1
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Gołębiewski M, Hertel R, d'Aquino M, Vasyuchka V, Weiler M, Pirro P, Krawczyk M, Fukami S, Ohno H, Llandro J. Collective Spin-Wave Dynamics in Gyroid Ferromagnetic Nanostructures. ACS Appl Mater Interfaces 2024. [PMID: 38648102 DOI: 10.1021/acsami.4c02366] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2024]
Abstract
Expanding upon the burgeoning discipline of magnonics, this research elucidates the intricate dynamics of spin waves (SWs) within three-dimensional nanoenvironments. It marks a shift from traditionally used planar systems to exploration of magnetization configurations and the resulting dynamics within 3D nanostructures. This study deploys micromagnetic simulations alongside ferromagnetic resonance measurements to scrutinize magnetic gyroids, periodic chiral configurations composed of chiral triple junctions with a period in nanoscale. Our findings uncover distinctive attributes intrinsic to the gyroid network, most notably the localization of collective SW excitations and the sensitivity of the gyroid's ferromagnetic response to the orientation of the static magnetic field, a correlation closely tied to the crystallographic alignment of the structure. Furthermore, we show that for the ferromagnetic resonance, multidomain gyroid films can be treated as a magnonic material with effective magnetization scaled by its filling factor. The implications of our research carry the potential for practical uses such as an effective, metamaterial-like substitute for ferromagnetic parts and lay the groundwork for radio frequency filters. The growing areas of 3D magnonics and spintronics present exciting opportunities to investigate and utilize gyroid nanostructures for signal processing purposes.
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Affiliation(s)
- Mateusz Gołębiewski
- Institute of Spintronics and Quantum Information, Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznańskiego 2, 61-614 Poznań, Poland
| | - Riccardo Hertel
- Université de Strasbourg, CNRS, Institut de Physique et Chimie des Matériaux de Strasbourg, F-67000 Strasbourg, France
| | - Massimiliano d'Aquino
- Department of Electrical Engineering and ICT, University of Naples Federico II, 80125 Naples, Italy
| | - Vitaliy Vasyuchka
- Fachbereich Physik und Landesforschungszentrum OPTIMAS, Rheinland-Pfälzische Technische Universität Kaiserslautern-Landau, Erwin-Schrödinger-Straße 56, 67663 Kaiserslautern, Germany
| | - Mathias Weiler
- Fachbereich Physik und Landesforschungszentrum OPTIMAS, Rheinland-Pfälzische Technische Universität Kaiserslautern-Landau, Erwin-Schrödinger-Straße 56, 67663 Kaiserslautern, Germany
| | - Philipp Pirro
- Fachbereich Physik und Landesforschungszentrum OPTIMAS, Rheinland-Pfälzische Technische Universität Kaiserslautern-Landau, Erwin-Schrödinger-Straße 56, 67663 Kaiserslautern, Germany
| | - Maciej Krawczyk
- Institute of Spintronics and Quantum Information, Faculty of Physics, Adam Mickiewicz University, Uniwersytetu Poznańskiego 2, 61-614 Poznań, Poland
| | - Shunsuke Fukami
- Research Institute of Electrical Communication (RIEC), Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai-shi, Miyagi 980-8577, Japan
- Center for Science and Innovation in Spintronics (CSIS), Tohoku University, 980-8577 Sendai, Japan
- Center for Innovative Integrated Electronic Systems (CIES), Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, 980-0845 Sendai, Japan
- WPI Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, 980-8577 Sendai, Japan
- Inamori Research Institute for Science, 600-8411 Kyoto, Japan
| | - Hideo Ohno
- Research Institute of Electrical Communication (RIEC), Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai-shi, Miyagi 980-8577, Japan
- Center for Science and Innovation in Spintronics (CSIS), Tohoku University, 980-8577 Sendai, Japan
- Center for Innovative Integrated Electronic Systems (CIES), Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, 980-0845 Sendai, Japan
- WPI Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, 980-8577 Sendai, Japan
| | - Justin Llandro
- Research Institute of Electrical Communication (RIEC), Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai-shi, Miyagi 980-8577, Japan
- Center for Science and Innovation in Spintronics (CSIS), Tohoku University, 980-8577 Sendai, Japan
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2
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Abdelrahman D, Iseli R, Musya M, Jinnai B, Fukami S, Yuasa T, Sai H, Wiesner UB, Saba M, Wilts BD, Steiner U, Llandro J, Gunkel I. Directed Self-Assembly of Diamond Networks in Triblock Terpolymer Films on Patterned Substrates. ACS Appl Mater Interfaces 2023; 15:57981-57991. [PMID: 37989271 PMCID: PMC10739600 DOI: 10.1021/acsami.3c10619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 10/13/2023] [Accepted: 10/17/2023] [Indexed: 11/23/2023]
Abstract
Block copolymers (BCPs) are particularly effective in creating soft nanostructured templates for transferring complex 3D network structures into inorganic materials that are difficult to fabricate by other methods. However, achieving control of the local ordering within these 3D networks over large areas remains a significant obstacle to advancing material properties. Here, we address this challenge by directing the self-assembly of a 3D alternating diamond morphology by solvent vapor annealing of a triblock terpolymer film on a chemically patterned substrate. The hexagonal substrate patterns were designed to match a (111) plane of the diamond lattice. Commensurability between the sparse substrate pattern and the BCP lattice produced a uniformly ordered diamond network within the polymer film, as confirmed by a combination of atomic force microscopy and cross-sectional imaging using focused ion beam scanning electron microscopy. The successful replication of the complex and well-ordered 3D network structure in gold promises to advance optical metamaterials and has potential applications in nanophotonics.
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Affiliation(s)
- Doha Abdelrahman
- Adolphe
Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland
| | - René Iseli
- Adolphe
Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland
| | - Michimasa Musya
- Laboratory
for Nanoelectronics and Spintronics, Research
Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira,
Aoba-ku, Sendai 980-8577, Japan
| | - Butsurin Jinnai
- WPI
Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira,
Aoba-ku, Sendai 980-8577, Japan
| | - Shunsuke Fukami
- Laboratory
for Nanoelectronics and Spintronics, Research
Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira,
Aoba-ku, Sendai 980-8577, Japan
- WPI
Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira,
Aoba-ku, Sendai 980-8577, Japan
- Center
for Science and Innovation in Spintronics, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center
for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845, Japan
- Inamori
Research Institute for Science, Kyoto 600-8411, Japan
| | - Takeshi Yuasa
- Department
of Materials Science and Engineering, Cornell
University, 214 Bard Hall, Ithaca, New
York 14853-1501, United States
| | - Hiroaki Sai
- Department
of Materials Science and Engineering, Cornell
University, 214 Bard Hall, Ithaca, New
York 14853-1501, United States
| | - Ulrich B. Wiesner
- Department
of Materials Science and Engineering, Cornell
University, 214 Bard Hall, Ithaca, New
York 14853-1501, United States
| | - Matthias Saba
- Adolphe
Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland
- Swiss
National Center of Competence in Research (NCCR) Bio-Inspired Materials, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland
| | - Bodo D. Wilts
- Adolphe
Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland
- Department
of Chemistry and Physics of Materials, University
of Salzburg, Jakob-Haringer-Str. 2a, Salzburg 5020, Austria
- Swiss
National Center of Competence in Research (NCCR) Bio-Inspired Materials, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland
| | - Ullrich Steiner
- Adolphe
Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland
- Swiss
National Center of Competence in Research (NCCR) Bio-Inspired Materials, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland
| | - Justin Llandro
- Laboratory
for Nanoelectronics and Spintronics, Research
Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira,
Aoba-ku, Sendai 980-8577, Japan
- Center
for Science and Innovation in Spintronics, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Ilja Gunkel
- Adolphe
Merkle Institute, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland
- Swiss
National Center of Competence in Research (NCCR) Bio-Inspired Materials, University of Fribourg, Chemin des Verdiers 4, 1700 Fribourg, Switzerland
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3
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Yoon JY, Zhang P, Chou CT, Takeuchi Y, Uchimura T, Hou JT, Han J, Kanai S, Ohno H, Fukami S, Liu L. Handedness anomaly in a non-collinear antiferromagnet under spin-orbit torque. Nat Mater 2023; 22:1106-1113. [PMID: 37537356 DOI: 10.1038/s41563-023-01620-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 06/23/2023] [Indexed: 08/05/2023]
Abstract
Non-collinear antiferromagnets are an emerging family of spintronic materials because they not only possess the general advantages of antiferromagnets but also enable more advanced functionalities. Recently, in an intriguing non-collinear antiferromagnet Mn3Sn, where the octupole moment is defined as the collective magnetic order parameter, spin-orbit torque (SOT) switching has been achieved in seemingly the same protocol as in ferromagnets. Nevertheless, it is fundamentally important to explore the unknown octupole moment dynamics and contrast it with the magnetization vector of ferromagnets. Here we report a handedness anomaly in the SOT-driven dynamics of Mn3Sn: when spin current is injected, the octupole moment rotates in the opposite direction to the individual moments, leading to a SOT switching polarity distinct from ferromagnets. By using second-harmonic and d.c. magnetometry, we track the SOT effect onto the octupole moment during its rotation and reveal that the handedness anomaly stems from the interactions between the injected spin and the unique chiral-spin structure of Mn3Sn. We further establish the torque balancing equation of the magnetic octupole moment and quantify the SOT efficiency. Our finding provides a guideline for understanding and implementing the electrical manipulation of non-collinear antiferromagnets, which in nature differs from the well-established collinear magnets.
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Affiliation(s)
- Ju-Young Yoon
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai, Japan
- Graduate School of Engineering, Tohoku University, Sendai, Japan
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Pengxiang Zhang
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Chung-Tao Chou
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA
- Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Yutaro Takeuchi
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai, Japan
| | - Tomohiro Uchimura
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai, Japan
- Graduate School of Engineering, Tohoku University, Sendai, Japan
| | - Justin T Hou
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Jiahao Han
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai, Japan.
| | - Shun Kanai
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai, Japan
- Graduate School of Engineering, Tohoku University, Sendai, Japan
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, Sendai, Japan
- Division for the Establishment of Frontier Sciences of Organization for Advanced Studies, Tohoku University, Sendai, Japan
| | - Hideo Ohno
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai, Japan
- Graduate School of Engineering, Tohoku University, Sendai, Japan
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, Sendai, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, Sendai, Japan
| | - Shunsuke Fukami
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai, Japan.
- Graduate School of Engineering, Tohoku University, Sendai, Japan.
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai, Japan.
- Center for Science and Innovation in Spintronics, Tohoku University, Sendai, Japan.
- Center for Innovative Integrated Electronic Systems, Tohoku University, Sendai, Japan.
- Inamori Research Institute for Science, Kyoto, Japan.
| | - Luqiao Liu
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA.
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4
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Abstract
Antiferromagnets have attracted extensive interest as a material platform in spintronics. So far, antiferromagnet-enabled spin-orbitronics, spin-transfer electronics and spin caloritronics have formed the bases of antiferromagnetic spintronics. Spin transport and manipulation based on coherent antiferromagnetic dynamics have recently emerged, pushing the developing field of antiferromagnetic spintronics towards a new stage distinguished by the features of spin coherence. In this Review, we categorize and analyse the critical effects that harness the coherence of antiferromagnets for spintronic applications, including spin pumping from monochromatic antiferromagnetic magnons, spin transmission via phase-correlated antiferromagnetic magnons, electrically induced spin rotation and ultrafast spin-orbit effects in antiferromagnets. We also discuss future opportunities in research and applications stimulated by the principles, materials and phenomena of coherent antiferromagnetic spintronics.
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Affiliation(s)
- Jiahao Han
- Research Institute of Electrical Communication, Tohoku University, Sendai, Japan.
| | - Ran Cheng
- Department of Electrical and Computer Engineering, University of California Riverside, Riverside, CA, USA
- Department of Physics and Astronomy, University of California Riverside, Riverside, CA, USA
| | - Luqiao Liu
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Hideo Ohno
- Research Institute of Electrical Communication, Tohoku University, Sendai, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, Sendai, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, Sendai, Japan
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai, Japan
| | - Shunsuke Fukami
- Research Institute of Electrical Communication, Tohoku University, Sendai, Japan.
- Center for Science and Innovation in Spintronics, Tohoku University, Sendai, Japan.
- Center for Innovative Integrated Electronic Systems, Tohoku University, Sendai, Japan.
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai, Japan.
- Inamori Research Institute of Science, Kyoto, Japan.
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5
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Abe H, Abe S, Acciari VA, Aniello T, Ansoldi S, Antonelli LA, Arbet Engels A, Arcaro C, Artero M, Asano K, Baack D, Babić A, Baquero A, Barres de Almeida U, Barrio JA, Batković I, Baxter J, Becerra González J, Bednarek W, Bernardini E, Bernardos M, Berti A, Besenrieder J, Bhattacharyya W, Bigongiari C, Biland A, Blanch O, Bonnoli G, Bošnjak Ž, Burelli I, Busetto G, Carosi R, Carretero-Castrillo M, Ceribella G, Chai Y, Chilingarian A, Cikota S, Colombo E, Contreras JL, Cortina J, Covino S, D'Amico G, D'Elia V, Da Vela P, Dazzi F, De Angelis A, De Lotto B, Del Popolo A, Delfino M, Delgado J, Delgado Mendez C, Depaoli D, Di Pierro F, Di Venere L, Do Souto Espiñeira E, Dominis Prester D, Donini A, Dorner D, Doro M, Elsaesser D, Emery G, Fallah Ramazani V, Fariña L, Fattorini A, Font L, Fruck C, Fukami S, Fukazawa Y, García López RJ, Garczarczyk M, Gasparyan S, Gaug M, Giesbrecht Paiva JG, Giglietto N, Giordano F, Gliwny P, Godinović N, Green JG, Green D, Hadasch D, Hahn A, Hassan T, Heckmann L, Herrera J, Hrupec D, Hütten M, Imazawa R, Inada T, Iotov R, Ishio K, Jiménez Martínez I, Jormanainen J, Kerszberg D, Kobayashi Y, Kubo H, Kushida J, Lamastra A, Lelas D, Leone F, Lindfors E, Linhoff L, Lombardi S, Longo F, López-Coto R, López-Moya M, López-Oramas A, Loporchio S, Lorini A, Lyard E, Machado de Oliveira Fraga B, Majumdar P, Makariev M, Maneva G, Mang N, Manganaro M, Mangano S, Mannheim K, Mariotti M, Martínez M, Mas Aguilar A, Mazin D, Menchiari S, Mender S, Mićanović S, Miceli D, Miener T, Miranda JM, Mirzoyan R, Molina E, Mondal HA, Moralejo A, Morcuende D, Moreno V, Nakamori T, Nanci C, Nava L, Neustroev V, Nievas Rosillo M, Nigro C, Nilsson K, Nishijima K, Njoh Ekoume T, Noda K, Nozaki S, Ohtani Y, Oka T, Otero-Santos J, Paiano S, Palatiello M, Paneque D, Paoletti R, Paredes JM, Pavletić L, Persic M, Pihet M, Podobnik F, Prada Moroni PG, Prandini E, Principe G, Priyadarshi C, Puljak I, Rhode W, Ribó M, Rico J, Righi C, Rugliancich A, Sahakyan N, Saito T, Sakurai S, Satalecka K, Saturni FG, Schleicher B, Schmidt K, Schmuckermaier F, Schubert JL, Schweizer T, Sitarek J, Sliusar V, Sobczynska D, Spolon A, Stamerra A, Strišković J, Strom D, Strzys M, Suda Y, Surić T, Takahashi M, Takeishi R, Tavecchio F, Temnikov P, Terauchi K, Terzić T, Teshima M, Tosti L, Truzzi S, Tutone A, Ubach S, van Scherpenberg J, Vazquez Acosta M, Ventura S, Verguilov V, Viale I, Vigorito CF, Vitale V, Vovk I, Walter R, Will M, Wunderlich C, Yamamoto T, Zarić D, Hiroshima N, Kohri K. Search for Gamma-Ray Spectral Lines from Dark Matter Annihilation up to 100 TeV toward the Galactic Center with MAGIC. Phys Rev Lett 2023; 130:061002. [PMID: 36827578 DOI: 10.1103/physrevlett.130.061002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 11/02/2022] [Accepted: 12/15/2022] [Indexed: 06/18/2023]
Abstract
Linelike features in TeV γ rays constitute a "smoking gun" for TeV-scale particle dark matter and new physics. Probing the Galactic Center region with ground-based Cherenkov telescopes enables the search for TeV spectral features in immediate association with a dense dark matter reservoir at a sensitivity out of reach for satellite γ-ray detectors, and direct detection and collider experiments. We report on 223 hours of observations of the Galactic Center region with the MAGIC stereoscopic telescope system reaching γ-ray energies up to 100 TeV. We improved the sensitivity to spectral lines at high energies using large-zenith-angle observations and a novel background modeling method within a maximum-likelihood analysis in the energy domain. No linelike spectral feature is found in our analysis. Therefore, we constrain the cross section for dark matter annihilation into two photons to ⟨σv⟩≲5×10^{-28} cm^{3} s^{-1} at 1 TeV and ⟨σv⟩≲1×10^{-25} cm^{3} s^{-1} at 100 TeV, achieving the best limits to date for a dark matter mass above 20 TeV and a cuspy dark matter profile at the Galactic Center. Finally, we use the derived limits for both cuspy and cored dark matter profiles to constrain supersymmetric wino models.
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Affiliation(s)
- H Abe
- Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR), The University of Tokyo, Kashiwa, 277-8582 Chiba, Japan
| | - S Abe
- Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR), The University of Tokyo, Kashiwa, 277-8582 Chiba, Japan
| | - V A Acciari
- Instituto de Astrofísica de Canarias and Departamento de Astrofísica, Universidad de La Laguna, E-38200 La Laguna, Tenerife, Spain
| | - T Aniello
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - S Ansoldi
- Università di Udine and INFN Trieste, I-33100 Udine, Italy
| | - L A Antonelli
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - A Arbet Engels
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - C Arcaro
- Università di Padova and INFN, I-35131 Padova, Italy
| | - M Artero
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - K Asano
- Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR), The University of Tokyo, Kashiwa, 277-8582 Chiba, Japan
| | - D Baack
- Technische Universität Dortmund, D-44221 Dortmund, Germany
| | - A Babić
- Croatian MAGIC Group: University of Zagreb, Faculty of Electrical Engineering and Computing (FER), 10000 Zagreb, Croatia
| | - A Baquero
- IPARCOS Institute and EMFTEL Department, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | - U Barres de Almeida
- Centro Brasileiro de Pesquisas Físicas (CBPF), 22290-180 URCA, Rio de Janeiro (RJ), Brazil
| | - J A Barrio
- IPARCOS Institute and EMFTEL Department, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | - I Batković
- Università di Padova and INFN, I-35131 Padova, Italy
| | - J Baxter
- Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR), The University of Tokyo, Kashiwa, 277-8582 Chiba, Japan
| | - J Becerra González
- Instituto de Astrofísica de Canarias and Departamento de Astrofísica, Universidad de La Laguna, E-38200 La Laguna, Tenerife, Spain
| | - W Bednarek
- University of Lodz, Faculty of Physics and Applied Informatics, Department of Astrophysics, 90-236 Lodz, Poland
| | - E Bernardini
- Università di Padova and INFN, I-35131 Padova, Italy
| | - M Bernardos
- Instituto de Astrofísica de Andalucía-CSIC, Glorieta de la Astronomía s/n, 18008 Granada, Spain
| | - A Berti
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - J Besenrieder
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - W Bhattacharyya
- Deutsches Elektronen-Synchrotron (DESY), D-15738 Zeuthen, Germany
| | - C Bigongiari
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - A Biland
- ETH Zürich, CH-8093 Zürich, Switzerland
| | - O Blanch
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - G Bonnoli
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - Ž Bošnjak
- Croatian MAGIC Group: University of Zagreb, Faculty of Electrical Engineering and Computing (FER), 10000 Zagreb, Croatia
| | - I Burelli
- Università di Udine and INFN Trieste, I-33100 Udine, Italy
| | - G Busetto
- Università di Padova and INFN, I-35131 Padova, Italy
| | - R Carosi
- Università di Pisa and INFN Pisa, I-56126 Pisa, Italy
| | | | - G Ceribella
- Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR), The University of Tokyo, Kashiwa, 277-8582 Chiba, Japan
| | - Y Chai
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - A Chilingarian
- Armenian MAGIC Group: A. Alikhanyan National Science Laboratory, 0036 Yerevan, Armenia
| | - S Cikota
- Croatian MAGIC Group: University of Zagreb, Faculty of Electrical Engineering and Computing (FER), 10000 Zagreb, Croatia
| | - E Colombo
- Instituto de Astrofísica de Canarias and Departamento de Astrofísica, Universidad de La Laguna, E-38200 La Laguna, Tenerife, Spain
| | - J L Contreras
- IPARCOS Institute and EMFTEL Department, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | - J Cortina
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas, E-28040 Madrid, Spain
| | - S Covino
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - G D'Amico
- Department for Physics and Technology, University of Bergen, Norway
| | - V D'Elia
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - P Da Vela
- Università di Pisa and INFN Pisa, I-56126 Pisa, Italy
| | - F Dazzi
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - A De Angelis
- Università di Padova and INFN, I-35131 Padova, Italy
| | - B De Lotto
- Università di Udine and INFN Trieste, I-33100 Udine, Italy
| | - A Del Popolo
- INFN MAGIC Group: INFN Sezione di Catania and Dipartimento di Fisica e Astronomia, University of Catania, I-95123 Catania, Italy
| | - M Delfino
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - J Delgado
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - C Delgado Mendez
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas, E-28040 Madrid, Spain
| | - D Depaoli
- INFN MAGIC Group: INFN Sezione di Torino and Università degli Studi di Torino, I-10125 Torino, Italy
| | - F Di Pierro
- INFN MAGIC Group: INFN Sezione di Torino and Università degli Studi di Torino, I-10125 Torino, Italy
| | - L Di Venere
- INFN MAGIC Group: INFN Sezione di Bari and Dipartimento Interateneo di Fisica dell'Università e del Politecnico di Bari, I-70125 Bari, Italy
| | - E Do Souto Espiñeira
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - D Dominis Prester
- Croatian MAGIC Group: University of Rijeka, Department of Physics, 51000 Rijeka, Croatia
| | - A Donini
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - D Dorner
- Universität Würzburg, D-97074 Würzburg, Germany
| | - M Doro
- Università di Padova and INFN, I-35131 Padova, Italy
| | - D Elsaesser
- Technische Universität Dortmund, D-44221 Dortmund, Germany
| | - G Emery
- University of Geneva, Chemin d'Ecogia 16, CH-1290 Versoix, Switzerland
| | - V Fallah Ramazani
- Finnish MAGIC Group: Finnish Centre for Astronomy with ESO, University of Turku, FI-20014 Turku, Finland
| | - L Fariña
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - A Fattorini
- Technische Universität Dortmund, D-44221 Dortmund, Germany
| | - L Font
- Departament de Física, and CERES-IEEC, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Spain
| | - C Fruck
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - S Fukami
- ETH Zürich, CH-8093 Zürich, Switzerland
| | - Y Fukazawa
- Japanese MAGIC Group: Physics Program, Graduate School of Advanced Science and Engineering, Hiroshima University, 739-8526 Hiroshima, Japan
| | - R J García López
- Instituto de Astrofísica de Canarias and Departamento de Astrofísica, Universidad de La Laguna, E-38200 La Laguna, Tenerife, Spain
| | - M Garczarczyk
- Deutsches Elektronen-Synchrotron (DESY), D-15738 Zeuthen, Germany
| | - S Gasparyan
- Armenian MAGIC Group: ICRANet-Armenia at NAS RA, 0019 Yerevan, Armenia
| | - M Gaug
- Departament de Física, and CERES-IEEC, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Spain
| | - J G Giesbrecht Paiva
- Centro Brasileiro de Pesquisas Físicas (CBPF), 22290-180 URCA, Rio de Janeiro (RJ), Brazil
| | - N Giglietto
- INFN MAGIC Group: INFN Sezione di Bari and Dipartimento Interateneo di Fisica dell'Università e del Politecnico di Bari, I-70125 Bari, Italy
| | - F Giordano
- INFN MAGIC Group: INFN Sezione di Bari and Dipartimento Interateneo di Fisica dell'Università e del Politecnico di Bari, I-70125 Bari, Italy
| | - P Gliwny
- University of Lodz, Faculty of Physics and Applied Informatics, Department of Astrophysics, 90-236 Lodz, Poland
| | - N Godinović
- Croatian MAGIC Group: University of Split, Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture (FESB), 21000 Split, Croatia
| | - J G Green
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - D Green
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - D Hadasch
- Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR), The University of Tokyo, Kashiwa, 277-8582 Chiba, Japan
| | - A Hahn
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - T Hassan
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas, E-28040 Madrid, Spain
| | - L Heckmann
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - J Herrera
- Instituto de Astrofísica de Canarias and Departamento de Astrofísica, Universidad de La Laguna, E-38200 La Laguna, Tenerife, Spain
| | - D Hrupec
- Croatian MAGIC Group: Josip Juraj Strossmayer University of Osijek, Department of Physics, 31000 Osijek, Croatia
| | - M Hütten
- Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR), The University of Tokyo, Kashiwa, 277-8582 Chiba, Japan
| | - R Imazawa
- Japanese MAGIC Group: Physics Program, Graduate School of Advanced Science and Engineering, Hiroshima University, 739-8526 Hiroshima, Japan
| | - T Inada
- Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR), The University of Tokyo, Kashiwa, 277-8582 Chiba, Japan
| | - R Iotov
- Universität Würzburg, D-97074 Würzburg, Germany
| | - K Ishio
- University of Lodz, Faculty of Physics and Applied Informatics, Department of Astrophysics, 90-236 Lodz, Poland
| | - I Jiménez Martínez
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas, E-28040 Madrid, Spain
| | - J Jormanainen
- Finnish MAGIC Group: Finnish Centre for Astronomy with ESO, University of Turku, FI-20014 Turku, Finland
| | - D Kerszberg
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - Y Kobayashi
- Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR), The University of Tokyo, Kashiwa, 277-8582 Chiba, Japan
| | - H Kubo
- Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR), The University of Tokyo, Kashiwa, 277-8582 Chiba, Japan
| | - J Kushida
- Japanese MAGIC Group: Department of Physics, Tokai University, Hiratsuka, 259-1292 Kanagawa, Japan
| | - A Lamastra
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - D Lelas
- Croatian MAGIC Group: University of Split, Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture (FESB), 21000 Split, Croatia
| | - F Leone
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - E Lindfors
- Finnish MAGIC Group: Finnish Centre for Astronomy with ESO, University of Turku, FI-20014 Turku, Finland
| | - L Linhoff
- Technische Universität Dortmund, D-44221 Dortmund, Germany
| | - S Lombardi
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - F Longo
- Università di Udine and INFN Trieste, I-33100 Udine, Italy
| | - R López-Coto
- Università di Padova and INFN, I-35131 Padova, Italy
| | - M López-Moya
- IPARCOS Institute and EMFTEL Department, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | - A López-Oramas
- Instituto de Astrofísica de Canarias and Departamento de Astrofísica, Universidad de La Laguna, E-38200 La Laguna, Tenerife, Spain
| | - S Loporchio
- INFN MAGIC Group: INFN Sezione di Bari and Dipartimento Interateneo di Fisica dell'Università e del Politecnico di Bari, I-70125 Bari, Italy
| | - A Lorini
- Università di Siena and INFN Pisa, I-53100 Siena, Italy
| | - E Lyard
- University of Geneva, Chemin d'Ecogia 16, CH-1290 Versoix, Switzerland
| | | | - P Majumdar
- Saha Institute of Nuclear Physics, A CI of Homi Bhabha National Institute, Kolkata 700064, West Bengal, India
| | - M Makariev
- Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, BG-1784 Sofia, Bulgaria
| | - G Maneva
- Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, BG-1784 Sofia, Bulgaria
| | - N Mang
- Technische Universität Dortmund, D-44221 Dortmund, Germany
| | - M Manganaro
- Croatian MAGIC Group: University of Rijeka, Department of Physics, 51000 Rijeka, Croatia
| | - S Mangano
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas, E-28040 Madrid, Spain
| | - K Mannheim
- Universität Würzburg, D-97074 Würzburg, Germany
| | - M Mariotti
- Università di Padova and INFN, I-35131 Padova, Italy
| | - M Martínez
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - A Mas Aguilar
- IPARCOS Institute and EMFTEL Department, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | - D Mazin
- Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR), The University of Tokyo, Kashiwa, 277-8582 Chiba, Japan
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - S Menchiari
- Università di Siena and INFN Pisa, I-53100 Siena, Italy
| | - S Mender
- Technische Universität Dortmund, D-44221 Dortmund, Germany
| | - S Mićanović
- Croatian MAGIC Group: University of Rijeka, Department of Physics, 51000 Rijeka, Croatia
| | - D Miceli
- Università di Padova and INFN, I-35131 Padova, Italy
| | - T Miener
- IPARCOS Institute and EMFTEL Department, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | - J M Miranda
- Università di Siena and INFN Pisa, I-53100 Siena, Italy
| | - R Mirzoyan
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - E Molina
- Universitat de Barcelona, ICCUB, IEEC-UB, E-08028 Barcelona, Spain
| | - H A Mondal
- Saha Institute of Nuclear Physics, A CI of Homi Bhabha National Institute, Kolkata 700064, West Bengal, India
| | - A Moralejo
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - D Morcuende
- IPARCOS Institute and EMFTEL Department, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | - V Moreno
- Departament de Física, and CERES-IEEC, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Spain
| | - T Nakamori
- Japanese MAGIC Group: Department of Physics, Yamagata University, Yamagata 990-8560, Japan
| | - C Nanci
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - L Nava
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - V Neustroev
- Finnish MAGIC Group: Space Physics and Astronomy Research Unit, University of Oulu, FI-90014 Oulu, Finland
| | - M Nievas Rosillo
- Instituto de Astrofísica de Canarias and Departamento de Astrofísica, Universidad de La Laguna, E-38200 La Laguna, Tenerife, Spain
| | - C Nigro
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - K Nilsson
- Finnish MAGIC Group: Finnish Centre for Astronomy with ESO, University of Turku, FI-20014 Turku, Finland
| | - K Nishijima
- Japanese MAGIC Group: Department of Physics, Tokai University, Hiratsuka, 259-1292 Kanagawa, Japan
| | - T Njoh Ekoume
- Instituto de Astrofísica de Canarias and Departamento de Astrofísica, Universidad de La Laguna, E-38200 La Laguna, Tenerife, Spain
| | - K Noda
- Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR), The University of Tokyo, Kashiwa, 277-8582 Chiba, Japan
| | - S Nozaki
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - Y Ohtani
- Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR), The University of Tokyo, Kashiwa, 277-8582 Chiba, Japan
| | - T Oka
- Japanese MAGIC Group: Department of Physics, Kyoto University, 606-8502 Kyoto, Japan
| | - J Otero-Santos
- Instituto de Astrofísica de Canarias and Departamento de Astrofísica, Universidad de La Laguna, E-38200 La Laguna, Tenerife, Spain
| | - S Paiano
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - M Palatiello
- Università di Udine and INFN Trieste, I-33100 Udine, Italy
| | - D Paneque
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - R Paoletti
- Università di Siena and INFN Pisa, I-53100 Siena, Italy
| | - J M Paredes
- Universitat de Barcelona, ICCUB, IEEC-UB, E-08028 Barcelona, Spain
| | - L Pavletić
- Croatian MAGIC Group: University of Rijeka, Department of Physics, 51000 Rijeka, Croatia
| | - M Persic
- Università di Udine and INFN Trieste, I-33100 Udine, Italy
| | - M Pihet
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - F Podobnik
- Università di Siena and INFN Pisa, I-53100 Siena, Italy
| | | | - E Prandini
- Università di Padova and INFN, I-35131 Padova, Italy
| | - G Principe
- Università di Udine and INFN Trieste, I-33100 Udine, Italy
| | - C Priyadarshi
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - I Puljak
- Croatian MAGIC Group: University of Split, Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture (FESB), 21000 Split, Croatia
| | - W Rhode
- Technische Universität Dortmund, D-44221 Dortmund, Germany
| | - M Ribó
- Universitat de Barcelona, ICCUB, IEEC-UB, E-08028 Barcelona, Spain
| | - J Rico
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - C Righi
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - A Rugliancich
- Università di Pisa and INFN Pisa, I-56126 Pisa, Italy
| | - N Sahakyan
- Armenian MAGIC Group: ICRANet-Armenia at NAS RA, 0019 Yerevan, Armenia
| | - T Saito
- Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR), The University of Tokyo, Kashiwa, 277-8582 Chiba, Japan
| | - S Sakurai
- Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR), The University of Tokyo, Kashiwa, 277-8582 Chiba, Japan
| | - K Satalecka
- Finnish MAGIC Group: Finnish Centre for Astronomy with ESO, University of Turku, FI-20014 Turku, Finland
| | - F G Saturni
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | | | - K Schmidt
- Technische Universität Dortmund, D-44221 Dortmund, Germany
| | | | - J L Schubert
- Technische Universität Dortmund, D-44221 Dortmund, Germany
| | - T Schweizer
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - J Sitarek
- University of Lodz, Faculty of Physics and Applied Informatics, Department of Astrophysics, 90-236 Lodz, Poland
| | - V Sliusar
- University of Geneva, Chemin d'Ecogia 16, CH-1290 Versoix, Switzerland
| | - D Sobczynska
- University of Lodz, Faculty of Physics and Applied Informatics, Department of Astrophysics, 90-236 Lodz, Poland
| | - A Spolon
- Università di Padova and INFN, I-35131 Padova, Italy
| | - A Stamerra
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - J Strišković
- Croatian MAGIC Group: Josip Juraj Strossmayer University of Osijek, Department of Physics, 31000 Osijek, Croatia
| | - D Strom
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - M Strzys
- Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR), The University of Tokyo, Kashiwa, 277-8582 Chiba, Japan
| | - Y Suda
- Japanese MAGIC Group: Physics Program, Graduate School of Advanced Science and Engineering, Hiroshima University, 739-8526 Hiroshima, Japan
| | - T Surić
- Croatian MAGIC Group: Ruđer Bošković Institute, 10000 Zagreb, Croatia
| | - M Takahashi
- Japanese MAGIC Group: Institute for Space-Earth Environmental Research and Kobayashi-Maskawa Institute for the Origin of Particles and the Universe, Nagoya University, 464-6801 Nagoya, Japan
| | - R Takeishi
- Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR), The University of Tokyo, Kashiwa, 277-8582 Chiba, Japan
| | - F Tavecchio
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - P Temnikov
- Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, BG-1784 Sofia, Bulgaria
| | - K Terauchi
- Japanese MAGIC Group: Department of Physics, Kyoto University, 606-8502 Kyoto, Japan
| | - T Terzić
- Croatian MAGIC Group: University of Rijeka, Department of Physics, 51000 Rijeka, Croatia
| | - M Teshima
- Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR), The University of Tokyo, Kashiwa, 277-8582 Chiba, Japan
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - L Tosti
- INFN MAGIC Group: INFN Sezione di Perugia, I-06123 Perugia, Italy
| | - S Truzzi
- Università di Siena and INFN Pisa, I-53100 Siena, Italy
| | - A Tutone
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - S Ubach
- Departament de Física, and CERES-IEEC, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Spain
| | | | - M Vazquez Acosta
- Instituto de Astrofísica de Canarias and Departamento de Astrofísica, Universidad de La Laguna, E-38200 La Laguna, Tenerife, Spain
| | - S Ventura
- Università di Siena and INFN Pisa, I-53100 Siena, Italy
| | - V Verguilov
- Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, BG-1784 Sofia, Bulgaria
| | - I Viale
- Università di Padova and INFN, I-35131 Padova, Italy
| | - C F Vigorito
- INFN MAGIC Group: INFN Sezione di Torino and Università degli Studi di Torino, I-10125 Torino, Italy
| | - V Vitale
- INFN MAGIC Group: INFN Roma Tor Vergata, I-00133 Roma, Italy
| | - I Vovk
- Japanese MAGIC Group: Institute for Cosmic Ray Research (ICRR), The University of Tokyo, Kashiwa, 277-8582 Chiba, Japan
| | - R Walter
- University of Geneva, Chemin d'Ecogia 16, CH-1290 Versoix, Switzerland
| | - M Will
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - C Wunderlich
- Università di Siena and INFN Pisa, I-53100 Siena, Italy
| | - T Yamamoto
- Japanese MAGIC Group: Department of Physics, Konan University, Kobe, Hyogo 658-8501, Japan
| | - D Zarić
- Croatian MAGIC Group: University of Split, Faculty of Electrical Engineering, Mechanical Engineering and Naval Architecture (FESB), 21000 Split, Croatia
| | - N Hiroshima
- Department of Physics, University of Toyama, 3190 Gofuku, Toyama 930-8555, Japan
- RIKEN iTHEMS, Wako, Saitama 351-0198, Japan
| | - K Kohri
- Theory Center, IPNS, KEK, Tsukuba, Ibaraki 305-0801, Japan
- The Graduate University for Advanced Studies (SOKENDAI), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
- Kavli IPMU (WPI), UTIAS, The University of Tokyo, Kashiwa, Chiba 277-8583, Japan
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6
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Yamane Y, Fukami S, Ieda J. Theory of Emergent Inductance with Spin-Orbit Coupling Effects. Phys Rev Lett 2022; 128:147201. [PMID: 35476473 DOI: 10.1103/physrevlett.128.147201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 12/23/2021] [Accepted: 02/25/2022] [Indexed: 06/14/2023]
Abstract
We extend the theory of emergent inductance, which has recently been discovered in spiral magnets, to arbitrary magnetic textures by taking into account spin-orbit couplings arising in the absence of spatial inversion symmetry. We propose a new concept of spin-orbit emergent inductance, which can be formulated as originating from a dynamical Aharonov-Casher phase of an electron in ferromagnets. The spin-orbit emergent inductance universally arises in the coexistence of magnetism and the spin-orbit couplings, even with spatially uniform magnetization, allowing its stable operation in wide ranges of temperature and frequency. Revisiting the widely studied systems involving ferromagnets with spatial inversion asymmetry, with the new perspective offered by our work, will lead to opening a new paradigm in the study of spin-orbit physics and the spintronics-based power management in ultrawideband frequency range.
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Affiliation(s)
- Yuta Yamane
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai 980-8578, Japan
- Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577, Japan
| | - Shunsuke Fukami
- Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577, Japan
- Center for Spintronics Research Network, Tohoku University, Sendai 980-8577, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, Sendai 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, Sendai 980-0845, Japan
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
| | - Jun'ichi Ieda
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai 319-1195, Japan
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7
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Zahedinejad M, Fulara H, Khymyn R, Houshang A, Dvornik M, Fukami S, Kanai S, Ohno H, Åkerman J. Memristive control of mutual spin Hall nano-oscillator synchronization for neuromorphic computing. Nat Mater 2022; 21:81-87. [PMID: 34845363 DOI: 10.1038/s41563-021-01153-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 10/07/2021] [Indexed: 06/13/2023]
Abstract
Synchronization of large spin Hall nano-oscillator (SHNO) arrays is an appealing approach toward ultrafast non-conventional computing. However, interfacing to the array, tuning its individual oscillators and providing built-in memory units remain substantial challenges. Here, we address these challenges using memristive gating of W/CoFeB/MgO/AlOx-based SHNOs. In its high resistance state, the memristor modulates the perpendicular magnetic anisotropy at the CoFeB/MgO interface by the applied electric field. In its low resistance state the memristor adds or subtracts current to the SHNO drive. Both electric field and current control affect the SHNO auto-oscillation mode and frequency, allowing us to reversibly turn on/off mutual synchronization in chains of four SHNOs. We also demonstrate that two individually controlled memristors can be used to tune a four-SHNO chain into differently synchronized states. Memristor gating is therefore an efficient approach to input, tune and store the state of SHNO arrays for non-conventional computing models.
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Affiliation(s)
- Mohammad Zahedinejad
- Physics Department, University of Gothenburg, Gothenburg, Sweden
- NanOsc AB, Kista, Sweden
| | - Himanshu Fulara
- Physics Department, University of Gothenburg, Gothenburg, Sweden
- Department of Physics, Indian Institute of Technology Roorkee, Roorkee, India
| | - Roman Khymyn
- Physics Department, University of Gothenburg, Gothenburg, Sweden
| | - Afshin Houshang
- Physics Department, University of Gothenburg, Gothenburg, Sweden
| | | | - Shunsuke Fukami
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, Sendai, Japan
- Center for Spintronics Research Network, Tohoku University, Sendai, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, Sendai, Japan
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai, Japan
| | - Shun Kanai
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, Sendai, Japan
- Center for Spintronics Research Network, Tohoku University, Sendai, Japan
- Division for the Establishment of Frontier Sciences, Tohoku University, Sendai, Japan
| | - Hideo Ohno
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, Sendai, Japan
- Center for Spintronics Research Network, Tohoku University, Sendai, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, Sendai, Japan
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai, Japan
| | - Johan Åkerman
- Physics Department, University of Gothenburg, Gothenburg, Sweden.
- NanOsc AB, Kista, Sweden.
- Material and Nanophysics, School of Engineering Sciences, KTH Royal Institute of Technology, Kista, Sweden.
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8
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Takeuchi Y, Yamane Y, Yoon JY, Itoh R, Jinnai B, Kanai S, Ieda J, Fukami S, Ohno H. Chiral-spin rotation of non-collinear antiferromagnet by spin-orbit torque. Nat Mater 2021; 20:1364-1370. [PMID: 33986515 DOI: 10.1038/s41563-021-01005-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Accepted: 04/07/2021] [Indexed: 06/12/2023]
Abstract
Electrical manipulation of magnetic materials by current-induced spin torque constitutes the basis of spintronics. Here, we show an unconventional response to spin-orbit torque of a non-collinear antiferromagnet Mn3Sn, which has attracted attention owing to its large anomalous Hall effect despite a vanishingly small net magnetization. In epitaxial heavy-metal/Mn3Sn heterostructures, we observe a characteristic fluctuation of the Hall resistance under the application of electric current. This observation is explained by a rotation of the chiral-spin structure of Mn3Sn driven by spin-orbit torque. We find that the variation of the magnitude of anomalous Hall effect fluctuation with sample size correlates with the number of magnetic domains in the Mn3Sn layer. In addition, the dependence of the critical current on Mn3Sn layer thickness reveals that spin-orbit torque generated by small current densities, below 20 MA cm-2, effectively acts on the chiral-spin structure even in Mn3Sn layers that are thicker than 20 nm. The results provide additional pathways for electrical manipulation of magnetic materials.
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Affiliation(s)
- Yutaro Takeuchi
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Aoba-ku, Sendai, Japan.
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai, Japan.
| | - Yuta Yamane
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Aoba-ku, Sendai, Japan.
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, Sendai, Japan.
| | - Ju-Young Yoon
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Aoba-ku, Sendai, Japan
| | - Ryuichi Itoh
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Aoba-ku, Sendai, Japan
| | - Butsurin Jinnai
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai, Japan
| | - Shun Kanai
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Aoba-ku, Sendai, Japan
- Center for Spintronics Research Network, Tohoku University, Sendai, Japan
- Division for the Establishment of Frontier Sciences, Tohoku University, Sendai, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, Sendai, Japan
| | - Jun'ichi Ieda
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Aoba-ku, Sendai, Japan
- Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Japan
| | - Shunsuke Fukami
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Aoba-ku, Sendai, Japan.
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai, Japan.
- Center for Spintronics Research Network, Tohoku University, Sendai, Japan.
- Center for Science and Innovation in Spintronics, Tohoku University, Sendai, Japan.
- Center for Innovative Integrated Electronic Systems, Tohoku University, Sendai, Japan.
| | - Hideo Ohno
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Aoba-ku, Sendai, Japan
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai, Japan
- Center for Spintronics Research Network, Tohoku University, Sendai, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, Sendai, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, Sendai, Japan
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9
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Sharma R, Mishra R, Ngo T, Guo YX, Fukami S, Sato H, Ohno H, Yang H. Electrically connected spin-torque oscillators array for 2.4 GHz WiFi band transmission and energy harvesting. Nat Commun 2021; 12:2924. [PMID: 34006830 PMCID: PMC8131736 DOI: 10.1038/s41467-021-23181-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 04/20/2021] [Indexed: 12/28/2022] Open
Abstract
The mutual synchronization of spin-torque oscillators (STOs) is critical for communication, energy harvesting and neuromorphic applications. Short range magnetic coupling-based synchronization has spatial restrictions (few µm), whereas the long-range electrical synchronization using vortex STOs has limited frequency responses in hundreds MHz (<500 MHz), restricting them for on-chip GHz-range applications. Here, we demonstrate electrical synchronization of four non-vortex uniformly-magnetized STOs using a single common current source in both parallel and series configurations at 2.4 GHz band, resolving the frequency-area quandary for designing STO based on-chip communication systems. Under injection locking, synchronized STOs demonstrate an excellent time-domain stability and substantially improved phase noise performance. By integrating the electrically connected eight STOs, we demonstrate the battery-free energy-harvesting system by utilizing the wireless radio-frequency energy to power electronic devices such as LEDs. Our results highlight the significance of electrical topology (series vs. parallel) while designing an on-chip STOs system.
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Affiliation(s)
- Raghav Sharma
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore
| | - Rahul Mishra
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore
- Centre for Applied Research in Electronics, Indian Institute of Technology Delhi, New Delhi, India
| | - Tung Ngo
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore
| | - Yong-Xin Guo
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore
| | - Shunsuke Fukami
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Aoba, Sendai, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, Aoba, Sendai, Japan
- Center for Spintronics Research Network, Tohoku University, Aoba, Sendai, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, Sendai, Japan
- WPI Advanced Institute for Materials Research, Tohoku University, Aoba, Sendai, Japan
| | - Hideo Sato
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Aoba, Sendai, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, Aoba, Sendai, Japan
- Center for Spintronics Research Network, Tohoku University, Aoba, Sendai, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, Sendai, Japan
| | - Hideo Ohno
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Aoba, Sendai, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, Aoba, Sendai, Japan
- Center for Spintronics Research Network, Tohoku University, Aoba, Sendai, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, Sendai, Japan
- WPI Advanced Institute for Materials Research, Tohoku University, Aoba, Sendai, Japan
| | - Hyunsoo Yang
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore.
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10
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Hayakawa K, Kanai S, Funatsu T, Igarashi J, Jinnai B, Borders WA, Ohno H, Fukami S. Nanosecond Random Telegraph Noise in In-Plane Magnetic Tunnel Junctions. Phys Rev Lett 2021; 126:117202. [PMID: 33798384 DOI: 10.1103/physrevlett.126.117202] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 02/16/2021] [Indexed: 06/12/2023]
Abstract
We study the timescale of random telegraph noise (RTN) of nanomagnets in stochastic magnetic tunnel junctions (MTJs). From analytical and numerical calculations based on the Landau-Lifshitz-Gilbert and the Fokker-Planck equations, we reveal mechanisms governing the relaxation time of perpendicular easy-axis MTJs (p-MTJs) and in-plane easy-axis MTJs (i-MTJs), showing that i-MTJs can be made to have faster RTN. Superparamagnetic i-MTJs with small in-plane anisotropy and sizable perpendicular effective anisotropy show relaxation times down to 8 ns at negligible bias current, which is more than 5 orders of magnitude shorter than that of typical stochastic p-MTJs and about 100 times faster than the shortest time of i-MTJs reported so far. The findings give a new insight and foundation in developing stochastic MTJs for high-performance probabilistic computers.
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Affiliation(s)
- K Hayakawa
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577, Japan
| | - S Kanai
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577, Japan
- Division for the Establishment of Frontier Sciences, Organization for Advanced Studies, Tohoku University, Sendai 980-8577, Japan
- Center for Spintronics Research Network, Tohoku University, Sendai 980-8577, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, Sendai 980-8577, Japan
| | - T Funatsu
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577, Japan
| | - J Igarashi
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577, Japan
| | - B Jinnai
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
| | - W A Borders
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577, Japan
| | - H Ohno
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577, Japan
- Center for Spintronics Research Network, Tohoku University, Sendai 980-8577, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, Sendai 980-8577, Japan
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, Sendai 980-0845, Japan
| | - S Fukami
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai 980-8577, Japan
- Center for Spintronics Research Network, Tohoku University, Sendai 980-8577, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, Sendai 980-8577, Japan
- WPI-Advanced Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, Sendai 980-0845, Japan
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11
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Shao Q, Li P, Liu L, Yang H, Fukami S, Razavi A, Wu H, Wang K, Freimuth F, Mokrousov Y, Stiles MD, Emori S, Hoffmann A, Åkerman J, Roy K, Wang JP, Yang SH, Garello K, Zhang W. Roadmap of spin-orbit torques. IEEE Trans Magn 2021; 57:10.48550/arXiv.2104.11459. [PMID: 37057056 PMCID: PMC10091395 DOI: 10.48550/arxiv.2104.11459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Spin-orbit torque (SOT) is an emerging technology that enables the efficient manipulation of spintronic devices. The initial processes of interest in SOTs involved electric fields, spin-orbit coupling, conduction electron spins and magnetization. More recently interest has grown to include a variety of other processes that include phonons, magnons, or heat. Over the past decade, many materials have been explored to achieve a larger SOT efficiency. Recently, holistic design to maximize the performance of SOT devices has extended material research from a nonmagnetic layer to a magnetic layer. The rapid development of SOT has spurred a variety of SOT-based applications. In this Roadmap paper, we first review the theories of SOTs by introducing the various mechanisms thought to generate or control SOTs, such as the spin Hall effect, the Rashba-Edelstein effect, the orbital Hall effect, thermal gradients, magnons, and strain effects. Then, we discuss the materials that enable these effects, including metals, metallic alloys, topological insulators, two-dimensional materials, and complex oxides. We also discuss the important roles in SOT devices of different types of magnetic layers, such as magnetic insulators, antiferromagnets, and ferrimagnets. Afterward, we discuss device applications utilizing SOTs. We discuss and compare three-terminal and two-terminal SOT-magnetoresistive random-access memories (MRAMs); we mention various schemes to eliminate the need for an external field. We provide technological application considerations for SOT-MRAM and give perspectives on SOT-based neuromorphic devices and circuits. In addition to SOT-MRAM, we present SOT-based spintronic terahertz generators, nano-oscillators, and domain wall and skyrmion racetrack memories. This paper aims to achieve a comprehensive review of SOT theory, materials, and applications, guiding future SOT development in both the academic and industrial sectors.
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Affiliation(s)
- Qiming Shao
- Department of Electronic and Computer Engineering, Hong Kong University of Science and Technology
| | - Peng Li
- Department of Electrical and Computer Engineering, Auburn University
| | - Luqiao Liu
- Electrical Engineering and Computer Science, Massachusetts Institute of Technology
| | - Hyunsoo Yang
- Department of Electrical and Computer Engineering, National University of Singapore
| | - Shunsuke Fukami
- Research Institute of Electrical Communication, Tohoku University
| | - Armin Razavi
- Department of Electrical and Computer Engineering, University of California, Los Angeles
| | - Hao Wu
- Department of Electrical and Computer Engineering, University of California, Los Angeles
| | - Kang Wang
- Department of Electrical and Computer Engineering, University of California, Los Angeles
| | | | | | - Mark D Stiles
- Alternative Computing Group, National Institute of Standards and Technology
| | | | - Axel Hoffmann
- Department of Materials Science and Engineering, University of Illinois Urbana-Champaign
| | | | - Kaushik Roy
- Department of Electrical and Computer Engineering, Purdue University
| | - Jian-Ping Wang
- Electrical and Computer Engineering Department, University of Minnesota
| | | | - Kevin Garello
- IMEC, Leuven, Belgium; CEA-Spintec, Grenoble, France
| | - Wei Zhang
- Physics Department, Oakland University
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12
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Igarashi J, Remy Q, Iihama S, Malinowski G, Hehn M, Gorchon J, Hohlfeld J, Fukami S, Ohno H, Mangin S. Engineering Single-Shot All-Optical Switching of Ferromagnetic Materials. Nano Lett 2020; 20:8654-8660. [PMID: 33226825 DOI: 10.1021/acs.nanolett.0c03373] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Since it was recently demonstrated in a spin-valve structure, magnetization reversal of a ferromagnetic layer using a single ultrashort optical pulse has attracted attention for future ultrafast and energy-efficient magnetic storage or memory devices. However, the mechanism and the role of the magnetic properties of the ferromagnet as well as the time scale of the magnetization switching are not understood. Here, we investigate single-shot all-optical magnetization switching in a GdFeCo/Cu/[CoxNi1-x/Pt] spin-valve structure. We demonstrate that the threshold fluence for switching both the GdFeCo and the ferromagnetic layer depends on the laser pulse duration and the thickness and the Curie temperature of the ferromagnetic layer. We are able to explain most of the experimental results using a phenomenological model. This work provides a way to engineer ferromagnetic materials for energy efficient single-shot all-optical magnetization switching.
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Affiliation(s)
- Junta Igarashi
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan
- Institut Jean Lamour, UMR CNRS 7198, Université de Lorraine, Nancy 54011, France
| | - Quentin Remy
- Institut Jean Lamour, UMR CNRS 7198, Université de Lorraine, Nancy 54011, France
| | - Satoshi Iihama
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, 6-3 Aramaki Aza Aoba, Sendai 980-8578, Japan
- Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan
| | - Grégory Malinowski
- Institut Jean Lamour, UMR CNRS 7198, Université de Lorraine, Nancy 54011, France
| | - Michel Hehn
- Institut Jean Lamour, UMR CNRS 7198, Université de Lorraine, Nancy 54011, France
| | - Jon Gorchon
- Institut Jean Lamour, UMR CNRS 7198, Université de Lorraine, Nancy 54011, France
| | - Julius Hohlfeld
- Institut Jean Lamour, UMR CNRS 7198, Université de Lorraine, Nancy 54011, France
| | - Shunsuke Fukami
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan
- WPI Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan
- Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aramaki Aza Aoba, Sendai 980-0845, Japan
| | - Hideo Ohno
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan
- WPI Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan
- Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aramaki Aza Aoba, Sendai 980-0845, Japan
| | - Stéphane Mangin
- Institut Jean Lamour, UMR CNRS 7198, Université de Lorraine, Nancy 54011, France
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13
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Remy Q, Igarashi J, Iihama S, Malinowski G, Hehn M, Gorchon J, Hohlfeld J, Fukami S, Ohno H, Mangin S. Energy Efficient Control of Ultrafast Spin Current to Induce Single Femtosecond Pulse Switching of a Ferromagnet. Adv Sci (Weinh) 2020; 7:2001996. [PMID: 33304754 PMCID: PMC7709970 DOI: 10.1002/advs.202001996] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 08/10/2020] [Indexed: 05/23/2023]
Abstract
New methods to induce magnetization switching in a thin ferromagnetic material using femtosecond laser pulses without the assistance of an applied external magnetic field have recently attracted a lot of interest. It has been shown that by optically triggering the reversal of the magnetization in a GdFeCo layer, the magnetization of a nearby ferromagnetic thin film can also be reversed via spin currents originating in the GdFeCo layer. Here, using a similar structure, it is shown that the magnetization reversal of the GdFeCo is not required in order to reverse the magnetization of the ferromagnetic thin film. This switching is attributed to the ultrafast spin current and can be generated by the GdFeCo demagnetization. A larger energy efficiency of the ferromagnetic layer single pulse switching is obtained for a GdFeCo with a larger Gd concentration. Those ultrafast and energy efficient switchings observed in such spintronic devices open a new path toward ultrafast and energy efficient magnetic memories.
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Affiliation(s)
- Quentin Remy
- Université de LorraineInstitut Jean LamourUMR CNRSNancy7198France
| | - Junta Igarashi
- Laboratory for Nanoelectronics and SpintronicsResearch Institute of Electrical CommunicationTohoku University2‐1‐1 Katahira, AobaSendai980‐8577Japan
| | - Satoshi Iihama
- Frontier Research Institute for Interdisciplinary SciencesTohoku University6‐3 Aramaki Aza AobaSendai980‐8578Japan
- Center for Spintronics Research NetworkTohoku University2‐1‐1 Katahira, AobaSendai980‐8577Japan
| | | | - Michel Hehn
- Université de LorraineInstitut Jean LamourUMR CNRSNancy7198France
| | - Jon Gorchon
- Université de LorraineInstitut Jean LamourUMR CNRSNancy7198France
| | - Julius Hohlfeld
- Université de LorraineInstitut Jean LamourUMR CNRSNancy7198France
| | - Shunsuke Fukami
- Laboratory for Nanoelectronics and SpintronicsResearch Institute of Electrical CommunicationTohoku University2‐1‐1 Katahira, AobaSendai980‐8577Japan
- WPI Advanced Institute for Materials ResearchTohoku University2‐1‐1 Katahira, AobaSendai980‐8577Japan
- Center for Science and Innovation in SpintronicsTohoku University2‐1‐1 Katahira, AobaSendai980‐8577Japan
- Center for Spintronics Research NetworkTohoku University2‐1‐1 Katahira, AobaSendai980‐8577Japan
- Center for Innovative Integrated Electronic SystemsTohoku University468‐1 Aramaki Aza AobaSendai980‐0845Japan
| | - Hideo Ohno
- Laboratory for Nanoelectronics and SpintronicsResearch Institute of Electrical CommunicationTohoku University2‐1‐1 Katahira, AobaSendai980‐8577Japan
- WPI Advanced Institute for Materials ResearchTohoku University2‐1‐1 Katahira, AobaSendai980‐8577Japan
- Center for Science and Innovation in SpintronicsTohoku University2‐1‐1 Katahira, AobaSendai980‐8577Japan
- Center for Spintronics Research NetworkTohoku University2‐1‐1 Katahira, AobaSendai980‐8577Japan
- Center for Innovative Integrated Electronic SystemsTohoku University468‐1 Aramaki Aza AobaSendai980‐0845Japan
| | - Stéphane Mangin
- Université de LorraineInstitut Jean LamourUMR CNRSNancy7198France
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14
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DuttaGupta S, Kurenkov A, Tretiakov OA, Krishnaswamy G, Sala G, Krizakova V, Maccherozzi F, Dhesi SS, Gambardella P, Fukami S, Ohno H. Spin-orbit torque switching of an antiferromagnetic metallic heterostructure. Nat Commun 2020; 11:5715. [PMID: 33177506 PMCID: PMC7658218 DOI: 10.1038/s41467-020-19511-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Accepted: 10/14/2020] [Indexed: 11/09/2022] Open
Abstract
The ability to represent information using an antiferromagnetic material is attractive for future antiferromagnetic spintronic devices. Previous studies have focussed on the utilization of antiferromagnetic materials with biaxial magnetic anisotropy for electrical manipulation. A practical realization of these antiferromagnetic devices is limited by the requirement of material-specific constraints. Here, we demonstrate current-induced switching in a polycrystalline PtMn/Pt metallic heterostructure. A comparison of electrical transport measurements in PtMn with and without the Pt layer, corroborated by x-ray imaging, reveals reversible switching of the thermally-stable antiferromagnetic Néel vector by spin-orbit torques. The presented results demonstrate the potential of polycrystalline metals for antiferromagnetic spintronics.
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Affiliation(s)
- Samik DuttaGupta
- Center for Science and Innovation in Spintronics, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan. .,Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan. .,Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan.
| | - A Kurenkov
- Center for Science and Innovation in Spintronics, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan.,Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan.,Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
| | - Oleg A Tretiakov
- School of Physics, The University of New South Wales, Sydney, 2052, Australia
| | - G Krishnaswamy
- Laboratory for Magnetism and Interface Physics, Department of Materials, ETH Zurich, 8093, Zurich, Switzerland
| | - G Sala
- Laboratory for Magnetism and Interface Physics, Department of Materials, ETH Zurich, 8093, Zurich, Switzerland
| | - V Krizakova
- Laboratory for Magnetism and Interface Physics, Department of Materials, ETH Zurich, 8093, Zurich, Switzerland
| | - F Maccherozzi
- Diamond Light Source, Chilton, Didcot, Oxfordshire, OX11 0DE, United Kingdom
| | - S S Dhesi
- Diamond Light Source, Chilton, Didcot, Oxfordshire, OX11 0DE, United Kingdom
| | - P Gambardella
- Laboratory for Magnetism and Interface Physics, Department of Materials, ETH Zurich, 8093, Zurich, Switzerland
| | - S Fukami
- Center for Science and Innovation in Spintronics, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan.,Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan.,Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan.,Center for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, 980-0845, Japan.,WPI Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
| | - H Ohno
- Center for Science and Innovation in Spintronics, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan.,Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan.,Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan.,Center for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, 980-0845, Japan.,WPI Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
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15
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Fulara H, Zahedinejad M, Khymyn R, Dvornik M, Fukami S, Kanai S, Ohno H, Åkerman J. Giant voltage-controlled modulation of spin Hall nano-oscillator damping. Nat Commun 2020; 11:4006. [PMID: 32782243 PMCID: PMC7419544 DOI: 10.1038/s41467-020-17833-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 07/08/2020] [Indexed: 11/09/2022] Open
Abstract
Spin Hall nano-oscillators (SHNOs) are emerging spintronic devices for microwave signal generation and oscillator-based neuromorphic computing combining nano-scale footprint, fast and ultra-wide microwave frequency tunability, CMOS compatibility, and strong non-linear properties providing robust large-scale mutual synchronization in chains and two-dimensional arrays. While SHNOs can be tuned via magnetic fields and the drive current, neither approach is conducive to individual SHNO control in large arrays. Here, we demonstrate electrically gated W/CoFeB/MgO nano-constrictions in which the voltage-dependent perpendicular magnetic anisotropy tunes the frequency and, thanks to nano-constriction geometry, drastically modifies the spin-wave localization in the constriction region resulting in a giant 42% variation of the effective damping over four volts. As a consequence, the SHNO threshold current can be strongly tuned. Our demonstration adds key functionality to nano-constriction SHNOs and paves the way for energy-efficient control of individual oscillators in SHNO chains and arrays for neuromorphic computing.
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Affiliation(s)
- Himanshu Fulara
- Physics Department, University of Gothenburg, 412 96, Gothenburg, Sweden.
| | - Mohammad Zahedinejad
- Physics Department, University of Gothenburg, 412 96, Gothenburg, Sweden
- NanOsc AB, Electrum 229, 164 40, Kista, Sweden
| | - Roman Khymyn
- Physics Department, University of Gothenburg, 412 96, Gothenburg, Sweden
| | - Mykola Dvornik
- Physics Department, University of Gothenburg, 412 96, Gothenburg, Sweden
- NanOsc AB, Electrum 229, 164 40, Kista, Sweden
| | - Shunsuke Fukami
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, 980-0845, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- WPI-Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
| | - Shun Kanai
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
| | - Hideo Ohno
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, 980-0845, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- WPI-Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
| | - Johan Åkerman
- Physics Department, University of Gothenburg, 412 96, Gothenburg, Sweden.
- NanOsc AB, Electrum 229, 164 40, Kista, Sweden.
- Material and Nanophysics, School of Engineering Sciences, KTH Royal Institute of Technology, Electrum 229, 164 40, Kista, Sweden.
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16
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Acciari VA, Ansoldi S, Antonelli LA, Arbet Engels A, Baack D, Babić A, Banerjee B, Barres de Almeida U, Barrio JA, Becerra González J, Bednarek W, Bellizzi L, Bernardini E, Berti A, Besenrieder J, Bhattacharyya W, Bigongiari C, Biland A, Blanch O, Bonnoli G, Bošnjak Ž, Busetto G, Carosi R, Ceribella G, Cerruti M, Chai Y, Chilingarian A, Cikota S, Colak SM, Colin U, Colombo E, Contreras JL, Cortina J, Covino S, D'Amico G, D'Elia V, Da Vela P, Dazzi F, De Angelis A, De Lotto B, Delfino M, Delgado J, Depaoli D, Di Pierro F, Di Venere L, Do Souto Espiñeira E, Dominis Prester D, Donini A, Dorner D, Doro M, Elsaesser D, Fallah Ramazani V, Fattorini A, Ferrara G, Foffano L, Fonseca MV, Font L, Fruck C, Fukami S, García López RJ, Garczarczyk M, Gasparyan S, Gaug M, Giglietto N, Giordano F, Gliwny P, Godinović N, Green D, Hadasch D, Hahn A, Herrera J, Hoang J, Hrupec D, Hütten M, Inada T, Inoue S, Ishio K, Iwamura Y, Jouvin L, Kajiwara Y, Karjalainen M, Kerszberg D, Kobayashi Y, Kubo H, Kushida J, Lamastra A, Lelas D, Leone F, Lindfors E, Lombardi S, Longo F, López M, López-Coto R, López-Oramas A, Loporchio S, Machado de Oliveira Fraga B, Maggio C, Majumdar P, Makariev M, Mallamaci M, Maneva G, Manganaro M, Mannheim K, Maraschi L, Mariotti M, Martínez M, Mazin D, Mender S, Mićanović S, Miceli D, Miener T, Minev M, Miranda JM, Mirzoyan R, Molina E, Moralejo A, Morcuende D, Moreno V, Moretti E, Munar-Adrover P, Neustroev V, Nigro C, Nilsson K, Ninci D, Nishijima K, Noda K, Nogués L, Nozaki S, Ohtani Y, Oka T, Otero-Santos J, Palatiello M, Paneque D, Paoletti R, Paredes JM, Pavletić L, Peñil P, Perennes C, Peresano M, Persic M, Prada Moroni PG, Prandini E, Puljak I, Rhode W, Ribó M, Rico J, Righi C, Rugliancich A, Saha L, Sahakyan N, Saito T, Sakurai S, Satalecka K, Schleicher B, Schmidt K, Schweizer T, Sitarek J, Šnidarić I, Sobczynska D, Spolon A, Stamerra A, Strom D, Strzys M, Suda Y, Surić T, Takahashi M, Tavecchio F, Temnikov P, Terzić T, Teshima M, Torres-Albà N, Tosti L, van Scherpenberg J, Vanzo G, Vazquez Acosta M, Ventura S, Verguilov V, Vigorito CF, Vitale V, Vovk I, Will M, Zarić D, Nava L. Bounds on Lorentz Invariance Violation from MAGIC Observation of GRB 190114C. Phys Rev Lett 2020; 125:021301. [PMID: 32701326 DOI: 10.1103/physrevlett.125.021301] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 04/20/2020] [Accepted: 06/04/2020] [Indexed: 06/11/2023]
Abstract
On January 14, 2019, the Major Atmospheric Gamma Imaging Cherenkov telescopes detected GRB 190114C above 0.2 TeV, recording the most energetic photons ever observed from a gamma-ray burst. We use this unique observation to probe an energy dependence of the speed of light in vacuo for photons as predicted by several quantum gravity models. Based on a set of assumptions on the possible intrinsic spectral and temporal evolution, we obtain competitive lower limits on the quadratic leading order of speed of light modification.
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Affiliation(s)
- V A Acciari
- Instituto de Astrofísica de Canarias, E-38200 La Laguna, and Universidad de La Laguna, Departamento de Astrofísica, E-38206 La Laguna, Tenerife, Spain
| | - S Ansoldi
- Università di Udine, and INFN Trieste, I-33100 Udine, Italy
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
| | - L A Antonelli
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | | | - D Baack
- Technische Universität Dortmund, D-44221 Dortmund, Germany
| | - A Babić
- Croatian Consortium: University of Rijeka, Department of Physics, 51000 Rijeka; University of Split-FESB, 21000 Split; University of Zagreb-FER, 10000 Zagreb; University of Osijek, 31000 Osijek; Rudjer Boskovic Institute, 10000 Zagreb, Croatia
| | - B Banerjee
- Saha Institute of Nuclear Physics, HBNI, 1/AF Bidhannagar, Salt Lake, Sector-1, Kolkata 700064, India
| | - U Barres de Almeida
- Centro Brasileiro de Pesquisas Fsicas (CBPF), 22290-180 URCA, Rio de Janeiro (RJ), Brasil
| | - J A Barrio
- IPARCOS Institute and EMFTEL Department, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | - J Becerra González
- Instituto de Astrofísica de Canarias, E-38200 La Laguna, and Universidad de La Laguna, Departamento de Astrofísica, E-38206 La Laguna, Tenerife, Spain
| | - W Bednarek
- University of Lodz, Faculty of Physics and Applied Informatics, Department of Astrophysics, 90-236 Lodz, Poland
| | - L Bellizzi
- Università di Siena and INFN Pisa, I-53100 Siena, Italy
| | - E Bernardini
- Deutsches Elektronen-Synchrotron (DESY), D-15738 Zeuthen, Germany
- Università di Padova and INFN, I-35131 Padova, Italy
| | - A Berti
- Istituto Nazionale Fisica Nucleare (INFN), 00044 Frascati (Roma) Italy
| | - J Besenrieder
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - W Bhattacharyya
- Deutsches Elektronen-Synchrotron (DESY), D-15738 Zeuthen, Germany
| | - C Bigongiari
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - A Biland
- ETH Zurich, CH-8093 Zurich, Switzerland
| | - O Blanch
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - G Bonnoli
- Università di Siena and INFN Pisa, I-53100 Siena, Italy
| | - Ž Bošnjak
- Croatian Consortium: University of Rijeka, Department of Physics, 51000 Rijeka; University of Split-FESB, 21000 Split; University of Zagreb-FER, 10000 Zagreb; University of Osijek, 31000 Osijek; Rudjer Boskovic Institute, 10000 Zagreb, Croatia
| | - G Busetto
- Università di Padova and INFN, I-35131 Padova, Italy
| | - R Carosi
- Università di Pisa, and INFN Pisa, I-56126 Pisa, Italy
| | - G Ceribella
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - M Cerruti
- Universitat de Barcelona, ICCUB, IEEC-UB, E-08028 Barcelona, Spain
| | - Y Chai
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - A Chilingarian
- The Armenian Consortium: ICRANet-Armenia at NAS RA, A. Alikhanyan National Laboratory
| | - S Cikota
- Croatian Consortium: University of Rijeka, Department of Physics, 51000 Rijeka; University of Split-FESB, 21000 Split; University of Zagreb-FER, 10000 Zagreb; University of Osijek, 31000 Osijek; Rudjer Boskovic Institute, 10000 Zagreb, Croatia
| | - S M Colak
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - U Colin
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - E Colombo
- Instituto de Astrofísica de Canarias, E-38200 La Laguna, and Universidad de La Laguna, Departamento de Astrofísica, E-38206 La Laguna, Tenerife, Spain
| | - J L Contreras
- IPARCOS Institute and EMFTEL Department, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | - J Cortina
- Centro de Investigaciones Energticas, Medioambientales y Tecnolgicas, E-28040 Madrid, Spain
| | - S Covino
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - G D'Amico
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - V D'Elia
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - P Da Vela
- Università di Pisa, and INFN Pisa, I-56126 Pisa, Italy
| | - F Dazzi
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - A De Angelis
- Università di Padova and INFN, I-35131 Padova, Italy
| | - B De Lotto
- Università di Udine, and INFN Trieste, I-33100 Udine, Italy
| | - M Delfino
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - J Delgado
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - D Depaoli
- Istituto Nazionale Fisica Nucleare (INFN), 00044 Frascati (Roma) Italy
| | - F Di Pierro
- Istituto Nazionale Fisica Nucleare (INFN), 00044 Frascati (Roma) Italy
| | - L Di Venere
- Istituto Nazionale Fisica Nucleare (INFN), 00044 Frascati (Roma) Italy
| | - E Do Souto Espiñeira
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - D Dominis Prester
- Croatian Consortium: University of Rijeka, Department of Physics, 51000 Rijeka; University of Split-FESB, 21000 Split; University of Zagreb-FER, 10000 Zagreb; University of Osijek, 31000 Osijek; Rudjer Boskovic Institute, 10000 Zagreb, Croatia
| | - A Donini
- Università di Udine, and INFN Trieste, I-33100 Udine, Italy
| | - D Dorner
- Universität Würzburg, D-97074 Würzburg, Germany
| | - M Doro
- Università di Padova and INFN, I-35131 Padova, Italy
| | - D Elsaesser
- Technische Universität Dortmund, D-44221 Dortmund, Germany
| | - V Fallah Ramazani
- Finnish MAGIC Consortium: Finnish Centre of Astronomy with ESO (FINCA), University of Turku, FI-20014 Turku, Finland; Astronomy Research Unit, University of Oulu, FI-90014 Oulu, Finland
| | - A Fattorini
- Technische Universität Dortmund, D-44221 Dortmund, Germany
| | - G Ferrara
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - L Foffano
- Università di Padova and INFN, I-35131 Padova, Italy
| | - M V Fonseca
- IPARCOS Institute and EMFTEL Department, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | - L Font
- Departament de Física, and CERES-IEEC, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Spain
| | - C Fruck
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - S Fukami
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
| | - R J García López
- Instituto de Astrofísica de Canarias, E-38200 La Laguna, and Universidad de La Laguna, Departamento de Astrofísica, E-38206 La Laguna, Tenerife, Spain
| | - M Garczarczyk
- Deutsches Elektronen-Synchrotron (DESY), D-15738 Zeuthen, Germany
| | - S Gasparyan
- The Armenian Consortium: ICRANet-Armenia at NAS RA, A. Alikhanyan National Laboratory
| | - M Gaug
- Departament de Física, and CERES-IEEC, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Spain
| | - N Giglietto
- Istituto Nazionale Fisica Nucleare (INFN), 00044 Frascati (Roma) Italy
| | - F Giordano
- Istituto Nazionale Fisica Nucleare (INFN), 00044 Frascati (Roma) Italy
| | - P Gliwny
- University of Lodz, Faculty of Physics and Applied Informatics, Department of Astrophysics, 90-236 Lodz, Poland
| | - N Godinović
- Croatian Consortium: University of Rijeka, Department of Physics, 51000 Rijeka; University of Split-FESB, 21000 Split; University of Zagreb-FER, 10000 Zagreb; University of Osijek, 31000 Osijek; Rudjer Boskovic Institute, 10000 Zagreb, Croatia
| | - D Green
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - D Hadasch
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
| | - A Hahn
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - J Herrera
- Instituto de Astrofísica de Canarias, E-38200 La Laguna, and Universidad de La Laguna, Departamento de Astrofísica, E-38206 La Laguna, Tenerife, Spain
| | - J Hoang
- IPARCOS Institute and EMFTEL Department, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | - D Hrupec
- Croatian Consortium: University of Rijeka, Department of Physics, 51000 Rijeka; University of Split-FESB, 21000 Split; University of Zagreb-FER, 10000 Zagreb; University of Osijek, 31000 Osijek; Rudjer Boskovic Institute, 10000 Zagreb, Croatia
| | - M Hütten
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - T Inada
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
| | - S Inoue
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
| | - K Ishio
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - Y Iwamura
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
| | - L Jouvin
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - Y Kajiwara
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
| | - M Karjalainen
- Instituto de Astrofísica de Canarias, E-38200 La Laguna, and Universidad de La Laguna, Departamento de Astrofísica, E-38206 La Laguna, Tenerife, Spain
| | - D Kerszberg
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - Y Kobayashi
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
| | - H Kubo
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
| | - J Kushida
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
| | - A Lamastra
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - D Lelas
- Croatian Consortium: University of Rijeka, Department of Physics, 51000 Rijeka; University of Split-FESB, 21000 Split; University of Zagreb-FER, 10000 Zagreb; University of Osijek, 31000 Osijek; Rudjer Boskovic Institute, 10000 Zagreb, Croatia
| | - F Leone
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - E Lindfors
- Finnish MAGIC Consortium: Finnish Centre of Astronomy with ESO (FINCA), University of Turku, FI-20014 Turku, Finland; Astronomy Research Unit, University of Oulu, FI-90014 Oulu, Finland
| | - S Lombardi
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - F Longo
- Università di Udine, and INFN Trieste, I-33100 Udine, Italy
- Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, BG-1784 Sofia, Bulgaria
| | - M López
- IPARCOS Institute and EMFTEL Department, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | - R López-Coto
- Università di Padova and INFN, I-35131 Padova, Italy
| | - A López-Oramas
- Instituto de Astrofísica de Canarias, E-38200 La Laguna, and Universidad de La Laguna, Departamento de Astrofísica, E-38206 La Laguna, Tenerife, Spain
| | - S Loporchio
- Istituto Nazionale Fisica Nucleare (INFN), 00044 Frascati (Roma) Italy
| | | | - C Maggio
- Departament de Física, and CERES-IEEC, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Spain
| | - P Majumdar
- Saha Institute of Nuclear Physics, HBNI, 1/AF Bidhannagar, Salt Lake, Sector-1, Kolkata 700064, India
| | - M Makariev
- Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, BG-1784 Sofia, Bulgaria
| | - M Mallamaci
- Università di Padova and INFN, I-35131 Padova, Italy
| | - G Maneva
- Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, BG-1784 Sofia, Bulgaria
| | - M Manganaro
- Croatian Consortium: University of Rijeka, Department of Physics, 51000 Rijeka; University of Split-FESB, 21000 Split; University of Zagreb-FER, 10000 Zagreb; University of Osijek, 31000 Osijek; Rudjer Boskovic Institute, 10000 Zagreb, Croatia
| | - K Mannheim
- Universität Würzburg, D-97074 Würzburg, Germany
| | - L Maraschi
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - M Mariotti
- Università di Padova and INFN, I-35131 Padova, Italy
| | - M Martínez
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - D Mazin
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - S Mender
- Technische Universität Dortmund, D-44221 Dortmund, Germany
| | - S Mićanović
- Croatian Consortium: University of Rijeka, Department of Physics, 51000 Rijeka; University of Split-FESB, 21000 Split; University of Zagreb-FER, 10000 Zagreb; University of Osijek, 31000 Osijek; Rudjer Boskovic Institute, 10000 Zagreb, Croatia
| | - D Miceli
- Università di Udine, and INFN Trieste, I-33100 Udine, Italy
| | - T Miener
- IPARCOS Institute and EMFTEL Department, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | - M Minev
- Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, BG-1784 Sofia, Bulgaria
| | - J M Miranda
- Università di Siena and INFN Pisa, I-53100 Siena, Italy
| | - R Mirzoyan
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - E Molina
- Universitat de Barcelona, ICCUB, IEEC-UB, E-08028 Barcelona, Spain
| | - A Moralejo
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - D Morcuende
- IPARCOS Institute and EMFTEL Department, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | - V Moreno
- Departament de Física, and CERES-IEEC, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Spain
| | - E Moretti
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - P Munar-Adrover
- Departament de Física, and CERES-IEEC, Universitat Autònoma de Barcelona, E-08193 Bellaterra, Spain
| | - V Neustroev
- Finnish MAGIC Consortium: Finnish Centre of Astronomy with ESO (FINCA), University of Turku, FI-20014 Turku, Finland; Astronomy Research Unit, University of Oulu, FI-90014 Oulu, Finland
| | - C Nigro
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - K Nilsson
- Finnish MAGIC Consortium: Finnish Centre of Astronomy with ESO (FINCA), University of Turku, FI-20014 Turku, Finland; Astronomy Research Unit, University of Oulu, FI-90014 Oulu, Finland
| | - D Ninci
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - K Nishijima
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
| | - K Noda
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
| | - L Nogués
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - S Nozaki
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
| | - Y Ohtani
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
| | - T Oka
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
| | - J Otero-Santos
- Instituto de Astrofísica de Canarias, E-38200 La Laguna, and Universidad de La Laguna, Departamento de Astrofísica, E-38206 La Laguna, Tenerife, Spain
| | - M Palatiello
- Università di Udine, and INFN Trieste, I-33100 Udine, Italy
| | - D Paneque
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - R Paoletti
- Università di Siena and INFN Pisa, I-53100 Siena, Italy
| | - J M Paredes
- Universitat de Barcelona, ICCUB, IEEC-UB, E-08028 Barcelona, Spain
| | - L Pavletić
- Croatian Consortium: University of Rijeka, Department of Physics, 51000 Rijeka; University of Split-FESB, 21000 Split; University of Zagreb-FER, 10000 Zagreb; University of Osijek, 31000 Osijek; Rudjer Boskovic Institute, 10000 Zagreb, Croatia
| | - P Peñil
- IPARCOS Institute and EMFTEL Department, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | - C Perennes
- Università di Padova and INFN, I-35131 Padova, Italy
| | - M Peresano
- Università di Udine, and INFN Trieste, I-33100 Udine, Italy
| | - M Persic
- Università di Udine, and INFN Trieste, I-33100 Udine, Italy
| | | | - E Prandini
- Università di Padova and INFN, I-35131 Padova, Italy
| | - I Puljak
- Croatian Consortium: University of Rijeka, Department of Physics, 51000 Rijeka; University of Split-FESB, 21000 Split; University of Zagreb-FER, 10000 Zagreb; University of Osijek, 31000 Osijek; Rudjer Boskovic Institute, 10000 Zagreb, Croatia
| | - W Rhode
- Technische Universität Dortmund, D-44221 Dortmund, Germany
| | - M Ribó
- Universitat de Barcelona, ICCUB, IEEC-UB, E-08028 Barcelona, Spain
| | - J Rico
- Institut de Física d'Altes Energies (IFAE), The Barcelona Institute of Science and Technology (BIST), E-08193 Bellaterra (Barcelona), Spain
| | - C Righi
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - A Rugliancich
- Università di Pisa, and INFN Pisa, I-56126 Pisa, Italy
| | - L Saha
- IPARCOS Institute and EMFTEL Department, Universidad Complutense de Madrid, E-28040 Madrid, Spain
| | - N Sahakyan
- The Armenian Consortium: ICRANet-Armenia at NAS RA, A. Alikhanyan National Laboratory
| | - T Saito
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
| | - S Sakurai
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
| | - K Satalecka
- Deutsches Elektronen-Synchrotron (DESY), D-15738 Zeuthen, Germany
| | | | - K Schmidt
- Technische Universität Dortmund, D-44221 Dortmund, Germany
| | - T Schweizer
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - J Sitarek
- University of Lodz, Faculty of Physics and Applied Informatics, Department of Astrophysics, 90-236 Lodz, Poland
| | - I Šnidarić
- Croatian Consortium: University of Rijeka, Department of Physics, 51000 Rijeka; University of Split-FESB, 21000 Split; University of Zagreb-FER, 10000 Zagreb; University of Osijek, 31000 Osijek; Rudjer Boskovic Institute, 10000 Zagreb, Croatia
| | - D Sobczynska
- University of Lodz, Faculty of Physics and Applied Informatics, Department of Astrophysics, 90-236 Lodz, Poland
| | - A Spolon
- Università di Padova and INFN, I-35131 Padova, Italy
| | - A Stamerra
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - D Strom
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - M Strzys
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
| | - Y Suda
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - T Surić
- Croatian Consortium: University of Rijeka, Department of Physics, 51000 Rijeka; University of Split-FESB, 21000 Split; University of Zagreb-FER, 10000 Zagreb; University of Osijek, 31000 Osijek; Rudjer Boskovic Institute, 10000 Zagreb, Croatia
| | - M Takahashi
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
| | - F Tavecchio
- National Institute for Astrophysics (INAF), I-00136 Rome, Italy
| | - P Temnikov
- Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, BG-1784 Sofia, Bulgaria
| | - T Terzić
- Croatian Consortium: University of Rijeka, Department of Physics, 51000 Rijeka; University of Split-FESB, 21000 Split; University of Zagreb-FER, 10000 Zagreb; University of Osijek, 31000 Osijek; Rudjer Boskovic Institute, 10000 Zagreb, Croatia
| | - M Teshima
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - N Torres-Albà
- Universitat de Barcelona, ICCUB, IEEC-UB, E-08028 Barcelona, Spain
| | - L Tosti
- Istituto Nazionale Fisica Nucleare (INFN), 00044 Frascati (Roma) Italy
| | | | - G Vanzo
- Instituto de Astrofísica de Canarias, E-38200 La Laguna, and Universidad de La Laguna, Departamento de Astrofísica, E-38206 La Laguna, Tenerife, Spain
| | - M Vazquez Acosta
- Instituto de Astrofísica de Canarias, E-38200 La Laguna, and Universidad de La Laguna, Departamento de Astrofísica, E-38206 La Laguna, Tenerife, Spain
| | - S Ventura
- Università di Siena and INFN Pisa, I-53100 Siena, Italy
| | - V Verguilov
- Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, BG-1784 Sofia, Bulgaria
| | - C F Vigorito
- Istituto Nazionale Fisica Nucleare (INFN), 00044 Frascati (Roma) Italy
| | - V Vitale
- Istituto Nazionale Fisica Nucleare (INFN), 00044 Frascati (Roma) Italy
| | - I Vovk
- Japanese MAGIC Consortium: ICRR, The University of Tokyo, 277-8582 Chiba, Japan; Department of Physics, Kyoto University, 606-8502 Kyoto, Japan; Tokai University, 259-1292 Kanagawa, Japan; RIKEN, 351-0198 Saitama, Japan
| | - M Will
- Max-Planck-Institut für Physik, D-80805 München, Germany
| | - D Zarić
- Croatian Consortium: University of Rijeka, Department of Physics, 51000 Rijeka; University of Split-FESB, 21000 Split; University of Zagreb-FER, 10000 Zagreb; University of Osijek, 31000 Osijek; Rudjer Boskovic Institute, 10000 Zagreb, Croatia
| | - L Nava
- National Institute for Astrophysics (INAF), Osservatorio Astronomico di Brera, 23807 Merate, Italy
- Istituto Nazionale di Fisica Nucleare, Sezione di Trieste, 34149 Trieste, Italy
- Institute for Fundamental Physics of the Universe (IFPU), 34151 Trieste, Italy
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17
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Llandro J, Love DM, Kovács A, Caron J, Vyas KN, Kákay A, Salikhov R, Lenz K, Fassbender J, Scherer MRJ, Cimorra C, Steiner U, Barnes CHW, Dunin-Borkowski RE, Fukami S, Ohno H. Visualizing Magnetic Structure in 3D Nanoscale Ni-Fe Gyroid Networks. Nano Lett 2020; 20:3642-3650. [PMID: 32250635 DOI: 10.1021/acs.nanolett.0c00578] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Arrays of interacting 2D nanomagnets display unprecedented electromagnetic properties via collective effects, demonstrated in artificial spin ices and magnonic crystals. Progress toward 3D magnetic metamaterials is hampered by two challenges: fabricating 3D structures near intrinsic magnetic length scales (sub-100 nm) and visualizing their magnetic configurations. Here, we fabricate and measure nanoscale magnetic gyroids, periodic chiral networks comprising nanowire-like struts forming three-connected vertices. Via block copolymer templating, we produce Ni75Fe25 single-gyroid and double-gyroid (an inversion pair of single-gyroids) nanostructures with a 42 nm unit cell and 11 nm diameter struts, comparable to the exchange length in Ni-Fe. We visualize their magnetization distributions via off-axis electron holography with nanometer spatial resolution and interpret the patterns using finite-element micromagnetic simulations. Our results suggest an intricate, frustrated remanent state which is ferromagnetic but without a unique equilibrium configuration, opening new possibilities for collective phenomena in magnetism, including 3D magnonic crystals and unconventional computing.
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Affiliation(s)
- Justin Llandro
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - David M Love
- Cavendish Laboratory, University of Cambridge, J.J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - András Kovács
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Jan Caron
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Kunal N Vyas
- Cavendish Laboratory, University of Cambridge, J.J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Attila Kákay
- Helmholtz-Zentrum Dresden - Rossendorf (HZDR), Bautzner Landstrasse 400, 01328 Dresden, Germany
| | - Ruslan Salikhov
- Helmholtz-Zentrum Dresden - Rossendorf (HZDR), Bautzner Landstrasse 400, 01328 Dresden, Germany
| | - Kilian Lenz
- Helmholtz-Zentrum Dresden - Rossendorf (HZDR), Bautzner Landstrasse 400, 01328 Dresden, Germany
| | - Jürgen Fassbender
- Helmholtz-Zentrum Dresden - Rossendorf (HZDR), Bautzner Landstrasse 400, 01328 Dresden, Germany
- Technische Universität Dresden, Haeckelstrasse 3, 01069 Dresden, Germany
| | - Maik R J Scherer
- Cavendish Laboratory, University of Cambridge, J.J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Christian Cimorra
- Cavendish Laboratory, University of Cambridge, J.J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Ullrich Steiner
- Adolphe Merkle Institute, Chemin des Verdiers 4, 1700 Fribourg, Switzerland
| | - Crispin H W Barnes
- Cavendish Laboratory, University of Cambridge, J.J. Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Rafal E Dunin-Borkowski
- Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons and Peter Grünberg Institute, Forschungszentrum Jülich, 52425 Jülich, Germany
| | - Shunsuke Fukami
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845 Japan
- WPI Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Hideo Ohno
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Science and Innovation in Spintronics, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845 Japan
- WPI Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
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18
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Grollier J, Querlioz D, Camsari KY, Everschor-Sitte K, Fukami S, Stiles MD. Neuromorphic Spintronics. Nat Electron 2020; 3:10.1038/s41928-019-0360-9. [PMID: 33367204 PMCID: PMC7754689 DOI: 10.1038/s41928-019-0360-9] [Citation(s) in RCA: 151] [Impact Index Per Article: 37.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Accepted: 12/18/2019] [Indexed: 05/06/2023]
Abstract
Neuromorphic computing uses basic principles inspired by the brain to design circuits that perform artificial intelligence tasks with superior energy efficiency. Traditional approaches have been limited by the energy area of artificial neurons and synapses realized with conventional electronic devices. In recent years, multiple groups have demonstrated that spintronic nanodevices, which exploit the magnetic as well as electrical properties of electrons, can increase the energy efficiency and decrease the area of these circuits. Among the variety of spintronic devices that have been used, magnetic tunnel junctions play a prominent role because of their established compatibility with standard integrated circuits and their multifunctionality. Magnetic tunnel junctions can serve as synapses, storing connection weights, functioning as local, nonvolatile digital memory or as continuously varying resistances. As nano-oscillators, they can serve as neurons, emulating the oscillatory behavior of sets of biological neurons. As superparamagnets, they can do so by emulating the random spiking of biological neurons. Magnetic textures like domain walls or skyrmions can be configured to function as neurons through their non-linear dynamics. Several implementations of neuromorphic computing with spintronic devices demonstrate their promise in this context. Used as variable resistance synapses, magnetic tunnel junctions perform pattern recognition in an associative memory. As oscillators, they perform spoken digit recognition in reservoir computing and when coupled together, classification of signals. As superparamagnets, they perform population coding and probabilistic computing. Simulations demonstrate that arrays of nanomagnets and films of skyrmions can operate as components of neuromorphic computers. While these examples show the unique promise of spintronics in this field, there are several challenges to scaling up, including the efficiency of coupling between devices and the relatively low ratio of maximum to minimum resistances in the individual devices.
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Affiliation(s)
- J. Grollier
- Unité Mixte de Physique CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, 91767 Palaiseau, France
| | - D. Querlioz
- Centre de Nanosciences et de Nanotechnologies, Univ. Paris-Sud, CNRS, Université Paris-Saclay, 91405 Orsay, France
| | - K. Y. Camsari
- School of Electrical & Computer Engineering, Purdue University, West Lafayette, Indiana 47907 USA
| | - K. Everschor-Sitte
- Institute of Physics, Johannes Gutenberg University Mainz, D-55099 Mainz, Germany
| | - S. Fukami
- Research Institute of Electrical Communication, Tohoku University, Sendai, Miyagi 9808577, Japan
| | - M. D. Stiles
- National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
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19
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Kurenkov A, DuttaGupta S, Zhang C, Fukami S, Horio Y, Ohno H. Artificial Neuron and Synapse Realized in an Antiferromagnet/Ferromagnet Heterostructure Using Dynamics of Spin-Orbit Torque Switching. Adv Mater 2019; 31:e1900636. [PMID: 30989740 DOI: 10.1002/adma.201900636] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Revised: 03/25/2019] [Indexed: 06/09/2023]
Abstract
Efficient information processing in the human brain is achieved by dynamics of neurons and synapses, motivating effective implementation of artificial spiking neural networks. Here, the dynamics of spin-orbit torque switching in antiferromagnet/ferromagnet heterostructures is studied to show the capability of the material system to form artificial neurons and synapses for asynchronous spiking neural networks. The magnetization switching, driven by a single current pulse or trains of pulses, is examined as a function of the pulse width (1 s to 1 ns), amplitude, number, and pulse-to-pulse interval. Based on this dynamics and the unique ability of the system to exhibit binary or analog behavior depending on the device size, key functionalities of a synapse (spike-timing-dependent plasticity) and a neuron (leaky integrate-and-fire) are reproduced in the same material and on the basis of the same working principle. These results open a way toward spintronics-based neuromorphic hardware that executes cognitive tasks with the efficiency of the human brain.
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Affiliation(s)
- Aleksandr Kurenkov
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- Center for Science and Innovation in Spintronics (Core Research Cluster), Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
| | - Samik DuttaGupta
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- Center for Science and Innovation in Spintronics (Core Research Cluster), Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- Center for Spintronics Integrated Systems, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
| | - Chaoliang Zhang
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- Center for Spintronics Integrated Systems, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, 6-3 Aramaki Aza Aoba, Aoba-ku, Sendai, 980-8578, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, 980-0845, Japan
| | - Shunsuke Fukami
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- Center for Science and Innovation in Spintronics (Core Research Cluster), Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- Center for Spintronics Integrated Systems, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, 980-0845, Japan
- WPI Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
| | - Yoshihiko Horio
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
| | - Hideo Ohno
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- Center for Science and Innovation in Spintronics (Core Research Cluster), Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- Center for Spintronics Integrated Systems, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai, 980-0845, Japan
- WPI Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577, Japan
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20
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Bean JJ, Saito M, Fukami S, Sato H, Ikeda S, Ohno H, Ikuhara Y, McKenna KP. Atomic structure and electronic properties of MgO grain boundaries in tunnelling magnetoresistive devices. Sci Rep 2017; 7:45594. [PMID: 28374755 PMCID: PMC5379487 DOI: 10.1038/srep45594] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 02/27/2017] [Indexed: 11/11/2022] Open
Abstract
Polycrystalline metal oxides find diverse applications in areas such as nanoelectronics, photovoltaics and catalysis. Although grain boundary defects are ubiquitous their structure and electronic properties are very poorly understood since it is extremely challenging to probe the structure of buried interfaces directly. In this paper we combine novel plan-view high-resolution transmission electron microscopy and first principles calculations to provide atomic level understanding of the structure and properties of grain boundaries in the barrier layer of a magnetic tunnel junction. We show that the highly [001] textured MgO films contain numerous tilt grain boundaries. First principles calculations reveal how these grain boundaries are associated with locally reduced band gaps (by up to 3 eV). Using a simple model we show how shunting a proportion of the tunnelling current through grain boundaries imposes limits on the maximum magnetoresistance that can be achieved in devices.
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Affiliation(s)
- Jonathan J. Bean
- Department of Physics, University of York, Heslington, York, North Yorkshire, YO10 5DD,UK
| | - Mitsuhiro Saito
- Institute of Engineering Innovation, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-8656, Japan
- Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Shunsuke Fukami
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Spintronics Integrated Systems, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845, Japan
- Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Hideo Sato
- Center for Spintronics Integrated Systems, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845, Japan
- Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Shoji Ikeda
- Center for Spintronics Integrated Systems, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845, Japan
- Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Hideo Ohno
- Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Spintronics Integrated Systems, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845, Japan
- Center for Spintronics Research Network, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Yuichi Ikuhara
- Institute of Engineering Innovation, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-8656, Japan
- Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Keith P. McKenna
- Department of Physics, University of York, Heslington, York, North Yorkshire, YO10 5DD,UK
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21
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Fukami S, Anekawa T, Zhang C, Ohno H. A spin-orbit torque switching scheme with collinear magnetic easy axis and current configuration. Nat Nanotechnol 2016; 11:621-625. [PMID: 26999481 DOI: 10.1038/nnano.2016.29] [Citation(s) in RCA: 77] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 02/10/2016] [Indexed: 06/05/2023]
Abstract
Spin-orbit torque, a torque brought about by in-plane current via the spin-orbit interactions in heavy-metal/ferromagnet nanostructures, provides a new pathway to switch the magnetization direction. Although there are many recent studies, they all build on one of two structures that have the easy axis of a nanomagnet lying orthogonal to the current, that is, along the z or y axes. Here, we present a new structure with the third geometry, that is, with the easy axis collinear with the current (along the x axis). We fabricate a three-terminal device with a Ta/CoFeB/MgO-based stack and demonstrate the switching operation driven by the spin-orbit torque due to Ta with a negative spin Hall angle. Comparisons with different geometries highlight the previously unknown mechanisms of spin-orbit torque switching. Our work offers a new avenue for exploring the physics of spin-orbit torque switching and its application to spintronics devices.
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Affiliation(s)
- S Fukami
- Center for Spintronics Integrated Systems, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aoba, Aramaki, Aoba, Sendai 980-0845, Japan
| | - T Anekawa
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan
| | - C Zhang
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan
| | - H Ohno
- Center for Spintronics Integrated Systems, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aoba, Aramaki, Aoba, Sendai 980-0845, Japan
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980-8577, Japan
- WPI Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba, Sendai 980 8577, Japan
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22
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Fukami S, Zhang C, DuttaGupta S, Kurenkov A, Ohno H. Magnetization switching by spin-orbit torque in an antiferromagnet-ferromagnet bilayer system. Nat Mater 2016; 15:535-541. [PMID: 26878314 DOI: 10.1038/nmat4566] [Citation(s) in RCA: 176] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 01/08/2016] [Indexed: 06/05/2023]
Abstract
Spin-orbit torque (SOT)-induced magnetization switching shows promise for realizing ultrafast and reliable spintronics devices. Bipolar switching of the perpendicular magnetization by the SOT is achieved under an in-plane magnetic field collinear with an applied current. Typical structures studied so far comprise a nonmagnet/ferromagnet (NM/FM) bilayer, where the spin Hall effect in the NM is responsible for the switching. Here we show that an antiferromagnet/ferromagnet (AFM/FM) bilayer system also exhibits a SOT large enough to switch the magnetization of the FM. In this material system, thanks to the exchange bias of the AFM, we observe the switching in the absence of an applied field by using an antiferromagnetic PtMn and ferromagnetic Co/Ni multilayer with a perpendicular easy axis. Furthermore, tailoring the stack achieves a memristor-like behaviour where a portion of the reversed magnetization can be controlled in an analogue manner. The AFM/FM system is thus a promising building block for SOT devices as well as providing an attractive pathway towards neuromorphic computing.
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Affiliation(s)
- Shunsuke Fukami
- Center for Spintronics Integrated Systems, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845, Japan
| | - Chaoliang Zhang
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Samik DuttaGupta
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Aleksandr Kurenkov
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Hideo Ohno
- Center for Spintronics Integrated Systems, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University, 468-1 Aramaki Aza Aoba, Aoba-ku, Sendai 980-0845, Japan
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- WPI Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
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23
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Wang Z, Saito M, McKenna KP, Fukami S, Sato H, Ikeda S, Ohno H, Ikuhara Y. Atomic-Scale Structure and Local Chemistry of CoFeB-MgO Magnetic Tunnel Junctions. Nano Lett 2016; 16:1530-1536. [PMID: 26905782 DOI: 10.1021/acs.nanolett.5b03627] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Magnetic tunnel junctions (MTJs) constitute a promising building block for future nonvolatile memories and logic circuits. Despite their pivotal role, spatially resolving and chemically identifying each individual stacking layer remains challenging due to spatially localized features that complicate characterizations limiting understanding of the physics of MTJs. Here, we combine advanced electron microscopy, spectroscopy, and first-principles calculations to obtain a direct structural and chemical imaging of the atomically confined layers in a CoFeB-MgO MTJ, and clarify atom diffusion and interface structures in the MTJ following annealing. The combined techniques demonstrate that B diffuses out of CoFeB electrodes into Ta interstitial sites rather than MgO after annealing, and CoFe bonds atomically to MgO grains with an epitaxial orientation relationship by forming Fe(Co)-O bonds, yet without incorporation of CoFe in MgO. These findings afford a comprehensive perspective on structure and chemistry of MTJs, helping to develop high-performance spintronic devices by atomistic design.
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Affiliation(s)
- Zhongchang Wang
- WPI Advanced Institute for Materials Research, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Mitsuhiro Saito
- WPI Advanced Institute for Materials Research, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Institute of Engineering Innovation, University of Tokyo , 2-11-16, Yayoi, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Keith P McKenna
- WPI Advanced Institute for Materials Research, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Department of Physics, University of York , Heslington, York YO10 5DD, United Kingdom
| | - Shunsuke Fukami
- Center for Spintronics Integrated Systems, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University , 468-1 Aramaki, Aza, Aoba-ku, Sendai 980-8577, Japan
| | - Hideo Sato
- Center for Spintronics Integrated Systems, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University , 468-1 Aramaki, Aza, Aoba-ku, Sendai 980-8577, Japan
| | - Shoji Ikeda
- Center for Spintronics Integrated Systems, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University , 468-1 Aramaki, Aza, Aoba-ku, Sendai 980-8577, Japan
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Hideo Ohno
- WPI Advanced Institute for Materials Research, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Spintronics Integrated Systems, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Center for Innovative Integrated Electronic Systems, Tohoku University , 468-1 Aramaki, Aza, Aoba-ku, Sendai 980-8577, Japan
- Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Yuichi Ikuhara
- WPI Advanced Institute for Materials Research, Tohoku University , 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
- Institute of Engineering Innovation, University of Tokyo , 2-11-16, Yayoi, Bunkyo-ku, Tokyo 113-8656, Japan
- Nanostructures Research Laboratory, Japan Fine Ceramics Center , 2-4-1 Mutsuno, Atsuta, Nagoya 456-8587, Japan
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24
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Suzuki D, Natsui M, Mochizuki A, Miura S, Honjo H, Kinoshita K, Fukami S, Sato H, Ikeda S, Endoh T, Ohno H, Hanyu T. Design and fabrication of a perpendicular magnetic tunnel junction based nonvolatile programmable switch achieving 40% less area using shared-control transistor structure. J Appl Phys 2014; 115:17B742. [PMID: 24753634 PMCID: PMC3977752 DOI: 10.1063/1.4868332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Accepted: 12/12/2013] [Indexed: 06/03/2023]
Abstract
A compact nonvolatile programmable switch (NVPS) using 90 nm CMOS technology together with perpendicular magnetic tunnel junction (p-MTJ) devices is fabricated for zero-standby-power field-programmable gate array. Because routing information does not change once it is programmed into an NVPS, high-speed read and write accesses are not required and a write-control transistor can be shared among all the NVPSs, which greatly simplifies structure of the NVPS. In fact, the effective area of the proposed NVPS is reduced by 40% compared to that of a conventional MTJ-based NVPS. The instant on/off behavior without external nonvolatile memory access is also demonstrated using the fabricated test chip.
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Fukami S, Yamanouchi M, Ikeda S, Ohno H. Depinning probability of a magnetic domain wall in nanowires by spin-polarized currents. Nat Commun 2014; 4:2293. [PMID: 23945735 DOI: 10.1038/ncomms3293] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2013] [Accepted: 07/11/2013] [Indexed: 11/09/2022] Open
Abstract
Current-induced magnetic domain wall motion is attractive for manipulating magnetization direction in spintronics devices, which open a new era of electronics. Up to now, in spite of a crucial significance to applications, investigation on a current-induced domain wall depinning probability, especially in sub-nano to a-few-nanosecond range has been lacking. Here we report on the probability of the depinning in perpendicularly magnetized Co/Ni nanowires in this timescale. A high depinning probability was obtained even for 2-ns pulses with a current density of less than 10¹² A m⁻². A one-dimensional Landau-Lifshitz-Gilbert calculation taking into account thermal fluctuations reproduces well the experimental results. We also calculate the depinning probability as functions of various parameters and found that parameters other than the coercive field do not affect the transition width of the probability. These findings will allow one to design high-speed and reliable magnetic devices based on the domain wall motion.
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Affiliation(s)
- S Fukami
- Center for Spintronics Integrated Systems, Tohoku University, Sendai 980-8577, Japan
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26
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Kim J, Sinha J, Hayashi M, Yamanouchi M, Fukami S, Suzuki T, Mitani S, Ohno H. Layer thickness dependence of the current-induced effective field vector in Ta|CoFeB|MgO. Nat Mater 2013; 12:240-5. [PMID: 23263641 DOI: 10.1038/nmat3522] [Citation(s) in RCA: 167] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2012] [Accepted: 11/13/2012] [Indexed: 05/17/2023]
Abstract
Current-induced effective magnetic fields can provide efficient ways of electrically manipulating the magnetization of ultrathin magnetic heterostructures. Two effects, known as the Rashba spin orbit field and the spin Hall spin torque, have been reported to be responsible for the generation of the effective field. However, a quantitative understanding of the effective field, including its direction with respect to the current flow, is lacking. Here we describe vector measurements of the current-induced effective field in Ta|CoFeB|MgO heterostructrures. The effective field exhibits a significant dependence on the Ta and CoFeB layer thicknesses. In particular, a 1 nm thickness variation of the Ta layer can change the magnitude of the effective field by nearly two orders of magnitude. Moreover, its sign changes when the Ta layer thickness is reduced, indicating that there are two competing effects contributing to it. Our results illustrate that the presence of atomically thin metals can profoundly change the landscape for controlling magnetic moments in magnetic heterostructures electrically.
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Affiliation(s)
- Junyeon Kim
- National Institute for Materials Science, Tsukuba 305-0047, Japan
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27
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Koyama T, Ueda K, Kim KJ, Yoshimura Y, Chiba D, Yamada K, Jamet JP, Mougin A, Thiaville A, Mizukami S, Fukami S, Ishiwata N, Nakatani Y, Kohno H, Kobayashi K, Ono T. Current-induced magnetic domain wall motion below intrinsic threshold triggered by Walker breakdown. Nat Nanotechnol 2012; 7:635-639. [PMID: 22961306 DOI: 10.1038/nnano.2012.151] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2012] [Accepted: 08/06/2012] [Indexed: 06/01/2023]
Abstract
Controlling the position of a magnetic domain wall with electric current may allow for new types of non-volatile memory and logic devices. To be practical, however, the threshold current density necessary for domain wall motion must be reduced below present values. Intrinsic pinning due to magnetic anisotropy, as recently observed in perpendicularly magnetized Co/Ni nanowires, has been shown to give rise to an intrinsic current threshold J(th)(0). Here, we show that domain wall motion can be induced at current densities 40% below J(th)(0) when an external magnetic field of the order of the domain wall pinning field is applied. We observe that the velocity of the domain wall motion is the vector sum of current- and field-induced velocities, and that the domain wall can be driven against the direction of a magnetic field as large as 2,000 Oe, even at currents below J(th)(0). We show that this counterintuitive phenomenon is triggered by Walker breakdown, and that the additive velocities provide a unique way of simultaneously determining the spin polarization of current and the Gilbert damping constant.
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Affiliation(s)
- T Koyama
- Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan
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28
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Hayashi M, Nakatani Y, Fukami S, Yamanouchi M, Mitani S, Ohno H. Domain wall dynamics driven by spin transfer torque and the spin-orbit field. J Phys Condens Matter 2012; 24:024221. [PMID: 22172940 DOI: 10.1088/0953-8984/24/2/024221] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We have studied current-driven dynamics of domain walls when an in-plane magnetic field is present in perpendicularly magnetized nanowires using an analytical model and micromagnetic simulations. We model an experimentally studied system, ultrathin magnetic nanowires with perpendicular anisotropy, where an effective in-plane magnetic field is developed when current is passed along the nanowire due to the Rashba-like spin-orbit coupling. Using a one-dimensional model of a domain wall together with micromagnetic simulations, we show that the existence of such in-plane magnetic fields can either lower or raise the threshold current needed to cause domain wall motion. In the presence of the in-plane field, the threshold current differs for positive and negative currents for a given wall chirality, and the wall motion becomes sensitive to out-of-plane magnetic fields. We show that large non-adiabatic spin torque can counteract the effect of the in-plane field.
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29
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Chiba D, Fukami S, Shimamura K, Ishiwata N, Kobayashi K, Ono T. Electrical control of the ferromagnetic phase transition in cobalt at room temperature. Nat Mater 2011; 10:853-856. [PMID: 22020007 DOI: 10.1038/nmat3130] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2011] [Accepted: 08/31/2011] [Indexed: 05/31/2023]
Abstract
Electrical control of magnetic properties is crucial for device applications in the field of spintronics. Although the magnetic coercivity or anisotropy has been successfully controlled electrically in metals as well as in semiconductors, the electrical control of Curie temperature has been realized only in semiconductors at low temperature. Here, we demonstrate the room-temperature electrical control of the ferromagnetic phase transition in cobalt, one of the most representative transition-metal ferromagnets. Solid-state field effect devices consisting of a ultrathin cobalt film covered by a dielectric layer and a gate electrode were fabricated. We prove that the Curie temperature of cobalt can be changed by up to 12 K by applying a gate electric field of about ±2 MV cm(-1). The two-dimensionality of the cobalt film may be relevant to our observations. The demonstrated electric field effect in the ferromagnetic metal at room temperature is a significant step towards realizing future low-power magnetic applications.
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30
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Koyama T, Chiba D, Ueda K, Kondou K, Tanigawa H, Fukami S, Suzuki T, Ohshima N, Ishiwata N, Nakatani Y, Kobayashi K, Ono T. Observation of the intrinsic pinning of a magnetic domain wall in a ferromagnetic nanowire. Nat Mater 2011; 10:194-197. [PMID: 21336264 DOI: 10.1038/nmat2961] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2010] [Accepted: 01/13/2011] [Indexed: 05/30/2023]
Abstract
The spin transfer torque is essential for electrical magnetization switching. When a magnetic domain wall is driven by an electric current through an adiabatic spin torque, the theory predicts a threshold current even for a perfect wire without any extrinsic pinning. The experimental confirmation of this 'intrinsic pinning', however, has long been missing. Here, we give evidence that this intrinsic pinning determines the threshold, and thus that the adiabatic spin torque dominates the domain wall motion in a perpendicularly magnetized Co/Ni nanowire. The intrinsic nature manifests itself both in the field-independent threshold current and in the presence of its minimum on tuning the wire width. The demonstrated domain wall motion purely due to the adiabatic spin torque will serve to achieve robust operation and low energy consumption in spintronic devices.
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31
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Tabuchi T, Ohashi H, Fukami S, Susaki N, Kunishima S, Yokozawa T, Nagai H, Moritani S, Ichihara S, Saito H, Hamaguchi M. A case of myelofibrosis with myeloid metaplasia with JAK2(V617F) mutation who developed fibrous tumours in multiple organs. Eur J Haematol 2006; 77:264-6. [PMID: 16923114 DOI: 10.1111/j.1600-0609.2006.00695.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Murase K, Mukai W, Fukami S, Matsumoto K, Yang Z. Performance of model observers for lesion detection in SPECT imaging. Igaku Butsuri 2006; 26:108-17. [PMID: 17344642] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Received: 06/15/2006] [Accepted: 11/16/2006] [Indexed: 05/14/2023]
Abstract
UNLABELLED We investigated the performance of model observers (the channelized Hotelling observer (CHO), channelized non-prewhitening observer (CNPWO) and non-prewhitening observer (NPWO)) for lesion detection in single photon emission computed tomography (SPECT) imaging. METHODS Using a simulation tool, we generated the numerical phantom with a hot lesion for cases having various contrasts and sizes and projection data including photon attenuation, scatter and distance-dependent collimator-detector response. The SPECT images were reconstructed using the filtered back-projection method and the ordered-subsets expectation-maximization method. Fifty lesion-absent and lesion-present images were generated and the detectability indices derived from CHO (d(CHO)), CNPWO (d(CNPWO)) and NPWO (d(NPWO)) were calculated from a total of 100 images. These procedures were repeated 5 times for each condition. The relationships among these detectability indices were investigated for various projection counts, lesion contrasts and lesion sizes. RESULTS All detectability indices increased with increases of projection count, lesion contrast and lesion size. Although there were good correlations among them, the relationships between d(CHO) and d(NPWO) and between d(CNPWO) and d(NPWO) were not linear. The coefficient of variation of d(CHO) tended to be significantly greater than that of d(CNPWO) and d(NPWO). CONCLUSION This study will be useful for understanding the performance of model observers when evaluating lesion detection in SPECT imaging.
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Affiliation(s)
- Kenya Murase
- Department of Medical Physics and Engineering, Division of Medical Technology and Science, Course of Health Science, Graduate School of Medicine, Osaka University, 1-7 Yamadaoka, Suita-shi, Osaka, 565-0871, Japan.
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Naito S, Fukami S, Mizokami Y, Ishida N, Takano H, Koizumi M, Kano H. Effect of Freeze-Thaw Cycles on the Gluten Fibrils and Crumb Grain Structures of Breads Made from Frozen Doughs. Cereal Chem 2004. [DOI: 10.1094/cchem.2004.81.1.80] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- S. Naito
- National Food Research Institute, Tsukuba Science City, Ibaraki 305-8642, Japan
- Corresponding author. Phone: +81-29-838-8057. Fax: +81-29-838-7996. E-mail:
| | - S. Fukami
- Tsukishima Foods Industry Co., Ltd., 3-17-9, Higashikasai, Edogawa-ku, Tokyo 134-8520, Japan
| | - Y. Mizokami
- Tsukishima Foods Industry Co., Ltd., 3-17-9, Higashikasai, Edogawa-ku, Tokyo 134-8520, Japan
| | - N. Ishida
- National Food Research Institute, Tsukuba Science City, Ibaraki 305-8642, Japan
| | - H. Takano
- Agriculture, Forestry and Fisheries Technical Information Society, Seifun-kaikan 6F, 15-6, Kabuto-cho, Nihonbashi, Chuo-ku, Tokyo 103-0026, Japan
| | - M. Koizumi
- National Food Research Institute, Tsukuba Science City, Ibaraki 305-8642, Japan
| | - H. Kano
- National Institute of Agrobiological Sciences, Tsukuba Science City, Ibaraki 305-8602, Japan
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Inoue H, Cho JY, Satodate H, Sakashita M, Hidaka E, Fukami S, Kazawa T, Yoshida T, Shiokawa A, Kudo S. Development of virtual histology and virtual biopsy using laser-scanning confocal microscopy. Scand J Gastroenterol 2003:37-9. [PMID: 12797680 DOI: 10.1080/00855910310001485] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
The aim of this project is to acquire a direct image of histology from in vivo gastrointestinal mucosa. In other words, the task of 'endo-microscope' is to observe the cellular architecture of tissue in vivo during routine endoscopic examination. As the first step to completing this study, resected fresh specimens from the oesophagus. stomach and colon were examined by laser-scanning confocal microscopy (LCM) (Fluoview, Olympus, Tokyo). Fresh untreated mucosal specimens obtained by endoscopic pinch biopsy, polypectomy or endoscopic mucosal resection were collected and placed in normal saline and examined by LCM, collecting the reflective light of a 488-nm wavelength argon laser beam. As the second step, a probe-type LCM 'endo-microscope' was designed and applied to observe the human oral-cavity mucosa. The probe has 4.5-mm outer diameter and 20-cm length, which enables easy access to oral cavity mucosa. The estimated special resolution of the probe is 1-5 microm. A real-time microscopic image directly from ex vivo fresh specimens was acquired. The acquired LCM images corresponded well with the conventional H-E light microscopic images. Cell wall, nucleus and cytoplasm were simultaneously visualized by LCM scanning. This novel method enables serial imaginary microscopic sections on fresh specimens. In addition, a probe-type LCM 'endo-microscope' was designed and was applied to observe human oral cavity mucosa. Virtual histological images from the living oral squamous cell were successfully obtained. LCM images from ex vivo fresh specimens demonstrated the features of the H-E staining histological image. In the next step to accomplish our project, we developed a LCM probe with 4.5-mm outer diameter to obtain a virtual image of human oral cavity mucosa.
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Affiliation(s)
- H Inoue
- Digestive Disease Center, Dept. of Pathology, Showa University Northern Yokohama Hospital, Yokohama, Japan
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35
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Sugimoto M, Uchida I, Fukami S, Takenoshita M, Mashimo T, Yoshiya I. The alpha and gamma subunit-dependent effects of local anesthetics on recombinant GABA(A) receptors. Eur J Pharmacol 2000; 401:329-37. [PMID: 10936490 DOI: 10.1016/s0014-2999(00)00463-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Although convulsions due to local anesthetic systemic toxicity are thought to be due to inhibition of GABA(A) receptor-linked currents in the central nervous system, the mechanism of action remains unclear. We therefore examined the effects of local anesthetics on gamma-aminobutyric acid (GABA)-induced currents using recombinant GABA(A) receptors with specific combinations of subunits. Murine GABA(A) receptors were expressed by injection of cRNAs encoding each subunit into Xenopus oocytes. The effects of local anesthetics (lidocaine, bupivacaine, procaine and tetracaine) on GABA-induced currents of receptors expressing different subunit combinations (alpha1beta2, alpha1beta2gamma2s, alpha4beta2gamma2s and beta2) were examined via the two electrode voltage clamp method. At alpha1beta2, alpha1beta2gamma2s and alpha4beta2gamma2s GABA(A) receptors, all local anesthetics inhibited GABA-induced currents in a dose-dependent manner. The presence of the gamma2s subunit resulted in a greater inhibition by all local anesthetics, but the presence of the alpha4 subunit resulted in less inhibition. At beta2 homomeric receptors, local anesthetics directly induced an outward current similar to that of picrotoxin. These data indicated that (1) the alpha and gamma subunits of GABA(A) receptors modulated the inhibitory effects of local anesthetics on GABA(A) function, and (2) local anesthetics can activate the beta2 subunit and may block the GABA(A) receptor channel pore.
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MESH Headings
- Anesthetics, Local/pharmacology
- Animals
- Bupivacaine/pharmacology
- DNA, Recombinant/drug effects
- DNA, Recombinant/genetics
- DNA, Recombinant/physiology
- Dose-Response Relationship, Drug
- Hydrogen-Ion Concentration
- Lidocaine/pharmacology
- Membrane Potentials/drug effects
- Mice
- Oocytes/drug effects
- Oocytes/physiology
- Picrotoxin/pharmacology
- Procaine/pharmacology
- RNA, Complementary/administration & dosage
- RNA, Complementary/genetics
- Receptors, GABA-A/drug effects
- Receptors, GABA-A/genetics
- Receptors, GABA-A/physiology
- Tetracaine/pharmacology
- Xenopus laevis
- gamma-Aminobutyric Acid/pharmacology
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Affiliation(s)
- M Sugimoto
- Department of Anesthesiology, Osaka University Medical School, 2-2, Yamadao-ka, Suita, 565-0871, Osaka, Japan.
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36
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Fukami S, Uchida I, Takenoshita M, Mashimo T, Yoshiya I. The effects of a point mutation of the beta2 subunit of GABA(A) receptor on direct and modulatory actions of general anesthetics. Eur J Pharmacol 1999; 368:269-76. [PMID: 10193664 DOI: 10.1016/s0014-2999(99)00033-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The gamma-aminobutyric acid type A receptor (GABA(A) receptor) sites involved in the direct and modulatory actions of general anesthetics remain to be elucidated. The mutation of tyrosine at position 157 in the beta2 GABA(A) receptor subunit was reported to reduce sensitivity to activation by GABA, but not pentobarbital. We examined whether this mutation of the beta2 subunit (Tyr157-->Phe) affects the direct and modulatory actions of other general anesthetics such as propofol and etomidate. Using the two-electrode voltage clamp method, we recorded Cl- current in Xenopus oocytes expressing alpha1beta2gamma2s and alpha1-mutated beta2gamma2s subunits. The mutation of the beta2 subunit reduced the apparent affinity for propofol. However, the mutation had no effect on both the direct actions of pentobarbital and etomidate or on the modulatory actions of pentobarbital, propofol and etomidate. These results suggest that unique loci may exist for the direct action of propofol and that the GABA binding site may not mediate the modulatory actions of general anesthetics at GABA(A) receptors.
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Affiliation(s)
- S Fukami
- Department of Anesthesiology, Osaka University Medical School, Suita, Japan
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Abstract
The effect of nitric oxide (NO) on GABA induced Cl- current of recombinant GABAA receptors was studied. Either alpha 1 beta 2 gamma 2s or alpha 1 beta 2 subunit mRNAs synthesized from cDNA of mouse brain were injected into Xenopus oocytes and functional GABAA receptors were expressed. GABA-induced Cl- current was measured with the two electrode voltage clamp technique. The NO donor NOC-18 reduced the GABA-induced Cl- current in the alpha 1 beta 2 gamma 2s subunit receptor in a dose-dependent manner. In alpha 1,beta 2 subunit receptor, NOC-18 had no effects on GABA-induced currents at low concentrations but showed potentiation at high concentration. These effects were antagonized by the NO extinguisher, carboxy-PTIO. The cGMP analogue 8-Br-cGMP failed to induce NO-like effects. NO directly acts at the GABAA receptor and the gamma 2s subunit is involved in its action.
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Affiliation(s)
- S Fukami
- Department of Anesthesiology, Osaka University Medical School, Japan
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Abstract
A Japanese boy with Kabuki make-up syndrome associated with West syndrome is reported. He developed periodic tonic spasms at 6 months of age while his electro-encephalogram also revealed hypsarrhythmia. Although only a few previously reported cases of Kabuki make-up syndrome have been associated with epilepsy, it is likely that epileptic seizures are another primary feature of Kabuki make-up syndrome.
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Affiliation(s)
- A Mitsudome
- Department of Pediatrics, School of Medicine, Fukuoka University, Japan
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39
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Kinouchi K, Fukumitsu K, Yanagi K, Fukami S, Matsuyama M, Hiramatsu K, Takeuchi M, Miyamoto Y, Kitamura S. [HELP syndrome and anesthetic management]. Masui 1996; 45:617-23. [PMID: 8847789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
From January 1990 to December 1994, 24 parturients were diagnosed as having HELLP syndrome alone or combined with preeclampsia/eclampsia among 8,224 patients who were delivered at our institution. They consisted of 14 primiparous and 10 multiparous patients. Mean maternal age was 28.9 +/- 3.3 and gestational age was 34.8 +/- 5.6 weeks. Of 24 parturients, 8 had vaginal delivery and the remaining 16 were delivered by caesarean section. Serious maternal morbidity included eclampsia (n = 3), preeclampsia (n = 18), renal failure (n = 5), hydrothorax (n = 4), and DIC (n = 1). There was no maternal death. There were 3 intrauterine fetal deaths and two neonatal deaths. Perinatal deaths were 2 (0.9%, 2/26). Three caesarean sections were performed under general anesthesia, and 13 under spinal anesthesia. In cases with apparent bleeding tendency, spinal and epidural anesthesia should be avoided. In providing general anesthesia, hypertension should be controlled, and the uterus is preferably dilated before the delivery and contracted there-after.
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Affiliation(s)
- K Kinouchi
- Department of Anesthesiology, Osaka Medical Center, Japan
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40
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Yoshida H, Shimizu H, Fukami S. [Reration between symptom and counts of scattering Japanese cedar pollen--examination of clinical observation and repeated provocation]. Arerugi 1996; 45:49-61. [PMID: 8851316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
We examined relation with the scattering number of Japanese cedar pollens in Mibu, Tochigi, Japan and a nasal allergy symptom expects from pollen observation at an appearance and symptom progress in detail. We investigated appearance day of nasal allergy symptom and relation with pollen number. High relation was admitted as accumulate rate of nasal allergy as accumulation pollen during a numerical square root. When it was long period of the first observation day of pollen to the first day of pollen scatterring, the rate of nasal allergy symptom became high. An equilateral correlation was admitted as symptom a score in symptom progress and relation with pollen number accumulation pollen during a numerical square root. ECP and tryptase value in nose juice washing liquid rose with progressive of symptom. Early phase reaction progresses in a continuation nose mucous membrane induction examination and ECP in nose juice washing and tryptase rose with it. Late phase reaction was halved with positive group by negative group, progress of reaction by repetition of induction was not accepted. In our conclusion, a symptom is caused by little pollen being exposed repeatedly and that a symptom will become worsen was observed by numerical accumulation pollen.
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Affiliation(s)
- H Yoshida
- Department of Otorhinolaryngology, Dokkyo University School of Medicine
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41
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Sasaki T, Fukami S, Namioka S. Enhancement of cytotoxic activity of lymphocytes in mice by oral administration of peptidoglycan (PG) derived from Bifidobacterium thermophilum. J Vet Med Sci 1994; 56:1129-33. [PMID: 7696404 DOI: 10.1292/jvms.56.1129] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
A preparation of peptidoglycan (PG) of Bifidobacterium thermophilum (B. thermophilum) of swine was orally administered to SPF-C57BL/6CrSlc mice in order to confirm the enhancement of the cytotoxic activity of natural killer cells (NK), intraperitoneal cytotoxic T lymphocytes (CTL) and lymphocytes stimulated by concanavalin A (Con A-stimulated lymphocytes). The NK cells from the spleen and the mesenteric lymph node (MLN) of mice that were continuously fed with PG-mixed feed for three weeks showed a significantly higher rate of cytolysis than those from the control group. However, a single oral administration of PG had no significant effect on NK activity. The activity of peritoneally sensitized CTL of the mice that were continuously fed with PG-mixed feed was assayed. The PG-mixed feed administered group showed a higher CTL activity than that of the control group. The cytotoxic activity of Con A-stimulated lymphocytes in the PG-mixed feed administered group was higher than that of the control group. These results indicate that the cytotoxic activity of mice was enhanced by orally administered PG.
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Affiliation(s)
- T Sasaki
- Zen-noh Institute of Animal Health, Chiba, Japan
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42
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Kuroda S, Kishi Y, Fujino Y, Fukami S, Nishio M, Mima T. [General anesthesia for patients with hypertrophic cardiomyopathy]. Masui 1994; 43:1758-1760. [PMID: 7861612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
General anesthesia was given to six surgical patients with hypertrophic cardiomyopathy on eight occasions from 1990 to 1992. Anesthetic courses were uneventful in five patients diagnosed previously as hypertrophic cardiomyopathy. However, a patient without a diagnosis of hypertrophic cardiomyopathy had intractable cardiac arrest. A slight hypotension caused by epidural anesthesia had a devastating effect on the patient. The above experiences stress the importance of early diagnosis and careful observation in perioperative period.
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Affiliation(s)
- S Kuroda
- Department of Anesthesia, Osaka Prefectural Hospital
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43
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Sasaki T, Fukami S, Namioka S. Enhanced resistance of mice to Escherichia coli infection induced by administration of peptidoglycan derived from Bifidobacterium thermophilum. J Vet Med Sci 1994; 56:433-7. [PMID: 7948368 DOI: 10.1292/jvms.56.433] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Peptidoglycan (PG) of Bifidobacterium thermophilum (B. thermophilum) from swine were orally administered to SPF-ICR mice in order to confirm the enhancement of the defence activity of the mice against Escherichia coli (E. coli) infection. It was found that the survival rates of the PG-administered group were significantly higher than those of the non-treated control group after the single oral administration of PG. And the proper concentration at which PG enhanced defence activity most effectively was found to be 500 micrograms per mouse. The number of E. coli in the peripheral blood, liver and spleen of the PG-administered group at 24 hr after the inoculation was significantly smaller than that in the control group. Liver weight per body weight in the PG treated group significantly increased in comparison with that of the non-treated group. The number of blastoid plasmacytes in the spleen of the PG-administered mice was found to be greater than that in the control group. These results indicate that the defence activity of mice against E. coli infection was accelerated by PG treatment.
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Affiliation(s)
- T Sasaki
- Zen-noh Institute of Animal Health, Chiba, Japan
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44
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Suzuki M, Sugie H, Tsurui S, Miyamoto R, Sugie Y, Igarashi Y, Kaku H, Fukami S. [Benign infantile mitochondrial myopathy due to reversible cytochrome c oxidase deficiency: histological and biochemical analysis]. No To Hattatsu 1989; 21:543-9. [PMID: 2553079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We reported a 3-week-old girl with profound generalized weakness, requiring assisted ventilation. There was no consanguinity or family history of any neuromuscular disorders. Serum levels of GOT, GPT and CK were slightly elevated. Although the clinical manifestations mimicked those of Werdning-Hoffmann disease, a lack of the respiratory muscle involvement and the presence of high serum lactate levels suggested an underlying metabolic disorder. During the observation over the months, she gradually improved clinically and assisted ventilation was discontinued at 19 months. Muscle biopsies were performed at 4 and 19 months of age. The first biopsy showed an excessive mitochondrial aggregation and numerous ragged-red fibers. The second biopsy revealed rare ragged-red fibers. However there were definite neurogenic changes including type grouping and angulated fibers. Cytochrome c oxidase (CCO) stain was positive in less than 5% of fibers in the first biopsy but in all fibers in the second biopsy. Biochemical analysis using muscle specimens showed a decreased CCO activity; 18.5% of the control level in the first biopsy and 53.3% in the second biopsy. Immunocytochemistry showed the presence of immunologically reactive enzyme protein in both biopsies. Clinical manifestations of our patient were almost identical to those of two cases reported by DiMauro, et al (1983). The enzyme defect in this case was reversible in contrast to that in the fatal infantile form of CCO deficiency. Histochemical and biochemical bases for these differences were discussed.
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45
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Suzuki Y, Fujita H, Imano Y, Fukami S, Izumi Y. [Nursing of patients with aplastic anemia--with special reference to guidance of patients concerning daily activities]. Kango Gijutsu 1972; 18:55-63. [PMID: 4482639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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