Author: "Fabrice Scheurer" / Topic: 01 natural sciences - Searchworks@Jio Institute Digital Library Search Results

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1. Ultralow-temperature device dedicated to soft X-ray magnetic circular dichroism experiments

Author: Philippe Ohresser, Florian Leduc, B. Gobaut, Giulia Serrano, B. Muller, Roberta Sessoli, Loïc Joly, Andrea Cornia, Matteo Mannini, M.-A. Arrio, Fabrice Scheurer, E. Lhotel, Guy Schmerber, Lorenzo Poggini, Edwige Otero, Weicheng Li, Jean-Paul Kappler, Ph. Sainctavit, Fadi Choueikani, Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), CFD Lab [Montréal], Department of Mechanical Engineering [Montréal], McGill University = Université McGill [Montréal, Canada]-McGill University = Université McGill [Montréal, Canada], Groupe de spectrométrie moléculaire et atmosphérique (GSMA), Université de Reims Champagne-Ardenne (URCA)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Università degli Studi di Firenze = University of Florence [Firenze] (UNIFI), 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 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]), Università degli Studi di Modena e Reggio Emilia (UNIMORE), Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Muséum national d'Histoire naturelle (MNHN)-Institut de recherche pour le développement [IRD] : UR206-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), and Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique
Subjects: Nuclear and High Energy Physics, Materials science, Absorption spectroscopy, Magnetism, Instrumentation, Astrophysics::High Energy Astrophysical Phenomena, 02 engineering and technology, Radiation, 010402 general chemistry, 01 natural sciences, law.invention, Optics, soft X-rays, law, ultralow-temperature, ComputingMilieux_MISCELLANEOUS, business.industry, Magnetic circular dichroism, XMCD, 021001 nanoscience & nanotechnology, Research Papers, Synchrotron, 0104 chemical sciences, Magnetic field, Beamline, magnetism, Physics::Accelerator Physics, [PHYS.COND.CM-SCE]Physics [physics]/Condensed Matter [cond-mat]/Strongly Correlated Electrons [cond-mat.str-el], 0210 nano-technology, business
Abstract: A new ultralow-temperature setup dedicated to soft X-ray absorption spectroscopy and X-ray magnetic circular dichroism experiments is described. Two experiments, performed on the DEIMOS beamline (SOLEIL synchrotron), demonstrate the outstanding performances of this new platform, particularly with regard to the lowest achievable temperature under X-ray irradiation (T = 220 mK)., A new ultralow-temperature setup dedicated to soft X-ray absorption spectroscopy and X-ray magnetic circular dichroism (XMCD) experiments is described. Two experiments, performed on the DEIMOS beamline (SOLEIL synchrotron), demonstrate the outstanding performance of this new platform in terms of the lowest achievable temperature under X-ray irradiation (T = 220 mK), the precision in controlling the temperature during measurements as well as the speed of the cooling-down and warming-up procedures. Moreover, owing to the new design of the setup, the eddy-current power is strongly reduced, allowing fast scanning of the magnetic field in XMCD experiments; these performances lead to a powerful device for X-ray spectroscopies on synchrotron-radiation beamlines facilities.
Published: 2018
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2. Magnetic phase and magneto-resistive effects in vanadium oxide epitaxial nanoclusters

Author: Bohdan Kundys, Hicham Majjad, Corinne Ulhaq-Bouillet, D. Halley, Jean-Francois Dayen, Brice Kengni-Zanguim, Joseph Uzan, Philippe Ohresser, Fabrice Scheurer, Loïc Joly, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)
Subjects: 010302 applied physics, Materials science, Physics and Astronomy (miscellaneous), Spintronics, Condensed matter physics, Vanadium, chemistry.chemical_element, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Vanadium oxide, Nanoclusters, Condensed Matter::Materials Science, chemistry, Ferromagnetism, Phase (matter), 0103 physical sciences, Condensed Matter::Strongly Correlated Electrons, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], 0210 nano-technology, Superparamagnetism, Spin canting
Abstract: International audience; The metal-insulator transition and the original magnetic phase that appear in vanadium oxide nanoclusters epitaxially embedded in an MgO matrix are studied via electron transport, magneto-resistance, and X-ray circular dichroism measurements. The metal-insulator transition temperature is observed to be in the range of 1.5-27 K. We observe, from 0.3 K to at least 125 K, a superparamagnetic behavior, whereas vanadium oxide, in its bulk phase, is reported to be anti-ferromagnetic (AF) at low temperatures. This striking feature is consistent with either ferromagnetic spin pairing or spin canting in the AF spin order along the 1D vanadium ion chains of the Magn eli phase or for the VO 2 (A)-like phase. Finally, the observed magneto-resistive effect, which reached up to 8% at low temperatures, indicates ferromagnetic behavior for some of the nanoparticles. This enables their integration in spintronic devices that could be combined with metal-insulator switching and magneto-resistive effects.
Published: 2020
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3. High Spin Polarization at Ferromagnetic Metal–Organic Interfaces: A Generic Property

Author: P. Wetzel, Wulf Wulfhekel, Loïc Joly, Amina Taleb-Ibrahimi, Manuel Gruber, Eric Beaurepaire, Dimitra Xenioti, Mebarek Alouani, Jacek Arabski, Fabrice Scheurer, Samar Hajjar-Garreau, Patrick Le Fèvre, Martin Bowen, François Bertran, Wolfgang Weber, Samy Boukari, Fatima Djeghloul, Hervé Bulou, G. Garreau, and E. Urbain
Subjects: Materials science, Spintronics, Spin polarization, Condensed matter physics, Generic property, Photoemission spectroscopy, Fermi level, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Condensed Matter::Materials Science, symbols.namesake, D band, Ferromagnetism, 0103 physical sciences, symbols, Molecule, Condensed Matter::Strongly Correlated Electrons, General Materials Science, Physical and Theoretical Chemistry, 010306 general physics, 0210 nano-technology
Abstract: A high spin polarization of states around the Fermi level, EF, at room temperature has been measured in the past at the interface between a few molecular candidates and the ferromagnetic metal Co. Is this promising property for spintronics limited to these candidates? Previous reports suggested that certain conditions, such as strong ferromagnetism, i.e., a fully occupied spin-up d band of the ferromagnet, or the presence of π bonds on the molecule, i.e., molecular conjugation, needed to be met. What rules govern the presence of this property? We have performed spin-resolved photoemission spectroscopy measurements on a variety of such interfaces. We find that this property is robust against changes to the molecule and ferromagnetic metal's electronic properties, including the aforementioned conditions. This affirms the generality of highly spin-polarized states at the interface between a ferromagnetic metal and a molecule and augurs bright prospects toward integrating these interfaces within organic spintronic devices.
Published: 2016
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4. Electrofluorochromism at the single-molecule level

Author: Michael C. Chong, Guillaume Schull, Fabrice Scheurer, Hervé Bulou, Benjamin Doppagne, Alex Boeglin, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)
Subjects: FOS: Physical sciences, Insulator (electricity), 02 engineering and technology, Electroluminescence, 01 natural sciences, law.invention, Oxidation state, law, Physics - Chemical Physics, 0103 physical sciences, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Molecule, 010306 general physics, Plasmon, ComputingMilieux_MISCELLANEOUS, Chemical Physics (physics.chem-ph), [PHYS]Physics [physics], Multidisciplinary, Condensed Matter - Mesoscale and Nanoscale Physics, 021001 nanoscience & nanotechnology, Fluorescence, 3. Good health, Radical ion, Chemical physics, Scanning tunneling microscope, 0210 nano-technology
Abstract: The interplay between the oxidation state and the optical properties of molecules plays a key role for applications in displays, sensors or molecular-based memories. The fundamental mechanisms occurring at the level of a single-molecule have been difficult to probe. We used a scanning tunneling microscope (STM) to characterize and control the fluorescence of a single Zn-phthalocyanine radical cation adsorbed on a NaCl-covered Au(111) sample. The neutral and oxidized states of the molecule were identified on the basis of their fluorescence spectra that revealed very different emission energies and vibronic fingerprints. The emission of the charged molecule was controlled by tuning the thickness of the insulator and the plasmons localized at the apex of the STM tip. In addition, sub-nanometric variations of the tip position were used to investigate the charging and electroluminescence mechanisms., 11 pages, 4 figures
Published: 2018
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5. Fano Description of Single-Hydrocarbon Fluorescence Excited by a Scanning Tunneling Microscope

Author: Jörg Kröger, Benjamin Doppagne, Fabrice Scheurer, Guillaume Schull, scheurer, fabrice, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), and Technische Universität Ilmenau (TU )
Subjects: Materials science, polyaromatic hydrocarbon, Exciton, FOS: Physical sciences, Bioengineering, 02 engineering and technology, 01 natural sciences, Molecular physics, law.invention, [PHYS.PHYS.PHYS-CHEM-PH] Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], law, 0103 physical sciences, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Fano, Physics::Atomic and Molecular Clusters, General Materials Science, Physics::Chemical Physics, 010306 general physics, STM-induced luminesence, Plasmon, Quantum tunnelling, Condensed Matter - Mesoscale and Nanoscale Physics, Mechanical Engineering, single-molecule fluorescence, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Single-molecule experiment, 3. Good health, Excited state, Light emission, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Scanning tunneling microscope, 0210 nano-technology, Luminescence
Abstract: The detection of fluorescence with submolecular resolution enables the exploration of spatially varying photon yields and vibronic properties at the single-molecule level. By placing individual polycyclic aromatic hydrocarbon molecules into the plasmon cavity formed by the tip of a scanning tunneling microscope and a NaCl-covered Ag(111) surface, molecular light emission spectra are obtained that unravel vibrational progression. In addition, light spectra unveil a signature of the molecule even when the tunneling current is injected well separated from the molecular emitter. This signature exhibits a distance-dependent Fano profile that reflects the subtle interplay between inelastic tunneling electrons, the molecular exciton and localized plasmons in at-distance as well as on-molecule fluorescence. The presented findings open the path to luminescence of a different class of molecules than investigated before and contribute to the understanding of single-molecule luminescence at surfaces in a unified picture., Comment: 24 pages, 4 figures
Published: 2018
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6. Linking Electronic Transport through a Spin Crossover Thin Film to the Molecular Spin State Using X-ray Absorption Spectroscopy Operando Techniques

Author: E. Urbain, Daniel Lacour, Michał Studniarek, Wulf Wulfhekel, Guy Schmerber, Alberto Riminucci, B. Gobaut, Ufuk Halisdemir, L. M. Kandpal, K. Katcko, Fadi Choueikani, Fabrice Scheurer, Martin Bowen, Jinjie Chen, Loïc Joly, Samy Boukari, F. Schleicher, Jacek Arabski, Eric Beaurepaire, Timo Frauhammer, Marie Hervé, Kuppusamy Senthil Kumar, Edwige Otero, Wolfgang Weber, Mario Ruben, Philippe Ohresser, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Institut Jean Lamour (IJL), Université de Lorraine (UL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), and Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique
Subjects: operando measurements, Materials science, Spin states, Absorption spectroscopy, spin crossover thin film, FOS: Physical sciences, 02 engineering and technology, Applied Physics (physics.app-ph), 010402 general chemistry, 01 natural sciences, Spin crossover, Molecular film, Molecule, General Materials Science, Thin film, solid-state device, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], spintronics, [PHYS]Physics [physics], X-ray absorption spectroscopy, Spintronics, Physics - Applied Physics, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Chemical physics, 0210 nano-technology
Abstract: One promising route toward encoding information is to utilize the two stable electronic states of a spin crossover molecule. However, while this property is clearly manifested in transport across single molecule junctions, evidence linking charge transport across a solid-state device to the molecular film's spin state has thus far remained indirect. To establish this link, we deploy materials-centric and device-centric operando experiments involving X-ray absorption spectroscopy. We find a correlation between the temperature dependencies of the junction resistance and the Fe spin state within the device's Fe(bpz)2(phen) molecular film. We also factually observe that the Fe molecular site mediates charge transport. Our dual operando studies reveal that transport involves a subset of molecules within an electronically heterogeneous spin crossover film. Our work confers an insight that substantially improves the state-of-the-art regarding spin crossover-based devices, thanks to a methodology that can benefit device studies of other next-generation molecular compounds., Typo in the first name of one of the authors updated (Jinje -> Jinjie)
Published: 2018
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7. Bright Electroluminescence from Single Graphene Nanoribbon Junctions

Author: Andrea Ferretti, Deborah Prezzi, Claudia Cardoso, Nasima Afsharimani, Fabrice Scheurer, Michael C. Chong, Guillaume Schull, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), and scheurer, fabrice
Subjects: Materials science, Band gap, FOS: Physical sciences, Bioengineering, 02 engineering and technology, Substrate (electronics), Electroluminescence, 010402 general chemistry, 01 natural sciences, law.invention, electroluminescence, law, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), General Materials Science, Emission spectrum, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], density functional theory, GW-BSE, Condensed Matter - Materials Science, Condensed Matter - Mesoscale and Nanoscale Physics, Graphene, business.industry, Mechanical Engineering, Graphene nanoribbons, Materials Science (cond-mat.mtrl-sci), Biasing, General Chemistry, scanning tunneling microscopy induced light emission, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 0104 chemical sciences, 3. Good health, Optoelectronics, single-molecule junction, Scanning tunneling microscope, 0210 nano-technology, business, [PHYS.COND] Physics [physics]/Condensed Matter [cond-mat]
Abstract: Thanks to their highly tunable band gaps, graphene nanoribbons (GNRs) with atomically precise edges are emerging as mechanically and chemically robust candidates for nanoscale light emitting devices of modulable emission color. While their optical properties have been addressed theoretically in depth, only few experimental studies exist, limited to ensemble measurements and without any attempt to integrate them in an electronic-like circuit. Here we report on the electroluminescence of individual GNRs suspended between the tip of a scanning tunneling microscope (STM) and a Au(111) substrate, constituting thus a realistic opto-electronic circuit. Emission spectra of such GNR junctions reveal a bright and narrow band emission of red light, whose energy can be tuned with the bias voltage applied to the junction, but always lying below the gap of infinite GNRs. Comparison with {\it ab initio} calculations indicate that the emission involves electronic states localized at the GNR termini. Our results shed light on unpredicted optical transitions in GNRs and provide a promising route for the realization of bright, robust and controllable graphene-based light emitting devices., Comment: Supporting Information avail on the ACS website at DOI: 10.1021/acs.nanolett.7b03797
Published: 2018
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8. Cu Metal/Mn Phthalocyanine Organic Spinterfaces atop Co with High Spin Polarization at Room Temperature

Author: Samy Boukari, Jacek Arabski, Fatima Ibrahim, P. Le Fèvre, François Bertran, P. Wetzel, Martin Bowen, G. Garreau, Michał Studniarek, Eric Beaurepaire, Loïc Joly, E. Denys, Fabrice Scheurer, E. Urbain, Wolfgang Weber, F. Ngassam Nyakam, Mebarek Alouani, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Institut de Science des Matériaux de Mulhouse (IS2M), Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), and Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique
Subjects: Materials science, FOS: Physical sciences, 02 engineering and technology, 01 natural sciences, [SPI.MAT]Engineering Sciences [physics]/Materials, Biomaterials, Metal, chemistry.chemical_compound, Condensed Matter::Materials Science, Spin crossover, 0103 physical sciences, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Electrochemistry, 010306 general physics, Condensed Matter - Materials Science, Condensed Matter - Mesoscale and Nanoscale Physics, Spin polarization, Materials Science (cond-mat.mtrl-sci), 021001 nanoscience & nanotechnology, Condensed Matter Physics, 3. Good health, Electronic, Optical and Magnetic Materials, chemistry, visual_art, visual_art.visual_art_medium, Phthalocyanine, Physical chemistry, Condensed Matter::Strongly Correlated Electrons, 0210 nano-technology
Abstract: The organic spinterface describes the spin-polarized properties that develop, due to charge transfer, at the interface between a ferromagnetic metal (FM) and the molecules of an organic semiconductor. Yet, if the latter is also magnetic (e.g. molecular spin chains), the interfacial magnetic coupling can generate complexity within magnetotransport experiments. Also, assembling this interface may degrade the properties of its constituents (e.g. spin crossover or non-sublimable molecules). To circumvent these issues, one can separate the molecular and FM films using a less reactive nonmagnetic metal (NM). Spin-resolved photoemission spectroscopy measurements on the prototypical system Co(001)//Cu/Mnphthalocyanine (MnPc) reveal that the Cu/MnPc spinterface atop ferromagnetic Co is highly spin-polarized at room temperature, up to Cu spacer thicknesses of at least 10 monolayers. Ab-initio theory describes a spin polarization of the topmost Cu layer after molecular hybridization that can be accompanied by magnetic hardening effects. This spinterface's unexpected robustness paves the way for 1) integrating electronically fragile molecules within organic spinterfaces, and 2) manipulating molecular spin chains using the well-documented spin transfer torque properties of the FM/NM bilayer., Comment: 16 pages. Submitted
Published: 2018
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9. Modulating the Ferromagnet/Molecule Spin Hybridization Using an Artificial Magnetoelectric

Author: Wolfgang Weber, Olivia Mauguin, Martin Bowen, Victor Da Costa, Michał Studniarek, Salia Cherifi-Hertel, Eric Beaurepaire, Guy Schmerber, Marie Hervé, Fadi Choueikani, Jacek Arabski, Charles-Henri Lambert, Cécile Marcelot, E. Urbain, Samy Boukari, Edwige Otero, Ludovic Largeau, Ufuk Halisdemir, Florian Leduc, Philippe Ohresser, Bénédicte Warot-Fonrose, Rémi Arras, F. Schleicher, Beata Taudul, Fabrice Scheurer, Wulf Wulfhekel, Loïc Joly, Abbass Hamadeh, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Matériaux et dispositifs pour l'Electronique et le Magnétisme (CEMES-MEM), Centre d'élaboration de matériaux et d'études structurales (CEMES), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), Physikalisches Institut [Karlsruhe] (PHI), Karlsruher Institut für Technologie (KIT), Institut Jean Lamour (IJL), Université de Lorraine (UL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Centre de Nanosciences et de Nanotechnologies [Marcoussis] (C2N), Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), and Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)
Subjects: X-ray absorption spectroscopy, Materials science, Condensed matter physics, Spintronics, Spin polarization, [PHYS.PHYS]Physics [physics]/Physics [physics], Magnetic circular dichroism, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Polarization (waves), 01 natural sciences, Ferroelectricity, 0104 chemical sciences, Electronic, Optical and Magnetic Materials, Biomaterials, Condensed Matter::Materials Science, Ferromagnetism, Electrochemistry, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Molecule, Condensed Matter::Strongly Correlated Electrons, [PHYS.COND.CM-SCE]Physics [physics]/Condensed Matter [cond-mat]/Strongly Correlated Electrons [cond-mat.str-el], 0210 nano-technology
Abstract: International audience; Spin-polarized charge transfer at the interface between a ferromagnetic (FM)metal and a molecule can lead to ferromagnetic coupling and to a high spinpolarization at room temperature. The magnetic properties of these interfacescan not only alter those of the ferromagnet but can also stabilize molecularspin chains with interesting opportunities toward quantum computing. Withthe aim to enhance an organic spintronic device’s functionality, external controlover this spin polarization may thus be achieved by altering the ferromagnet/molecule interface’s magnetic properties. To do so, the magnetoelectricproperties of an underlying ferroelectric/ferromagnetic interface are utilized.Switching the ferroelectric polarization state of a PbZr0.2Ti0.8O3 (PZT) bottomlayer within a PZT/Co/FePc-based (Pc - phthalocyanine) device alters the X-raymagnetic circular dichroism of the Fe site within the phthalocyanine moleculartop layer. Thus, how to electrically alter the magnetic properties of an interfacewith high spin polarization at room temperature is demonstrated. Thisexpands electrical control over spin-polarized FM/molecule interfaces, which isfirst demonstrated using ferroelectric molecules, to all molecular classes.
Published: 2017
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10. Vibronic Spectroscopy with Submolecular Resolution from STM-Induced Electroluminescence

Author: Fabrice Scheurer, Hervé Bulou, Alex Boeglin, Stéphane Berciaud, Michelangelo Romeo, Etienne Lorchat, Benjamin Doppagne, Michael C. Chong, Guillaume Schull, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), univOAK, Archive ouverte, Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: [CHIM.MATE] Chemical Sciences/Material chemistry, Materials science, Resolution (electron density), General Physics and Astronomy, 02 engineering and technology, [CHIM.MATE]Chemical Sciences/Material chemistry, Electroluminescence, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 021001 nanoscience & nanotechnology, 01 natural sciences, Fluorescence, 3. Good health, law.invention, law, 0103 physical sciences, Physics::Atomic and Molecular Clusters, Vibronic spectroscopy, Molecule, Scanning tunneling microscope, Atomic physics, Physics::Chemical Physics, 010306 general physics, 0210 nano-technology
Abstract: A scanning tunneling microscope is used to generate the electroluminescence of phthalocyanine molecules deposited on NaCl/Ag(111). Photon spectra reveal an intense emission line at approximate to 1.9 eV that corresponds to the fluorescence of the molecules, and a series of weaker redshifted lines. Based on a comparison with Raman spectra acquired on macroscopic molecular crystals, these spectroscopic features can be associated with the vibrational modes of the molecules and provide a detailed chemical fingerprint of the probed species. Maps of the vibronic features reveal submolecularly resolved structures whose patterns are related to the symmetry of the probed vibrational modes.
Published: 2017
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11. Efficient Spin-Flip Excitation of a Nickelocene Molecule

Author: Benjamin Verlhac, Marie-Laure Bocquet, Loïc Joly, P. N. Abufager, Fabrice Scheurer, Philippe Ohresser, Marisa N. Faraggi, Laurent Limot, M. Ormaza, Nicolás Lorente, Michelangelo Romeo, N. Bachellier, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), scheurer, fabrice, Processus d'Activation Sélective par Transfert d'Energie Uni-électronique ou Radiatif (UMR 8640) (PASTEUR), Département de Chimie - ENS Paris, École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Universidad Nacional de Rosario [Argentina], CEA- Saclay (CEA), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Centro de Fisica de Materiales (CFM), Universidad del Pais Vasco / Euskal Herriko Unibertsitatea [Espagne] (UPV/EHU)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Donostia International Physics Center - DIPC (SPAIN), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU)-University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), limot, laurent, and Agence Nationale de la Recherche (France)
Subjects: inelastic electron tunneling spectroscopy, Magnetism, Ciencias Físicas, Bioengineering, 02 engineering and technology, 01 natural sciences, law.invention, [PHYS] Physics [physics], law, 0103 physical sciences, Atom, General Materials Science, 010306 general physics, Tip functionalization, Magnetic anisotropy, tip functionalization, density functional theory, Metallocene, [PHYS]Physics [physics], magnetic anisotropy, Magnetic moment, Inelastic electron tunneling spectroscopy, Chemistry, Magnetic circular dichroism, Mechanical Engineering, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, spin-flip, Density functional theory, X-ray magnetic circular dichroism, Atomic physics, Scanning tunneling microscope, Spin-flip, 0210 nano-technology, Excitation, CIENCIAS NATURALES Y EXACTAS, Física de los Materiales Condensados
Abstract: Inelastic electron tunneling spectroscopy (IETS) within the junction of a scanning tunneling microscope (STM) uses current-driven spin-flip excitations for an all-electrical characterization of the spin state of a single object. Usually decoupling layers between the single object, atom or molecule, and the supporting surface are needed to observe these excitations. Here we study the surface magnetism of a sandwich nickelocene molecule (Nc) adsorbed directly on Cu(100) by means of X-ray magnetic circular dichroism (XMCD) and density functional theory (DFT) calculations and show with IETS that it exhibits an exceptionally efficient spin-flip excitation. The molecule preserves its magnetic moment and magnetic anisotropy not only on Cu(100), but also in different metallic environments including the tip apex. By taking advantage of this robusteness, we are able to functionalize the microscope tip with a Nc, which can be employed as a portable source of inelastic excitations as exemplified by a double spin-flip excitation process., This work has been supported by the Agence Nationale de la Recherche (Grant Nos. ANR-13-BS10–0016, ANR-11-LABX-0058 NIE, ANR-10-LABX-0026 CSC).
Published: 2017
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12. Ordinary and Hot Electroluminescence from Single-Molecule Devices: Controlling the Emission Color by Chemical Engineering

Author: Lydia Sosa-Vargas, Hervé Bulou, Michael C. Chong, Fabrice Mathevet, Guillaume Schull, Alex Boeglin, Fabrice Scheurer, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Institut Parisien de Chimie Moléculaire (IPCM), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Chimie des polymères (LCP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut Parisien de Chimie Moléculaire (IPCM), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)
Subjects: Microscope, Bioengineering, Astrophysics::Cosmology and Extragalactic Astrophysics, 02 engineering and technology, Electroluminescence, 01 natural sciences, law.invention, law, 0103 physical sciences, Molecule, [CHIM]Chemical Sciences, General Materials Science, Emission spectrum, 010306 general physics, Astrophysics::Galaxy Astrophysics, Quantum tunnelling, ComputingMilieux_MISCELLANEOUS, Chemistry, business.industry, Mechanical Engineering, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 3. Good health, Excited state, Optoelectronics, Scanning tunneling microscope, 0210 nano-technology, Luminescence, business
Abstract: Single-molecule junctions specifically designed for their optical properties are operated as light-emitting devices using a cryogenic scanning tunneling microscope. They are composed of an emitting unit—a molecular chromophore—suspended between a Au(111) surface and the tip of the microscope by organic linkers. Tunneling electrons flowing through these junctions generate a narrow-line emission of light whose color is controlled by carefully selecting the chemical structure of the emitting unit. Besides the main emission line, red and blue-shifted vibronic features of low intensity are also detected. While the red-shifted features provide a spectroscopic fingerprint of the emitting unit, the blue-shifted ones are interpreted in terms of hot luminescence from vibrationally excited states of the molecule.
Published: 2016
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13. Simple and advanced ferromagnet/molecule spinterfaces

Author: F. Djedhloul, Fatima Ibrahim, Hashim Jabbar, Philippe Ohresser, Fabrice Scheurer, Kai Chen, Edwige Otero, Jacek Arabski, Clément Barraud, P. Le Fèvre, Richard Mattana, Samar Hajjar-Garreau, Wulf Wulfhekel, Samy Boukari, Ufuk Halisdemir, François Bertran, E. Urbain, Hironari Isshiki, Frédéric Petroff, Moritz Peter, Martin Bowen, Mebarek Alouani, Pierre Seneor, A. Taleb-Ibrahimi, P. Wetzel, Loïc Joly, Cyrile Deranlot, Michał Studniarek, Eric Beaurepaire, V. Da Costa, Fadi Choueikani, Stéphane Fusil, D. Xenioti, Hervé Bulou, G. Garreau, Jinjie Chen, Karim Bouzehouane, V. Davesne, Wolfgang Weber, and Manuel Gruber
Subjects: Materials science, Condensed matter physics, Spin polarization, Fermi level, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Organic semiconductor, Condensed Matter::Materials Science, symbols.namesake, Exchange bias, Ferromagnetism, Spin crossover, 0103 physical sciences, symbols, Antiferromagnetism, Condensed Matter::Strongly Correlated Electrons, 010306 general physics, 0210 nano-technology, Quantum tunnelling
Abstract: Spin-polarized charge transfer between a ferromagnet and a molecule can promote molecular ferromagnetism 1, 2 and hybridized interfacial states3, 4. Observations of high spin-polarization of Fermi level states at room temperature5 designate such interfaces as a very promising candidate toward achieving a highly spin-polarized, nanoscale current source at room temperature, when compared to other solutions such as half-metallic systems and solid-state tunnelling over the past decades. We will discuss three aspects of this research. 1) Does the ferromagnet/molecule interface, also called an organic spinterface, exhibit this high spin-polarization as a generic feature? Spin-polarized photoemission experiments reveal that a high spin-polarization of electronics states at the Fermi level also exist at the simple interface between ferromagnetic cobalt and amorphous carbon6. Furthermore, this effect is general to an array of ferromagnetic and molecular candidates7. 2) Integrating molecules with intrinsic properties (e.g. spin crossover molecules) into a spinterface toward enhanced functionality requires lowering the charge transfer onto the molecule8 while magnetizing it1,2. We propose to achieve this by utilizing interlayer exchange coupling within a more advanced organic spinterface architecture. We present results at room temperature across the fcc Co(001)/Cu/manganese phthalocyanine (MnPc) system9. 3) Finally, we discuss how the Co/MnPc spinterface’s ferromagnetism stabilizes antiferromagnetic ordering at room temperature onto subsequent molecules away from the spinterface, which in turn can exchange bias the Co layer at low temperature10. Consequences include tunnelling anisotropic magnetoresistance across a CoPc tunnel barrier11. This augurs new possibilities to transmit spin information across organic semiconductors using spin flip excitations12.
Published: 2016
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14. Interface Magnetoelectric Coupling in Co/Pb(Zr,Ti)O3

Author: Gervasi Herranz, Matthieu Jamet, Salia Cherifi-Hertel, Riccardo Hertel, Philippe Ohresser, Bénédicte Warot-Fonrose, Rémi Arras, L. Calmels, Cécile Marcelot, Romain Jarrier, Fabrice Scheurer, Ondřej Vlašín, Agence Nationale de la Recherche (France), Ministerio de Economía y Competitividad (España), Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Matériaux et dispositifs pour l'Electronique et le Magnétisme (CEMES-MEM), Centre d'élaboration de matériaux et d'études structurales (CEMES), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie de Toulouse (ICT-FR 2599), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Chimie du CNRS (INC)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut de Chimie du CNRS (INC)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA), Interférométrie, In situ et Instrumentation pour la Microscopie Electronique (CEMES-I3EM), 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), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Unité mixte de physique CNRS/Thales (UMPhy CNRS/THALES), Centre National de la Recherche Scientifique (CNRS)-THALES, ANR-11-JS10-0009,DYNAMECS,Processus dynamiques dans des matériaux magnétoélectriques(2011), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut National des Sciences Appliquées (INSA)-Université de Toulouse (UT)-Institut de Chimie de Toulouse (ICT), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique (Toulouse) (Toulouse INP), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), THALES [France]-Centre National de la Recherche Scientifique (CNRS), and THALES-Centre National de la Recherche Scientifique (CNRS)
Subjects: [PHYS]Physics [physics], Materials science, Magnetic structure, Condensed matter physics, Magnetic circular dichroism, Electro-optic effect, Magnetoelectric effect, 02 engineering and technology, 021001 nanoscience & nanotechnology, Interface-mediated coupling, 01 natural sciences, Magnetization, Nuclear magnetic resonance, Artificial multiferroics, Transmission electron microscopy, Electric field, 0103 physical sciences, Magneto-optic effect, Magnetoelectrics, General Materials Science, Multiferroics, Density functional theory, [PHYS.COND]Physics [physics]/Condensed Matter [cond-mat], 010306 general physics, 0210 nano-technology
Abstract: Vlašín, Ondřej et al., Magnetoelectric coupling at multiferroic interfaces is a promising route toward the nonvolatile electric-field control of magnetization. Here, we use optical measurements to study the static and dynamic variations of the interface magnetization induced by an electric field in Co/ PbZr0.2Ti0.8O3 (Co/PZT) bilayers at room temperature. The measurements allow us to identify different coupling mechanisms. We further investigate the local electronic and magnetic structure of the interface by means of transmission electron microscopy, soft X-ray magnetic circular dichroism, and density functional theory to corroborate the coupling mechanism. The measurements demonstrate a mixed linear and quadratic optical response to the electric field, which results from a magneto-electto-optical effect. We propose a decomposition method of the optical signal to discriminate between different components involved in the electric field-induced polarization rotation of the reflected light. This allows us to extract a signal that we can ascribe to interface magnetoelectric coupling. The associated surface magnetization exhibits a clear hysteretic variation of odd symmetry with respect to the electric field and nonzero remanence. The interface coupling is remarkably stable over a wide frequency range (1-50 kHz), and the application of a bias magnetic field is not necessary for the coupling to occur. These results show the potential of exploiting interface coupling with the prospect of optimizing the performance of magnetoelectric memory devices in terms of stability, as well as fast and dissipationless operation., This work is supported by the French National Research Agency (ANR) through JCJC program "DYNAMECS” ANR-11-JS10-009-01 and the TEM study was conducted in the framework of project "EMMA” ANR-12-BS10-013. Financial support by the Spanish Government for the CSIC JAE-predoc grant of O.V. is acknowledged. S. C.-H. acknowledges the technical assistance of J.-S. Pelle (IPHC, Strasbourg) and the team of the STnano cleanroom facility in Strasbourg for the optimization of the magnetoelectric micro-devices. R. Cours (CEMES, Toulouse) is acknowledged for his help with the preparation of the sample lamellas for TEM measurements.
Published: 2016
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15. Single molecules as whispering galleries for electrons

Author: Gaël Reecht, Hervé Bulou, Guillaume Schull, and Fabrice Scheurer
Subjects: Physics, business.industry, Physics::Optics, Elementary particle, 02 engineering and technology, Electron, Fermion, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Whispering, 01 natural sciences, Computational physics, Optics, 0103 physical sciences, Molecule, General Materials Science, Whispering-gallery wave, 010306 general physics, 0210 nano-technology, business, Sound wave, Lepton
Abstract: Whispering gallery modes, well-known for acoustic and optical waves, have been shown recently for electrons in molecules on surfaces. The existence of such waves opens new possibilities for nanoelectronic devices. Here we propose a simple analytical textbook model which allows the main characteristic features of such electronic waves to be understood. The model is illustrated by two- and three-dimensional experimental situations.
Published: 2016

16. Low-Temperature Surface Diffusion on Metallic Surfaces

Author: Stefan Stanescu, Fabrice Scheurer, Philippe Ohresser, Emilie Gaudry, Christine Boeglin, Hervé Bulou, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Institut Jean Lamour (IJL), Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), and Université de Lorraine (UL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Surface diffusion, Condensed matter physics, Magnetic circular dichroism, Chemistry, Diffusion, Monte Carlo method, Time evolution, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, Metal, Condensed Matter::Materials Science, General Energy, visual_art, 0103 physical sciences, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], visual_art.visual_art_medium, Physical and Theoretical Chemistry, 010306 general physics, 0210 nano-technology, Quantum tunnelling, Line (formation)
Abstract: International audience; We present a study of the atomic surface diffusion at low temperature of Cr adatoms deposited on Cu(100), Cu(111), and Au(111) surfaces. Time-dependent X-ray magnetic circular dichroism (XMCD), Monte Carlo simulations, and the Kimball−Shortley iterative method are used to evidence a mechanism of quantum tunneling involved in the Cr adatom surface diffusion at temperatures below 40 K. We show that the XMCD line shape is correlated to the atomic configuration of Cr deposited on a metallic surface. A diffusion rate ranging from 0.03 Hz for Cu(100) to 30 Hz for Au(111) at 10 K is reported from the time evolution of the XMCD line shape. A quantum equation of motion for the Cr adatom is derived and solved by using a Kimball−Shortley iterative method. Good agreement between the calculated Bohr periods and the experimental diffusion rates is reported.
Published: 2009
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17. Narrow-line single-molecule transducer between electronic circuits and surface plasmons

Author: Hervé Bulou, Alex Boeglin, Gaël Reecht, Guillaume Schull, Fabrice Scheurer, Michael C. Chong, Fabrice Mathevet, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Chimie des polymères (LCP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut Parisien de Chimie Moléculaire (IPCM), Institut de Chimie du CNRS (INC)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), and Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Materials science, Exciton, Aucun, General Physics and Astronomy, FOS: Physical sciences, Nanotechnology, 02 engineering and technology, 01 natural sciences, law.invention, Laser linewidth, Molecular wire, law, 0103 physical sciences, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), [CHIM]Chemical Sciences, 010306 general physics, ComputingMilieux_MISCELLANEOUS, Plasmon, Condensed Matter - Mesoscale and Nanoscale Physics, business.industry, Surface plasmon, 021001 nanoscience & nanotechnology, Transducer, Optoelectronics, Scanning tunneling microscope, 0210 nano-technology, business, Excitation
Abstract: A molecular wire containing an emitting molecular center is controllably suspended between the plasmonic electrodes of a cryogenic scanning tunneling microscope. Passing current through this circuit generates an ultranarrow-line emission at an energy of approximate to 1.5 eV which is assigned to the fluorescence of the molecular center. Control over the linewidth is obtained by progressively detaching the emitting unit from the surface. The recorded spectra also reveal several vibronic peaks of low intensities that can be viewed as a fingerprint of the emitter. Surface plasmons localized at the tip-sample interface are shown to play a major role in both excitation and emission of the molecular excitons.
Published: 2015
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18. Probing a Device's Active Atoms

Author: E. Urbain, Charles-Henri Lambert, Martin Bowen, Olivia Zill, Michel Hehn, Daniel Lacour, Anant Dixit, Samy Boukari, Loïc Joly, Sébastien Petit-Watelot, Pierre André Guitard, Michał Studniarek, Abbass Hamadeh, Marie Hervé, Jacek Arabski, Eric Beaurepaire, Philippe Ohresser, Wulf Wulfhekel, Wolfgang Weber, Fadi Choueikani, F. Schleicher, Guy Schmerber, Elmer Monteblanco, Fabrice Scheurer, Edwige Otero, Beata Taudul, François Montaigne, Mebarek Alouani, Manuel Acosta, Ufuk Halisdemir, Victor Da Costa, Florian Leduc, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Institut Jean Lamour (IJL), Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Service de physique de l'état condensé (SPEC - UMR3680), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Facultad de CC Economicas y Empresariales, Universidad de Cádiz (UCA), Dispositifs et Instrumentation en Optoélectronique et micro-ondes (DIOM), Université Jean Monnet [Saint-Étienne] (UJM), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Max-Planck-Institut für Mikrostrukturphysik (MPI-HALLE), Max-Planck-Gesellschaft, Department of Information, Documentation and Communication, State Institute for Schools, Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Université Jean Monnet - Saint-Étienne (UJM), and Université de Lorraine (UL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Photon, Materials science, Absorption spectroscopy, Spintronics, business.industry, Mechanical Engineering, Heterojunction, 02 engineering and technology, Photon energy, 021001 nanoscience & nanotechnology, 01 natural sciences, 7. Clean energy, Tunnel magnetoresistance, Optics, Mechanics of Materials, [PHYS.COND.CM-GEN]Physics [physics]/Condensed Matter [cond-mat]/Other [cond-mat.other], 0103 physical sciences, Optoelectronics, Microelectronics, General Materials Science, 010306 general physics, 0210 nano-technology, business, Absorption (electromagnetic radiation)
Abstract: International audience; Devices studies are often augmented by separately conducted materials science studies to achieve better insight into device operation [1–4]. In one such materials science technique called X-ray absorption spectroscopy (XAS), the energy of soft X-ray photons is tuned so as to drive core level excitations of a specific atomic species within the sample (see Figure 1a). The resulting absorption spectrum yields information on the quantity and charge state of these atoms present, on their chemical environment and their resulting electronic/magnetic properties. When applied using the brilliance of a synchrotron facility, this technique is sensitive to minute populations of atoms, even when buried within a heterostructure. Resolving the properties of these atoms within a device built from this heterostruc-ture is in turn interpreted as providing insight into the device's performance. [2,5] As an important refinement, operando studies [6–12] alter the device's state (e.g., Materials science and device studies have, when implemented jointly as " operando " studies, better revealed the causal link between the properties of the device's materials and its operation, with applications ranging from gas sensing to information and energy technologies. Here, as a further step that maximizes this causal link, the paper focuses on the electronic properties of those atoms that drive a device's operation by using it to read out the materials property. It is demonstrated how this method can reveal insight into the operation of a macroscale, industrial-grade microelectronic device on the atomic level. A magnetic tunnel junction's (MTJ's) current, which involves charge transport across different atomic species and interfaces, is measured while these atoms absorb soft X-rays with synchrotron-grade brilliance. X-ray absorption is found to affect magnetotransport when the photon energy and linear polarization are tuned to excite FeO bonds parallel to the MTJ's interfaces. This explicit link between the device's spintronic performance and these FeO bonds, although predicted, challenges conventional wisdom on their detrimental spintronic impact. The technique opens interdisciplinary possibilities to directly probe the role of different atomic species on device operation, and shall considerably simplify the materials science iterations within device research.
Published: 2017
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19. Electroluminescence of a Polythiophene Molecular Wire Suspended between a Metallic Surface and the Tip of a Scanning Tunneling Microscope

Author: Virginie Speisser, Gaël Reecht, Fabrice Scheurer, Yannick J. Dappe, Guillaume Schull, and Fabrice Mathevet
Subjects: Materials science, Polarity (physics), business.industry, Astrophysics::High Energy Astrophysical Phenomena, General Physics and Astronomy, 02 engineering and technology, Electroluminescence, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, 021001 nanoscience & nanotechnology, 01 natural sciences, Fluorescence, law.invention, Molecular wire, chemistry.chemical_compound, chemistry, law, 0103 physical sciences, OLED, Optoelectronics, Polythiophene, Scanning tunneling microscope, 010306 general physics, 0210 nano-technology, business, Plasmon
Abstract: The electroluminescence of a polythiophene wire suspended between a metallic surface and the tip of a scanning tunneling microscope is reported. Under positive sample voltage, the spectral and voltage dependencies of the emitted light are consistent with the fluorescence of the wire junction mediated by localized plasmons. This emission is strongly attenuated for the opposite polarity. Both emission mechanism and polarity dependence are similar to what occurs in organic light emitting diodes (OLED) but at the level of a single molecular wire.
Published: 2014
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20. Direct observation of a highly spin-polarized organic spinterface at room temperature

Author: Riccardo Bertacco, Amina Taleb-Ibrahimi, Samy Boukari, Christian Rinaldi, Wolfgang Weber, S. Javaid, P. Le Fèvre, Eric Beaurepaire, Fatima Ibrahim, Richard Mattana, François Bertran, Mebarek Alouani, Philippe Ohresser, J. Arabski, Pierre Seneor, N. B. Brookes, Loïc Joly, F. Djeghloul, T. Miyamachi, J. P. Kappler, Pardeep K. Thakur, Martin Bowen, A. Jaafar, Fabrice Scheurer, Wulf Wulfhekel, Matteo Cantoni, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Politecn Milan, LNESS Dipartimento Fis, I-22100 Como, Italy, Paul Scherrer Inst, CH-5232 Villigen, Switzerland, Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), European Synchrotron Radiation Facility (ESRF), Karlsruhe Inst Technol, Ctr Funct Nanostruct, D-76131 Karlsruhe, Germany, Karlsruhe Inst Technol, Inst Phys, D-76131 Karlsruhe, Germany, Unité mixte de physique CNRS/Thales (UMPhy CNRS/THALES), Centre National de la Recherche Scientifique (CNRS)-THALES, Université Paris-Sud - Paris 11 (UP11), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), and Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique
Subjects: Aucun, Electron, 02 engineering and technology, 7. Clean energy, 01 natural sciences, chemistry.chemical_compound, Organic spintronics, Electronic circuit, Spin-½, [PHYS]Physics [physics], Spin-polarized photoemission spectroscopy, Condensed Matter - Materials Science, Multidisciplinary, Condensed matter physics, Spin polarization, Magnetic moment, Applied Mathematics, Physics, Spin-polarized interface states, Computer Science Applications1707 Computer Vision and Pattern Recognition, Electrical and Electronic Engineering, Electronic, Optical and Magnetic Materials, Condensed Matter Physics, Current source, 021001 nanoscience & nanotechnology, Thermal conduction, Chemical physics, Condensed Matter::Strongly Correlated Electrons, 0210 nano-technology, Materials science, FOS: Physical sciences, Article, Condensed Matter::Materials Science, Atomic orbital, 0103 physical sciences, Electronic, Molecule, ddc:530, Optical and Magnetic Materials, Spin (physics), 010306 general physics, Spintronics, business.industry, Materials Science (cond-mat.mtrl-sci), Organic semiconductor, Semiconductor, Ferromagnetism, chemistry, Phthalocyanine, business
Abstract: International audience; Organic semiconductors constitute promising candidates toward large-scale electronic circuits that are entirely spintronics-driven. Toward this goal, tunneling magnetoresistance values above 300% at low temperature suggested the presence of highly spin-polarized device interfaces. However, such spinterfaces have not been observed directly, let alone at room temperature. Thanks to experiments and theory on the model spinterface between phthalocyanine molecules and a Co single crystal surface, we clearly evidence a highly efficient spinterface. Spin-polarised direct and inverse photoemission experiments reveal a high degree of spin polarisation at room temperature at this interface. We measured a magnetic moment on the molecule's nitrogen p orbitals, which substantiates an ab-initio theoretical description of highly spin-polarised charge conduction across the interface due to differing spinterface formation mechanisms in each spin channel. We propose, through this example, a recipe to engineer simple organic-inorganic interfaces with remarkable spintronic properties that can endure well above room temperature
Published: 2013
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21. Thermodynamics versus kinetics in a morphology transition of nanoparticles

Author: N. Moreau, Hervé Bulou, Christine Goyhenex, Virginie Speisser, Philippe Ohresser, Jérôme Lagoute, Fabrice Scheurer, Michelangelo Romeo, S. Rousset, Yann Girard, C. Chacon, B. Carrière, V. Repain, Edwige Otero, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Laboratoire Matériaux et Phénomènes Quantiques (MPQ (UMR_7162)), Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Département Mécanismes d'Accidents (INRETS/MA), Institut National de Recherche sur les Transports et leur Sécurité (INRETS), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Knoop, Martina, École normale supérieure - Paris (ENS Paris), École normale supérieure - Paris (ENS Paris)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, and PSL Research University (PSL)-PSL Research University (PSL)-Université de Cergy Pontoise (UCP)
Subjects: [PHYS]Physics [physics], Materials science, Thermodynamic equilibrium, Bilayer, chemistry.chemical_element, Thermodynamics, 02 engineering and technology, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Electronic, Optical and Magnetic Materials, [PHYS] Physics [physics], Condensed Matter::Materials Science, chemistry, Picosecond, 0103 physical sciences, Atom, Monolayer, Physics::Atomic and Molecular Clusters, Stress relaxation, Cluster (physics), 010306 general physics, 0210 nano-technology, Palladium
Abstract: The morphology of cobalt, palladium, and platinum nanoclusters grown on a gold surface is analyzed from both thermodynamic and kinetic viewpoints. Although the thermodynamic equilibrium shape as a function of cluster size is similar for all three elements and shows a morphology transition from monolayer to bilayer, only Co clusters meet their stable state and undergo a transition. Atomistic simulations on a picosecond to nanosecond time scale evidence kinetic limitations for Pt and Pd, and allow us to understand the experimentally observed morphology for the different species. It is shown that stress relaxation, by strongly influencing the energy activation for atom hopping from first to second cluster layer and the magnitude of vibration of the atoms, is the determinant parameter for the existence or absence of the cluster morphology transition. DOI: 10.1103/PhysRevB.87.155404
Published: 2013

22. Spin magnetic moments from single atoms to small Cr clusters

Author: R. Decker, Christine Boeglin, Philippe Ohresser, Bence Lazarovits, Hervé Bulou, Fabrice Scheurer, Sarnjeet S. Dhesi, Emilie Gaudry, Idrissou Chado, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), European Synchrotron Radiation Facility (ESRF), Institut Jean Lamour (IJL), Université de Lorraine (UL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Center for Computational Materials Science, Vienna University of Technology (TU Wien), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Technische Universität Wien (TU Wien), Laboratoire de Chimie de la Matière Condensée de Paris (LCMCP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Collège de France (CdF (institution))-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Institut de Chimie du CNRS (INC)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Low-energy electron diffraction, Magnetic moment, Magnetic circular dichroism, Chemistry, 02 engineering and technology, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Molecular physics, Electronic, Optical and Magnetic Materials, law.invention, Paramagnetism, Low-energy electron microscopy, Crystallography, Ferromagnetism, law, 0103 physical sciences, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Antiferromagnetism, Scanning tunneling microscope, 010306 general physics, 0210 nano-technology
Abstract: International audience; Morphology studies at the first stages of the growth of Cr/Au(111) are reported and compared to the magnetic properties of the nanostructures. We analyze by Scanning Tunneling Microscopy and Low Energy Electron Diffraction the Cr clusters growth between 200 K and 300 K. In the early stages of the growth the morphology of the clusters shows monoatomic high islands located at the kinks of the herringbone reconstructed Au(111) surface. By X-ray Magnetic Circular Dichroism performed on the Cr L2,3 edges it is shown that the temperature dependent morphology strongly influences the magnetic properties of the Cr clusters. We show that in the sub-monolayer regime Cr clusters are antiferromagnetic and paramagnetic when the size reaches the atomic limit.
Published: 2005
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23. Real-Time Monitoring of Growing Nanoparticles

Author: Yves Borensztein, O. Ulrich, Fabrice Scheurer, M. Noblet, Jeannot Mane-Mane, Antoine Barbier, Rémi Lazzari, Jacques Jupille, Gilles Renaud, Claude Henry, Frédéric Leroy, J.P. Deville, Olivier Fruchart, C. Revenant, Oxydes en basses dimensions (INSP-E9), Institut des Nanosciences de Paris (INSP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Institut Nanosciences et Cryogénie (INAC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Service de Physique et de Chimie des Surfaces et Interfaces (SPCSI), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Service de Physique des Matériaux et Microstructures (SP2M - UMR 9002), 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]), Centre Interdisciplinaire de Nanoscience de Marseille (CINaM), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Physico-chimie et dynamique des surfaces (INSP-E6), Service de Cytogénétique et de Biologie Cellulaire, Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Hôpital Pontchaillou-CHU Pontchaillou [Rennes], Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Laboratoire Louis Néel (LLN), Centre National de la Recherche Scientifique (CNRS), 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), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes (UR)-Hôpital Pontchaillou-CHU Pontchaillou [Rennes], Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Multidisciplinary, business.industry, Scattering, Nanoparticle, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, 01 natural sciences, 0104 chemical sciences, [SPI.ELEC]Engineering Sciences [physics]/Electromagnetism, Optics, Macroscopic scale, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [SPI.OPTI]Engineering Sciences [physics]/Optics / Photonic, Optoelectronics, Particle, Process control, Sensitivity (control systems), Particle size, [PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph], Small-angle scattering, 0210 nano-technology, business, ComputingMilieux_MISCELLANEOUS
Abstract: One challenge in the production of nanometer-sized objects with given properties is to control their growth at a macroscopic scale in situ and in real time. A dedicated ultrahigh-vacuum grazing-incidence small-angle x-ray scattering setup has been developed, yielding high sensitivity and dynamics. Its capabilities to derive the average particle shape and size and the film growth mode and ordering and to probe both surfaces and buried interfaces are illustrated for two prototypical cases: the model catalyst Pd/MgO(100) and the self-organized Co/Au(111) system. A wide range of technologically important systems can potentially be investigated in various gaseous environments.
Published: 2003
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24. Single-molecule tautomerization tracking through space- and time-resolved fluorescence spectroscopy

Author: Tomáš Neuman, Guillaume Schull, Michelangelo Romeo, Luis E. Parra López, Ruben Soria-Martinez, Benjamin Doppagne, Stéphane Berciaud, Javier Aizpurua, Fabrice Scheurer, Hervé Bulou, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Donostia International Physics Center (DIPC), University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU), schull, guillaume, European Research Council, European Commission, Agence Nationale de la Recherche (France), Université de Strasbourg, Ministerio de Economía y Competitividad (España), Eusko Jaurlaritza, Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, and Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)
Subjects: Molecular switch, [PHYS]Physics [physics], Materials science, Biomedical Engineering, Molecular electronics, Bioengineering, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, Condensed Matter Physics, Single-molecule experiment, 01 natural sciences, Tautomer, Atomic and Molecular Physics, and Optics, Fluorescence spectroscopy, Spectral line, 0104 chemical sciences, [PHYS] Physics [physics], Chemical physics, Excited state, Molecule, General Materials Science, Electrical and Electronic Engineering, 0210 nano-technology
Abstract: Tautomerization, the interconversion between two constitutional molecular isomers, is ubiquitous in nature, plays a major role in chemistry and is perceived as an ideal switch function for emerging molecular-scale devices. Within free-base porphyrin, porphycene or phthalocyanine, this process involves the concerted or sequential hopping of the two inner hydrogen atoms between equivalent nitrogen sites of the molecular cavity. Electronic and vibronic changes that result from this NH tautomerization, as well as details of the switching mechanism, were extensively studied with optical spectroscopies, even with single-molecule sensitivity. The influence of atomic-scale variations of the molecular environment and submolecular spatial resolution of the tautomerization could only be investigated using scanning probe microscopes, at the expense of detailed information provided by optical spectroscopies. Here, we combine these two approaches, scanning tunnelling microscopy (STM) and fluorescence spectroscopy, to study the tautomerization within individual free-base phthalocyanine (HPc) molecules deposited on a NaCl-covered Ag(111) single-crystal surface. STM-induced fluorescence (STM-F) spectra exhibit duplicate features that we assign to the emission of the two molecular tautomers. We support this interpretation by comparing hyper-resolved fluorescence maps(HRFMs) of the different spectral contributions with simulations that account for the interaction between molecular excitons and picocavity plasmons. We identify the orientation of the molecular optical dipoles, determine the vibronic fingerprint of the tautomers and probe the influence of minute changes in their atomic-scale environment. Time-correlated fluorescence measurements allow us to monitor the tautomerization events and to associate the proton dynamics to a switching two-level system. Finally, optical spectra acquired with the tip located at a nanometre-scale distance from the molecule show that the tautomerization reaction occurs even when the tunnelling current does not pass through the molecule. Together with other observations, this remote excitation indicates that the excited state of the molecule is involved in the tautomerization reaction path., The authors thank V. Speisser for technical support and A. Boeglin and Andrei Borissov for fruitful discussions. This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (grant agreement no. 771850). The Agence National de la Recherche (project SMALL’LED no. ANR-14-CE26-0016-01), the Labex NIE (Contract no. ANR-11- LABX-0058_NIE) and the International Center for Frontier Research in Chemistry (FRC) are acknowledged for financial support. R.S.-M. and H.B. acknowledge GENCICINES (Project no. A0060907459) and the Pôle HPC and Equipex Equip@Meso at the University of Strasbourg. T.N. and J.A. acknowledge the project FIS2016-80174-P from the Spanish Ministry of Science, and project ELKARTEK KK-2018/00001 from the Basque Government, as well as grant IT1164-19 from the Basque Government for consolidated groups at the university
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25. Energy funnelling within multichromophore architectures monitored with subnanometre resolution

Author: Michel Féron, Benjamin Doppagne, Fabrice Scheurer, Hervé Bulou, Anna Rosławska, Guillaume Schull, Shuiyan Cao, Michelangelo Romeo, Frédéric Chérioux, Nanjing University of Aeronautics and Astronautics (Nanjing University of Aeronautics and Astronautics), Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et Nanosciences Grand-Est (MNGE), Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS), Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174) (FEMTO-ST), Université de Technologie de Belfort-Montbeliard (UTBM)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Femto-st, MN2S, Université de Strasbourg (UNISTRA)-Matériaux et nanosciences d'Alsace (FMNGE), Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique, Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Centre National de la Recherche Scientifique (CNRS)-Université de Strasbourg (UNISTRA), Université de Technologie de Belfort-Montbeliard (UTBM)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Matériaux et nanosciences d'Alsace (FMNGE), and Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Université de Strasbourg (UNISTRA)-Université de Haute-Alsace (UHA) Mulhouse - Colmar (Université de Haute-Alsace (UHA))-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Réseau nanophotonique et optique
Subjects: Resonant inductive coupling, Light, General Chemical Engineering, [SPI.NANO] Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, FOS: Physical sciences, Trimer, [SPI.MAT] Engineering Sciences [physics]/Materials, Isoindoles, 010402 general chemistry, 01 natural sciences, Fluorescence, [SPI.MAT]Engineering Sciences [physics]/Materials, Biomimetics, Microscopy, Scanning Tunneling, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Organometallic Compounds, Molecule, [SPI.NANO]Engineering Sciences [physics]/Micro and nanotechnologies/Microelectronics, Quantum tunnelling, ComputingMilieux_MISCELLANEOUS, Fluorescent Dyes, Physics, [PHYS]Physics [physics], [SPI.ACOU]Engineering Sciences [physics]/Acoustics [physics.class-ph], [SPI.ACOU] Engineering Sciences [physics]/Acoustics [physics.class-ph], Condensed Matter - Mesoscale and Nanoscale Physics, 010405 organic chemistry, General Chemistry, Chromophore, Acceptor, 0104 chemical sciences, Energy Transfer, Chemical physics, Zinc Compounds, Luminescence, Energy (signal processing)
Abstract: In natural and artificial light-harvesting complexes (LHC) the resonant energy transfer (RET) between chromophores enables an efficient and directional transport of solar energy between collection and reaction centers. The detailed mechanisms involved in this energy funneling are intensely debated, essentially because they rely on a succession of individual RET steps that can hardly be addressed separately. Here, we developed a scanning tunnelling microscopy-induced luminescence (STML) approach allowing visualizing, addressing and manipulating energy funneling within multi-chromophoric structures with sub-molecular precision. We first rationalize the efficiency of the RET process at the level of chromophore dimers. We then use highly resolved fluorescence microscopy (HRFM) maps to follow energy transfer paths along an artificial trimer of descending excitonic energies which reveals a cascaded RET from high- to low-energy gap molecules. Mimicking strategies developed by photosynthetic systems, this experiment demonstrates that intermediate gap molecules can be used as efficient ancillary units to convey energy between distant donor and acceptor chromophores. Eventually, we demonstrate that the RET between donors and acceptors is enhanced by the insertion of passive molecules acting as non-covalent RET bridges. This mechanism, that occurs in experiments performed in inhomogeneous media and which plays a decisive role in fastening RET in photosynthetic systems, is reported at the level of individual chromophores with atomic-scale resolution. As it relies on organic chromophores as elementary components, our approach constitutes a powerful model to address fundamental physical processes at play in natural LHC.
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26. Kondo screening of the spin and orbital magnetic moments of Fe impurities in Cu

Author: Christine Goyhenex, Fabrice Scheurer, J. P. Kappler, Loïc Joly, Pietro Gambardella, J.J. Kavich, Dong Jik Kim, Phillipe Sainctavit, Philippe Ohresser, F. Gautier, Yves Henry, Guy Schmerber, Hervé Bulou, Olivier M. Bengone, Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Institut de minéralogie, de physique des matériaux et de cosmochimie (IMPMC), Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de recherche pour le développement [IRD] : UR206-Centre National de la Recherche Scientifique (CNRS), ICN2 - Institut Catala de Nanociencia i Nanotecnologia (ICN2), Universitat Autònoma de Barcelona (UAB), and Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)
Subjects: Physics, Condensed matter physics, Magnetic moment, Magnetic circular dichroism, Kondo effect, 02 engineering and technology, Atmospheric temperature range, 021001 nanoscience & nanotechnology, 01 natural sciences, Nuclear magnetic resonance, Impurity, 0103 physical sciences, Moment (physics), [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Condensed Matter::Strongly Correlated Electrons, Absorption (chemistry), 010306 general physics, 0210 nano-technology, Spin (physics)
Abstract: We use x-ray magnetic circular dichroism to evidence the effect of correlations on the local impurity magnetic moment in an archetypal Kondo system, namely, a dilute Cu:Fe alloy. Applying the sum rules on the Fe ${L}_{2,3}$ absorption edges, the evolution of the spin and orbital moments across the Kondo temperature are determined separately. The spin moment presents a crossover from a nearly temperature-independent regime below the Kondo temperature to a paramagneticlike regime above. Conversely, the weak orbital moment shows a temperature-independent behavior in the whole temperature range, suggesting different Kondo screening temperature scales for the spin and orbital moments.
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26 results on '"Fabrice Scheurer"'

1. Ultralow-temperature device dedicated to soft X-ray magnetic circular dichroism experiments

2. Magnetic phase and magneto-resistive effects in vanadium oxide epitaxial nanoclusters

3. High Spin Polarization at Ferromagnetic Metal–Organic Interfaces: A Generic Property

4. Electrofluorochromism at the single-molecule level

5. Fano Description of Single-Hydrocarbon Fluorescence Excited by a Scanning Tunneling Microscope

6. Linking Electronic Transport through a Spin Crossover Thin Film to the Molecular Spin State Using X-ray Absorption Spectroscopy Operando Techniques

7. Bright Electroluminescence from Single Graphene Nanoribbon Junctions

8. Cu Metal/Mn Phthalocyanine Organic Spinterfaces atop Co with High Spin Polarization at Room Temperature

9. Modulating the Ferromagnet/Molecule Spin Hybridization Using an Artificial Magnetoelectric

10. Vibronic Spectroscopy with Submolecular Resolution from STM-Induced Electroluminescence

11. Efficient Spin-Flip Excitation of a Nickelocene Molecule

12. Ordinary and Hot Electroluminescence from Single-Molecule Devices: Controlling the Emission Color by Chemical Engineering

13. Simple and advanced ferromagnet/molecule spinterfaces

14. Interface Magnetoelectric Coupling in Co/Pb(Zr,Ti)O3

15. Single molecules as whispering galleries for electrons

16. Low-Temperature Surface Diffusion on Metallic Surfaces

17. Narrow-line single-molecule transducer between electronic circuits and surface plasmons

18. Probing a Device's Active Atoms

19. Electroluminescence of a Polythiophene Molecular Wire Suspended between a Metallic Surface and the Tip of a Scanning Tunneling Microscope

20. Direct observation of a highly spin-polarized organic spinterface at room temperature

21. Thermodynamics versus kinetics in a morphology transition of nanoparticles

22. Spin magnetic moments from single atoms to small Cr clusters

23. Real-Time Monitoring of Growing Nanoparticles

24. Single-molecule tautomerization tracking through space- and time-resolved fluorescence spectroscopy

25. Energy funnelling within multichromophore architectures monitored with subnanometre resolution

26. Kondo screening of the spin and orbital magnetic moments of Fe impurities in Cu

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26 results on '"Fabrice Scheurer"'

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books, media & more in Jio Institute collections

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