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1. New binaries from the SHINE survey

Author

M. Bonavita, R. Gratton, S. Desidera, V. Squicciarini, V. D’Orazi, A. Zurlo, B. Biller, G. Chauvin, C. Fontanive, M. Janson, S. Messina, F. Menard, M. Meyer, A. Vigan, H. Avenhaus, R. Asensio Torres, J.-L. Beuzit, A. Boccaletti, M. Bonnefoy, W. Brandner, F. Cantalloube, A. Cheetham, M. Cudel, S. Daemgen, P. Delorme, C. Desgrange, C. Dominik, N. Engler, P. Feautrier, M. Feldt, R. Galicher, A. Garufi, D. Gasparri, C. Ginski, J. Girard, A. Grandjean, J. Hagelberg, T. Henning, S. Hunziker, M. Kasper, M. Keppler, E. Lagadec, A.-M. Lagrange, M. Langlois, J. Lannier, C. Lazzoni, H. Le Coroller, R. Ligi, M. Lombart, A.-L. Maire, S. Mazevet, D. Mesa, D. Mouillet, C. Moutou, A. Müller, S. Peretti, C. Perrot, S. Petrus, A. Potier, J. Ramos, E. Rickman, D. Rouan, G. Salter, M. Samland, T. Schmidt, E. Sissa, T. Stolker, J. Szulágyi, M. Turatto, S. Udry, F. Wildi, Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire de la Côte d'Azur (OCA), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Low Energy Astrophysics (API, FNWI), The Open University [Milton Keynes] (OU), INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Institute for Astronomy [Edinburgh] (IfA), University of Edinburgh, Department of Astronomy, Stockholm University, INAF - Osservatorio Astrofisico di Catania (OACT), Physikalisches Institut [Würzburg], Julius-Maximilians-Universität Würzburg [Wurtzbourg, Allemagne] (JMU), Universidad de Chile = University of Chile [Santiago] (UCHILE), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Geneva Observatory, Université de Genève = University of Geneva (UNIGE), Institute of Astronomy [ETH Zürich], Department of Physics [ETH Zürich] (D-PHYS), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), Universiteit van Amsterdam (UvA), Institute for Particle Physics and Astrophysics [ETH Zürich] (IPA), INAF - Osservatorio Astrofisico di Arcetri (OAA), Instituto de Astronomia y ciencias Planetarias de Atacama (INCT), Universidad de Atacama, Unité Scientifique de la Station de Nançay (USN), Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Observatoire de Paris, and Université Paris sciences et lettres (PSL)

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), [SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph], techniques: high angular resolution, FOS: Physical sciences, Astronomy and Astrophysics, binaries: visual, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics::Galaxy Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics - Earth and Planetary Astrophysics
Abstract

We present the multiple stellar systems observed within the SpHere INfrared survey for Exoplanet (SHINE). SHINE searched for substellar companions to young stars using high contrast imaging. Although stars with known stellar companions within SPHERE field of view (, 59 pages, 11 tables, 18 figures

Published
2021
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2. Triple-Point Fermions in Ferroelectric GeTe

Author

Milan Radovic, Ondřej Caha, J. Hugo Dil, Houke Chen, Laurent Nicolaï, J. Krempaský, Gunther Springholz, Martin Gmitra, E. B. Guedes, J. Minár, Mauro Fanciulli, Marco Caputo, Valentine V. Volobuev, Paul Scherrer Institute (PSI), New Technologies Research Centre [Plzeň] (NTC), University of West Bohemia [Plzeň ], Institute of Physics P. J. Šafárik University in Košice, Department of Physics, Tsinghua University (TSINGHUA UNIV.), Tsinghua University [Beijing] (THU), Laboratoire de Physique des Matériaux et des Surfaces (LPMS), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-CY Cergy Paris Université (CY), Physikalisches Institut [Würzburg], Julius-Maximilians-Universität Würzburg (JMU), Johannes Kepler Universität Linz - Johannes Kepler University Linz [Autriche] (JKU), Masaryk University [Brno] (MUNI), Johannes Kepler Universität Linz (JKU), and Ecole Polytechnique Fédérale de Lausanne (EPFL)

Subjects
Physics, Condensed Matter - Materials Science, Condensed matter physics, Triple point, Materials Science (cond-mat.mtrl-sci), FOS: Physical sciences, General Physics and Astronomy, Fermion, Lorentz covariance, 01 natural sciences, Symmetry (physics), Condensed Matter - Other Condensed Matter, Brillouin zone, 0103 physical sciences, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Condensed Matter::Strongly Correlated Electrons, Density functional theory, 010306 general physics, Electronic band structure, Other Condensed Matter (cond-mat.other), Spin-½
Abstract

Ferroelectric GeTe is unveiled to exhibit an intriguing multiple non-trivial topology of the electronic band structure due to the existence of triple-point and type-II Weyl fermions, which goes well beyond the giant Rashba spin splitting controlled by external fields as previously reported. Using spin- and angle-resolved photoemission spectroscopy combined with ab initio density functional theory, the unique spin texture around the triple point caused by the crossing of one spin degenerate and two spin-split bands along the ferroelectric crystal axis is derived. This consistently reveals spin winding numbers that are coupled with time reversal symmetry and Lorentz invariance, which are found to be equal for both triple-point pairs in the Brillouin zone. The rich manifold of effects opens up promising perspectives for studying non-trivial phenomena and multi-component fermions in condensed matter systems., 5 pages, 5 figures

Published
2020

3. Four-wave mixing dynamics of a strongly coupled quantum-dot–microcavity system driven by up to 20 photons

Author

Martin Kamp, Jacek Kasprzak, Christian Schneider, Tilmann Kuhn, Kevin Jürgens, Daniel Groll, Daniel Wigger, Thilo Hahn, Sven Höfling, Physikalisches Institut [Münster], Westfälische Wilhelms-Universität Münster (WWU), Physikalisches Institut [Würzburg], Julius-Maximilians-Universität Würzburg [Wurtzbourg, Allemagne] (JMU), Nanophysique et Semiconducteurs (NPSC), Institut Néel (NEEL), Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), University of St Andrews. Condensed Matter Physics, and University of St Andrews. School of Physics and Astronomy

Subjects
Photon, T-NDAS, FOS: Physical sciences, Physics::Optics, 02 engineering and technology, 01 natural sciences, Signal, Four-wave mixing, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), 0103 physical sciences, 010306 general physics, Spectroscopy, QC, Mixing (physics), Physics, Condensed Matter - Mesoscale and Nanoscale Physics, Oscillation, Relaxation (NMR), 021001 nanoscience & nanotechnology, QC Physics, Quantum dot, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Atomic physics, 0210 nano-technology, Physics - Optics, Optics (physics.optics)
Abstract

D.W. acknowledges financial support by the Polish National Agency for Academic Exchange (NAWA) within the ULAM program (No. PPN/ULM/2019/1/00064). The Würzburg team acknowledges the support by the State of Bavaria and the Deutsche Forschungsgemeinschaft (DFG) within Project No. SCHN1376 5.1 / PR1749 1.1. The Jaynes-Cummings (JC) model represents one of the simplest ways in which single qubits can interact with single photon modes, leading to profound quantum phenomena like superpositions of light and matter states. One system, that can be described with the JC model, is a single quantum dot embedded in a micropillar cavity. In this joint experimental and theoretical study we investigate such a system using four-wave mixing (FWM) micro-spectroscopy. Special emphasis is laid on the dependence of the FWM signals on the number of photons injected into the microcavity. By comparing simulation and experiment, which are in excellent agreement with each other, we infer that up to ∼20 photons take part in the observed FWM dynamics. Thus we verify the validity of the JC model for the system under consideration in this non-trivial regime. We find that the inevitable coupling between the quantum dot exciton and longitudinal acoustic phonons of the host lattice influences the real time FWM dynamics and has to be taken into account for a sufficient description of the quantum dot-microcavity system. Performing additional simulations in an idealized dissipation-less regime, we observe that the FWM signal exhibits quasi-periodic dynamics, analog to the collapse and revival phenomenon of the JC model. In these simulations we also see that the FWM spectrum has a triplet structure, if a large number of photons is injected into the cavity. Postprint

Published
2020

4. Acoustic phonon sideband dynamics during polaron formation in a single quantum dot

Author

Jacek Kasprzak, Martin Kamp, Vage Karakhanyan, Daniel Wigger, Christian Schneider, Paweł Machnikowski, Tilmann Kuhn, Sven Höfling, University of St Andrews. Condensed Matter Physics, University of St Andrews. School of Physics and Astronomy, Physikalisches Institut [Münster], Westfälische Wilhelms-Universität Münster (WWU), Nanophysique et Semiconducteurs (NPSC), Institut Néel (NEEL), Centre National de la Recherche Scientifique (CNRS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA)-Université Grenoble Alpes (UGA), Physikalisches Institut [Würzburg], Julius-Maximilians-Universität Würzburg [Wurtzbourg, Allemagne] (JMU), and Wroclaw University of Science and Technology

Subjects
Phonon, Exciton, T-NDAS, FOS: Physical sciences, Physics::Optics, 02 engineering and technology, Polaron, 01 natural sciences, Molecular physics, 010309 optics, Four-wave mixing, Optics, 0103 physical sciences, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), QC, Physics, Condensed Matter - Mesoscale and Nanoscale Physics, business.industry, 021001 nanoscience & nanotechnology, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Atomic and Molecular Physics, and Optics, QC Physics, Quantum dot, Picosecond, Excited state, Quasiparticle, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], 0210 nano-technology, business, Physics - Optics, Optics (physics.optics)
Abstract

When an electron-hole pair is optically excited in a semiconductor quantum dot the host crystal lattice needs to adapt to the presence of the generated charge distribution. Therefore the coupled exciton-phonon system has to establish a new equilibrium, which is reached in the form of a quasiparticle called polaron. Especially, when the exciton is abruptly generated on a timescale faster than the typical lattice dynamics, the lattice displacement cannot follow adiabatically. Consequently, a rich dynamics on the picosecond timescale of the coupled system is expected. In this study we combine simulations and measurements of the ultrafast, coherent, nonlinear optical response, obtained by four-wave mixing spectroscopy, to resolve the formation of this polaron. By detecting and investigating the phonon sidebands in the four-wave mixing spectra for varying pulse delays and different temperatures we have access to the influence of phonon emission and absorption processes which finally result in the emission of an acoustic wave packet out from the quantum dot., Comment: accepted in Optics Letters

Published
2020

5. Dynamical separation of bulk and edge transport in HgTe-based 2D topological insulators

Author

Dartiailh, Matthieu C., Hartinger, Simon, Gourmelon, Alexandre, Bendias, Kalle, Bartolomei, Hugo, Kamata, Hiroshi, Berroir, Jean-Marc, Fève, Gwendal, Plaçais, Bernard, Lunczer, Lukas, Schlereth, Raimund, Buhmann, Hartmut, Molenkamp, Laurens W., Bocquillon, Erwann, Physique Mésoscopique, Laboratoire de physique de l'ENS - ENS Paris (LPENS (UMR_8023)), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP), Fédération de recherche du Département de physique de l'Ecole Normale Supérieure - ENS Paris (FRDPENS), Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Physikalisches Institut [Würzburg], Julius-Maximilians-Universität Würzburg [Wurtzbourg, Allemagne] (JMU), Laboratoire de physique de l'ENS - ENS Paris (LPENS), Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Sorbonne Université (SU)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Sorbonne Université (SU)-École normale supérieure - Paris (ENS Paris), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)

Subjects
[PHYS]Physics [physics], Condensed Matter - Mesoscale and Nanoscale Physics, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), FOS: Physical sciences, [PHYS.COND.CM-MSQHE]Physics [physics]/Condensed Matter [cond-mat]/Mesoscopic Systems and Quantum Hall Effect [cond-mat.mes-hall]
Abstract

Topological effects in edge states are clearly visible on short lengths only, thus largely impeding their studies. On larger distances, one may be able to dynamically enhance topological signatures by exploiting the high mobility of edge states with respect to bulk carriers. Our work on microwave spectroscopy highlights the responses of the edges which host very mobile carriers, while bulk carriers are drastically slowed down in the gap. Though the edges are denser than expected, we establish that charge relaxation occurs on short timescales, and suggests that edge states can be addressed selectively on timescales over which bulk carriers are frozen., Comment: Main text (5 pages, 4 figures) + Supplementary Material

Published
2019
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6. Two-dimensional semiconductors in the regime of strong light-matter coupling

Author

Mikhail M. Glazov, Bernhard Urbaszek, Christian Schneider, Tobias Korn, Sven Höfling, Physikalisches Institut [Würzburg], Julius-Maximilians-Universität Würzburg (JMU), A.F. Ioffe Physical-Technical Institute, Russian Academy of Sciences [Moscow] (RAS), Institut für experimentelle und angewandte Physik [Regensburg], Universität Regensburg (UR), Laboratoire de physique et chimie des nano-objets (LPCNO), 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)-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Julius-Maximilians-Universität Würzburg [Wurtzbourg, Allemagne] (JMU), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), 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), and 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)

Subjects
Field (physics), Oscillator strength, Science, Exciton, FOS: Physical sciences, General Physics and Astronomy, Physics::Optics, 02 engineering and technology, Review Article, 01 natural sciences, General Biochemistry, Genetics and Molecular Biology, Condensed Matter::Materials Science, Mesoscale and Nanoscale Physics (cond-mat.mes-hall), 0103 physical sciences, [CHIM]Chemical Sciences, 010306 general physics, Condensed Matter::Quantum Gases, Physics, [PHYS.PHYS.PHYS-OPTICS]Physics [physics]/Physics [physics]/Optics [physics.optics], Condensed Matter - Materials Science, Multidisciplinary, Condensed matter physics, Condensed Matter - Mesoscale and Nanoscale Physics, Condensed Matter::Other, business.industry, Optical physics, Materials Science (cond-mat.mtrl-sci), Resonance, General Chemistry, 021001 nanoscience & nanotechnology, Condensed Matter::Mesoscopic Systems and Quantum Hall Effect, Transition metal dichalcogenide monolayers, Coupling (physics), Semiconductor, 0210 nano-technology, business
Abstract

The optical properties of transition metal dichalcogenide monolayers are widely dominated by excitons, Coulomb-bound electron-hole pairs. These quasi-particles exhibit giant oscillator strength and give rise to narrow-band, well-pronounced optical transitions, which can be brought into resonance with electromagnetic fields in microcavities and plasmonic nanostructures. Due to the atomic thinness and robustness of the monolayers, their integration in van der Waals heterostructures provides unique opportunities for engineering strong light-matter coupling. We review first results in this emerging field and outline future opportunities and challenges., 10 pages, 3 figures, short review, submitted version

Published
2017

7. Optimal control of vortex core polarity by resonant microwave pulses

Author

Olivier Klein, F. Lochner, Laurens W. Molenkamp, Benjamin Pigeau, Andreas Riegler, Georg Schmidt, Gregoire de Loubens, 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), Experimentelle Physik III [Würzburg] (EP3), Physikalisches Institut [Würzburg], Julius-Maximilians-Universität Würzburg (JMU)-Julius-Maximilians-Universität Würzburg (JMU), and Julius-Maximilians-Universität Würzburg [Wurtzbourg, Allemagne] (JMU)-Julius-Maximilians-Universität Würzburg [Wurtzbourg, Allemagne] (JMU)

Subjects
Physics, Condensed Matter - Materials Science, Condensed matter physics, Polarity (physics), Plane (geometry), Materials Science (cond-mat.mtrl-sci), FOS: Physical sciences, General Physics and Astronomy, 02 engineering and technology, Vorticity, Dissipation, 021001 nanoscience & nanotechnology, 01 natural sciences, Vortex, Core (optical fiber), Magnetization, Coherent control, 0103 physical sciences, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], 010306 general physics, 0210 nano-technology
Abstract

In magnetic nanostructures, the core of a vortex points either up or down, and the polarity can be reversed by alternating-field pulses. An experiment now demonstrates deterministic and coherent control of vortex-core polarity using sequences of resonant microwave pulses and highlights routes to optimizing the technique, which might find application in magnetic-storage devices. In a vortex-state magnetic nanodisc1,2,3, the static magnetization curls in the plane, except in the core region, where it points out of plane4,5, either up or down, leading to two possible stable states of opposite core polarity p. Dynamical reversal of p by large-amplitude motion of the vortex core6,7,8,9 has recently been demonstrated experimentally10,11,12,13,14, raising the prospect of practical applications, in particular in magnetic-storage devices15. Here we demonstrate coherent control of p by single- and double-microwave-pulse sequences, taking advantage of the resonant vortex dynamics in a perpendicular-bias magnetic field16. Experimental optimization of the microwave-pulse duration required for switching p also yields information about the characteristic decay time of the vortex core in the large-oscillation regime. This time is found to be less than half the length seen in the small-oscillation regime, suggesting a nonlinear behaviour of magnetic dissipation.

Published
2011

8. A Frequency-Controlled Magnetic Vortex Memory

Author

V. S. Tiberkevich, Benjamin Pigeau, Olivier Klein, A. Riegler, Andrei Slavin, Laurens W. Molenkamp, Georg Schmidt, G. de Loubens, F. Lochner, 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), Experimentelle Physik III [Würzburg] (EP3), Physikalisches Institut [Würzburg], Julius-Maximilians-Universität Würzburg (JMU)-Julius-Maximilians-Universität Würzburg (JMU), Department of Physics [Rochester], Oakland University, ANR-09-NANO-0006,VOICE,Dynamique de vortex magnétiques isolés ou en interaction induite par transfert de spin.(2009), and Julius-Maximilians-Universität Würzburg [Wurtzbourg, Allemagne] (JMU)-Julius-Maximilians-Universität Würzburg [Wurtzbourg, Allemagne] (JMU)

Subjects
Physics and Astronomy (miscellaneous), MRFM, Polarity (physics), FOS: Physical sciences, Magnetic resonance force microscopy, 02 engineering and technology, Rotation, 01 natural sciences, magnetic resonance, 0103 physical sciences, 010306 general physics, Physics, Condensed Matter - Materials Science, Condensed matter physics, Materials Science (cond-mat.mtrl-sci), 021001 nanoscience & nanotechnology, magnetic vortex, Magnetic field, Vortex, Core (optical fiber), magnetic resonance force microscopy, resonant reversal, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Magnetic force microscope, 0210 nano-technology, Microwave
Abstract

International audience; Using the ultra low damping NiMnSb half-Heusler alloy patterned into vortex-state magnetic nano-dots, we demonstrate a new concept of non-volatile memory controlled by the frequency. A perpendicular bias magnetic field is used to split the frequency of the vortex core gyrotropic rotation into two distinct frequencies, depending on the sign of the vortex core polarity $p=\pm1$ inside the dot. A magnetic resonance force microscope and microwave pulses applied at one of these two resonant frequencies allow for local and deterministic addressing of binary information (core polarity).

Published
2010

9. Bistability of vortex core dynamics in a single perpendicularly magnetized nanodisk

Author

Andrei Slavin, Nicolas Vukadinovic, Benjamin Pigeau, Hervé Hurdequint, F. Boust, A. Riegler, G. de Loubens, Konstantin Y. Guslienko, F. Lochner, Georg Schmidt, V. S. Tiberkevich, Laurens W. Molenkamp, Olivier Klein, 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), Experimentelle Physik III [Würzburg] (EP3), Physikalisches Institut [Würzburg], Julius-Maximilians-Universität Würzburg [Wurtzbourg, Allemagne] (JMU)-Julius-Maximilians-Universität Würzburg [Wurtzbourg, Allemagne] (JMU), ONERA - The French Aerospace Lab [Toulouse], ONERA, Department of Materials Physics, The University of the Basque Country, 20080 San Sebastian, Laboratoire de Physique des Solides (LPS), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Sud - Paris 11 (UP11), Department of Physics [Rochester], Oakland University, Service Electromagnétisme et Infrarouge (GGT/DTIAE), Dassault Aviation, This research was partially supported by the ANR PNANO06-0235 from France, by the European Grant DynaMax (FP6-IST 033749), by the MURI Grant No. W911NF-04-1-0247 from the U.S. Army Research Office, by the Contract W56HZV-08-P-L605 from the U.S. Army TARDEC, RDECOM, and by the Grant No. ECCS-0653901 from the U.S. National Science Foundation., ANR-06-BLAN-0235,COUPLEMPLOI,Couples et emploi : une étude théorique et empirique du comportement des conjoints sur le marché du travail(2006), Julius-Maximilians-Universität Würzburg (JMU)-Julius-Maximilians-Universität Würzburg (JMU), and Université Paris-Sud - Paris 11 (UP11)-Centre National de la Recherche Scientifique (CNRS)

Subjects
MRFM, Bistability, FOS: Physical sciences, General Physics and Astronomy, Magnetic resonance force microscopy, 02 engineering and technology, 01 natural sciences, 0103 physical sciences, PACS numbers : 76.50.+g, 68.37.Rt, 75.75.+a, 010306 general physics, Physics, Condensed Matter - Materials Science, Condensed matter physics, Materials Science (cond-mat.mtrl-sci), 021001 nanoscience & nanotechnology, Ferromagnetic resonance, magnetic vortex, Vortex, Magnetic field, ferromagnetic resonance, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Rotational spectroscopy, Magnetic force microscope, 0210 nano-technology, Magnetic reactance
Abstract

Microwave spectroscopy of individual vortex-state magnetic nano-disks in a perpendicular bias magnetic field, $H$, is performed using a magnetic resonance force microscope (MRFM). It reveals the splitting induced by $H$ on the gyrotropic frequency of the vortex core rotation related to the existence of the two stable polarities of the core. This splitting enables spectroscopic detection of the core polarity. The bistability extends up to a large negative (antiparallel to the core) value of the bias magnetic field $H_r$, at which the core polarity is reversed. The difference between the frequencies of the two stable rotational modes corresponding to each core polarity is proportional to $H$ and to the ratio of the disk thickness to its radius. Simple analytic theory in combination with micromagnetic simulations give quantitative description of the observed bistable dynamics., 4 pages, 3 figures, 1 table, 16 references. Submitted to Physical Review Letters on December 19th, 2008

Published
2008

10. Surface Diffusion of Cr Adatoms on Au(111) by Quantum Tunneling

Author

Emilie Gaudry, Hervé Bulou, I. Chado, J. Faerber, Philippe Ohresser, F. Scheurer, Christine Boeglin, Sarnjeet S. Dhesi, B. Lazarovits, Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Institut de Physique et Chimie des Matériaux de Strasbourg (IPCMS), Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), European Synchrotron Radiation Facility (ESRF), 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), Center for Computational Materials Science [Wien], Technical University of Vienna [Vienna] (TU WIEN), Institut de minéralogie et de physique des milieux condensés (IMPMC), Université Pierre et Marie Curie - Paris 6 (UPMC)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Physikalisches Institut [Würzburg], Julius-Maximilians-Universität Würzburg [Wurtzbourg, Allemagne] (JMU), 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), Vienna University of Technology (TU Wien), Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Paris Diderot - Paris 7 (UPD7)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), Julius-Maximilians-Universität Würzburg (JMU), 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 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
Surface diffusion, Materials science, Condensed matter physics, Magnetic circular dichroism, Monte Carlo method, Nucleation, General Physics and Astronomy, 02 engineering and technology, 021001 nanoscience & nanotechnology, 01 natural sciences, Spectral line shape, 0103 physical sciences, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], Orders of magnitude (data), Diffusion (business), 010306 general physics, 0210 nano-technology, Quantum tunnelling
Abstract

International audience; The low-temperature surface diffusion of isolated Cr adatoms on Au(111) has been determined using nonperturbing x rays. Changes in the x-ray magnetic circular dichroism spectral line shape together with Monte Carlo calculations demonstrate that adatom nucleation proceeds via quantum tunneling diffusion rather than over-barrier hopping for temperatures

Published
2005

11. Interferences of Ultrashort Free Electron Wave Packets

Author

Matthias Wollenhaupt, M. A. Bouchene, Gustav Gerber, Sébastien Zamith, A. Flettner, Bertrand Girard, Ch. Sarpe-Tudoran, Thomas Baumert, Andreas Assion, D. Liese, U. Weichmann, Universität Kassel [Kassel], Femto (LCAR), Laboratoire Collisions Agrégats Réactivité (LCAR), Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Centre National de la Recherche Scientifique (CNRS)-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), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées, Théorie (LCAR), Physikalisches Institut [Würzburg], Julius-Maximilians-Universität Würzburg [Wurtzbourg, Allemagne] (JMU), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-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 Recherche sur les Systèmes Atomiques et Moléculaires Complexes (IRSAMC), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Institut National des Sciences Appliquées - Toulouse (INSA Toulouse), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National des Sciences Appliquées - Toulouse (INSA Toulouse)

Subjects
Free electron model, Physics, [PHYS.PHYS.PHYS-ATOM-PH]Physics [physics]/Physics [physics]/Atomic Physics [physics.atom-ph], Wave packet, Above threshold ionization, General Physics and Astronomy, Physics::Optics, 02 engineering and technology, Photoionization, Electron, 021001 nanoscience & nanotechnology, Laser, 01 natural sciences, law.invention, law, Ionization, 0103 physical sciences, Femtosecond, Physics::Atomic and Molecular Clusters, Physics::Atomic Physics, Atomic physics, 010306 general physics, 0210 nano-technology, 32.80.Qk, 32.80.Rm, 42.50.Md
Abstract

International audience; Interferences of free electron wave packets generated by a pair of identical, time-delayed, femtosecond laser pulses which ionize excited atomic potassium have been observed. Two different schemes are investigated: threshold electrons produced by one-photon ionization with parallel laser polarization and above threshold ionization electrons produced by a two-photon transition with crossed laser polarization. Our results show that the temporal coherence of light pulses is transferred to free electron wave packets, thus opening the door to a whole variety of exciting experiments.

Published
2002

12. Monitoring the He+ ion channel formation by high-order harmonic generation.

Author

Seres J, Seres E, and Spielmann C

Abstract

The macroscopic build-up of the high-order harmonic signal depends on the free electron density in the generation medium. The free electrons affect the harmonic yield and spectral shape through modifying the refractive index and the phase matching conditions. These dependences allow studying the He(+) ion channel formation in a He gas jet. The evolution of an ion channel created by an ultrashort laser pulse via optical field ionization was monitored using the harmonic signal generated by a collinear propagating second laser pulse. From the measured high harmonic signal as function of the delay we are able to gain information about the free electron density. Under our experimental condition, the ion channel has been fully formed 300 fs after the first laser pulse, resulting in an enhancement of harmonic yield of the second laser pulse by two orders of magnitude.

Published
2009
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13. Fast method for 1D non-cartesian parallel imaging using GRAPPA.

Author

Heidemann RM, Griswold MA, Seiberlich N, Nittka M, Kannengiesser SA, Kiefer B, and Jakob PM

Subjects
Artifacts, Humans, Magnetic Resonance Imaging instrumentation, Phantoms, Imaging, Brain Mapping methods, Image Processing, Computer-Assisted methods, Magnetic Resonance Imaging methods
Abstract

MRI with non-Cartesian sampling schemes can offer inherent advantages. Radial acquisitions are known to be very robust, even in the case of vast undersampling. This is also true for 1D non-Cartesian MRI, in which the center of k-space is oversampled or at least sampled at the Nyquist rate. There are two main reasons for the more relaxed foldover artifact behavior: First, due to the oversampling of the center, high-energy foldover artifacts originating from the center of k-space are avoided. Second, due to the non-equidistant sampling of k-space, the corresponding field of view (FOV) is no longer well defined. As a result, foldover artifacts are blurred over a broad range and appear less severe. The more relaxed foldover artifact behavior and the densely sampled central k-space make trajectories of this type an ideal complement to autocalibrated parallel MRI (pMRI) techniques, such as generalized autocalibrating partially parallel acquisitions (GRAPPA). Although pMRI can benefit from non-Cartesian trajectories, this combination has not yet entered routine clinical use. One of the main reasons for this is the need for long reconstruction times due to the complex calculations necessary for non-Cartesian pMRI. In this work it is shown that one can significantly reduce the complexity of the calculations by exploiting a few specific properties of k-space-based pMRI.

Published
2007
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14. Resolution enhancement in lung 1H imaging using parallel imaging methods.

Author

Heidemann RM, Griswold MA, Kiefer B, Nittka M, Wang J, Jellus V, and Jakob PM

Subjects
Humans, Image Enhancement methods, Lung anatomy & histology, Magnetic Resonance Imaging methods
Abstract

Resolution in (1)H lung imaging is limited mainly by the acquisition time. Today, half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequences, with short echo time (TE) and short interecho spacing (T(inter)) have found increased use in lung imaging. In this study, a HASTE sequence was used in combination with a partially parallel acquisition (PPA) strategy to increase the spatial resolution in single-shot (1)H lung imaging. To investigate the benefits of using a combination of single-shot sequences and PPA, five healthy volunteers were examined. Compared to conventional imaging methods, substantially increased resolution is obtained using the PPA approach. Representative in vivo (1)H lung images acquired with a HASTE sequence in combination with the generalized autocalibrating partially parallel acquisition (GRAPPA) method, up to an acceleration factor of three, are presented., (Copyright 2003 Wiley-Liss, Inc.)

Published
2003
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15. Generalized autocalibrating partially parallel acquisitions (GRAPPA).

Author

Griswold MA, Jakob PM, Heidemann RM, Nittka M, Jellus V, Wang J, Kiefer B, and Haase A

Subjects
Algorithms, Calibration, Computer Simulation, Humans, Models, Theoretical, Image Processing, Computer-Assisted methods, Magnetic Resonance Imaging methods
Abstract

In this study, a novel partially parallel acquisition (PPA) method is presented which can be used to accelerate image acquisition using an RF coil array for spatial encoding. This technique, GeneRalized Autocalibrating Partially Parallel Acquisitions (GRAPPA) is an extension of both the PILS and VD-AUTO-SMASH reconstruction techniques. As in those previous methods, a detailed, highly accurate RF field map is not needed prior to reconstruction in GRAPPA. This information is obtained from several k-space lines which are acquired in addition to the normal image acquisition. As in PILS, the GRAPPA reconstruction algorithm provides unaliased images from each component coil prior to image combination. This results in even higher SNR and better image quality since the steps of image reconstruction and image combination are performed in separate steps. After introducing the GRAPPA technique, primary focus is given to issues related to the practical implementation of GRAPPA, including the reconstruction algorithm as well as analysis of SNR in the resulting images. Finally, in vivo GRAPPA images are shown which demonstrate the utility of the technique., (Copyright 2002 Wiley-Liss, Inc.)

Published
2002
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