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187 results on '"Automatisation '

1. Les bulles de filtres sur les médias socionumériques et formation de l'opinion

Author: Dufrasne, Marie, Philippette, Thibault, Kick-off Anticipate 2018 Axe \\'Intelligence Artificielle, digitalisation et automatisation\\', USL-B - Pôle de Recherches sur la Communication et les Médias (PReCoM), and UCL - SSH/ILC/PCOM - Pôle de recherche en communication
Subjects: bulles de filtres, intelligence artificielle, opinion, Algorithme
Abstract: La recherche Alg-opinion s’intéresse aux effets des « bulles de filtres » ou « bulles informationnelles » sur la formation des opinions. Cette notion désigne d’un point de vue technique, l’espace informationnel rendu immédiatement accessible à un·e internaute par une plateforme numérique, résultant de nombreux processus algorithmiques de filtrage et de profilage et, d’un point de vue social, l’isolement intellectuel et culturel éprouvé par les internautes, lorsque les informations auxquelles ils et elles accèdent en ligne sont le résultat de processus algorithmiques difficilement intelligibles. Les bulles informationnelles soulèvent une série d’interrogations quant à la vulnérabilité de certains publics (les adolescent·e·s, les jeunes ou les peu instruit·e·s notamment), à leur impact sur la formation des opinions et au peu d’intelligibilité des algorithmes utilisés dans le cadre de la recherche informationnelles (l’actualité notamment).
Published: 2018

2. Les bulles de filtres sur les médias socionumériques et formation de l'opinion

Author: USL-B - Pôle de Recherches sur la Communication et les Médias (PReCoM), UCL - SSH/ILC/PCOM - Pôle de recherche en communication, Dufrasne, Marie, Philippette, Thibault, Kick-off Anticipate 2018 Axe "Intelligence Artificielle, digitalisation et automatisation", USL-B - Pôle de Recherches sur la Communication et les Médias (PReCoM), UCL - SSH/ILC/PCOM - Pôle de recherche en communication, Dufrasne, Marie, Philippette, Thibault, and Kick-off Anticipate 2018 Axe "Intelligence Artificielle, digitalisation et automatisation"
Abstract: La recherche Alg-opinion s’intéresse aux effets des « bulles de filtres » ou « bulles informationnelles » sur la formation des opinions. Cette notion désigne d’un point de vue technique, l’espace informationnel rendu immédiatement accessible à un·e internaute par une plateforme numérique, résultant de nombreux processus algorithmiques de filtrage et de profilage et, d’un point de vue social, l’isolement intellectuel et culturel éprouvé par les internautes, lorsque les informations auxquelles ils et elles accèdent en ligne sont le résultat de processus algorithmiques difficilement intelligibles. Les bulles informationnelles soulèvent une série d’interrogations quant à la vulnérabilité de certains publics (les adolescent·e·s, les jeunes ou les peu instruit·e·s notamment), à leur impact sur la formation des opinions et au peu d’intelligibilité des algorithmes utilisés dans le cadre de la recherche informationnelles (l’actualité notamment).
Published: 2018

3. Methodology to design computer integrated manufacturing and control of manufacturing unit

Author: Association pour le DEveloppement des Techniques d'Automatisation en Aquitaine, Doumeingts, Guy, Goos, G., editor, Hartmanis, J., editor, Barstow, D., editor, Brauer, W., editor, Brinch Hansen, P., editor, Gries, D., editor, Luckham, D., editor, Moler, C., editor, Pnueli, A., editor, Seegmüller, G., editor, Stoer, J., editor, Wirth, N., editor, Rembold, U., editor, and Dillmann, R., editor
Published: 1984
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4. Les objets nomades et la Bibliothèque

Author: 1ère conférence européenne Automatisation et les Réseaux de Bibliothèques (9-11/05/1990: Palais des Congrès, Bruxelles), Prigogine, Ilya, 1ère conférence européenne Automatisation et les Réseaux de Bibliothèques (9-11/05/1990: Palais des Congrès, Bruxelles), and Prigogine, Ilya
Abstract: NOTXT, info:eu-repo/semantics/nonPublished
Published: 1990

5. An Interactive micromanipulation station combined to a confocal XRF instrument: proof of concept

Author: Sabine Douillet, D. Tonneau, Florence Marchi, Hichem Maradj, David Renahy, Sebastien Lavandier, Carole Fauquet, Clément Girod, Nano-Optique et Forces (NOF), Institut Néel (NEEL), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Aix Marseille Université (AMU), Centre Interdisciplinaire de Nanoscience de Marseille (CINaM), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Automatisation et Caractérisation (AUTOCARAC), Nano-Optique et Forces (NEEL - NOF), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), and Automatisation & caractérisation (NEEL - AUTOCARAC)
Subjects: Grippers, Computer science, Proof of concept, business.industry, Confocal, Computer graphics (images), ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION, business, Force sensor, ComputingMilieux_MISCELLANEOUS, Haptic technology, Graphical user interface, [SPI.AUTO]Engineering Sciences [physics]/Automatic
Abstract: We designed and developed an interactive micromanipulation station based on a commercial microgripper equipped with a force sensor. Through a haptic device and a custom-developed Graphical User Interface (GUI), the user can pilot the different parts of the station. This interactive station has been combined to a confocal X-ray Fluorescence (XRF) instrument. A tip-shaped W microwire has been remotely manipulated and placed within the tightly focused X-ray spot of the equipment. Several XRF spectra have been recorded along the tip extremity. This led to the determination of the ultimate volume resolution that can be achieved with this laboratory confocal XRF instrument.
Published: 2020
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6. Field-induced double spin spiral in a frustrated chiral magnet

Author: Mahesh Ramakrishnan, Evan Constable, Andres Cano, Maxim Mostovoy, Jonathan S. White, Namrata Gurung, Enrico Schierle, Sophie de Brion, Claire V. Colin, Frederic Gay, Pascal Lejay, Eric Ressouche, Eugen Weschke, Valerio Scagnoli, Rafik Ballou, Virginie Simonet, Urs Staub, Theory of Condensed Matter, Solid State Materials for Electronics, The Swiss Light Source (SLS) (SLS-PSI), Paul Scherrer Institute (PSI), Magnétisme et Supraconductivité (NEEL - MagSup), Institut Néel (NEEL), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Vienna University of Technology (TU Wien), Théorie de la Matière Condensée (NEEL - TMC), Zernike Institute of Advanced Materials, University of Groningen [Groningen], Department of Materials [ETH Zürich] (D-MATL), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Helmoltz-Zentrum Berlin für Materialien und Energie (GmbH), Matériaux, Rayonnements, Structure (NEEL - MRS), Automatisation & caractérisation (NEEL - AUTOCARAC), Croissance Cristalline et MicroAnalyse (NEEL - C2MA), Magnétisme et Diffusion Neutronique (MDN), Modélisation et Exploration des Matériaux (MEM), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Magnétisme et Supraconductivité (MagSup ), Théorie de la Matière Condensée (TMC ), Matériaux, Rayonnements, Structure (MRS), Automatisation et Caractérisation (AUTOCARAC ), Cristaux Massifs (CrisMass), Institut de Recherche Interdisciplinaire de Grenoble (IRIG), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])
Subjects: Condensed Matter - Strongly Correlated Electrons, Strongly Correlated Electrons (cond-mat.str-el), MIXED-STATE, lcsh:TA401-492, FOS: Physical sciences, lcsh:Materials of engineering and construction. Mechanics of materials, PHASE-TRANSITIONS, [PHYS.COND.CM-SCE]Physics [physics]/Condensed Matter [cond-mat]/Strongly Correlated Electrons [cond-mat.str-el], lcsh:Atomic physics. Constitution and properties of matter, ComputingMilieux_MISCELLANEOUS, lcsh:QC170-197
Abstract: Magnetic ground states with peculiar spin textures, such as magnetic skyrmions and multifunctional domains are of enormous interest for the fundamental physics governing their origin as well as potential applications in emerging technologies. Of particular interest are multiferroics, where sophisticated interactions between electric and magnetic phenomena can be used to tailor several functionalities. We report the direct observation of a magnetic field induced long-wavelength spin spiral modulation in the chiral compound Ba3TaFe3Si2O14, which emerges out of a helical ground state, and is hallmarked by the onset of a unique chirality-dependent contribution to the bulk electric polarization. The periodicity of the field-induced modulation, several hundreds of nm depending on the field value, is comparable to the length scales of mesoscopic topological defects such as skyrmions, merons, and solitons. The phase transition and observed threshold behavior are consistent with a phenomenology based on the allowed Lifshitz invariants for the chiral symmetry of langasite, which intriguingly contain all the essential ingredients for the realization of topologically stable antiferromagnetic skyrmions. Our findings open up new directions to explore topological correlations of antiferromagnetic spintronic systems based on non-collinear magnetic systems with additional ferroic functionalities., npj Quantum Materials, 4 (1), ISSN:2397-4648
Published: 2019
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7. Long flexible melt-spun Ni–Co–Mn–In ribbons with shape memory effect and caloric perfomances above 300 K

Author: S. Miraglia, Marc Verdier, H. Dufour, M. Silveira Reis Perticarrari, Daniel Bourgault, Sébastien Pairis, F. Porcher, Richard Haettel, P. Plaindoux, J. Jarreau, Laureline Porcar, Thermodynamique et biophysique des petits systèmes (NEEL - TPS), Institut Néel (NEEL), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Matériaux, Rayonnements, Structure (NEEL - MRS), Laboratoire Léon Brillouin (LLB - UMR 12), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Ingénierie Expérimentale (NEEL - ExpE), Automatisation & caractérisation (NEEL - AUTOCARAC), Croissance Cristalline et MicroAnalyse (NEEL - C2MA), Science et Ingénierie des Matériaux et Procédés (SIMaP ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Thermodynamique et biophysique des petits systèmes (TPS), Matériaux, Rayonnements, Structure (MRS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Université Paris-Saclay, Thermique Elaboration Matériaux Applications (ThEMA), Automatisation et Caractérisation (AUTOCARAC ), Optique et microscopies (POM), Ingénierie Expérimentale (ExpE), Consortium de Recherches pour l'Emergence des Technologies Avancées (CRETA), and Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])
Subjects: 010302 applied physics, Materials science, Refrigeration, [CHIM.MATE]Chemical Sciences/Material chemistry, 02 engineering and technology, Shape-memory alloy, 021001 nanoscience & nanotechnology, 7. Clean energy, 01 natural sciences, Brittleness, Magnetic shape-memory alloy, 0103 physical sciences, Ribbon, Magnetic refrigeration, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], General Materials Science, Composite material, 0210 nano-technology, Actuator, Energy harvesting, ComputingMilieux_MISCELLANEOUS
Abstract: Magnetic shape memory alloys (MSMAs) and in particular Ni–Mn based Heusler materials are a new class of functional materials capable of magnetic-field-induced actuation, mechanical sensing, magnetocaloric and elastocaloric refrigeration as well as energy harvesting. However innovative ideas are needed to overcome many obstacles such as mechanical brittleness and materials shaping while having interesting functional properties. In the present work, flexible Ni45Co5Mn50-xInx ribbons with different x compositions have been developed by melt-spinning process. Good magnetic properties and bending strain up to 1% are very interesting for the use of these ribbons as actuators, sensors or in the field of magnetocaloric cooling. Entropy variations of about 15 J/kg K under 5 T and a cooling recovery RCeff of 144 J/kg can be obtained at around 300 K. Long ribbon lengths close to 20 cm with a two-way shape memory effect have been processed. We present a complete set of properties (magnetic, crystallographic, mechanical, actuating) for the optimal composition x = 12.5.
Published: 2019
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8. Differences and Similarities between Lanthanum and Rare-Earth Iodate Anhydrous Polymorphs: Structures, Thermal Behaviors, and Luminescent Properties

Author: Yan Suffren, Olivier Leynaud, Isabelle Gautier-Luneau, Alain Brenier, Philippe Plaindoux, Optique et Matériaux (NEEL - OPTIMA), Institut Néel (NEEL), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), 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), X'Press : diffraction et hautes pressions (NEEL - X'Press), Automatisation & caractérisation (NEEL - AUTOCARAC), Institut Lumière Matière [Villeurbanne] (ILM), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Optique et Matériaux (OPTIMA ), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-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)-Ecole Nationale Supérieure de Chimie de Rennes (ENSCR)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), X'Press (X'Press), Automatisation et Caractérisation (AUTOCARAC ), 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), and Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)
Subjects: Lanthanide, metal iodates, infrared nonlinear optics, Inorganic chemistry, chemistry.chemical_element, 02 engineering and technology, Crystal structure, 010402 general chemistry, 01 natural sciences, Inorganic Chemistry, chemistry.chemical_compound, Differential scanning calorimetry, matrices, Lanthanum, [CHIM]Chemical Sciences, polar, Physical and Theoretical Chemistry, Isostructural, Iodate, transparency, crystal-structure, 021001 nanoscience & nanotechnology, laser, 0104 chemical sciences, 2nd-harmonic generation, Crystallography, chemistry, Acentric factor, sphere, nd, 0210 nano-technology, Solid solution
Abstract: International audience; The Ln(IO)(HIO) (y = 1 or 1.33) compounds are isostructural with the La(IO)(HIO) phases, but thermal studies reveal different behaviors. On the one hand, the partial thermal decompositions of these lanthanide compounds lead to the Ln(IO) formulation, with a room temperature structure different from the β-La(IO) obtained from La(IO)(HIO). On the other hand, the partial thermal decompositions of the LaLn(IO)(HIO) compounds prepared with lanthanides ions (Ce, Pr, Nd, Sm, Eu, Gd, and Yb) lead to acentric β-LaLn(IO). As for β-La(IO), reversible structural transitions from β-LaLn(IO) to centrosymmetric γ-LaLn(IO) are observed. Differential scanning calorimetry analyses of LaLn(IO) solid solutions show that the transition temperatures vary with the lanthanide concentration in the solid solution. A transition is observed only up to a certain fraction of lanthanide-ion substitution; this substitution limit decreases with the cationic radius of the lanthanide ion. Finally, the β-LaNd(IO) and β-LaYb(IO) phases are investigated by luminescence spectroscopy.
Published: 2016
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9. Temperature Variation of Magnetic Anisotropy in Pt / Co / AlO x Trilayers

Author: Garad, H., Fettar, F., Gay, F., Joly, Y., Auffret, S., Rodmacq, B., Dieny, B., Ortega, L., Surfaces, Interfaces et Nanostructures (SIN ), Institut Néel (NEEL), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Automatisation et Caractérisation (AUTOCARAC ), SPINtronique et TEchnologie des Composants (SPINTEC), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Laboratoire de Physique des Solides (LPS), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), European Project: 669204,H2020,ERC-2014-ADG,MAGICAL(2015), Surfaces, Interfaces et Nanostructures (NEEL - SIN), Automatisation & caractérisation (NEEL - AUTOCARAC), and Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Condensed Matter::Materials Science, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]
Abstract: International audience; Hysteresis-loop measurements using an extraordinary Hall effect are carried out at different temperatures (4.2–300 K) in Pt=Co=AlO x trilayers. The AlO x layer is prepared by plasma oxidation of the Al capping layer during various oxidation times. The samples are subsequently annealed at different temperatures ð300 °C–450 °CÞ. Most of the samples exhibit perpendicular anisotropy of increasingly high amplitude as the measurement temperature decreases. In addition, some samples exhibit unusual phenomena such as a temperature-induced reorientation of anisotropy from in plane to out of plane or a large increase of anisotropy at low temperature associated with the onset of exchange bias. The perpendicular magnetic anisotropy, coercivity, thermally induced anisotropy reorientation, and exchange-bias effects are explained by the influence of different chemical bonds, namely, Co─Al, Co─O, and Co─Pt, which appear and/or evolve as a function of oxidation time and annealing temperature. They are linked to the formation of new phases such as CoO or CoPt alloy and to the evolution of the Co=AlO x , Co=Pt, and Co=CoO interfaces modified by the oxidation time and the interdiffusion between species taking place during the anneals.
Published: 2017
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10. Puzzling evidence for surface superconductivity in the layered dichalcogenide Cu10%TiSe2

Author: Levy-Bertrand, F., Michon, B., Marcus, J., Marcenat, C., Kačmarčík, J., Klein, T., Cercellier, H., MagSup - Magnétisme et Supraconductivité, Institut Néel (NEEL), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF), Cultures et Sociétés en Europe (CSE), Université Marc Bloch - Strasbourg II-Centre National de la Recherche Scientifique (CNRS), AUTOCARAC - Automatisation et Caractérisation, Laboratoire de Transport Electronique Quantique et Supraconductivité (LaTEQS), PHotonique, ELectronique et Ingénierie QuantiqueS (PHELIQS), Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Centre of Low Temperature Physics IEP SAS (CLTP), Slovak Academy of Science [Bratislava] (SAS), Magnétisme et Supraconductivité (MagSup ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Automatisation et Caractérisation (AUTOCARAC ), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Magnétisme et Supraconductivité (NEEL - MagSup), and Automatisation & caractérisation (NEEL - AUTOCARAC)
Subjects: [PHYS.COND.CM-S]Physics [physics]/Condensed Matter [cond-mat]/Superconductivity [cond-mat.supr-con], PACS: 47.25.F-, 74.25.Bt, 74.25.Op, 74.75.+c, Condensed Matter::Superconductivity, transport, surface superconductivity, dichalcogenide, specific heat
Abstract: International audience; We report on specific heat and magnetotransport measurements performed on superconducting Cu 10% TiSe 2 single crystals. We show that superconductivity persists in transport measurements up to magnetic fields H R well above the upper critical field H c2 deduced from the calorimetric measurements. Surprisingly this " surface " superconductivity is present for all magnetic field orientations, either parallel or perpendicular to the layers. For Hab, the temperature dependence of the H R /H c2 ratio can be well reproduced by solving the Ginzburg-Landau equations in presence of a surface layer with reduced superconducting properties. Unexpectedly this temperature dependence does not depend on the field orientation.
Published: 2016
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11. Multi types and reasonable space

Author: Beniamino Accattoli, Ugo Dal Lago, Gabriele Vanoni, Accattoli, B, Dal Lago, U, Vanoni, G, Automatisation et ReprésenTation: fOndation du calcUl et de la déducTion (PARTOUT), Laboratoire d'informatique de l'École polytechnique [Palaiseau] (LIX), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Foundations of Component-based Ubiquitous Systems (FOCUS), Inria Sophia Antipolis - Méditerranée (CRISAM), Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Dipartimento di Informatica - Scienza e Ingegneria [Bologna] (DISI), Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO)-Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), and University of Bologna/Università di Bologna
Subjects: lambda calculu, intersection type, intersection types, abstract machines, [INFO.INFO-LO]Computer Science [cs]/Logic in Computer Science [cs.LO], cost model, lambda calculus, cost models, Safety, Risk, Reliability and Quality, space complexity, Software, abstract machine
Abstract: International audience; Accattoli, Dal Lago, and Vanoni have recently proved that the space used by the Space KAM, a variant of the Krivine abstract machine, is a reasonable space cost model for the λ-calculus accounting for logarithmic space, solving a longstanding open problem. In this paper, we provide a new system of multi types (a variant of intersection types) and extract from multi type derivations the space used by the Space KAM, capturing into a type system the space complexity of the abstract machine. Additionally, we show how to capture also the time of the Space KAM, which is a reasonable time cost model, via minor changes to the type system.
Published: 2022
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12. The theory of call-by-value solvability

Author: Beniamino Accattoli, Giulio Guerrieri, Automatisation et ReprésenTation: fOndation du calcUl et de la déducTion (PARTOUT), Laboratoire d'informatique de l'École polytechnique [Palaiseau] (LIX), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), and University of Bath [Bath]
Subjects: call-by-value, intersection types, [INFO.INFO-LO]Computer Science [cs]/Logic in Computer Science [cs.LO], Safety, Risk, Reliability and Quality, solvability, Software
Abstract: International audience; The semantics of the untyped (call-by-name) lambda-calculus is a well developed field built around the concept of solvable terms, which are elegantly characterized in many different ways. In particular, unsolvable terms provide a consistent notion of meaningless term. The semantics of the untyped call-by-value lambda-calculus (CbV) is instead still in its infancy, because of some inherent difficulties but also because CbV solvable terms are less studied and understood than in call-by-name. On the one hand, we show that a carefully crafted presentation of CbV allows us to recover many of the properties that solvability has in call-by-name, in particular qualitative and quantitative characterizations via multi types. On the other hand, we stress that, in CbV, solvability plays a different role: identifying unsolvable terms as meaningless induces an inconsistent theory.
Published: 2022
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13. Coqlex: Generating Formally Verified Lexers

Author: Ouedraogo, Wendlasida, Scherer, Gabriel, Strassburger, Lutz, Automatisation et ReprésenTation: fOndation du calcUl et de la déducTion (PARTOUT), Laboratoire d'informatique de l'École polytechnique [Palaiseau] (LIX), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), INRIA Saclay - Ile-de-France, and OUEDRAOGO, Wendlasida
Subjects: FOS: Computer and information sciences, Computer Science - Programming Languages, [INFO] Computer Science [cs], Lexer, Tokenizer, Formal verification, Lexical analyzers, OCamllex, Compilers, Verbatim++, Regexp, Coq, [INFO]Computer Science [cs], Programming Languages (cs.PL)
Abstract: A compiler consists of a sequence of phases going from lexical analysis to code generation. Ideally, the formal verification of a compiler should include the formal verification of each component of the tool-chain. An example is the CompCert project, a formally verified C compiler, that comes with associated tools and proofs that allow to formally verify most of those components. However, some components, in particular the lexer, remain unverified. In fact, the lexer of Compcert is generated using OCamllex, a lex-like OCaml lexer generator that produces lexers from a set of regular expressions with associated semantic actions. Even though there exist various approaches, like CakeML or Verbatim++, to write verified lexers, they all have only limited practical applicability. In order to contribute to the end-to-end verification of compilers, we implemented a generator of verified lexers whose usage is similar to OCamllex. Our software, called Coqlex, reads a lexer specification and generates a lexer equipped with a Coq proof of its correctness. It provides a formally verified implementation of most features of standard, unverified lexer generators. The conclusions of our work are two-fold: Firstly, verified lexers gain to follow a user experience similar to lex/flex or OCamllex, with a domain-specific syntax to write lexers comfortably. This introduces a small gap between the written artifact and the verified lexer, but our design minimizes this gap and makes it practical to review the generated lexer. The user remains able to prove further properties of their lexer. Secondly, it is possible to combine simplicity and decent performance. Our implementation approach that uses Brzozowski derivatives is noticeably simpler than the previous work in Verbatim++ that tries to generate a deterministic finite automaton (DFA) ahead of time, and it is also noticeably faster thanks to careful design choices. We wrote several example lexers that suggest that the convenience of using Coqlex is close to that of standard verified generators, in particular, OCamllex. We used Coqlex in an industrial project to implement a verified lexer of Ada. This lexer is part of a tool to optimize safety-critical programs, some of which are very large. This experience confirmed that Coqlex is usable in practice, and in particular that its performance is good enough. Finally, we performed detailed performance comparisons between Coqlex, OCamllex, and Verbatim++. Verbatim++ is the state-of-the-art tool for verified lexers in Coq, and the performance of its lexer was carefully optimized in previous work by Egolf and al. (2022). Our results suggest that Coqlex is two orders of magnitude slower than OCamllex, but two orders of magnitude faster than Verbatim++. Verified compilers and other language-processing tools are becoming important tools for safety-critical or security-critical applications. They provide trust and replace more costly approaches to certification, such as manually reading the generated code. Verified lexers are a missing piece in several Coq-based verified compilers today. Coqlex comes with safety guarantees, and thus shows that it is possible to build formally verified front-ends.
Published: 2023

14. Energy-Aware Spreading Factor Selection in LoRaWAN Using Delayed-Feedback Bandits

Author: Navas, Renzo Efrain, Dandachi, Ghina, Hadjadj-Aoul, Yassine, Maillé, Patrick, Département Systèmes Réseaux, Cybersécurité et Droit du numérique (IMT Atlantique - SRCD), IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Self-prOtecting The futurE inteRNet (SOTERN), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-RÉSEAUX, TÉLÉCOMMUNICATION ET SERVICES (IRISA-D2), Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-Institut National de Recherche en Informatique et en Automatique (Inria)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-Institut National de Recherche en Informatique et en Automatique (Inria)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), mEasuRing and ManagIng Network operation and Economic (ERMINE), Inria Rennes – Bretagne Atlantique, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-RÉSEAUX, TÉLÉCOMMUNICATION ET SERVICES (IRISA-D2), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Institut National de Recherche en Informatique et en Automatique (Inria), Université de Rennes (UR), IFIP, and ANR-20-CE25-0011,INTELLIGENTSIA,Intelligence de la périphérie du réseau par des boucles d'apprentissage et la génération de données pour une automatisation du réseau basée sur l'inférence de ses états.(2020)
Subjects: reinforcement learning, IoT, ADR, Spreading Factor selection, Thompson sampling, LoRa, LoRaWAN, [INFO.INFO-NI]Computer Science [cs]/Networking and Internet Architecture [cs.NI], [INFO.INFO-PF]Computer Science [cs]/Performance [cs.PF], bandits, [INFO.INFO-LG]Computer Science [cs]/Machine Learning [cs.LG], energy consumption, LPWAN, Adaptive Data Rate, [INFO.INFO-ET]Computer Science [cs]/Emerging Technologies [cs.ET]
Abstract: International audience; LoRaWAN networks can involve large numbers of wireless devices relying on batteries to sense the environment and send data to gateways. A critical trade-off for transmission performance (packet delivery ratio) versus energy conservation (and hence, the device lifespan) appears when deciding the transmission parameters, in particular, the Spreading Factor (SF) to be used by each node. In this paper, we use lightweight reinforcement learning techniques, namely multi-armed bandits, for each node to select an appropriate SF, based on preferences regarding that trade-off. Unlike previous works on that topic, we relax some assumptions to aim at a realistic implementation: our solution does not assume immediate rewards, or that each device communicates with only one gateway. Additionally, we build explicit MAC commands for the method to work in practice and implement it in the ns-3 simulator using a state-of-the-art LoRaWAN module. We share the source code of our implementation and our simulation results. Those simulations show that when energy conservation is critical for IoT nodes, such lightweight learning algorithms outperform LoRaWAN's legacy Adaptive Data Rate algorithm, both in single- and multi-gateway scenarios.
Published: 2023

15. The Algebraic Weak Factorisation System for Delta Lenses

Author: Clarke, Bryce, Automatisation et ReprésenTation: fOndation du calcUl et de la déducTion (PARTOUT), Laboratoire d'informatique de l'École polytechnique [Palaiseau] (LIX), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-Inria Saclay - Ile de France, and Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)
Subjects: lens, monad, algebra for a monad, bidirectional transformation, algebraic weak factorisation system, FOS: Mathematics, Category Theory (math.CT), Mathematics - Category Theory, MSC classes:18A32, 18C15, 18A32, 18C15, [MATH]Mathematics [math]
Abstract: Delta lenses are functors equipped with a suitable choice of lifts, and are used to model bidirectional transformations between systems. In this paper, we construct an algebraic weak factorisation system whose R-algebras are delta lenses. Our approach extends a semi-monad for delta lenses previously introduced by Johnson and Rosebrugh, and generalises to any suitable category equipped with an orthogonal factorisation system and an idempotent comonad. We demonstrate how the framework of an algebraic weak factorisation system provides a natural setting for understanding the lifting operation of a delta lens, and also present an explicit description of the free delta lens on a functor., 14 pages + 2 page appendix, submitted to ACT 2023
Published: 2023

16. Study of high-quality superconducting FeSe single crystals: crossover in electronic transport from a metallic to an activated regime above 350 K

Author: S Karlsson, P Strobel, A Sulpice, C Marcenat, M Legendre, F Gay, S Pairis, O Leynaud, P Toulemonde, Matériaux, Rayonnements, Structure (NEEL - MRS), Institut Néel (NEEL), 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), Magnétisme et Supraconductivité (NEEL - MagSup), Consortium de Recherches pour l'Emergence des Technologies Avancées (CRETA), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Laboratoire de Transport Electronique Quantique et Supraconductivité (LaTEQS), PHotonique, ELectronique et Ingénierie QuantiqueS (PHELIQS), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), X'Press : diffraction et hautes pressions (NEEL - X'Press), Automatisation & caractérisation (NEEL - AUTOCARAC), Croissance Cristalline et MicroAnalyse (NEEL - C2MA), Matériaux, Rayonnements, Structure (MRS), 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), Magnétisme et Supraconductivité (MagSup), X'Press (X'Press), Automatisation et Caractérisation (AUTOCARAC), and Optique et microscopies (POM)
Subjects: Superconductivity, Materials science, Condensed matter physics, Doping, Metals and Alloys, 02 engineering and technology, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Metal, Crystal, [PHYS.COND.CM-S]Physics [physics]/Condensed Matter [cond-mat]/Superconductivity [cond-mat.supr-con], Electrical resistivity and conductivity, Agglomerate, visual_art, 0103 physical sciences, Materials Chemistry, Ceramics and Composites, visual_art.visual_art_medium, Electrical and Electronic Engineering, 010306 general physics, 0210 nano-technology, Stoichiometry, ComputingMilieux_MISCELLANEOUS, Eutectic system
Abstract: We report the growth of high quality FeSe single crystals using chemical vapor transport based on an AlCl3/KCl eutectic and their physical properties were fully characterized by magnetic, transport and specific heat measurements. Their critical superconducting temperature at T c ~ 8.7 K (width < 0.7 K) and structural tetragonal–orthorhombic transition at T s ~ 85–90 K confirm the values already reported in the literature for similar crystals. In addition, the non-variation of T s under high magnetic field (up to 14 T) determined by magnetic and specific heat measurements indicates that spin fluctuations are not directly involved in the structural transition. Finally, high temperature electrical resistivity measurements up to 600 K evidence a maximum around 350 K. The origin of this crossover from metallic behavior at low temperature to a semiconducting-like regime at high temperature is discussed and could be associated with a change of carrier density above 350 K. On the other hand, the tentative growth of Te-substituted Fe(Se1−x Te x ) crystals using the same growth method resulted in crystals with x(Te) < 1% and a slightly lower T c compared to pure FeSe ones, which may be related to transition metal–chalcogen non-stoichiometry. Finally, Cr doping at the Fe site was also attempted. In contrast to previous reports in the literature, our results suggest that Cr does not substitute for Fe in the FeSe crystal but agglomerates in Cr-rich (Cr,Fe)Se2 inclusions, and T c of these (Fe1−x Cr x )Se crystals is not increased, but slightly decreased in comparison to stoichiometric FeSe crystals.
Published: 2015
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17. Impact of the driver’s visual engagement on situation awareness and takeover quality

Author: Paul Marti, Christophe Jallais, Arnaud Koustanaï, Anne Guillaume, Franck Mars, Laboratoire des Sciences du Numérique de Nantes (LS2N), Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-École Centrale de Nantes (Nantes Univ - ECN), Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes université - UFR des Sciences et des Techniques (Nantes univ - UFR ST), Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ), Laboratoire d'Accidentologie de Biomécanique et d'Etude du Comportement Humain, RENAULT, Laboratoire Ergonomie et Sciences Cognitives pour les Transports (TS2-LESCOT ), Université Gustave Eiffel, and ANR-16-CE22-0007,AutoConduct,Adaptation de la stratégie d'automatisation des véhicules autonomes (niveaux 3-4) aux besoins et à l'état des conducteurs en conditions réelles(2016)
Subjects: Automated driving, [SCCO.PSYC]Cognitive science/Psychology, Automotive Engineering, Transportation, Situation awareness, Non-driving task, Taker-over request, Human factors, Applied Psychology, Civil and Structural Engineering
Abstract: International audience; During automated driving (SAE Level 3), drivers can delegate control of the vehicle and monitoring of the road to an automated system. They may then devote themselves to tasks other than driving and gradually lose situational awareness (SA). This could res ult in difficulty in regaining control of the vehicle when the automated system requires it. In this simulator study, the level of SA was manipulated through the time spent performing a nondriving task (NDRT), which alternated with phases where the driver could monitor the driving scene, prior to a critical takeover request (TOR). The SA at the time of TOR, the visual behaviour after TOR, and the takeover quality were analysed. The results showed that monitoring the road just before the TOR allowed the development of limited perception of the driving situation, which only partially compensated for the lack of a consolidated mental model of the situation. The quality of the recovery, assessed through the number of collisions, was consistent with the level of development of SA. The analysis of visual behaviour showed that engagement in the non-driving task at the time of TOR induced a form of perseverance in consulting the interface where the task was displayed, to the detriment of checking the mirrors. These results underline the importance of helping the driver to restore good SA well in advance of a TOR.
Published: 2022
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18. A positive perspective on term representation: Extended paper

Author: Miller, Dale, Wu, Jui-Hsuan, Laboratoire d'informatique de l'École polytechnique [Palaiseau] (LIX), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Automatisation et ReprésenTation: fOndation du calcUl et de la déducTion (PARTOUT), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-Inria Saclay - Ile de France, and Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)
Subjects: sharing, [INFO.INFO-LO]Computer Science [cs]/Logic in Computer Science [cs.LO], Term representation, Focused proof systems
Abstract: International audience; We use the focused proof system LJF as a framework for describing term structures and substitution. Since the proof theory of LJF does not pick a canonical polarization for primitive types, two different approaches to term representation arise. When primitive types are given the negative polarity, LJF proofs encode terms as tree-like structures in a familiar fashion. In this situation, cut elimination also yields the familiar notion of substitution. On the other hand, when primitive types are given the positive polarity, LJF proofs yield a structure in which explicit sharing of term structures is possible. Such a representation of terms provides an explicit method for sharing term structures. In this setting, cut elimination yields a different notion of substitution. We illustrate these two approaches to term representation by applying them to the encoding of untyped λ-terms. We also exploit concurrency theory techniques-namely traces and simulation-to compare untyped λ-terms using such different structuring disciplines.
Published: 2023

19. Backtracking reference stores

Author: Noûs, Camille, Scherer, Gabriel, Laboratoire Cogitamus, Automatisation et ReprésenTation: fOndation du calcUl et de la déducTion (PARTOUT), Laboratoire d'informatique de l'École polytechnique [Palaiseau] (LIX), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Timothy Bourke, and Delphine Demange
Subjects: [INFO]Computer Science [cs]
Abstract: National audience; François Pottier's unionFind library is parameterized over an underlying store of mutable references, and provides the usual references, transactional reference stores (for rolling back some changes in case of higher-level errors), and persistent reference stores. We extend this library with a new implementation of backtracking reference stores, to get a Union-Find implementation that efficiently supports arbitrary backtracking and also subsumes the transactional interface. Our backtracking reference stores are not specific to unionFind, they can be used to build arbitrary backtracking data structures. The natural implementation, using a journal to record all writes, provides amortized-constant-time operations with a space overhead linear in the number of store updates. A refined implementation reduces the memory overhead to be linear in the number of store cells updated, and gives performance that match non-backtracking references in practice.
Published: 2023

20. Determination of the magnetocaloric entropy change in the presence of phase separation and metastability: The case of Eu0.58Sr0.42MnO3

Author: V. Hardy, D. Fruchart, B. Zawilski, F. Guillou, Laboratoire de cristallographie et sciences des matériaux (CRISMAT), École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC), Micro et NanoMagnétisme (MNM), Institut Néel (NEEL), 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), Automatisation et Caractérisation (AUTOCARAC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Micro et NanoMagnétisme (NEEL - MNM), and Automatisation & caractérisation (NEEL - AUTOCARAC)
Subjects: [PHYS]Physics [physics], Manganite, Materials science, Condensed matter physics, Magnetic refrigeration, Magnetocaloric effect, Thermodynamics, Condensed Matter Physics, First order, Magnetic phase transition, Electronic, Optical and Magnetic Materials, Metastability, ComputingMilieux_MISCELLANEOUS
Abstract: International audience; The magnetocaloric effect (MCE) in the manganite Eu0.58Sr0.42MnO3 was derived by different methods, in a field range very sensitive to the phenomenon of phase separation. It turns out that a strong scatter in the MCE features was observed. When the applied field is less than the field required to complete the transition, it is found that the MCE can be strongly overestimated by “standard” indirect measurements. A way to properly estimate the MCE around a first order transition in the presence of phase separation and metastability is proposed.
Published: 2014
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21. Non-universality of artificial frustrated spin systems

Author: Olivier Fruchart, Nicolas Rougemaille, Benjamin Canals, Michel Hehn, Alexander Grimm, François Montaigne, Edouard Wagner, Ioan-Augustin Chioar, Daniel Lacour, Théorie de la Matière Condensée (TMC), Institut Néel (NEEL), 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), Micro et NanoMagnétisme (MNM), Automatisation et Caractérisation (AUTOCARAC), Institut Jean Lamour (IJL), Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), MNM, TMC, TMC - Théorie de la Matière Condensée, Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF), MNM - Micro et NanoMagnétisme, AUTOCARAC - Automatisation et Caractérisation, and Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Condensed Matter - Mesoscale and Nanoscale Physics, Condensed matter physics, Monte Carlo method, FOS: Physical sciences, 02 engineering and technology, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Nanomagnet, Electronic, Optical and Magnetic Materials, Universality (dynamical systems), Spin ice, Dipole, Magnetization, Quantum mechanics, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Mesoscale and Nanoscale Physics (cond-mat.mes-hall), 0103 physical sciences, Magnetic frustration, Condensed Matter::Strongly Correlated Electrons, Magnetic force microscope, 010306 general physics, 0210 nano-technology
Abstract: Magnetic frustration effects in artificial kagome arrays of nanomagnets with out-of-plane magnetization are investigated using Magnetic Force Microscopy and Monte Carlo simulations. Experimental and theoretical results are compared to those found for the artificial kagome spin ice, in which the nanomagnets have in-plane magnetization. In contrast with what has been recently reported, we demonstrate that long range (i.e. beyond nearest-neighbors) dipolar interactions between the nanomagnets cannot be neglected when describing the magnetic configurations observed after demagnetizing the arrays using a field protocol. As a consequence, there are clear limits to any universality in the behavior of these two artificial frustrated spin systems. We provide arguments to explain why these two systems show striking similarities at first sight in the development of pairwise spin correlations., 7 pages, 6 figures
Published: 2014
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22. A Survey of the Proof-Theoretic Foundations of Logic Programming

Author: Dale Miller, Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria), Laboratoire d'informatique de l'École polytechnique [Palaiseau] (LIX), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Automatisation et ReprésenTation: fOndation du calcUl et de la déducTion (PARTOUT), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-Inria Saclay - Ile de France, and Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)
Subjects: FOS: Computer and information sciences, Computer Science - Logic in Computer Science, F.3.2, F.4.1, Computer science, Semantics (computer science), 0102 computer and information sciences, Mathematical proof, computer.software_genre, 01 natural sciences, Theoretical Computer Science, Artificial Intelligence, Computer Science::Logic in Computer Science, Structural proof theory, 0101 mathematics, Logic programming, Functional programming, [INFO.INFO-PL]Computer Science [cs]/Programming Languages [cs.PL], Computer Science - Programming Languages, Programming language, 010102 general mathematics, Classical logic, [INFO.INFO-LO]Computer Science [cs]/Logic in Computer Science [cs.LO], Linear logic, Logic in Computer Science (cs.LO), TheoryofComputation_MATHEMATICALLOGICANDFORMALLANGUAGES, Computational Theory and Mathematics, 010201 computation theory & mathematics, Hardware and Architecture, Proof theory, Computer Science::Programming Languages, computer, Software, Programming Languages (cs.PL)
Abstract: Several formal systems, such as resolution and minimal model semantics, provide a framework for logic programming. In this paper, we will survey the use of structural proof theory as an alternative foundation. Researchers have been using this foundation for the past 35 years to elevate logic programming from its roots in first-order classical logic into higher-order versions of intuitionistic and linear logic. These more expressive logic programming languages allow for capturing stateful computations and rich forms of abstractions, including higher-order programming, modularity, and abstract data types. Term-level bindings are another kind of abstraction, and these are given an elegant and direct treatment within both proof theory and these extended logic programming languages. Logic programming has also inspired new results in proof theory, such as those involving polarity and focused proofs. These recent results provide a high-level means for presenting the differences between forward-chaining and backward-chaining style inferences. Anchoring logic programming in proof theory has also helped identify its connections and differences with functional programming, deductive databases, and model checking., To appear in Theory and Practice of Logic Programming (TPLP)
Published: 2021
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23. Lightweight learning algorithms for massive IoT and analysis of their performance

Author: Dandachi, Ghina, Hadjadj-Aoul, Yassine, Maillé, Patrick, Navas, Renzo Efrain, mEasuRing and ManagIng Network operation and Economic (ERMINE), Inria Rennes – Bretagne Atlantique, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-RÉSEAUX, TÉLÉCOMMUNICATION ET SERVICES (IRISA-D2), Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-Institut National de Recherche en Informatique et en Automatique (Inria)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-Institut de Recherche en Informatique et Systèmes Aléatoires (IRISA), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université de Bretagne Sud (UBS)-École normale supérieure - Rennes (ENS Rennes)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT), Département Systèmes Réseaux, Cybersécurité et Droit du numérique (IMT Atlantique - SRCD), IMT Atlantique (IMT Atlantique), Dependability Interoperability and perfOrmance aNalYsiS Of networkS (DIONYSOS), Laboratoire des sciences et techniques de l'information, de la communication et de la connaissance (Lab-STICC), École Nationale d'Ingénieurs de Brest (ENIB)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Institut Mines-Télécom [Paris] (IMT)-Centre National de la Recherche Scientifique (CNRS)-Université Bretagne Loire (UBL)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT), INRIA Rennes - Bretagne Atlantique and University of Rennes 1, France, and ANR-20-CE25-0011,INTELLIGENTSIA,Intelligence de la périphérie du réseau par des boucles d'apprentissage et la génération de données pour une automatisation du réseau basée sur l'inférence de ses états.(2020)
Subjects: [INFO.INFO-PF]Computer Science [cs]/Performance [cs.PF], [INFO]Computer Science [cs]
Abstract: Executive summary We address in this deliverable parameters optimization as well as the automation of devices configuration in massive IoT LoRaWAN scenarios. The utilization of automation techniques for devices configuration is a crucial evolution in IoT LoRa radio access in the way for network virtualization and automation. The challenges in LoRa radio access networks virtualization consists on partitioning the resources between different services and devices that are connecting in an ALOHA-like access. We will investigate how to perform an automatic orchestration of radio resources between different devices. In particular, we will focus on a reducing the overhead required to ensure a good functioning of the automated devices configuration. We intend to (i) develop strategies enabling IoT devices automated configuration (ii) explore possible strategies enabling to follow a certain goal, such as maximize the energy efficiency, or the reliability, represented here by the Packet delivery ratio, and (iii) prepare a platform for service differentiation of different IoT slices.
Published: 2022

24. Large scale magnesium hydride tank coupled with an external heat source

Author: Salvatore Miraglia, Philippe Marty, Baptiste Delhomme, Patricia de Rango, Daniel Fruchart, Cécile Raufast, Bartosz Zawilski, Maria Bacia, Consortium de Recherches pour l'Emergence des Technologies Avancées (CRETA), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Laboratoire des Écoulements Géophysiques et Industriels [Grenoble] (LEGI), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF), Matériaux, Rayonnements, Structure (MRS), 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), X'Press (X'Press), Automatisation et Caractérisation (AUTOCARAC), Micro et NanoMagnétisme (MNM), European Project: 32895,NESSHY, Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS), Matériaux, Rayonnements, Structure (NEEL - MRS), 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), X'Press : diffraction et hautes pressions (NEEL - X'Press), Automatisation & caractérisation (NEEL - AUTOCARAC), and Micro et NanoMagnétisme (NEEL - MNM)
Subjects: Exothermic reaction, 020209 energy, Magnesium hydride, Energy Engineering and Power Technology, 02 engineering and technology, 7. Clean energy, Sink (geography), [SPI.MECA.MEFL]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Fluids mechanics [physics.class-ph], chemistry.chemical_compound, Hydrogen storage, Thermal conductivity, Heat exchanger, Thermal, 0202 electrical engineering, electronic engineering, information engineering, [PHYS.MECA.MEFL]Physics [physics]/Mechanics [physics]/Fluid mechanics [physics.class-ph], geography, geography.geographical_feature_category, Renewable Energy, Sustainability and the Environment, Chemistry, Sorption kinetics, Metallurgy, Sorption, Cycling, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Fuel Technology, Heat exchanges, Chemical engineering, Metal Hydride Tank, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [PHYS.MECA.THER]Physics [physics]/Mechanics [physics]/Thermics [physics.class-ph], [SPI.MECA.THER]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Thermics [physics.class-ph], 0210 nano-technology
Abstract: International audience; The experimental study of a large scale magnesium hydride tank (10 kg) is presented. In order to enhance thermal exchanges and improve storage time, the MgH2 powder has been compacted with 10 wt.% of Expanded Natural Graphite. An efficient heat exchanger has been designed to transfer the heat from the endo/exothermic sorption reactions to an external heat source/sink through a high temperature heat transfer fluid. An improvement of the loading and discharging time along the first hydrogenation cycles is observed owing to material thermal conductivity modifications. The properties of the cycled material have been studied in order to understand this evolution of the tank behavior.
Published: 2012
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25. Calorimetric investigation of the magnetocaloric effect in Ni45Co5Mn37.5In12.5

Author: D. Bourgault, Pierre Courtois, Francois Guillou, Philippe Plaindoux, L. Porcar, Vincent Hardy, Laboratoire de cristallographie et sciences des matériaux (CRISMAT), École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC), Institut Laue-Langevin (ILL), ILL, Thermodynamique et biophysique des petits systèmes (TPS), 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), Automatisation et Caractérisation (AUTOCARAC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Thermodynamique et biophysique des petits systèmes (NEEL - TPS), 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), and Automatisation & caractérisation (NEEL - AUTOCARAC)
Subjects: Acoustics and Ultrasonics, Chemistry, Thermodynamics, 02 engineering and technology, Calorimetry, Atmospheric temperature range, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Heat capacity, Isothermal process, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Differential scanning calorimetry, 0103 physical sciences, Magnetic refrigeration, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], 010306 general physics, 0210 nano-technology, Adiabatic process, Single crystal, ComputingMilieux_MISCELLANEOUS
Abstract: A calorimetric investigation of a Ni45Co5Mn37.5In12.5 single crystal has been carried out by combining differential scanning calorimetry (DSC) and heat capacity (C) measurements. The martensitic transition showing a first-order character spread over a wide temperature range, a specific measuring technique of C(T) has been developed. This method—based on a time-resolved analysis of successive heating pulses—was found to yield an entropy change at the transition (ΔS tr) that is very close to that derived from DSC. To investigate the magnetocaloric effect, both the isothermal entropy change ΔS T and the adiabatic temperature change ΔT ad were derived from heat capacity curves recorded in a series of magnetic fields up to 7 T. The maximum values of ΔS T (T, B) were observed to be in accordance with those determined from the Maxwell equation. Furthermore, maximum values of ΔT ad(T, B) resulting from the application of 2 T, 5 T and 7 T were found to be equal to −2.3 K, −6.1 K and −9.4 K, respectively.
Published: 2012
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26. Effect of the isoelectronic substitution of Sb for As on the magnetic and structural properties of LaFe(As1−xSbx)O

Author: G. Garbarino, Jacques Marcus, F. Levy-Bertrand, Manuel Núñez-Regueiro, André Sulpice, Thierry Klein, Vivian Nassif, Sébastien Pairis, Thomas Hansen, C. Marcenat, P. Toulemonde, S. J. E. Carlsson, Magnétisme et Supraconductivité (NEEL - MagSup), Institut Néel (NEEL), 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), Service de Physique Statistique, Magnétisme et Supraconductivité (SPSMS - UMR 9001), Institut Nanosciences et Cryogénie (INAC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Automatisation & caractérisation (NEEL - AUTOCARAC), Croissance Cristalline et MicroAnalyse (NEEL - C2MA), European Synchrotron Radiation Facility (ESRF), Institut Laue-Langevin (ILL), CRG & Grands instruments (NEEL - CRG), Matériaux, Rayonnements, Structure (NEEL - MRS), ANR-09-BLAN-0211,TETRAFER(2009), Magnétisme et Supraconductivité (MagSup), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Automatisation et Caractérisation (AUTOCARAC), Optique et microscopies (POM), ILL, CRG et Grands Instruments (CRG), and Matériaux, Rayonnements, Structure (MRS)
Subjects: Materials science, Neutron diffraction, FOS: Physical sciences, 02 engineering and technology, 01 natural sciences, 74.70.Xa, 75.30.Fv, 61.05.fm, Superconductivity (cond-mat.supr-con), 0103 physical sciences, Antiferromagnetism, 010306 general physics, Superconductivity, Condensed Matter - Materials Science, Condensed matter physics, Atomic force microscopy, Condensed Matter - Superconductivity, Materials Science (cond-mat.mtrl-sci), Order (ring theory), Substitution (algebra), 021001 nanoscience & nanotechnology, Condensed Matter Physics, 3. Good health, Electronic, Optical and Magnetic Materials, [PHYS.COND.CM-S]Physics [physics]/Condensed Matter [cond-mat]/Superconductivity [cond-mat.supr-con], Crystallography, High pressure, Crystallite, 0210 nano-technology
Abstract: The antiferromagnetic order and structural distortion in the LaFe(As1-xSbx)O system have been investigated by powder neutron diffraction and physical properties measurements. Polycrystalline samples of LaFe(As1-xSbx)O (x, 21 pages, 6 figures
Published: 2011
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27. The contribution of x-ray specular reflectometry to the oxygen-induced magnetic properties in Pt/Co/AlOx

Author: H. Garad, L. Ortega, A. Y. Ramos, J. Marcus, F. Gay, F. Fettar, S. Auffret, B. Rodmacq, B. Dieny, Surfaces, Interfaces et Nanostructures (NEEL - SIN), Institut Néel (NEEL), 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), X'Press : diffraction et hautes pressions (NEEL - X'Press), Matériaux, Rayonnements, Structure (NEEL - MRS), Automatisation & caractérisation (NEEL - AUTOCARAC), SPINtronique et TEchnologie des Composants (SPINTEC), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Surfaces, Interfaces et Nanostructures (SIN), 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), X'Press (X'Press), Matériaux, Rayonnements, Structure (MRS), and Automatisation et Caractérisation (AUTOCARAC)
Subjects: Flux pinning, Materials science, Silicon, Magnetoresistance, Annealing (metallurgy), Analytical chemistry, General Physics and Astronomy, chemistry.chemical_element, 02 engineering and technology, 01 natural sciences, PACS : 75.60.Nt 75.50.Vv 72.20.My 73.43.Qt, Nuclear magnetic resonance, flux pinning, Hall effect, 0103 physical sciences, magnetoresistance, Specular reflection, platinum, coercive force, 010306 general physics, Reflectometry, silicon, magnetic annealing, aluminium compounds, Coercivity, 021001 nanoscience & nanotechnology, cobalt, alumina, chemistry, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], 0210 nano-technology, silicon compounds
Abstract: 3 pages; International audience; Two key parameters were analyzed in Si/SiO/Pt/Co/AlOx: the oxidation time of the Al layer resulting in AlOx, and the ex situ annealing temperatures varied in the 15 and 55 s and 20, 300, and 450 °C ranges, respectively. For intermediate annealing temperatures (∼300 °C), the quantitative analysis of specular reflectometry data shows that the progressive oxidation of layers by increasing the oxidation time goes along with an improvement of the homogeneity of the alumina layer. This outcome casts new light on the temperature dependence of magnetic properties of the samples. The remarkable temperature variation of the coercive field, extracted from extraordinary Hall effects in the 5-300 K range, is associated with structural change due to Co-oxygen bondings, which leads to strong pinning of Co spins in the low temperature regime.
Published: 2011
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28. Influence of thermal fluctuations on the Nernst signal in superconducting (K,Ba)BiO3 single crystals

Author: Klein, Thierry, Pribulova, Z., Piquerel, Raoul, Cercellier, Hervé, Marcus, Jacques, Marcenat, C., Magnétisme et Supraconductivité (MagSup), 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), Centre of Low Temperature Physics IEP SAS (CLTP), Slovak Academy of Science [Bratislava] (SAS), Circuits électroniques quantiques Alpes (QuantECA), Automatisation et Caractérisation (AUTOCARAC), Service de Physique Statistique, Magnétisme et Supraconductivité (SPSMS - UMR 9001), Institut Nanosciences et Cryogénie (INAC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Magnétisme et Supraconductivité (NEEL - MagSup), 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), Circuits électroniques quantiques Alpes (NEEL - QuantECA), and Automatisation & caractérisation (NEEL - AUTOCARAC)
Subjects: Quantitative Biology::Subcellular Processes, [PHYS.COND.CM-S]Physics [physics]/Condensed Matter [cond-mat]/Superconductivity [cond-mat.supr-con], Condensed Matter::Superconductivity, 74.40.−n, 74.25.Op, supraconductivité
Abstract: International audience; We report on the Nernst effect, specific heat and transportmeasurements performed in high quality (K,Ba)BiO3 single crystals close to optimal doping (Tc ∼ 31 K). We show that a nonzero Nernst effect remains visible well above the upper critical field unambiguously deduced from the onset of the specific heat anomaly. This finite Nernst signal is attributed to fluctuations of the amplitude of the order parameter in a region where the free energy is smaller than kBT . Despite the absence of any vortex liquid phase (and hence of any significant phase fluctuations), the field and temperature dependence of the Nernst coefficient is very similar to the one obtained in electron-doped cuprates.
Published: 2011
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29. Influence of benzene on the Ni3Fe nanocrystalline compound formation by wet mechanical alloying: An investigation combining DSC, X-ray diffraction, mass and IR spectrometries

Author: P. Plaindoux, Olivier Isnard, N. Jumate, B.V. Neamţu, Ionel Chicinaş, C. Vagner, Matériaux, Rayonnements, Structure (MRS), 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), Universitatea Tehnica din Cluj-Napoca (UTCN), Laboratoire Chimie Provence (LCP), Centre National de la Recherche Scientifique (CNRS)-Université de Provence - Aix-Marseille 1-Institut de Chimie du CNRS (INC), Automatisation et Caractérisation (AUTOCARAC), Matériaux, Rayonnements, Structure (NEEL - MRS), 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), Université de Provence - Aix-Marseille 1-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Automatisation & caractérisation (NEEL - AUTOCARAC)
Subjects: 010302 applied physics, Thermogravimetric analysis, Materials science, Analytical chemistry, Infrared spectroscopy, 02 engineering and technology, Calorimetry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Nanocrystalline material, Thermogravimetry, Differential scanning calorimetry, 0103 physical sciences, X-ray crystallography, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], General Materials Science, 0210 nano-technology, Thermal analysis
Abstract: International audience; Nanocrystalline Ni3Fe powders were obtained via wet mechanical alloying using benzene as surfactant. The differential scanning calorimetry (DSC) measurements showed the presence of an exothermic peak which does not correspond to any phase transformation or phase formation as was proved by X-ray diffraction measurements. The exothermic peak was observed neither for the dry milled samples nor for the wet milled and subsequently annealed powders at 350 degrees C for 4 h. The infra-red (IR) spectra registered for the wet milled samples showed a series of vibration bands corresponding to C6H6 and also to a series of fragments resulting from benzene decomposition. The results obtained by IR investigation were confirmed by thermogravimetry and mass spectrometry (TG + MS) investigations. The main fragments resulting from the benzene decomposition on the surface of the nanocrystalline Ni3Fe powders are: CO2, CO and C. The evolution of the particle size distribution versus the milling time has been determined for the wet mechanical milling process of nanocrystalline Ni3Fe powders. The DSC analysis reveals a displacement of the exothermic peak onset towards lower temperatures and an increase of the surface of this peak attributed to the changes in the particles specific surface and to the quantity of benzene added in the milling experiments.
Published: 2011
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30. Direct observation of Oersted-field-induced magnetization dynamics in magnetic nanostripes

Author: C. Tieg, Stefania Pizzini, Jan Vogel, Laurent Ranno, Julio Camarero, Fausto Sirotti, E. Jiménez, Michal Urbánek, Vincent Cros, Nicolas Rougemaille, V. Uhlíř, Gilles Gaudin, E. Wagner, Olivier Fruchart, Micro et NanoMagnétisme (MNM), Institut Néel (NEEL), 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), Unité mixte de physique CNRS/Thales (UMPhy CNRS/THALES), Centre National de la Recherche Scientifique (CNRS)-THALES, Departamento de Fisica de la Materia Condensada [Madrid] (FMC), Facultad de Ciencas [Madrid], Universidad Autonoma de Madrid (UAM)-Universidad Autonoma de Madrid (UAM), Institute of Physical Engineering, Brno University of Technology [Brno] (BUT), SPINtronique et TEchnologie des Composants (SPINTEC), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), European Synchrotron Radiation Facility (ESRF), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Automatisation et Caractérisation (AUTOCARAC), ANR-07-NANO-0034,DYNAWALL,Magnetic domain wall dynamics induced by spin polarised current(2007), Micro et NanoMagnétisme (NEEL - MNM), THALES [France]-Centre National de la Recherche Scientifique (CNRS), Universidad Autónoma de Madrid (UAM)-Universidad Autónoma de Madrid (UAM), Automatisation & caractérisation (NEEL - AUTOCARAC), and UAM. Departamento de Física de la Materia Condensada
Subjects: Field (physics), FOS: Physical sciences, magnetization dynamics, 02 engineering and technology, 01 natural sciences, spin torque, Magnetization, Condensed Matter::Materials Science, 0103 physical sciences, 010306 general physics, Anisotropy, magnetic nanowires, Physics, Condensed Matter - Materials Science, Magnetization dynamics, spin-valves, Condensed matter physics, Oersted, Física, Materials Science (cond-mat.mtrl-sci), 021001 nanoscience & nanotechnology, Condensed Matter Physics, Electronic, Optical and Magnetic Materials, Magnetic field, 75.70.Ak, 75.60.Jk, 07.85.Qe, 75.50.Bb, Photoemission electron microscopy, Domain wall (magnetism), time-resolved PEEM, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], 0210 nano-technology
Abstract: We have used time-resolved x-ray photoemission electron microscopy to investigate the magnetization dynamics induced by nanosecond current pulses in NiFe/Cu/Co nanostripes. A large tilt of the NiFe magnetization in the direction transverse to the stripe is observed during the pulses. We show that this effect cannot be quantitatively understood from the amplitude of the Oersted field and the shape anisotropy. High frequency oscillations observed at the onset of the pulses are attributed to precessional motion of the NiFe magnetization about the effective field. We discuss the possible origins of the large magnetization tilt and the potential implications of the static and dynamic effects of the Oersted field on current-induced domain wall motion in such stripes., Comment: Published in Phys. Rev. B 83, 020406 (2011) (Rapid Communications)
Published: 2011
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31. Surface effects in a semiconductor photonic nanowire and spectral stability of an embedded single quantum dot

Author: Jean-Philippe Poizat, Emmanuel Dupuy, Édouard Wagner, Yann-Michel Niquet, N. S. Malik, Joël Bleuse, Mathieu Munsch, Gilles Nogues, Signe Seidelin, Inah Yeo, Julien Claudon, Jean-Michel Gérard, Alexia Auffèves, Nanophysique et Semiconducteurs (NPSC), 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), Institut Nanosciences et Cryogénie (INAC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Automatisation et Caractérisation (AUTOCARAC), Nano-Optique et Forces (NOF), Nanophysique et Semiconducteurs (NEEL - NPSC), 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), Automatisation & caractérisation (NEEL - AUTOCARAC), and Nano-Optique et Forces (NEEL - NOF)
Subjects: Photon, Materials science, III-V semiconductors, Physics and Astronomy (miscellaneous), Nanowire, Physics::Optics, FOS: Physical sciences, 02 engineering and technology, 01 natural sciences, semiconductor quantum dots, [PHYS.QPHY]Physics [physics]/Quantum Physics [quant-ph], 0103 physical sciences, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Laser power scaling, 010306 general physics, Quantum optics, Quantum Physics, Condensed Matter - Mesoscale and Nanoscale Physics, business.industry, 021001 nanoscience & nanotechnology, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, gallium arsenide, indium compounds, Semiconductor, surface charging, nanowires, Quantum dot, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], Optoelectronics, Photonics, 0210 nano-technology, business, 78.67.Hc, 78.67.Uh, 73.40.-c, Quantum Physics (quant-ph), Excitation
Abstract: International audience; We evidence the influence of surface effects for InAs quantum dots embedded into GaAs photonic nanowires used as efficient single photon sources. We observe a continuous temporal drift of the emission energy that is an obstacle to resonant quantum optics experiments at the single photon level. We attribute the drift to the sticking of oxygen molecules onto the wire, which modifies the surface charge and hence the electric field seen by the quantum dot. The influence of temperature and excitation laser power on this phenomenon is studied. Most importantly, we demonstrate a proper treatment of the nanowire surface to suppress the drift.
Published: 2011
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32. A System of Interaction and Structure III: The Complexity of BV and Pomset Logic

Author: Nguyễn, Lê Thành Dũng, Straßburger, Lutz, Straßburger, Lutz, une expédition cartographique entre le lambda-calcul, la logique, et la combinatoire - - LambdaComb2021 - ANR-21-CE48-0017 - AAPG2021 - VALID, Community of mathematics and fundamental computer science in Lyon - - MILYON2010 - ANR-10-LABX-0070 - LABX - VALID, Preuves et Langages (PLUME), Laboratoire de l'Informatique du Parallélisme (LIP), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS), Automatisation et ReprésenTation: fOndation du calcUl et de la déducTion (PARTOUT), Laboratoire d'informatique de l'École polytechnique [Palaiseau] (LIX), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), ANR-21-CE48-0017,LambdaComb,une expédition cartographique entre le lambda-calcul, la logique, et la combinatoire(2021), and ANR-10-LABX-0070,MILYON,Community of mathematics and fundamental computer science in Lyon(2010)
Subjects: FOS: Computer and information sciences, Computer Science - Logic in Computer Science, [INFO.INFO-LO] Computer Science [cs]/Logic in Computer Science [cs.LO], system BV, dicographs, relation webs, [INFO.INFO-LO]Computer Science [cs]/Logic in Computer Science [cs.LO], deep inference, proof nets, pomset logic, cographs, seriesparallel orders, Logic in Computer Science (cs.LO)
Abstract: Pomset logic and BV are both logics that extend multiplicative linear logic (with Mix) with a third connective that is self-dual and non-commutative. Whereas pomset logic originates from the study of coherence spaces and proof nets, BV originates from the study of series-parallel orders, cographs, and proof systems. Both logics enjoy a cut-admissibility result, but for neither logic can this be done in the sequent calculus. Provability in pomset logic can be checked via a proof net correctness criterion and in BV via a deep inference proof system. It has long been conjectured that these two logics are the same. In this paper we show that this conjecture is false. We also investigate the complexity of the two logics, exhibiting a huge gap between the two. Whereas provability in BV is NP-complete, provability in pomset logic is $\Sigma_2^p$-complete. We also make some observations with respect to possible sequent systems for the two logics.
Published: 2022

33. Boxroot, fast movable GC roots for a better FFI

Author: Munch-Maccagnoni, Guillaume, Scherer, Gabriel, Gallinette : vers une nouvelle génération d'assistant à la preuve (GALLINETTE), Inria Rennes – Bretagne Atlantique, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-Laboratoire des Sciences du Numérique de Nantes (LS2N), Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-École Centrale de Nantes (Nantes Univ - ECN), Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes université - UFR des Sciences et des Techniques (Nantes univ - UFR ST), Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Nantes Université (Nantes Univ), Automatisation et ReprésenTation: fOndation du calcUl et de la déducTion (PARTOUT), Laboratoire d'informatique de l'École polytechnique [Palaiseau] (LIX), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), and Benoît Montagu
Subjects: [INFO.INFO-PL]Computer Science [cs]/Programming Languages [cs.PL], [INFO.INFO-LO]Computer Science [cs]/Logic in Computer Science [cs.LO]
Abstract: International audience; We propose a new API and implementation for managing garbage collector (GC) roots for the OCaml foreign-function interface (FFI), which offers:- better performance than existing APIs (local or global roots);- efficient support for OCaml 5 with a more multicore-friendly design, with per-domain data structures;- a reasoning based on resource-management idioms, enabling an easier FFI for Rust.Our contributions include a C library called Boxroot which is already in use in several OCaml-Rust interfacing libraries.We believe that this approach generalizes beyond OCaml, to other FFI situations where a language with GC interacts with a language without pervasive GC, especially those that emphasize move semantics for resource handling (typically C++ or Rust); or even to future language explorations in mixing memory management techniques.
Published: 2022

34. Un usage de la réduction paresseuse forte pour OCaml

Author: Scherer, Gabriel, Courant, Nathanaëlle, Automatisation et ReprésenTation: fOndation du calcUl et de la déducTion (PARTOUT), Laboratoire d'informatique de l'École polytechnique [Palaiseau] (LIX), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Langages de programmation : systèmes de types, concurrence, preuve de programme (CAMBIUM), Collège de France (CdF (institution))-Inria de Paris, and Benoit Montagu
Subjects: [INFO]Computer Science [cs]
Abstract: International audience; We present a use-case for strong call-by-need reduction motivated not by a proof assistant, but by the normalization of module "shapes" in the OCaml compiler for tooling purposes.
Published: 2022

35. An introduction to enriched cofunctors

Author: Clarke, Bryce, Di Meglio, Matthew, Automatisation et ReprésenTation: fOndation du calcUl et de la déducTion (PARTOUT), Laboratoire d'informatique de l'École polytechnique [Palaiseau] (LIX), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), and University of Edinburgh
Subjects: cofunctor, lens, MSC 18D20, 18N10, FOS: Mathematics, enriched category theory, Category Theory (math.CT), Mathematics - Category Theory, 18D20, 18N10, double category, [MATH.MATH-CT]Mathematics [math]/Category Theory [math.CT]
Abstract: Cofunctors are a kind of map between categories which lift morphisms along an object assignment. In this paper, we introduce cofunctors between categories enriched in a distributive monoidal category. We define a double category of enriched categories, enriched functors, and enriched cofunctors, whose horizontal and vertical 2-categories have 2-cells given by enriched natural transformations between functors and cofunctors, respectively. Enriched lenses are defined as a compatible enriched functor and enriched cofunctor pair; weighted lenses, which were introduced by Perrone, are precisely lenses enriched in weighted sets. Several other examples are also studied in detail., 16 pages
Published: 2022

36. Combinatorial Proofs for Constructive Modal Logic

Author: Acclavio, Matteo, Straßburger, Lutz, University of Luxembourg [Luxembourg], Automatisation et ReprésenTation: fOndation du calcUl et de la déducTion (PARTOUT), Laboratoire d'informatique de l'École polytechnique [Palaiseau] (LIX), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), and École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)
Subjects: combinatorial proofs proof equivalence arena nets constructive modal logic, arena nets, combinatorial proofs, [INFO.INFO-LO]Computer Science [cs]/Logic in Computer Science [cs.LO], constructive modal logic, proof equivalence
Abstract: International audience; Combinatorial proofs form a syntax-independent presentation of proofs, originally proposed by Hughes for classical propositional logic. In this paper we present a notion of combinatorial proofs for the constructive modal logics CK and CD, we show soundness and completeness of combinatorial proofs by translation from and to sequent calculus proofs, and we discuss the notion of proof equivalence enforced by these translations.
Published: 2022

37. Normalization Without Syntax

Author: Heijltjes, Willem B., Hughes, Dominic J. D., Straßburger, Lutz, University of Bath [Bath], University of California [Berkeley] (UC Berkeley), University of California (UC), Automatisation et ReprésenTation: fOndation du calcUl et de la déducTion (PARTOUT), Laboratoire d'informatique de l'École polytechnique [Palaiseau] (LIX), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Inria associate team COMPRONOM, and Felty, Amy P.
Subjects: combinatorial proofs, Proof theory, Theory of computation → Lambda calculus, [INFO.INFO-LO]Computer Science [cs]/Logic in Computer Science [cs.LO], Curry-Howard, proof nets, intuitionistic logic, lambda-calculus, TheoryofComputation_MATHEMATICALLOGICANDFORMALLANGUAGES, Theory of computation → Proof theory, TheoryofComputation_LOGICSANDMEANINGSOFPROGRAMS, Computer Science::Logic in Computer Science, Curry–Howard, Software
Abstract: We present normalization for intuitionistic combinatorial proofs (ICPs) and relate it to the simply-typed lambda-calculus. We prove confluence and strong normalization. Combinatorial proofs, or "proofs without syntax", form a graphical semantics of proof in various logics that is canonical yet complexity-aware: they are a polynomial-sized representation of sequent proofs that factors out exactly the non-duplicating permutations. Our approach to normalization aligns with these characteristics: it is canonical (free of permutations) and generic (readily applied to other logics). Our reduction mechanism is a canonical representation of reduction in sequent calculus with closed cuts (no abstraction is allowed below a cut), and relates to closed reduction in lambda-calculus and supercombinators. While we will use ICPs concretely, the notion of reduction is completely abstract, and can be specialized to give a reduction mechanism for any representation of typed normal forms., LIPIcs, Vol. 228, 7th International Conference on Formal Structures for Computation and Deduction (FSCD 2022), pages 19:1-19:19
Published: 2022
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38. Disorder effects in pnictides : a tunneling spectroscopy study

Author: Dimitri Roditchev, William Sacks, Vincent Dubost, Pierre Toulemonde, Sven Lange, A Sulpice, François Debontridder, J Marcus, Y. Noat, T. Cren, Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Matériaux, Rayonnements, Structure (MRS), Institut Néel (NEEL), 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), Automatisation et Caractérisation (AUTOCARAC), Magnétisme et Supraconductivité (MagSup), 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), Matériaux, Rayonnements, Structure (NEEL - MRS), Automatisation & caractérisation (NEEL - AUTOCARAC), Magnétisme et Supraconductivité (NEEL - MagSup), and 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)
Subjects: Superconductivity, Materials science, Condensed matter physics, Rietveld refinement, Scattering, Condensed Matter - Superconductivity, FOS: Physical sciences, 02 engineering and technology, PACS : PACS 74.50.+r Tunneling phenomena, point contacts, weak links, Josephson effects, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Superconductivity (cond-mat.supr-con), Tunnel effect, [PHYS.QPHY]Physics [physics]/Quantum Physics [quant-ph], Pairing, Condensed Matter::Superconductivity, 0103 physical sciences, Quasiparticle, General Materials Science, 010306 general physics, 0210 nano-technology, Spectroscopy, Quantum tunnelling
Abstract: We present the synthesis and the tunneling spectroscopy study of superconducting FeSe0.5Te0.5 (Tc = 14 K), SmFeAsO0.85 (Tc = 45 K) and SmFeAsO0.9F0.1 (Tc = 52 K). The samples were characterized by Rietveld refinement of X-ray diffraction patterns and transport measurements. Tunneling experiments on FeSe0.5Te0.5 revealed a single superconducting gap of ~1 meV in BCS-like tunnelling conductance spectra. In SmFeAsO0.85 and SmFeAsO0.9F0.1 however, more complex spectra were observed characterized by two gap-like structures at ~4 meV and ~10 meV. These spectra are qualitatively understood assuming a two-band superconductor with a 's\pm' order parameter. We show that depending on the sign relation between the pairing amplitudes in the two bands, the interband quasiparticle scattering has a crucial effect on the shape of the tunneling spectra. Detailed analysis of the tunneling spectroscopy data supports the 's\pm' model, but single-gap spectra found in FeSe0.5Te0.5 are more compatible with a disorder-induced 's'-wave gap, due to the Se-Te substitution., 11 pages, 7 figures
Published: 2010
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39. Magnetic and dielectric properties in the langasite-type compounds : A3BFe3D2O14 with A=Ba, Sr, Ca, B=Ta, Nb, Sb and D=Ge, Si

Author: Marty, Karol, Bordet, Pierre, Simonet, Virginie, Loire, Mickael, Ballou, Rafik, Darie, Céline, Kljun, Jakob, Bonville, Pierre, Isnard, Olivier, Lejay, Pascal, Zawilski, Bartosz, Simon, Charles, Matériaux, Rayonnements, Structure (MRS), Institut Néel (NEEL), 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), Magnétisme et Supraconductivité (MagSup), Institut Rayonnement Matière de Saclay (IRAMIS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Cristaux Massifs (CrisMass), Automatisation et Caractérisation (AUTOCARAC), Laboratoire de cristallographie et sciences des matériaux (CRISMAT), École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC), ANR-06-BLAN-0187,Langasites,Les langasites : de la frustration magnétique à l'optique non-linéaire(2006), Matériaux, Rayonnements, Structure (NEEL - MRS), Magnétisme et Supraconductivité (NEEL - MagSup), Croissance Cristalline et MicroAnalyse (NEEL - C2MA), Automatisation & caractérisation (NEEL - AUTOCARAC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), and Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: langasite, Condensed Matter - Strongly Correlated Electrons, Strongly Correlated Electrons (cond-mat.str-el), heavy fermions, dielectric properties, PACS numbers: 75.25.+z, 71.27.+a, magnetic frustration, FOS: Physical sciences, Strongly correlated electron systems, [PHYS.COND.CM-SCE]Physics [physics]/Condensed Matter [cond-mat]/Strongly Correlated Electrons [cond-mat.str-el], helical magnetic order
Abstract: International audience; The Fe-based langasites are the first reported compounds presenting a magnetic ordering in this rich family, besides being well known for piezo-electric properties and optical activity. The structural, magnetic and dielectric properties of the Fe langasite compounds, with various substitution of non-magnetic cations, have been studied with x-ray and neutron diffraction, magnetostatic measurements, Mössbauer spectroscopy, and dielectric measurements. The title compounds (trigonal, space group P321) display a helical magnetic order with signatures of frustration below TN ~24- 35 K where an anomaly of the dielectric permittivity is observed. The influence of the cationic substitutions and the nature of the magnetoelectric coupling is hereafter addressed.
Published: 2010
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40. Investigation of metallic/oxide interfaces in Pt/Co/AlOx trilayers by hard x-ray reflectivity

Author: P. Plaindoux, H. Garad, B. Zawilski, Bernard Dieny, F. Fettar, Stéphane Auffret, Bernard Rodmacq, Luc Ortega, A.Y. Ramos, Surfaces, Interfaces et Nanostructures (SIN), 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), X'Press (X'Press), Matériaux, Rayonnements, Structure (MRS), Automatisation et Caractérisation (AUTOCARAC), SPINtronique et TEchnologie des Composants (SPINTEC), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut de Recherche Interdisciplinaire de Grenoble (IRIG), Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Surfaces, Interfaces et Nanostructures (NEEL - SIN), 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), X'Press : diffraction et hautes pressions (NEEL - X'Press), Matériaux, Rayonnements, Structure (NEEL - MRS), and Automatisation & caractérisation (NEEL - AUTOCARAC)
Subjects: Materials science, oxidation, perpendicular magnetic anisotropy, Analytical chemistry, Oxide, chemistry.chemical_element, 02 engineering and technology, 01 natural sciences, Metal, chemistry.chemical_compound, reflectometry X-ray chemical analysis, Hall effect, 0103 physical sciences, Magnetic layered films, Electrical and Electronic Engineering, 010306 general physics, Magnetic structure, Condensed matter physics, 021001 nanoscience & nanotechnology, Electronic, Optical and Magnetic Materials, X-ray reflectivity, Magnetic anisotropy, chemistry, metal-insulator structures, visual_art, visual_art.visual_art_medium, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], X-ray measurements, 0210 nano-technology, Platinum, Cobalt
Abstract: International audience; X-ray reflectivity (XRR) is used to determine the oxidation front at the nanometer scale in sputtered perpendicular semi tunnel junctions, as the form Pt/Co/AlOx, by varying the oxidation time tOx of the capping layer. From XRR simulations, we show that the nature of the stack is gradually defined according to the value of tOx. For low tOx values (
Published: 2009
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41. Mapping the superconducting condensate surrounding a vortex in superconducting V3Si using a superconducting MgB2 tip in a scanning tunneling microscope

Author: Bergeal, N., Noat, Yves, Cren, Tristan, Proslier, T., Dubost, Vincent, Debontridder, François, Zimmers, A., Roditchev, D., Sacks, W., Marcus, Jacques, Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-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), Automatisation et Caractérisation (AUTOCARAC), Institut Néel (NEEL), 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), 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), and Automatisation & caractérisation (NEEL - AUTOCARAC)
Subjects: Condensed Matter::Quantum Gases, [PHYS.COND.CM-S]Physics [physics]/Condensed Matter [cond-mat]/Superconductivity [cond-mat.supr-con], Condensed Matter::Superconductivity, NB3SN
Abstract: International audience; As shown recently [Proslier , Europhys. Lett. 73, 962 (2006)], it is possible to map the superconducting (SC) condensate by measuring locally the Josephson tunneling current. We apply this technique to image the vortex lattice in V3Si which is used as the simplest example of a spatially varying quantum condensate. The Josephson scanning tunneling microscope (JSTM) maps revealed the vortex lattice with the Josephson effect being present outside the vortices and disappearing progressively toward the vortex core. The characteristic length scales of a vortex observed in the Josephson regime are compared to the ones obtained in the quasiparticle regime. We demonstrate that the JSTM allows a nanometer scale resolution of the SC condensate that may be applied to inhomogeneous phases such as high-T-c superconductors.
Published: 2008
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42. Anomalous electric-field effect and glassy behaviour in granular aluminium: electron glass?

Author: T. Grenet, J. Delahaye, M. Sabra, F. Gay, Magnétisme et Supraconductivité (MagSup), 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), Laboratoire de Physique des Matériaux et des Surfaces (LPMS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine, Automatisation et Caractérisation (AUTOCARAC), Magnétisme et Supraconductivité (NEEL - MagSup), 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), Automatisation & caractérisation (NEEL - AUTOCARAC), Université de Cergy Pontoise (UCP), and Université Paris-Seine-Université Paris-Seine-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
Subjects: Materials science, Condensed matter physics, Oxide, Coulomb blockade, chemistry.chemical_element, Field effect, 02 engineering and technology, Dielectric, Electron, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Condensed Matter::Soft Condensed Matter, chemistry.chemical_compound, chemistry, Electrical resistance and conductance, Aluminium, 0103 physical sciences, Relaxation (physics), [PHYS.COND.CM-DS-NN]Physics [physics]/Condensed Matter [cond-mat]/Disordered Systems and Neural Networks [cond-mat.dis-nn], 010306 general physics, 0210 nano-technology
Abstract: the proceedings editor does not allow on-line preprints (!) link to the paper on the editor site: http://onlinelibrary.wiley.com/doi/10.1002/pssc.200777561/abstract; International audience; We briefly review our study of non-equilibrium phenomena observed in the electrical conductance of insulating granular aluminium thin films at low temperature. In MOS like structures, with granular aluminium channels, an anomalous field effect and its slow relaxation have been studied in some detail, the phenomenology of which is very similar to the one also observed in indium oxide. The interpretation of the experimental findings is discussed. To date, in granular systems, the present experiments can qualitatively be interpreted along two different lines. One (the "extrinsic" scenario) relies on a slow polarisation in the dielectric surrounding the metallic islands. The other one is a purely electronic mechanism: the formation of an electron Coulomb glass in the granular met al. Some experimental facts seem difficult to reconcile with the extrinsic scenario, but more selective experiments and/or quantitative theoretical predictions are still needed to definitely distinguish between the two scenarii.
Published: 2008
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43. Field and angular dependence of the Sommerfeld coefficient in Al-doped MgB2 single crystals

Author: Pribulova, Z., Klein, Thierry, Marcus, Jacques, Marcenat, C., S. Park, M., Lee, H.S., Lee, H.G., Lee, S.I., Magnétisme et Supraconductivité (MagSup), 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), Automatisation et Caractérisation (AUTOCARAC), Service de Physique Statistique, Magnétisme et Supraconductivité (SPSMS - UMR 9001), Institut Nanosciences et Cryogénie (INAC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), NVCRICS, Pohang University of Science and Technology (POSTECH), Magnétisme et Supraconductivité (NEEL - MagSup), 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), and Automatisation & caractérisation (NEEL - AUTOCARAC)
Subjects: [PHYS.COND.CM-S]Physics [physics]/Condensed Matter [cond-mat]/Superconductivity [cond-mat.supr-con], Condensed Matter::Superconductivity, 74.50.+r,74.25.Op, 74.72.-h, supraconductivité
Abstract: International audience; The angular and field dependence of the Sommerfeld coefficient = lim Cel /T T→0 Cel being the electronic contribution to the specific heat has been measured in Al-doped MgB2 single crystals for x=0, x=0.1, and x 0.2 . We show that the decomposition previously introduced to describe H, where is the angle between the applied field and the c axis in pure samples Phys. Rev. Lett. 98, 137001 2007 is well adapted to doped samples: e.g., the contribution of the band to the specific heat is proportional to B/Bc2 whereas the contribution of the band is isotropic but highly nonlinear in field. We hence present the evolution of the coherence lengths of the two bands and corresponding Fermi velocities with doping.
Published: 2007
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44. New reactor dedicated to in operando studies of model catalysts by means of surface x-ray diffraction and grazing incidence small angle x-ray scattering

Author: M.C. Saint-Lager, O. Geaymond, R. Baudoing-Savois, Pierre Taunier, Olivier Ulrich, Aude Bailly, Stéphanie Garaudée, François Rieutord, Gilles Perroux, Olivier Tissot, P. Dolle, Jean-Sébastien Micha, Sabine Douillet, Sylvain Cuccaro, Surfaces, Interfaces et Nanostructures (SIN), Institut Néel (NEEL), 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), SERAS (SERAS), Epitaxie et couches minces (EpiCM), Automatisation et Caractérisation (AUTOCARAC), CRG et Grands Instruments (CRG), Cryogénie (Cryo), Service de Physique des Matériaux et Microstructures (SP2M - UMR 9002), Institut Nanosciences et Cryogénie (INAC), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), 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), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Surfaces, Interfaces et Nanostructures (NEEL - SIN), Service Etudes et Réalisation d'Appareillages Scientifiques (NEEL - SERAS), Epitaxie et couches minces (NEEL- EpiCM), Automatisation & caractérisation (NEEL - AUTOCARAC), CRG & Grands instruments (NEEL - CRG), and Cryogénie (NEEL - Cryo)
Subjects: Diffraction, Materials science, Surface Properties, Analytical chemistry, 02 engineering and technology, 7. Clean energy, 01 natural sciences, Electron spectroscopy, Sensitivity and Specificity, Catalysis, Specimen Handling, Optics, X-Ray Diffraction, 0103 physical sciences, Scattering, Small Angle, [PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det], 010306 general physics, Instrumentation, Auger electron spectroscopy, Low-energy electron diffraction, Scattering, business.industry, Reproducibility of Results, Partial pressure, Equipment Design, 021001 nanoscience & nanotechnology, Equipment Failure Analysis, Electron diffraction, X-ray crystallography, 0210 nano-technology, business
Abstract: International audience; A new experimental setup has been developed to enable in situ studies of catalyst surfaces during chemical reactions by means of surface x-ray diffraction (SXRD) and grazing incidence small angle x-ray scattering. The x-ray reactor chamber was designed for both ultrahigh-vacuum (UHV) and reactive gas environments. A laser beam heating of the sample was implemented; the sample temperature reaches 1100 K in UHV and 600 K in the presence of reactive gases. The reactor equipment allows dynamical observations of the surface with various, perfectly mixed gases at controlled partial pressures. It can run in two modes: as a bath reactor in the pressure range of 1-1000 mbars and as a continuous flow cell for pressure lower than 10−3 mbar. The reactor is connected to an UHV preparation chamber also equipped with low energy electron diffraction and Auger spectroscopy. This setup is thus perfectly well suited to extend in situ studies to more complex surfaces, such as epitaxial films or supported nanoparticles. It offers the possibility to follow the chemically induced changes of the morphology, the structure, the composition, and growth processes of the model catalyst surface during exposure to reactive gases. As an example the Pd8Ni92(110) surface structure was followed by SXRD under a few millibars of hydrogen and during butadiene hydrogenation while the reaction was monitored by quadrupole mass spectrometry. This experiment evidenced the great sensitivity of the diffracted intensity to the subtle interaction between the surface atoms and the gas molecules.
Published: 2007
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45. Metal-insulator transition and superconductivity in boron-doped diamond

Author: Julien Pernot, Christophe Marcenat, Clas Persson, Jacques Marcus, Etienne Bustarret, J. Kačmarčik, C. Cytermann, Frederik Gustafsson, Thierry Klein, Franck Omnès, Bo E. Sernelius, Philipp Achatz, A. Ferreira Sa Silva, Magnétisme et Supraconductivité (MagSup), 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), Semi-conducteurs à large bande interdite (SC2G), Slovakian Academy of sciences - Institut of Experimental Physics (SAS), Slovakian Academy of sciences, Département de Recherche Fondamentale sur la Matière Condensée (DRFMC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Automatisation et Caractérisation (AUTOCARAC), Department of Physics, Chemistry and Biology [Linköping] (IFM), Linköping University (LIU), Department of Materials Science and Engineering, KTH (KTH), Department of Materials Science and Engineering, KTH, Instituto de Física da Universidade Federal da Bahia (UFBA), Universidade Federal da Bahia (UFBA), Solid State Institute, Solid State Institute, Technion, Magnétisme et Supraconductivité (NEEL - MagSup), 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), Semi-conducteurs à large bande interdite (NEEL - SC2G), and Automatisation & caractérisation (NEEL - AUTOCARAC)
Subjects: superconducting transition temperature, superconducting thin films, 02 engineering and technology, 01 natural sciences, Variable-range hopping, hopping conduction, Pseudopotential, diamond, Condensed Matter::Superconductivity, Naturvetenskap, 0103 physical sciences, Coulomb, metal-insulator transition, Metal–insulator transition, superconducting materials, 010306 general physics, Boron doped diamond, Superconductivity, Physics, Condensed matter physics, superconductivity, Hall effect, Order (ring theory), 021001 nanoscience & nanotechnology, Condensed Matter Physics, Electronic, Optical and Magnetic Materials, [PHYS.COND.CM-S]Physics [physics]/Condensed Matter [cond-mat]/Superconductivity [cond-mat.supr-con], Boron concentration, electron-phonon interactions, superconducting transitions, 71.30.+h, 71.20.Nr, 74.25.Fy, boron, Natural Sciences, 0210 nano-technology
Abstract: We report on a detailed analysis of the transport properties and superconducting critical temperatures of boron-doped diamond films grown along the {100} direction. The system presents a metal-insulator transition (MIT) for a boron concentration (nB) on the order of nc~4.5×1020 cm−3, in excellent agreement with numerical calculations. The temperature dependence of the conductivity and Hall effect can be well described by variable range hopping for nBnc) present a superconducting transition at low temperature. The zero-temperature conductivity 0 deduced from fits to the data above the critical temperature (Tc) using a classical quantum interference formula scales as 0(nB/nc−1) with ~1. Large Tc values (0.4 K) have been obtained for boron concentration down to nB/nc~1.1 and Tc surprisingly mimics a (nB/nc−1)1/2 law. Those high Tc values can be explained by a slow decrease of the electron-phonon coupling parameter and a corresponding drop of the Coulomb pseudopotential µ* as nBnc. Original Publication:T. Klein, P. Achatz, J. Kacmarcik, C. Marcenat, F. Gustafsson, J. Marcus, E. Bustarret, J. Pernot, F. Omnes, Bo Sernelius, C. Persson, A. Ferreira da Silva and C. Cytermann, Metal-insulator transition and superconductivity in boron-doped diamond, 2007, Physical Review B. Condensed Matter and Materials Physics, (75), 165313.http://dx.doi.org/10.1103/PhysRevB.75.165313Copyright: American Physical Societyhttp://www.aps.org/
Published: 2007
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46. Anisotropy of the Sommerfeld Coefficient in Magnesium Diboride Single Crystals

Author: F. Levy, Thierry Klein, H.G. Lee, Setsuko Tajima, Sung-Ik Lee, C. Marcenat, Jacques Marcus, M. S. Park, Byeongwon Kang, Z. Pribulova, S.-I. Lee, Magnétisme et Supraconductivité (MagSup), Institut Néel (NEEL), 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), Automatisation et Caractérisation (AUTOCARAC), Service de Physique Statistique, Magnétisme et Supraconductivité (SPSMS - UMR 9001), Institut Nanosciences et Cryogénie (INAC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), NVCRICS, Pohang University of Science and Technology (POSTECH), Department of Physics, Osaka University [Osaka], Superconductivity Research Laboratory (SRL), International Superconductivity Technology Center (ISTEC), Magnétisme et Supraconductivité (NEEL - MagSup), and Automatisation & caractérisation (NEEL - AUTOCARAC)
Subjects: Superconductivity, Physics, Field (physics), Condensed matter physics, Isotropy, General Physics and Astronomy, Field dependence, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, [PHYS.COND.CM-S]Physics [physics]/Condensed Matter [cond-mat]/Superconductivity [cond-mat.supr-con], Magnetization, chemistry.chemical_compound, chemistry, 0103 physical sciences, Magnesium diboride, 010306 general physics, 0210 nano-technology, Anisotropy, Critical field
Abstract: The anisotropic field dependence of the Sommerfeld coefficient gamma has been measured down to B--0 by combining specific heat and Hall probe magnetization measurements in MgB2 single crystals. We find that gamma(B,theta) is the sum of two contributions arising from the sigma and pi band, respectively. We show that gammasigma(B,theta)=B/Bc2(theta) where Bc2(theta)=Bc2ab/sqrt[sin2theta+Gamma2cos2theta] with Gamma approximately 5.4 (theta being the angle between the applied field and the c axis) and gammapi(B,theta)=gammapi(B)=B/Bpi(B). The "critical field" of the pi band Bpi is fully isotropic but field dependent increasing from approximately 0.25 T for Bor =0.1 T up to 3 T approximately Bc2c for B--3 T. Because of the coupling of the two bands, superconductivity survives in the pi band up to 3 T but is totally destroyed above for any orientation of the field.
Published: 2007
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47. A tunable Fabry–Pérot quantum Hall interferometer in graphene

Author: Corentin Déprez, Louis Veyrat, Hadrien Vignaud, Goutham Nayak, Kenji Watanabe, Takashi Taniguchi, Frédéric Gay, Hermann Sellier, Benjamin Sacépé, Nano-Electronique Quantique et Spectroscopie (QuNES), Institut Néel (NEEL), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), National Institute for Materials Science (NIMS), and Automatisation et Caractérisation (AUTOCARAC)
Subjects: Biomedical Engineering, Anyon, Bioengineering, 02 engineering and technology, Quantum Hall effect, 010402 general chemistry, Interference (wave propagation), 7. Clean energy, 01 natural sciences, Article, law.invention, law, Astronomical interferometer, General Materials Science, Electrical and Electronic Engineering, [PHYS.COND.CM-MSQHE]Physics [physics]/Condensed Matter [cond-mat]/Mesoscopic Systems and Quantum Hall Effect [cond-mat.mes-hall], Physics, Condensed Matter - Mesoscale and Nanoscale Physics, Graphene, business.industry, Landau quantization, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Atomic and Molecular Physics, and Optics, 0104 chemical sciences, Coherence length, [PHYS.COND.CM-S]Physics [physics]/Condensed Matter [cond-mat]/Superconductivity [cond-mat.supr-con], Interferometry, Optoelectronics, 0210 nano-technology, business
Abstract: Electron interferometry with quantum Hall edge channels holds promise for probing and harnessing exotic exchange statistics of non-Abelian anyons. In semiconductor heterostructures, however, quantum Hall interferometry has proven challenging and often obscured by charging effects. Here we show that high-mobility monolayer graphene equipped with a series of gate-tunable quantum point contacts that act as electron beam-splitters provides a model system to perform Fabry-P\'{e}rot quantum Hall interferometry. We observe high-visibility Aharonov-Bohm interference free of charging effects and widely tunable through electrostatic gating or magnetic field, in remarkable agreement with theory. A coherence length of $\mathbf{10 \,\mu m}$ at a temperature of $0.02$ K allows us to further achieve coherently-coupled double Fabry-P\'{e}rot interferometry. Our results open a new avenue for quantum Hall interferometry and the exploitation of topological excitations for quantum computation., Comment: Revised main text
Published: 2021
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48. Étude de l’état attentionnel des conducteurs en conduite automatisée à partir des stratégies visuelles

Author: Marti, Paul, Perception, Action, Cognition pour la Conception et l’Ergonomie (LS2N - équipe PACCE), Laboratoire des Sciences du Numérique de Nantes (LS2N), Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Institut Mines-Télécom [Paris] (IMT)-Institut Mines-Télécom [Paris] (IMT)-École Centrale de Nantes (Nantes Univ - ECN), Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes université - UFR des Sciences et des Techniques (Nantes univ - UFR ST), Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Nantes Université (Nantes Univ)-Nantes Université - pôle Sciences et technologie, Nantes Université (Nantes Univ)-Institut National de Recherche en Informatique et en Automatique (Inria)-Centre National de la Recherche Scientifique (CNRS)-IMT Atlantique (IMT Atlantique), Nantes Université (Nantes Univ), Université de Nantes, Franck Mars, Anne Guillaume, and ANR-16-CE22-0007,AutoConduct,Adaptation de la stratégie d'automatisation des véhicules autonomes (niveaux 3-4) aux besoins et à l'état des conducteurs en conditions réelles(2016)
Subjects: automated driving, stratégies visuelles, visual strategies, mindwandering, reprise en main, [SHS.PSY]Humanities and Social Sciences/Psychology, sortie de boucle, out-of-the-loop, vagabondage de la pensée, takeover, conduite automatisée
Abstract: This work concerned the assessment of drivers’ attentional state in highly automated vehicle. A specific attention had been placed on the analysis of driver’s visual strategies. The first two experiments dealt on the link between distraction, visual strategies and takeover quality. To that end, divers had to realize non-driving activities during automated driving and had to deal with a non-planned takeover in obstacle avoidance situation. Results showed that there was an effect of the gaze location at the time of the takeover request but also an effect of the development of situational awareness on the takeover quality. The last experiment looked at the effect of different automation modes on driver inattention in the form of mindwandering. The evolution of mindwandering over time has been estimated by modeling the driver’s visual strategies. Results showed that mindwandering increased strongly to reach high levels very quickly and then fluctuated around a stable trend. These results are discussed in the context of the development of driver monitoring systems for autonomous vehicle.; Ce travail a porté sur l'évaluation de l'état attentionnel de conducteurs à bord d'un véhicule hautement automatisé. Un accent particulier a été mis sur l'analyse des stratégies visuelles du conducteur. Les deux premières expérimentations ont porté sur le lien entre distraction, stratégies visuelles et qualité de la reprise en main. Pour ce faire, les conducteurs ont réalisé des activités non liées à la conduite pendant une phase de conduite autonome et ont dû faire face à une demande de reprise en main non planifiée dans une situation d'évitement d'obstacle. Les résultats montrent qu'il existe un effet de la localisation du regard au moment de la demande de reprise en main mais également du niveau de l’élaboration de la conscience de la situation sur la qualité de la reprise en main. La dernière expérimentation s'est intéressée à l'effet de différentes modalités d'automatisation sur l'inattention du conducteur, prenant la forme d'un vagabondage de la pensée. L'évolution du vagabondage au fil du temps a été estimé en modélisant les stratégies visuelles des conducteurs. Les résultats montrent que le vagabondage augmente très fortement pour atteindre des niveaux élevés très rapidement puis fluctue autour d'une tendance stable. Ces résultats sont discutés dans la perspective du développement des outils d'évaluation de l'état du conducteur à bord des véhicules autonomes.
Published: 2022

49. Exponentials as Substitutions and the Cost of Cut Elimination in Linear Logic

Author: Beniamino Accattoli, Automatisation et ReprésenTation: fOndation du calcUl et de la déducTion (PARTOUT), Laboratoire d'informatique de l'École polytechnique [Palaiseau] (LIX), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), and École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)
Subjects: FOS: Computer and information sciences, Computer Science - Logic in Computer Science, TheoryofComputation_MATHEMATICALLOGICANDFORMALLANGUAGES, Computer Science - Programming Languages, TheoryofComputation_LOGICSANDMEANINGSOFPROGRAMS, [INFO.INFO-LO]Computer Science [cs]/Logic in Computer Science [cs.LO], Logic in Computer Science (cs.LO), Programming Languages (cs.PL)
Abstract: This paper introduces the exponential substitution calculus (ESC), a new presentation of cut elimination for IMELL, based on proof terms and building on the idea that exponentials can be seen as explicit substitutions. The idea in itself is not new, but here it is pushed to a new level, inspired by Accattoli and Kesner's linear substitution calculus (LSC). One of the key properties of the LSC is that it naturally models the sub-term property of abstract machines, that is the key ingredient for the study of reasonable time cost models for the $\lambda$-calculus. The new ESC is then used to design a cut elimination strategy with the sub-term property, providing the first polynomial cost model for cut elimination with unconstrained exponentials. For the ESC, we also prove untyped confluence and typed strong normalization, showing that it is an alternative to proof nets for an advanced study of cut elimination., Comment: LMCS submission for the special issue of LICS 2022
Published: 2022
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50. From axioms to synthetic inference rules via focusing

Author: Sonia Marin, Dale Miller, Elaine Pimentel, Marco Volpe, University of Birmingham [Birmingham], Automatisation et ReprésenTation: fOndation du calcUl et de la déducTion (PARTOUT), Laboratoire d'informatique de l'École polytechnique [Palaiseau] (LIX), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS)-Inria Saclay - Ile de France, Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria), Department of Computer science [University College of London] (UCL-CS), University College of London [London] (UCL), and Universität Osnabrück - Osnabrück University
Subjects: Logic, [INFO.INFO-LO]Computer Science [cs]/Logic in Computer Science [cs.LO]
Abstract: International audience; An important application of focused variants of Gentzen's sequent calculus proof rules is the construction of (possibly) large synthetic inference rules. This paper examines the synthetic inference rules that arise when using theories composed of bipolars, and we do this in both classical and intuitionistic logics. A key step in transforming a formula into synthetic inference rules involves attaching a polarity to atomic formulas and some logical connectives. Since there are different choices in how polarity is assigned, it is possible to produce different synthetic inference rules for the same formula. We show that this flexibility allows for the generalization of different approaches for transforming axioms into sequent rules present in the literature. We finish the paper showing how to apply these results to organize the proof theory of labeled sequent systems for several propositional modal logics.
Published: 2022
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