias Físicas, Curvature, 01 natural sciences, Channel Flow, 010305 fluids & plasmas, purl.org/becyt/ford/1 [https], Physics::Fluid Dynamics, 0103 physical sciences, Streamlines, streaklines, and pathlines, 010306 general physics, Dyes, Fluid Flow and Transfer Processes, Physics, Mechanical Engineering, Fluid Dynamics (physics.flu-dyn), Physics - Fluid Dynamics, purl.org/becyt/ford/1.3 [https], Mechanics, Dissipation, Stokes flow, Condensed Matter Physics, Finite element method, Volumetric flow rate, Flow (mathematics), Mechanics of Materials, Planar laser-induced fluorescence, flow simulation, CIENCIAS NATURALES Y EXACTAS
Abstract: Fluid and solute transfer in X-junctions between straight channels is shown to depend critically on the junction angle α in the Stokes flow regime. Experimentally, water and a water-dye solution are injected at equal flow rates in two facing channels of the junction. Planar laser induced fluorescence (PLIF) measurements show that the largest part of each injected fluid "bounces back" preferentially into the outlet channel at the lowest angle to the injection; this is opposite to the inertial case and requires a high curvature of the corresponding streamlines. The proportion of this fluid in the other channel decreases from 50% at α = 90° to 0% at a threshold angle. These counterintuitive features reflect the minimization of energy dissipation for Stokes flows. Finite elements numerical simulations of a 2D Stokes flow of equivalent geometry confirm these results and show that, below the threshold angle αc = 33.8°, recirculation cells are present in the center part of the junction and separate the two injected flows of the two solutions. Reducing further α leads to the appearance of new recirculation cells with lower flow velocities. Fil: Cachile, Mario Andres. Universidad de Buenos Aires. Facultad de Ingeniería. Departamento de Física. Grupo de Medios Porosos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Talon, L.. Universite de Paris Xi. Laboratoire Automatiques et Systeme Thermiques; Francia Fil: Gomba, Juan Manuel. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ciencias Exactas. Instituto de Fisica Arroyo Seco; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Hulin, J.P.. Universite de Paris Xi. Laboratoire Automatiques et Systeme Thermiques; Francia Fil: Auradou, H.. Universite de Paris Xi. Laboratoire Automatiques et Systeme Thermiques; Francia
Published: 2012
Full Text: View/download PDF

33. Evaluation of the single-frequency operation of a short vertical external-cavity semiconductor laser at 852 nm

Author: Isabelle Sagnes, Arnaud Garnache, Fabiola Camargo, Gaëlle Lucas-Leclin, Patrick Georges, Sylvie Janicot, Laboratoire Charles Fabry / Lasers, Laboratoire Charles Fabry (LCF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS), Laboratoire de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), Institut d’Electronique et des Systèmes (IES), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Térahertz, hyperfréquence et optique (TéHO), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), and RTRA/Triangle de la Physique (2010-089T)
Subjects: Materials science, Thermal lens, Physics::Optics, 02 engineering and technology, Output coupler, VECSEL, Single-frequency, 01 natural sciences, law.invention, Semiconductor laser theory, 010309 optics, 020210 optoelectronics & photonics, Optics, law, 0103 physical sciences, Thermal, 0202 electrical engineering, electronic engineering, information engineering, Semiconductor lasers, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Plane (geometry), business.industry, Laser, Lens (optics), Semiconductor, Transmission (telecommunications), Physics::Accelerator Physics, Optoelectronics, business
Abstract: International audience; We present in this work the study of a short vertical external cavity semiconductor laser in single longitudinal operation at 852 nm without intracavity elements. Two different configurations were studied, a plane-plane configuration, stabilized by the thermal lens and a plane-concave configuration. The influence of the output coupler transmission and the thermal lens has been studied. In the plane concave configuration we have demonstrated more than 100mW in stable single frequency operation using a very compact cavity emitting around 852 nm.
Published: 2012
Full Text: View/download PDF

34. Oscillations and translation of a free cylinder in a confined flow

Author: D'Angelo, Maria Veronica, Hulin, Jean-Pierre, Auradou, Harold, Fluides, automatique, systèmes thermiques (FAST), Université Paris-Sud - Paris 11 (UP11)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Grupo de Medios Porosos [Buenos Aires] (GMP), Facultad de Ingeniería [Buenos Aires] (FIUBA), Universidad de Buenos Aires [Buenos Aires] (UBA)-Universidad de Buenos Aires [Buenos Aires] (UBA), RTRA Triangle de la Physique, and the LIA PMF-FMF (Franco-Argentinian International Associated Laboratory in the Physics and Mechanics of Fluids).
Subjects: [PHYS.PHYS.PHYS-FLU-DYN]Physics [physics]/Physics [physics]/Fluid Dynamics [physics.flu-dyn], Physics::Fluid Dynamics, Viscous Flow, Non linear dynamical systems, Laminar flows, Instabilities, Fluid Structure, Cylinder, Fluid Dynamics (physics.flu-dyn), FOS: Physical sciences, Physics - Fluid Dynamics, Confinement
Abstract: An oscillatory instability has been observed experimentally on an horizontal cylinder free to move and rotate between two parallel vertical walls of distance H; its characteristics differ both from vortex shedding driven oscillations and from those of tethered cylinders in the same geometry. The vertical motion of the cylinder, its rotation about its axis and its transverse motion across the gap have been investigated as a function of its diameter D, its density s, of the mean vertical velocity U of the fluid and of its viscosity. For a blockage ratio D/H above 0.5 and a Reynolds number Re larger then 14, oscillations of the rolling angle of the cylinder about its axis and of its transverse coordinate in the gap are observed together with periodic variations of the vertical velocity. Their frequency f is the same for the sedimentation of the cylinder in a static fluid (U = 0) and for a non-zero mean flow (U 6= 0). The Strouhal number St associated to the oscillation varies as 1/Re with : St.Re = 3 $\pm$ 0.15. The corresponding period 1/f is then independent of U and corresponds to a characteristic viscous diffusion time over a distance ~ D, implying a strong influence of the viscosity. These characteristics differ from those of vortex shedding and tethered cylinders for which St is instead roughly constant with Re and higher than here.
Published: 2012
Full Text: View/download PDF

35. Large-Area and High-Quality Epitaxial Graphene on Off-Axis SiC Wafers

Author: M. Eddrief, Rachid Belkhou, Mathieu G. Silly, Fausto Sirotti, Claire Mathieu, Abdelkarim Ouerghi, Matthieu Picher, Souliman El Moussaoui, Massimiliano Marangolo, Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), ANR, and RTRA Triangle de la Physique
Subjects: spectroscopy, Materials science, General Physics and Astronomy, Nanotechnology, 02 engineering and technology, 010402 general chemistry, 01 natural sciences, law.invention, law, General Materials Science, Wafer, Electronics, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], Graphene oxide paper, vicinal SiC, Graphene, General Engineering, low-energy electron microscopy, 021001 nanoscience & nanotechnology, epitaxial graphene, 0104 chemical sciences, Low-energy electron microscopy, electronic properties, scanning tunneling microscopy, Sublimation (phase transition), Scanning tunneling microscope, 0210 nano-technology, Graphene nanoribbons
Abstract: International audience; The growth of large and uniform graphene layers remains very challenging to this day due to the close correlation between the electronic and transport properties and the layer morphology. Here, we report the synthesis of uniform large-scale mono- and bilayers of graphene on off-axis 6H-SiC(0001) substrates. The originality of our approach consists of the fine control of the growth mode of the graphene by precise control of the Si sublimation rate. Moreover, we take advantage of the presence of nanofacets on the off-axis substrate to grow a large and uniform graphene with good long-range order. We believe that our approach represents a significant step toward the scalable synthesis of graphene films with high structural qualities and fine thickness control, in order to develop graphene-based electronic devices.
Published: 2012
Full Text: View/download PDF

36. Tunable dual-frequency laser source for coherent population trapping cesium atomic clocks

Author: Camargo, Fabiola, Georges, Patrick, Lucas-Leclin, Gaëlle, Girard, Nils, Baili, Ghaya, Morvan, Loïc, Dolfi, Daniel, Danet, Jean-Marie, Holleville, David, Guérandel, S., Sagnes, Isabelle, Laboratoire Charles Fabry / Lasers, Laboratoire Charles Fabry (LCF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS), Thales Research and Technology [Palaiseau], THALES, 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 de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), RTRA/Triangle de la Physique 2010-089T, ANR-07-BLAN-0320,2POLEVF,Two-POLarisation VECSEL for the generation of two-Frequency beams(2007), Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS), and THALES [France]
Subjects: [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics]
Abstract: conférence
Published: 2012

37. Dual frequency VECSEL at 852 nm for coherent population trapping cesium atomic clocks

Author: Camargo, Fabiola, Georges, Patrick, Lucas-Leclin, Gaëlle, Girard, Nils, Baili, Ghaya, Morvan, Loïc, Dolfi, Daniel, Danet, Jean-Marie, Holleville, David, Guerandel, S., Sagnes, Isabelle, Laboratoire Charles Fabry / Lasers, Laboratoire Charles Fabry (LCF), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)-Institut d'Optique Graduate School (IOGS), Thales Research and Technology [Palaiseau], THALES, 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 de photonique et de nanostructures (LPN), Centre National de la Recherche Scientifique (CNRS), RTRA / Triangle de la Physique (2010-089T), ANR-07-BLAN-0320,2POLEVF,Two-POLarisation VECSEL for the generation of two-Frequency beams(2007), Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-Institut d'Optique Graduate School (IOGS)-Centre National de la Recherche Scientifique (CNRS), and THALES [France]
Subjects: [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], ComputingMilieux_MISCELLANEOUS
Abstract: International audience
Published: 2012

38. Neutral Products Desorption from DNA Thin Films Induced by Low-Energy Electrons (0.5-20 eV)

Author: Omar Boulanouar, Lionel Amiaud, Michel Fromm, Cécile Sicard-Roselli, Léon Sanche, Anne Lafosse, umr 8000 ( LCP ), Université Paris-Sud - Paris 11 ( UP11 ), Institut des Sciences Moléculaires d'Orsay ( ISMO ), Université Paris-Sud - Paris 11 ( UP11 ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire Chrono-environnement ( LCE ), Université Bourgogne Franche-Comté ( UBFC ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Franche-Comté ( UFC ), Centre for Research in Radiooncology, University de Sherbrooke (Canada), RTRA Triangle de la Physique ECCL Cost action CM0601 ('Electron and Positron Induced Chemistry', Framework V), Laboratoire de Chimie Physique D'Orsay (LCPO), Université Paris-Sud - Paris 11 (UP11)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences Moléculaires d'Orsay (ISMO), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Chrono-environnement - CNRS - UBFC (UMR 6249) (LCE), Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS), and Université de Sherbrooke (UdeS)
Subjects: [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry, [ CHIM.THEO ] Chemical Sciences/Theoretical and/or physical chemistry
Abstract: International audience; Low-energy electrons (LEEs) are produced in great amount in the biological medium, when submitted to high-energy radiations. They have the ability to induce strand breaks in the DNA duplex, as proven by electrophoresis analysis of irradiated dry deposits. LEE interactions with target molecules induce the formation of different species such as anions, cations, radicals and neutrals. The desorption of anionic species from oligonucleotides and DNA under LEEs irradiation has been intensively explored. The involved mechanisms and sites were successfully identified, including the resonant formation of transient negative ions (TNI) below 15 eV. However, the desorption of neutral products was less explored [4], due to their difficult detection. Exploring this aspect will provide additional information and complete the picture of the dissociating pathways followed by TNIs.
Published: 2011

39. Experimental Evidence of Fluctuation-Dissipation Theorem Violation in a Superspin Glass

Author: Komatsu, Katsuyoshi, L'Hote, D., Nakamae, Sawako, Mosser, Vincent, Konczykowski, Marcin, Dubois, Emmanuelle, Dupuis, V., Perzynski, Régine, Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), itron (ITRON), ITRON, Laboratoire des Solides Irradiés (LSI), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X), Physicochimie des Electrolytes, Colloïdes et Sciences Analytiques (PECSA), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC), RTRA-Triangle de la Physique under the contracts, Micro-Hall and DynMag., Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Ecole Superieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Condensed Matter::Soft Condensed Matter, Fluctuation Disspipation Theorem Violation Superspin Glass, FOS: Physical sciences, Disordered Systems and Neural Networks (cond-mat.dis-nn), [PHYS.COND.CM-DS-NN]Physics [physics]/Condensed Matter [cond-mat]/Disordered Systems and Neural Networks [cond-mat.dis-nn], Condensed Matter - Disordered Systems and Neural Networks, Condensed Matter::Disordered Systems and Neural Networks
Abstract: We present the experimental observation of the fluctuation-dissipation theorem (FDT) violation in an assembly of interacting magnetic nanoparticles in the low temperature superspin glass phase. The magnetic noise is measured with a two-dimension electron gas Hall probe and compared to the out of phase ac susceptibility of the same ferrofluid. For "intermediate" aging times of the order of 1 h, the ratio of the effective temperature $T_{\rm eff}$ to the bath temperature T grows from 1 to 6.5 when T is lowered from $T_g$ to 0.3 $T_g$, regardless of the noise frequency. These values are comparable to those measured in an atomic spin glass as well as those calculated for a Heisenberg spin glass.
Published: 2011
Full Text: View/download PDF

40. Epitaxial growth and ferrimagnetic behavior of MnFe2O4(111) ultrathin layers for room-temperature spin filtering

Author: Matzen, S., Moussy, J. -B., Mattana, R., Bouzehouane, K., Deranlot, C., Petroff, F., Cezar, J. C., Arrio, M. -A., Sainctavit, Ph., Gatel, Christophe, Warot-Fonrose, Bénédicte, Zheng, Y., Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Unité mixte de physique CNRS/Thales (UMPhy CNRS/THALES), THALES-Centre National de la Recherche Scientifique (CNRS), Institut de minéralogie et de physique des milieux condensés (IMPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Centre d'élaboration de matériaux et d'études structurales (CEMES), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), C'nano IdF [FILASPIN], RTRA-Triangle de la Physique [MicMMaC], THALES [France]-Centre National de la Recherche Scientifique (CNRS), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), and Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)
Subjects: 7547Lx, number(s): 7570−i, 8575−d, 7525−j, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat]
Abstract: International audience; We report on the epitaxial growth and physical properties of spinel MnFe2O4(111) thin films with thicknesses down to 2 nm. The thin films, grown on alpha-Al2O3(0001) single crystals or Pt(111) buffer layers by oxygen-assisted molecular beam epitaxy, exhibit high structural order with sharp interfaces and low roughness. The electrical and magnetic properties are carefully investigated and it is shown that MnFe2O4(111) ultrathin films keep an insulating and ferrimagnetic behavior at room temperature. Special attention is given to the iron/manganese valence state and the cationic ordering. X-ray absorption spectroscopy and magnetic circular dichroism measurements reveal that thin films contain mainly Fe3+ and Mn2+ cations, distributed predominantly in a normal spinel structure. This study proves the high potential of MnFe2O4 to be used as a magnetic tunnel barrier for spin filtering applications at room temperature.
Published: 2011
Full Text: View/download PDF

41. Characterization of fracture void space heterogeneity by electrical impedance measurement

Author: Boschan, Alejandro, Ippolito, Irene, Chertcoff, Ricardo, Hulin, Jean-Pierre, Auradou, Harold, Fluides, automatique, systèmes thermiques (FAST), Université Paris-Sud - Paris 11 (UP11)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Grupo de Medios Porosos [Buenos Aires] (GMP), Facultad de Ingeniería [Buenos Aires] (FIUBA), Universidad de Buenos Aires [Buenos Aires] (UBA)-Universidad de Buenos Aires [Buenos Aires] (UBA), European Hot Dry Rock Association, Laboratoire International Associé Physique et Mécanique des Fluides, RTRA 'Triangle de la Physique', LIA PMF-FMF, and European Project
Subjects: [PHYS.PHYS.PHYS-FLU-DYN]Physics [physics]/Physics [physics]/Fluid Dynamics [physics.flu-dyn], [SDE.MCG]Environmental Sciences/Global Changes, Solute, Heterogeneity, [SDU.STU.HY]Sciences of the Universe [physics]/Earth Sciences/Hydrology, Fractures, Roughness, Electrical, Channeling
Abstract: International audience; The possible characterization of the heterogeneity of the aperture field in rough fractures by electrical impedance measurement is demonstrated through displacement experiments using two miscible fluids of different electrical resistivity. Two model fractures have been used: their complementary rough walls are identical but have different relative shear displacements creating ``channel'' or `barrier'' structures in the void space, respectively parallel or perpendicular to the mean flow velocity $\vec{U}$. In the (``channel'') geometry, the global electrical resistance displays an initial linear variation followed by a ``tail'' part reflecting the contrast between slow and fast flow channels. In the (``barrier'') geometry, the existence of a change in the slope between two linear zones suggests the appearance of domains of different permeabilities along the fracture. These variations are well reproduced theoretically and numerically either by assuming independent flow channels parallel to $\vec{U}$ (channel case) or an aperture that varies only along the flow (barrier case). For each configuration, we present a specific inversion procedure that allows one to extract the key features of the heterogeneity from the resistance variation.
Published: 2010
Full Text: View/download PDF

42. Permeability Estimates of Self-Affine Fracture Faults Based on Generalization of the Bottle Neck Concept

Author: Talon, Laurent, Auradou, Harold, Hansen, Alex, Fluides, automatique, systèmes thermiques (FAST), Université Paris-Sud - Paris 11 (UP11)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Department of Physics [Trondheim] (Physics NTNU), Norwegian University of Science and Technology [Trondheim] (NTNU), Norwegian University of Science and Technology (NTNU)-Norwegian University of Science and Technology (NTNU), RTRA Triangle de la Physique, and PICS research project: 'The Physics of Geological Complex Systems'
Subjects: [PHYS.PHYS.PHYS-FLU-DYN]Physics [physics]/Physics [physics]/Fluid Dynamics [physics.flu-dyn], Fracture, Rough Fractures, Fluid Dynamics (physics.flu-dyn), FOS: Physical sciences, Worst Path, Physics - Fluid Dynamics, Hydraulic Barrier, Fractal, Permeability, Physics::Geophysics
Abstract: International audience; We propose a method for calculating the effective permeability of two-dimensional self-affine permeability fields based on generalizing the one-dimensional concept of a bottleneck. We test the method on fracture faults where the local permeability field is given by the cube of the aperture field. The method remains accurate even when there is substantial mechanical overlap between the two fracture surfaces. The computational efficiency of the method is comparable to calculating a simple average and is more than two orders of magnitude faster than solving the Reynolds equations using a finite-difference scheme.
Published: 2010
Full Text: View/download PDF

43. Photoassociation of a cold atom-molecule pair: long-range quadrupole-quadrupole interactions

Author: Maxence Lepers, Olivier Dulieu, Viatcheslav Kokoouline, Laboratoire Aimé Cotton (LAC), École normale supérieure - Cachan (ENS Cachan)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), and RTRA Triangle de la Physique projet QCCM
Subjects: Atomic Physics (physics.atom-ph), FOS: Physical sciences, 02 engineering and technology, 01 natural sciences, Molecular physics, Physics - Atomic Physics, [PHYS.QPHY]Physics [physics]/Quantum Physics [quant-ph], Ultracold atom, Physics - Chemical Physics, 0103 physical sciences, Atom, Physics::Atomic and Molecular Clusters, Molecule, Physics::Atomic Physics, 010306 general physics, multipolar expansion, Chemical Physics (physics.chem-ph), Physics, Condensed Matter::Quantum Gases, Quantum Physics, [PHYS.PHYS.PHYS-ATOM-PH]Physics [physics]/Physics [physics]/Atomic Physics [physics.atom-ph], long-range interaction, 021001 nanoscience & nanotechnology, Electrostatics, Potential energy, Diatomic molecule, Atomic and Molecular Physics, and Optics, Excited state, Quadrupole, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Atomic physics, photoassociation, Quantum Physics (quant-ph), 0210 nano-technology, cold molecules
Abstract: The general formalism of the multipolar expansion of electrostatic interactions is applied to the calculation the potential energy between an excited atom (without fine structure) and a ground state diatomic molecule at large separations. Both partners exhibit a permanent quadrupole moment, so that their mutual quadrupole-quadrupole long-range interaction is attractive enough to bind trimers. Numerical results are given for an excited Cs(6P) atom and a ground state Cs2 molecule. The prospects for achieving photoassociation of a cold atom/dimer pair is thus discussed and found promising. The formalism can be easily generalized to the long-range interaction between molecules to investigate the formation of cold tetramers., Comment: 5 figures
Published: 2010

44. Universal Scaling of the Quantum Conductance of an Inversion-Symmetric Interacting Model

Author: Jean-Louis Pichard, Axel Freyn, Théorie Quantique des Circuits (ThQC), Institut Néel (NEEL), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF), Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), RTRA 'Triangle de la Physique' of Palaiseau-Orsay-Saclay, Théorie Quantique des Circuits (NEEL - ThQC), and Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)
Subjects: Point reflection, Quantum point contact, FOS: Physical sciences, 01 natural sciences, 010305 fluids & plasmas, Lattice (order), Quantum mechanics, 0103 physical sciences, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), 010306 general physics, Anderson impurity model, [PHYS.COND.CM-MSQHE]Physics [physics]/Condensed Matter [cond-mat]/Mesoscopic Systems and Quantum Hall Effect [cond-mat.mes-hall], systèmes mésoscopiques, Physics, Spins, Condensed Matter - Mesoscale and Nanoscale Physics, Hartree-Fock, Fermion, Condensed Matter Physics, effet Kondo orbital, Electronic, Optical and Magnetic Materials, interaction electron-electron, algorithme NRG, Condensed Matter::Strongly Correlated Electrons, Kondo effect, Conductance quantique, Dimensionless quantity
Abstract: We consider quantum transport of spinless fermions in a 1D lattice embedding an interacting region (two sites with inter-site repulsion U and inter-site hopping td, coupled to leads by hopping terms tc). Using the numerical renormalization group for the particle-hole symmetric case, we study the quantum conductance g as a function of the inter-site hopping td. The interacting region, which is perfectly reflecting when td -> 0 or td -> infinity, becomes perfectly transmitting if td takes an intermediate value ��(U,tc) which defines the characteristic energy of this interacting model. When td < tc sqrt(U), g is given by a universal function of the dimensionless ratio X=td/��. This universality characterizes the non-interacting regime where ��=tc^2, the perturbative regime (U < tc^2) where ��can be obtained using Hartree-Fock theory, and the non-perturbative regime (U > tc^2) where ��is twice the characteristic temperature TK of an orbital Kondo effect induced by the inversion symmetry. When td < ��, the expression g(X)=4/(X+1/X)^2 valid without interaction describes also the conductance in the presence of the interaction. To obtain those results, we map this spinless model onto an Anderson model with spins, where the quantum impurity is at the end point of a semi-infinite 1D lead and where td plays the role of a magnetic field h. This allows us to describe g(td) using exact results obtained for the magnetization m(h) of the Anderson model at zero temperature. We expect this universal scaling to be valid also in models with 2D leads, and observable using 2D semi-conductor heterostructures and an interacting region made of two identical quantum dots with strong capacitive inter-dot coupling and connected via a tunable quantum point contact., 14 pages, 18 figures
Published: 2010
Full Text: View/download PDF

45. Influence of a static magnetic field on the photoluminescence of an ensemble of Nitrogen-Vacancy color centers in a diamond single-crystal

Author: Fedor Jelezko, Ngoc Diep Lai, François Treussart, Dingwei Zheng, Jean-François Roch, Lai, Ngoc Diep, Laboratoire de Photonique Quantique et Moléculaire (LPQM), École normale supérieure - Cachan (ENS Cachan)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Stuttgart University, EQUIND (FP6 project number IST-034368), NEDQIT (ERANET Nano-Sci), B-DIAMANT (RTRA 'Triangle de la Physique'), and Centre National de la Recherche Scientifique (CNRS)-CentraleSupélec-École normale supérieure - Cachan (ENS Cachan)
Subjects: [PHYS.PHYS.PHYS-OPTICS] Physics [physics]/Physics [physics]/Optics [physics.optics], Physics and Astronomy (miscellaneous), Spin states, Magnetometer, FOS: Physical sciences, 02 engineering and technology, engineering.material, 01 natural sciences, law.invention, magnetometry, [PHYS.QPHY]Physics [physics]/Quantum Physics [quant-ph], law, Electron spin resonance, 0103 physical sciences, Radiative transfer, 010306 general physics, optical dipoles, ComputingMilieux_MISCELLANEOUS, [PHYS.QPHY] Physics [physics]/Quantum Physics [quant-ph], [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Condensed Matter - Materials Science, Quantum Physics, Chemistry, Materials Science (cond-mat.mtrl-sci), Diamond, PACS: 72.25.Fe, 78.70.Gq, 42.50.Tx, 42.50.Dv, 03.67.-a, 021001 nanoscience & nanotechnology, Magnetostatics, Magnetic field, diamond nanocrystal, engineering, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Atomic physics, Quantum Physics (quant-ph), 0210 nano-technology, Single crystal, Excitation
Abstract: We investigate the electron spin resonance of an ensemble of Nitrogen-Vacancy (NV) color centers in a bulk diamond crystal. The four possible orientations of the NV-center in the lattice lead to different dependences on the magnitude and the orientation of an external static magnetic field. Experimental results obtained with a continuous microwave excitation are in good agreement with simulations. In addition, we observe that the average radiative lifetime of the NV color center is also modified when the external magnetic field is applied. This variation is explained by the mixing between mS = 0 and mS = $\pm$1 spin states of the NV-center with different radiative lifetimes, due to magnetic coupling. These results are of interest for a broad range of applications, such as spin-resonance-based magnetometry with a high-density ensemble of NV-centers, 14 pages, published on Applied Physics Letters journal
Published: 2009

46. Atomic oxidation of large area epitaxial graphene on 4H-SiC(0001)

Author: F. Sirtti, E. Velez-Fort, Massimiliano Marangolo, Mathieu G. Silly, Abdelkarim Ouerghi, Abhay Shukla, M. Eddrief, Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), ANR, and RTRA Triangle de la Physique
Subjects: Materials science, Physics and Astronomy (miscellaneous), Absorption spectroscopy, Extended X-ray absorption fine structure, Photoemission spectroscopy, Graphene, Analytical chemistry, Substrate (electronics), Epitaxy, XANES, law.invention, symbols.namesake, law, Chemical physics, symbols, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], Raman spectroscopy
Abstract: International audience; Structural and electronic properties of epitaxial graphene on 4H-SiC were studied before and after an atomic oxidation process. X-ray photoemission spectroscopy indicates that oxygen penetrates into the substrate and decouples a part of the interface layer. Raman spectroscopy demonstrates the increase of defects due to the presence of oxygen. Interestingly, we observed on the near edge x-ray absorption fine structure spectra a splitting of the pi* peak into two distinct resonances centered at 284.7 and 285.2 eV. This double structure smears out after the oxidation process and permits to probe the interface architecture between graphene and the substrate. (C) 2014 AIP Publishing LLC.
Published: 2014
Full Text: View/download PDF

47. Potential energy and dipole moment surfaces of H3− molecule

Author: Olivier Dulieu, Viatcheslav Kokoouline, R. Guerout, M. Ayouz, J. Robert, Laboratoire Aimé Cotton (LAC), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11)-École normale supérieure - Cachan (ENS Cachan), Laboratoire Kastler Brossel (LKB (Jussieu)), Université Pierre et Marie Curie - Paris 6 (UPMC)-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)-Centre National de la Recherche Scientifique (CNRS), RTRA Triangle de la Physique projet QCCM, École normale supérieure - Cachan (ENS Cachan)-Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), 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)-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), and Dulieu, Olivier
Subjects: Atomic Physics (physics.atom-ph), FOS: Physical sciences, General Physics and Astronomy, 7. Clean energy, 01 natural sciences, [PHYS.PHYS.PHYS-CHEM-PH] Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Physics - Atomic Physics, Ion, Physics - Chemical Physics, 0103 physical sciences, Molecule, [PHYS.PHYS.PHYS-ATOM-PH] Physics [physics]/Physics [physics]/Atomic Physics [physics.atom-ph], Physical and Theoretical Chemistry, permanent dipole moment, 010306 general physics, H3, radiative association, Chemical Physics (physics.chem-ph), Physics, [PHYS.PHYS.PHYS-ATOM-PH]Physics [physics]/Physics [physics]/Atomic Physics [physics.atom-ph], 010304 chemical physics, Triatomic molecule, CEPA, Potential energy, Dipole, Moment (physics), Potential energy surface, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Atomic physics, Ground state, potential energy surface
Abstract: A new potential energy surface for the electronic ground state of the simplest triatomic anion H(3) (-) is determined for a large number of geometries. Its accuracy is improved at short and large distances compared to previous studies. The permanent dipole moment surface of the state is also computed for the first time. Nine vibrational levels of H(3) (-) and 14 levels of D(3) (-) are obtained, bound by at most approximately 70 and approximately 126 cm(-1), respectively. These results should guide the spectroscopic search of the H(3) (-) ion in cold gases (below 100K) of molecular hydrogen in the presence of H(-) ions.
Published: 2010
Full Text: View/download PDF

Catalog

Books, media, physical & digital resources

See catalog results

Searchworks

Select search scope, currently: Articles Catalog books, media & more in Jio Institute collections Articles journal articles & other e-resources

Search

Search Constraints

Refine your results

Search Limiters

Topic

Publication Year Range

Language

Journal

Database

Publisher

47 results on '"RTRA Triangle de la Physique"'

Search Results

Catalog

Select search scope, currently: Articles

Catalog

books, media & more in Jio Institute collections

Articles

journal articles & other e-resources