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Merbouche H, Divinskiy B, Gouéré D, Lebrun R, El Kanj A, Cros V, Bortolotti P, Anane A, Demokritov SO, Demidov VE. True amplification of spin waves in magnonic nano-waveguides. Nat Commun 2024; 15:1560. [PMID: 38378662 PMCID: PMC10879122 DOI: 10.1038/s41467-024-45783-1] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 02/05/2024] [Indexed: 02/22/2024] Open
Abstract
Magnonic nano-devices exploit magnons - quanta of spin waves - to transmit and process information within a single integrated platform that has the potential to outperform traditional semiconductor-based electronics. The main missing cornerstone of this information nanotechnology is an efficient scheme for the amplification of propagating spin waves. The recent discovery of spin-orbit torque provided an elegant mechanism for propagation losses compensation. While partial compensation of the spin-wave losses has been achieved, true amplification - the exponential increase in the spin-wave intensity during propagation - has so far remained elusive. Here we evidence the operating conditions to achieve unambiguous amplification using clocked nanoseconds-long spin-orbit torque pulses in magnonic nano-waveguides, where the effective magnetization has been engineered to be close to zero to suppress the detrimental magnon scattering. We achieve an exponential increase in the intensity of propagating spin waves up to 500% at a propagation distance of several micrometers.
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Affiliation(s)
- H Merbouche
- Institute of Applied Physics, University of Muenster, Corrensstrasse 2-4, 48149, Muenster, Germany
| | - B Divinskiy
- Institute of Applied Physics, University of Muenster, Corrensstrasse 2-4, 48149, Muenster, Germany
| | - D Gouéré
- Laboratoire Albert Fert, CNRS, Thales, Université Paris-Saclay, 91767, Palaiseau, France
| | - R Lebrun
- Laboratoire Albert Fert, CNRS, Thales, Université Paris-Saclay, 91767, Palaiseau, France
| | - A El Kanj
- Laboratoire Albert Fert, CNRS, Thales, Université Paris-Saclay, 91767, Palaiseau, France
| | - V Cros
- Laboratoire Albert Fert, CNRS, Thales, Université Paris-Saclay, 91767, Palaiseau, France
| | - P Bortolotti
- Laboratoire Albert Fert, CNRS, Thales, Université Paris-Saclay, 91767, Palaiseau, France
| | - A Anane
- Laboratoire Albert Fert, CNRS, Thales, Université Paris-Saclay, 91767, Palaiseau, France
| | - S O Demokritov
- Institute of Applied Physics, University of Muenster, Corrensstrasse 2-4, 48149, Muenster, Germany
| | - V E Demidov
- Institute of Applied Physics, University of Muenster, Corrensstrasse 2-4, 48149, Muenster, Germany.
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2
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Divinskiy B, Merbouche H, Demidov VE, Nikolaev KO, Soumah L, Gouéré D, Lebrun R, Cros V, Youssef JB, Bortolotti P, Anane A, Demokritov SO. Evidence for spin current driven Bose-Einstein condensation of magnons. Nat Commun 2021; 12:6541. [PMID: 34764266 PMCID: PMC8585877 DOI: 10.1038/s41467-021-26790-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [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: 04/14/2021] [Accepted: 10/22/2021] [Indexed: 11/26/2022] Open
Abstract
The quanta of magnetic excitations - magnons - are known for their unique ability to undergo Bose-Einstein condensation at room temperature. This fascinating phenomenon reveals itself as a spontaneous formation of a coherent state under the influence of incoherent stimuli. Spin currents have been predicted to offer electronic control of Bose-Einstein condensates, but this phenomenon has not been experimentally evidenced up to now. Here we show that current-driven Bose-Einstein condensation can be achieved in nanometer-thick films of magnetic insulators with tailored nonlinearities and minimized magnon interactions. We demonstrate that, above a certain threshold, magnons injected by the spin current overpopulate the lowest-energy level forming a highly coherent spatially extended state. We quantify the chemical potential of the driven magnon gas and show that, at the critical current, it reaches the energy of the lowest magnon level. Our results pave the way for implementation of integrated microscopic quantum magnonic and spintronic devices.
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Affiliation(s)
- B Divinskiy
- Institute for Applied Physics, University of Muenster, Corrensstrasse 2-4, 48149, Muenster, Germany
| | - H Merbouche
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767, Palaiseau, France
| | - V E Demidov
- Institute for Applied Physics, University of Muenster, Corrensstrasse 2-4, 48149, Muenster, Germany.
| | - K O Nikolaev
- Institute for Applied Physics, University of Muenster, Corrensstrasse 2-4, 48149, Muenster, Germany
| | - L Soumah
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767, Palaiseau, France
| | - D Gouéré
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767, Palaiseau, France
| | - R Lebrun
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767, Palaiseau, France
| | - V Cros
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767, Palaiseau, France
| | - Jamal Ben Youssef
- LABSTICC, UMR 6285 CNRS, Université de Bretagne Occidentale, 29238, Brest, France
| | - P Bortolotti
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767, Palaiseau, France
| | - A Anane
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767, Palaiseau, France
| | - S O Demokritov
- Institute for Applied Physics, University of Muenster, Corrensstrasse 2-4, 48149, Muenster, Germany
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3
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Riou M, Torrejon J, Garitaine B, Araujo FA, Bortolotti P, Cros V, Tsunegi S, Yakushiji K, Fukushima A, Kubota H, Yuasa S, Querlioz D, Stiles MD, Grollier J. Temporal pattern recognition with delayed feedback spin-torque nano-oscillators. Phys Rev Appl 2019; 12:10.1103/physrevapplied.12.024049. [PMID: 32118096 PMCID: PMC7047780 DOI: 10.1103/physrevapplied.12.024049] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The recent demonstration of neuromorphic computing with spin-torque nano-oscillators has opened a path to energy efficient data processing. The success of this demonstration hinged on the intrinsic short-term memory of the oscillators. In this study, we extend the memory of the spin-torque nano-oscillators through time-delayed feedback. We leverage this extrinsic memory to increase the efficiency of solving pattern recognition tasks that require memory to discriminate different inputs. The large tunability of these non-linear oscillators allows us to control and optimize the delayed feedback memory using different operating conditions of applied current and magnetic field.
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Affiliation(s)
- M Riou
- Unité Mixte de Physique CNRS, Thales,Université Paris-Sud, Université Paris-Saclay, 91767 Palaiseau, France
| | - J Torrejon
- Unité Mixte de Physique CNRS, Thales,Université Paris-Sud, Université Paris-Saclay, 91767 Palaiseau, France
| | - B Garitaine
- Unité Mixte de Physique CNRS, Thales,Université Paris-Sud, Université Paris-Saclay, 91767 Palaiseau, France
| | - F Abreu Araujo
- Unité Mixte de Physique CNRS, Thales,Université Paris-Sud, Université Paris-Saclay, 91767 Palaiseau, France
| | - P Bortolotti
- Unité Mixte de Physique CNRS, Thales,Université Paris-Sud, Université Paris-Saclay, 91767 Palaiseau, France
| | - V Cros
- Unité Mixte de Physique CNRS, Thales,Université Paris-Sud, Université Paris-Saclay, 91767 Palaiseau, France
| | - S Tsunegi
- National Institute of Advanced Industrial Science and Technology (AIST), Spintronic Research Center, Tsukuba, Ibaraki 305-8568, Japan
| | - K Yakushiji
- National Institute of Advanced Industrial Science and Technology (AIST), Spintronic Research Center, Tsukuba, Ibaraki 305-8568, Japan
| | - A Fukushima
- National Institute of Advanced Industrial Science and Technology (AIST), Spintronic Research Center, Tsukuba, Ibaraki 305-8568, Japan
| | - H Kubota
- National Institute of Advanced Industrial Science and Technology (AIST), Spintronic Research Center, Tsukuba, Ibaraki 305-8568, Japan
| | - S Yuasa
- National Institute of Advanced Industrial Science and Technology (AIST), Spintronic Research Center, Tsukuba, Ibaraki 305-8568, Japan
| | - D Querlioz
- Center for Nanoscience and Nanotechnology, CNRS, Université Paris-Sud, Université Paris-Saclay, 91405, Orsay, France
| | - M D Stiles
- Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-6202, USA
| | - J Grollier
- Unité Mixte de Physique CNRS, Thales,Université Paris-Sud, Université Paris-Saclay, 91767 Palaiseau, France
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McVitie S, Hughes S, Fallon K, McFadzean S, McGrouther D, Krajnak M, Legrand W, Maccariello D, Collin S, Garcia K, Reyren N, Cros V, Fert A, Zeissler K, Marrows CH. A transmission electron microscope study of Néel skyrmion magnetic textures in multilayer thin film systems with large interfacial chiral interaction. Sci Rep 2018; 8:5703. [PMID: 29632330 PMCID: PMC5890272 DOI: 10.1038/s41598-018-23799-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [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: 11/22/2017] [Accepted: 03/21/2018] [Indexed: 12/05/2022] Open
Abstract
Skyrmions in ultrathin ferromagnetic metal (FM)/heavy metal (HM) multilayer systems produced by conventional sputtering methods have recently generated huge interest due to their applications in the field of spintronics. The sandwich structure with two correctly-chosen heavy metal layers provides an additive interfacial exchange interaction which promotes domain wall or skyrmion spin textures that are Néel in character and with a fixed chirality. Lorentz transmission electron microscopy (TEM) is a high resolution method ideally suited to quantitatively image such chiral magnetic configurations. When allied with physical and chemical TEM analysis of both planar and cross-sectional samples, key length scales such as grain size and the chiral variation of the magnetisation variation have been identified and measured. We present data showing the importance of the grain size (mostly < 10 nm) measured from direct imaging and its potential role in describing observed behaviour of isolated skyrmions (diameter < 100 nm). In the latter the region in which the magnetization rotates is measured to be around 30 nm. Such quantitative information on the multiscale magnetisation variations in the system is key to understanding and exploiting the behaviour of skyrmions for future applications in information storage and logic devices.
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Affiliation(s)
- S McVitie
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, United Kingdom.
| | - S Hughes
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - K Fallon
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - S McFadzean
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - D McGrouther
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, United Kingdom
| | - M Krajnak
- Scottish Universities Physics Alliance, School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, United Kingdom.,Department of Materials Science and Engineering, Monash University, Clayton, Victoria, 3800, Australia
| | - W Legrand
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, 91767, Palaiseau, France
| | - D Maccariello
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, 91767, Palaiseau, France
| | - S Collin
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, 91767, Palaiseau, France
| | - K Garcia
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, 91767, Palaiseau, France
| | - N Reyren
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, 91767, Palaiseau, France
| | - V Cros
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, 91767, Palaiseau, France
| | - A Fert
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, 91767, Palaiseau, France
| | - K Zeissler
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - C H Marrows
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, United Kingdom
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5
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Bousquet J, Bourret R, Camuzat T, Augé P, Bringer J, Noguès M, Jonquet O, de la Coussaye JE, Ankri J, Cesari M, Guérin O, Vellas B, Blain H, Arnavielhe S, Avignon A, Combe B, Canovas G, Daien C, Dray G, Dupeyron A, Jeandel C, Laffont I, Laune D, Marion C, Pastor E, Pélissier JY, Galan B, Reynes J, Reuzeau JC, Bedbrook A, Granier S, Adnet PA, Amouyal M, Alomène B, Bernard PL, Berr C, Caimmi D, Claret PG, Costa DJ, Cristol JP, Fesler P, Hève D, Millot-Keurinck J, Morquin D, Ninot G, Picot MC, Raffort N, Roubille F, Sultan A, Touchon J, Attalin V, Azevedo C, Badin M, Bakhti K, Bardy B, Battesti MP, Bobia X, Boegner C, Boichot S, Bonnin HY, Bouly S, Boubakri C, Bourrain JL, Bourrel G, Bouix V, Bruguière V, Cade S, Camu W, Carre V, Cavalli G, Cayla G, Chiron R, Coignard P, Coroian F, Costa P, Cottalorda J, Coulet B, Coupet AL, Courrouy-Michel MC, Courtet P, Cros V, Cuisinier F, Danko M, Dauenhauer P, Dauzat M, David M, Davy JM, Delignières D, Demoly P, Desplan J, Dujols P, Dupeyron G, Engberink O, Enjalbert M, Fattal C, Fernandes J, Fouletier M, Fraisse P, Gabrion P, Gellerat-Rogier M, Gelis A, Genis C, Giraudeau N, Goucham AY, Gouzi F, Gressard F, Gris JC, Guillot B, Guiraud D, Handweiler V, Hayot M, Hérisson C, Heroum C, Hoa D, Jacquemin S, Jaber S, Jakovenko D, Jorgensen C, Kouyoudjian P, Lamoureux R, Landreau L, Lapierre M, Larrey D, Laurent C, Léglise MS, Lemaitre JM, Le Quellec A, Leclercq F, Lehmann S, Lognos B, Lussert CM, Makinson A, Mandrick K, Mares P, Martin-Gousset P, Matheron A, Mathieu G, Meissonnier M, Mercier G, Messner P, Meunier C, Mondain M, Morales R, Morel J, Mottet D, Nérin P, Nicolas P, Nouvel F, Paccard D, Pandraud G, Pasdelou MP, Pasquié JL, Patte K, Perrey S, Pers YM, Portejoie F, Pujol JLE, Quantin X, Quéré I, Ramdani S, Ribstein J, Rédini-Martinez I, Richard S, Ritchie K, Riso JP, Rivier F, Robine JM, Rolland C, Royère E, Sablot D, Savy JL, Schifano L, Senesse P, Sicard R, Stephan Y, Strubel D, Tallon G, Tanfin M, Tassery H, Tavares I, Torre K, Tribout V, Uziel A, Van de Perre P, Venail F, Vergne-Richard C, Vergotte G, Vian L, Vialla F, Viart F, Villain M, Viollet E, Ychou M, Mercier J. MACVIA-LR (Fighting Chronic Diseases for Active and Healthy Ageing in Languedoc-Roussillon): A Success Story of the European Innovation Partnership on Active and Healthy Ageing. J Frailty Aging 2017; 5:233-241. [PMID: 27883170 DOI: 10.14283/jfa.2016.105] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The Région Languedoc Roussillon is the umbrella organisation for an interconnected and integrated project on active and healthy ageing (AHA). It covers the 3 pillars of the European Innovation Partnership on Active and Healthy Ageing (EIP on AHA): (A) Prevention and health promotion, (B) Care and cure, (C) and (D) Active and independent living of elderly people. All sub-activities (poly-pharmacy, falls prevention initiative, prevention of frailty, chronic respiratory diseases, chronic diseases with multimorbidities, chronic infectious diseases, active and independent living and disability) have been included in MACVIA-LR which has a strong political commitment and involves all stakeholders (public, private, patients, policy makers) including CARSAT-LR and the Eurobiomed cluster. It is a Reference Site of the EIP on AHA. The framework of MACVIA-LR has the vision that the prevention and management of chronic diseases is essential for the promotion of AHA and for the reduction of handicap. The main objectives of MACVIA-LR are: (i) to develop innovative solutions for a network of Living labs in order to reduce avoidable hospitalisations and loss of autonomy while improving quality of life, (ii) to disseminate the innovation. The three years of MACVIA-LR activities are reported in this paper.
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Affiliation(s)
- J Bousquet
- Professor Jean Bousquet, CHRU, 371 Avenue du Doyen Gaston Giraud, 34295 Montpellier Cedex 5, France, Tel +33 611 42 88 47,
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Riou M, Araujo FA, Torrejon J, Tsunegi S, Khalsa G, Querlioz D, Bortolotti P, Cros V, Yakushiji K, Fukushima A, Kubota H, Yuasa S, Stiles MD, Grollier J. Neuromorphic Computing through Time-Multiplexing with a Spin-Torque Nano-Oscillator. IEEE Trans Electron Devices 2017; IEDM 2017:10.1109/IEDM.2017.8268505. [PMID: 31080272 PMCID: PMC6508600 DOI: 10.1109/iedm.2017.8268505] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Fabricating powerful neuromorphic chips the size of a thumb requires miniaturizing their basic units: synapses and neurons. The challenge for neurons is to scale them down to submicrometer diameters while maintaining the properties that allow for reliable information processing: high signal to noise ratio, endurance, stability, reproducibility. In this work, we show that compact spin-torque nano-oscillators can naturally implement such neurons, and quantify their ability to realize an actual cognitive task. In particular, we show that they can naturally implement reservoir computing with high performance and detail the recipes for this capability.
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Affiliation(s)
- M Riou
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, France
| | - F Abreu Araujo
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, France
| | - J Torrejon
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, France
| | - S Tsunegi
- National Institute of Advanced Industrial Science and Technology (AIST), Spintronics Research Center, Tsukuba, Japan
| | - G Khalsa
- Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, MD, USA
| | - D Querlioz
- Centre de Nanosciences et de Nanotechnologies, CNRS, Univ. Paris-Sud, Université Paris-Saclay, France
| | - P Bortolotti
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, France
| | - V Cros
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, France
| | - K Yakushiji
- National Institute of Advanced Industrial Science and Technology (AIST), Spintronics Research Center, Tsukuba, Japan
| | - A Fukushima
- National Institute of Advanced Industrial Science and Technology (AIST), Spintronics Research Center, Tsukuba, Japan
| | - H Kubota
- National Institute of Advanced Industrial Science and Technology (AIST), Spintronics Research Center, Tsukuba, Japan
| | - S Yuasa
- National Institute of Advanced Industrial Science and Technology (AIST), Spintronics Research Center, Tsukuba, Japan
| | - M D Stiles
- Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, MD, USA
| | - J Grollier
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, France
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7
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Moreau-Luchaire C, Moutafis C, Reyren N, Sampaio J, Vaz CAF, Van Horne N, Bouzehouane K, Garcia K, Deranlot C, Warnicke P, Wohlhüter P, George JM, Weigand M, Raabe J, Cros V, Fert A. Erratum: Additive interfacial chiral interaction in multilayers for stabilization of small individual skyrmions at room temperature. Nat Nanotechnol 2016; 11:731. [PMID: 27485585 DOI: 10.1038/nnano.2016.107] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
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Moreau-Luchaire C, Mouta S C, Reyren N, Sampaio J, Vaz CAF, Van Horne N, Bouzehouane K, Garcia K, Deranlot C, Warnicke P, Wohlhüter P, George JM, Weigand M, Raabe J, Cros V, Fert A. Additive interfacial chiral interaction in multilayers for stabilization of small individual skyrmions at room temperature. Nat Nanotechnol 2016; 11:444-8. [PMID: 26780660 DOI: 10.1038/nnano.2015.313] [Citation(s) in RCA: 270] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 11/30/2015] [Indexed: 05/12/2023]
Abstract
Facing the ever-growing demand for data storage will most probably require a new paradigm. Nanoscale magnetic skyrmions are anticipated to solve this issue as they are arguably the smallest spin textures in magnetic thin films in nature. We designed cobalt-based multilayered thin films in which the cobalt layer is sandwiched between two heavy metals and so provides additive interfacial Dzyaloshinskii-Moriya interactions (DMIs), which reach a value close to 2 mJ m(-2) in the case of the Ir|Co|Pt asymmetric multilayers. Using a magnetization-sensitive scanning X-ray transmission microscopy technique, we imaged small magnetic domains at very low fields in these multilayers. The study of their behaviour in a perpendicular magnetic field allows us to conclude that they are actually magnetic skyrmions stabilized by the large DMI. This discovery of stable sub-100 nm individual skyrmions at room temperature in a technologically relevant material opens the way for device applications in the near future.
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Affiliation(s)
- C Moreau-Luchaire
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, Palaiseau 91767, France
| | - C Mouta S
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen, Switzerland
- School of Computer Science, University of Manchester, Manchester M13 9PL, UK
| | - N Reyren
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, Palaiseau 91767, France
| | - J Sampaio
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, Palaiseau 91767, France
| | - C A F Vaz
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - N Van Horne
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, Palaiseau 91767, France
| | - K Bouzehouane
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, Palaiseau 91767, France
| | - K Garcia
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, Palaiseau 91767, France
| | - C Deranlot
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, Palaiseau 91767, France
| | - P Warnicke
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - P Wohlhüter
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen, Switzerland
- Laboratory for Mesoscopic Systems, Department of Materials, ETH Zurich, 8093 Zurich, Switzerland
| | - J-M George
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, Palaiseau 91767, France
| | - M Weigand
- Max Planck Institute for Intelligent Systems, 70569 Stuttgart, Germany
| | - J Raabe
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - V Cros
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, Palaiseau 91767, France
| | - A Fert
- Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, Palaiseau 91767, France
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9
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Yu H, d' Allivy Kelly O, Cros V, Bernard R, Bortolotti P, Anane A, Brandl F, Heimbach F, Grundler D. Approaching soft X-ray wavelengths in nanomagnet-based microwave technology. Nat Commun 2016; 7:11255. [PMID: 27063401 PMCID: PMC4831022 DOI: 10.1038/ncomms11255] [Citation(s) in RCA: 111] [Impact Index Per Article: 13.9] [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: 11/04/2015] [Accepted: 03/07/2016] [Indexed: 12/25/2022] Open
Abstract
Seven decades after the discovery of collective spin excitations in microwave-irradiated ferromagnets, there has been a rebirth of magnonics. However, magnetic nanodevices will enable smart GHz-to-THz devices at low power consumption only, if such spin waves (magnons) are generated and manipulated on the sub-100 nm scale. Here we show how magnons with a wavelength of a few 10 nm are exploited by combining the functionality of insulating yttrium iron garnet and nanodisks from different ferromagnets. We demonstrate magnonic devices at wavelengths of 88 nm written/read by conventional coplanar waveguides. Our microwave-to-magnon transducers are reconfigurable and thereby provide additional functionalities. The results pave the way for a multi-functional GHz technology with unprecedented miniaturization exploiting nanoscale wavelengths that are otherwise relevant for soft X-rays. Nanomagnonics integrated with broadband microwave circuitry offer applications that are wide ranging, from nanoscale microwave components to nonlinear data processing, image reconstruction and wave-based logic.
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Affiliation(s)
- Haiming Yu
- Physik Department E10, Technische Universität München, James-Franck-Strasse 1, D-85748 Garching bei München, Germany.,Fert Beijing Institute, School of Electronic and Information Engineering, Beihang University, Xueyuan Road 37, Beijing 100191, China
| | - O d' Allivy Kelly
- Unité Mixte de Physique, CNRS, Thales, Univ Paris-Sud, Université Paris-Saclay, 91767 Palaiseau, France
| | - V Cros
- Unité Mixte de Physique, CNRS, Thales, Univ Paris-Sud, Université Paris-Saclay, 91767 Palaiseau, France
| | - R Bernard
- Unité Mixte de Physique, CNRS, Thales, Univ Paris-Sud, Université Paris-Saclay, 91767 Palaiseau, France
| | - P Bortolotti
- Unité Mixte de Physique, CNRS, Thales, Univ Paris-Sud, Université Paris-Saclay, 91767 Palaiseau, France
| | - A Anane
- Unité Mixte de Physique, CNRS, Thales, Univ Paris-Sud, Université Paris-Saclay, 91767 Palaiseau, France
| | - F Brandl
- Physik Department E10, Technische Universität München, James-Franck-Strasse 1, D-85748 Garching bei München, Germany
| | - F Heimbach
- Physik Department E10, Technische Universität München, James-Franck-Strasse 1, D-85748 Garching bei München, Germany
| | - D Grundler
- Physik Department E10, Technische Universität München, James-Franck-Strasse 1, D-85748 Garching bei München, Germany.,Laboratory of Nanoscale Magnetic Materials and Magnonics, Institute of Materials, School of Engineering, École Polytechnique Fédérale de Lausanne, STI-IMX-LMGN, Station 17, CH-1015 Lausanne, Switzerland
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10
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Jenkins AS, Lebrun R, Grimaldi E, Tsunegi S, Bortolotti P, Kubota H, Yakushiji K, Fukushima A, de Loubens G, Klein O, Yuasa S, Cros V. Spin-torque resonant expulsion of the vortex core for an efficient radiofrequency detection scheme. Nat Nanotechnol 2016; 11:360-364. [PMID: 26727200 DOI: 10.1038/nnano.2015.295] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Accepted: 11/17/2015] [Indexed: 06/05/2023]
Abstract
It has been proposed that high-frequency detectors based on the so-called spin-torque diode effect in spin transfer oscillators could eventually replace conventional Schottky diodes due to their nanoscale size, frequency tunability and large output sensitivity. Although a promising candidate for information and communications technology applications, the output voltage generated from this effect has still to be improved and, more pertinently, reduces drastically with decreasing radiofrequency (RF) current. Here we present a scheme for a new type of spintronics-based high-frequency detector based on the expulsion of the vortex core in a magnetic tunnel junction (MTJ). The resonant expulsion of the core leads to a large and sharp change in resistance associated with the difference in magnetoresistance between the vortex ground state and the final C-state configuration. Interestingly, this reversible effect is independent of the incoming RF current amplitude, offering a fast real-time RF threshold detector.
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Affiliation(s)
- A S Jenkins
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud, 91767 Palaiseau, France
| | - R Lebrun
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud, 91767 Palaiseau, France
| | - E Grimaldi
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud, 91767 Palaiseau, France
| | - S Tsunegi
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud, 91767 Palaiseau, France
- Institute of Advanced Industrial Science and Technology (AIST), Spintronics Research Center, Tsukuba, 305-8560 Japan
| | - P Bortolotti
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud, 91767 Palaiseau, France
| | - H Kubota
- Institute of Advanced Industrial Science and Technology (AIST), Spintronics Research Center, Tsukuba, 305-8560 Japan
| | - K Yakushiji
- Institute of Advanced Industrial Science and Technology (AIST), Spintronics Research Center, Tsukuba, 305-8560 Japan
| | - A Fukushima
- Institute of Advanced Industrial Science and Technology (AIST), Spintronics Research Center, Tsukuba, 305-8560 Japan
| | - G de Loubens
- Service de Physique de l'Etat Condensé (CNRS URA 2464), CEA Saclay, 91191 Gif-sur-Yvette, France
| | - O Klein
- Service de Physique de l'Etat Condensé (CNRS URA 2464), CEA Saclay, 91191 Gif-sur-Yvette, France
| | - S Yuasa
- Institute of Advanced Industrial Science and Technology (AIST), Spintronics Research Center, Tsukuba, 305-8560 Japan
| | - V Cros
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud, 91767 Palaiseau, France
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11
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Collet M, de Milly X, d'Allivy Kelly O, Naletov VV, Bernard R, Bortolotti P, Ben Youssef J, Demidov VE, Demokritov SO, Prieto JL, Muñoz M, Cros V, Anane A, de Loubens G, Klein O. Generation of coherent spin-wave modes in yttrium iron garnet microdiscs by spin-orbit torque. Nat Commun 2016; 7:10377. [PMID: 26815737 PMCID: PMC4737803 DOI: 10.1038/ncomms10377] [Citation(s) in RCA: 188] [Impact Index Per Article: 23.5] [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: 05/24/2015] [Accepted: 12/04/2015] [Indexed: 12/02/2022] Open
Abstract
In recent years, spin–orbit effects have been widely used to produce and detect spin currents in spintronic devices. The peculiar symmetry of the spin Hall effect allows creation of a spin accumulation at the interface between a metal with strong spin–orbit interaction and a magnetic insulator, which can lead to a net pure spin current flowing from the metal into the insulator. This spin current applies a torque on the magnetization, which can eventually be driven into steady motion. Tailoring this experiment on extended films has proven to be elusive, probably due to mode competition. This requires the reduction of both the thickness and lateral size to reach full damping compensation. Here we show clear evidence of coherent spin–orbit torque-induced auto-oscillation in micron-sized yttrium iron garnet discs of thickness 20 nm. Our results emphasize the key role of quasi-degenerate spin-wave modes, which increase the threshold current. Spin-orbit interactions allow for pure spin current to be injected into a ferromagnetic insulator from a current-carrying heavy metal, generating torque on the magnetization. Here, the authors evidence magnetic auto-oscillations driven by spin-orbit torque in thin film microdiscs of yttrium iron garnet.
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Affiliation(s)
- M Collet
- Unité Mixte de Physique CNRS, Thales, Université Paris-Sud, Université Paris-Saclay, 1 avenue A. Fresnel, 91767 Palaiseau, France
| | - X de Milly
- Service de Physique de l'État Condensé, CEA, CNRS, Université Paris-Saclay, CEA Saclay, Orme des Merisiers, 91191 Gif-sur-Yvette, France
| | - O d'Allivy Kelly
- Unité Mixte de Physique CNRS, Thales, Université Paris-Sud, Université Paris-Saclay, 1 avenue A. Fresnel, 91767 Palaiseau, France
| | - V V Naletov
- INAC-SPINTEC, CEA, CNRS and Université Grenoble Alpes, 17 avenue des Martyrs, 38000 Grenoble, France.,Institute of Physics, Kazan Federal University, Kazan 420008, Russian Federation
| | - R Bernard
- Unité Mixte de Physique CNRS, Thales, Université Paris-Sud, Université Paris-Saclay, 1 avenue A. Fresnel, 91767 Palaiseau, France
| | - P Bortolotti
- Unité Mixte de Physique CNRS, Thales, Université Paris-Sud, Université Paris-Saclay, 1 avenue A. Fresnel, 91767 Palaiseau, France
| | - J Ben Youssef
- Laboratoire de Magnétisme de Bretagne CNRS, Université de Bretagne Occidentale, 6 Avenue Le Gorgeu, 29285 Brest, France
| | - V E Demidov
- Department of Physics, University of Muenster, Correnstrasse 2-4, 48149 Muenster, Germany
| | - S O Demokritov
- Department of Physics, University of Muenster, Correnstrasse 2-4, 48149 Muenster, Germany.,Institute of Metal Physics, Ural Division of RAS, Yekaterinburg 620041, Russian Federation
| | - J L Prieto
- Instituto de Sistemas Optoelectrónicos y Microtecnologa (UPM), Ciudad Universitaria, Madrid 28040, Spain
| | - M Muñoz
- IMM-Instituto de Microelectrónica de Madrid (CNM-CSIC), Isaac Newton 8, PTM, Tres Cantos, Madrid E-28760, Spain
| | - V Cros
- Unité Mixte de Physique CNRS, Thales, Université Paris-Sud, Université Paris-Saclay, 1 avenue A. Fresnel, 91767 Palaiseau, France
| | - A Anane
- Unité Mixte de Physique CNRS, Thales, Université Paris-Sud, Université Paris-Saclay, 1 avenue A. Fresnel, 91767 Palaiseau, France
| | - G de Loubens
- Service de Physique de l'État Condensé, CEA, CNRS, Université Paris-Saclay, CEA Saclay, Orme des Merisiers, 91191 Gif-sur-Yvette, France
| | - O Klein
- INAC-SPINTEC, CEA, CNRS and Université Grenoble Alpes, 17 avenue des Martyrs, 38000 Grenoble, France
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12
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Bousquet J, Bourret R, Camuzat T, Augé P, Domy P, Bringer J, Best N, Jonquet O, de la Coussaye JE, Noguès M, Robine JM, Avignon A, Blain H, Combe B, Dray G, Dufour V, Fouletier M, Giraudeau N, Hève D, Jeandel C, Laffont I, Larrey D, Laune D, Laurent C, Mares P, Marion C, Pastor E, Pélissier JY, Radier-Pontal F, Reynes J, Royère E, Ychou M, Bedbrook A, Granier S, Abecassis F, Albert S, Adnet PA, Alomène B, Amouyal M, Arnavielhe S, Asteriou T, Attalin V, Aubas P, Azevedo C, Badin M, Bakhti, Baptista G, Bardy B, Battesti MP, Bénézet O, Bernard PL, Berr C, Berthe J, Bobia X, Bockaert J, Boegner C, Boichot S, Bonnin HY, Boulet P, Bouly S, Boubakri C, Bourdin A, Bourrain JL, Bourrel G, Bouix V, Breuker C, Bruguière V, Burille J, Cade S, Caimmi D, Calmels MV, Camu W, Canovas G, Carre V, Cavalli G, Cayla G, Chiron R, Claret PG, Coignard P, Coroian F, Costa DJ, Costa P, Cottalorda, Coulet B, Coupet AL, Courrouy-Michel MC, Courtet P, Cristol JP, Cros V, Cuisinier F, Daien C, Danko M, Dauenhauer P, Dauzat M, David M, Davy JM, Delignières D, Demoly P, Desplan J, Dhivert-Donnadieu H, Dujols P, Dupeyron A, Dupeyron G, Engberink O, Enjalbert M, Fattal C, Fernandes J, Fesler P, Fraisse P, Froger J, Gabrion P, Galano E, Gellerat-Rogier M, Gellis A, Goucham AY, Gouzi F, Gressard F, Gris JC, Guillot B, Guiraud D, Handweiler V, Hantkié H, Hayot M, Hérisson C, Heroum C, Hoa D, Jacquemin S, Jaber S, Jakovenko D, Jorgensen C, Journot L, Kaczorek M, Kouyoudjian P, Labauge P, Landreau L, Lapierre M, Leblond C, Léglise MS, Lemaitre JM, Le Moing V, Le Quellec A, Leclercq F, Lehmann S, Lognos B, Lussert JM, Makinson A, Mandrick K, Marmelat V, Martin-Gousset P, Matheron A, Mathieu G, Meissonnier M, Mercier G, Messner P, Meunier C, Mondain M, Morales R, Morel J, Morquin D, Mottet D, Nérin P, Nicolas P, Ninot G, Nouvel F, Ortiz JP, Paccard D, Pandraud G, Pasdelou MP, Pasquié JL, Patte K, Perrey S, Pers YM, Picot MC, Pin JP, Pinto N, Porte E, Portejoie F, Pujol JL, Quantin X, Quéré I, Raffort N, Ramdani S, Ribstein J, Rédini-Martinez I, Richard S, Ritchie K, Riso JP, Rivier F, Rolland C, Roubille F, Sablot D, Savy JL, Schifano L, Senesse P, Sicard R, Soua B, Stephan Y, Strubel D, Sultan A, Taddei-Ologeanu, Tallon G, Tanfin M, Tassery H, Tavares I, Torre K, Touchon J, Tribout V, Uziel A, Van de Perre P, Vasquez X, Verdier JM, Vergne-Richard C, Vergotte G, Vian L, Viarouge-Reunier C, Vialla F, Viart F, Villain M, Villiet M, Viollet E, Wojtusciszyn A, Aoustin M, Bourquin C, Mercier J. Introduction. Presse Med 2015; 44 Suppl 1:S1-5. [DOI: 10.1016/j.lpm.2015.07.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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13
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Laffont I, Jourdan C, Coroian F, Blain H, Carre V, Viollet E, Tavares I, Fattal C, Gelis A, Nouvel F, Bakhti K, Cros V, Patte K, Schifano L, Porte M, Galano E, Dray G, Fouletier M, Rivier F, Morales R, Labauge P, Camu W, Combe B, Morel J, Froger J, Coulet B, Cottalorda J, Kouyoumdjian P, Jonquet O, Landreau L, Bonnin HY, Hantkié O, Nicolas P, Enjalbert M, Leblond C, Soua B, Coignard P, Guiraud D, Azevedo C, Mottet D, Fraisse P, Pastor E, Mercier J, Bourret R, Bousquet J, Pélissier J, Bardy B, Herisson C, Dupeyron A. [Living Lab MACVIA. Disability]. Presse Med 2015; 44 Suppl 1:S60-9. [PMID: 26482491 DOI: 10.1016/j.lpm.2015.07.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Affiliation(s)
- I Laffont
- CHRU de Montpellier, département de médecine physique et de réadaptation, 34090 Montpellier, France; Movement to Health (M2H), Euromov, université de Montpellier, Montpellier, France.
| | - C Jourdan
- CHRU de Montpellier, département de médecine physique et de réadaptation, 34090 Montpellier, France
| | - F Coroian
- CHRU de Montpellier, département de médecine physique et de réadaptation, 34090 Montpellier, France; Movement to Health (M2H), Euromov, université de Montpellier, Montpellier, France
| | - H Blain
- Movement to Health (M2H), Euromov, université de Montpellier, Montpellier, France; CHRU de Montpellier, département de gériatrie, 34090 Montpellier, France
| | - V Carre
- CHRU de Montpellier, département de médecine physique et de réadaptation, 34090 Montpellier, France
| | - E Viollet
- CHU de Nîmes, hôpital Carémeau et du Grau du Roi, département de médecine physique et de réadaptation, 30029 Nîmes, France; CHU Carémeau, CEDMH, 30029 Nîmes, France
| | - I Tavares
- CHRU de Montpellier, département de médecine physique et de réadaptation, 34090 Montpellier, France
| | - C Fattal
- Association APPROCHE, CMRRF de Kerpape, BP 78, 56275 Ploemeur cedex, France
| | - A Gelis
- Centre Mutualiste Propara, 34000 Montpellier, France
| | - F Nouvel
- CHU Carémeau, CEDMH, 30029 Nîmes, France
| | - K Bakhti
- CHRU de Montpellier, département de médecine physique et de réadaptation, 34090 Montpellier, France; Movement to Health (M2H), Euromov, université de Montpellier, Montpellier, France
| | - V Cros
- CHRU de Montpellier, département de médecine physique et de réadaptation, 34090 Montpellier, France
| | - K Patte
- Institut Marin Saint-Pierre, 34250 Palavas les Flots, France
| | - L Schifano
- Institut Marin Saint-Pierre, 34250 Palavas les Flots, France
| | - M Porte
- CHU de Nîmes, hôpital Carémeau et du Grau du Roi, département de médecine physique et de réadaptation, 30029 Nîmes, France
| | - E Galano
- CHU de Nîmes, hôpital Carémeau et du Grau du Roi, département de médecine physique et de réadaptation, 30029 Nîmes, France
| | - G Dray
- École des Mines d'Alès, 30100 Alès, France
| | | | - F Rivier
- CHU de Montpellier, centre de référence Grand Sud des maladies neuromusculaires, département de neuropédiatrie, 34090 Montpellier, France
| | - R Morales
- CHRU de Montpellier, département de neurologie, 34090 Montpellier, France
| | - P Labauge
- CHRU de Montpellier, département de neurologie, 34090 Montpellier, France
| | - W Camu
- CHRU de Montpellier, département de neurologie, 34090 Montpellier, France
| | - B Combe
- CHRU de Montpellier, département de rhumatologie, 34090 Montpellier, France
| | - J Morel
- CHRU de Montpellier, département de rhumatologie, 34090 Montpellier, France
| | - J Froger
- Movement to Health (M2H), Euromov, université de Montpellier, Montpellier, France; CHU de Nîmes, hôpital Carémeau et du Grau du Roi, département de médecine physique et de réadaptation, 30029 Nîmes, France
| | - B Coulet
- CHRU de Montpellier, département de chirurgie orthopédique, 34090 Montpellier, France
| | - J Cottalorda
- CHRU de Montpellier, département de chirurgie orthopédique et plastique infantile, 34090 Montpellier, France
| | - P Kouyoumdjian
- CHU Carémeau, département de chirurgie orthopédique, 30029 Nîmes, France
| | - O Jonquet
- CHRU de Montpellier, département de réanimation, 34090 Montpellier, France
| | - L Landreau
- CHRU de Montpellier, département de réanimation, 34090 Montpellier, France
| | - H-Y Bonnin
- Movement to Health (M2H), Euromov, université de Montpellier, Montpellier, France; CHU de Nîmes, hôpital Carémeau et du Grau du Roi, département de médecine physique et de réadaptation, 30029 Nîmes, France
| | - O Hantkié
- Centre Bourgès, groupe Oc Santé, 34173 Castelneau-le-lez cedex, France
| | - P Nicolas
- Centre Bourgès, groupe Oc Santé, 34173 Castelneau-le-lez cedex, France
| | - M Enjalbert
- Centre Bouffard-Vercelli, 66290 Cerbère, France; Association APPROCHE, CMRRF de Kerpape, BP 78, 56275 Ploemeur cedex, France
| | - C Leblond
- Centre Bouffard-Vercelli, 66290 Cerbère, France
| | - B Soua
- Association ADAGES, Les Fontaines d'Ô, 34000 Montpellier, France
| | - P Coignard
- Association APPROCHE, CMRRF de Kerpape, BP 78, 56275 Ploemeur cedex, France
| | - D Guiraud
- Université de Montpellier, laboratoire d'informatique, de robotique et de microélectronique de Montpellier, 34090 Montpellier, France; Institut national de recherche en informatique et en automatique, LIRMM, université de Montpellier, 34090 Montpellier, France
| | - C Azevedo
- Université de Montpellier, laboratoire d'informatique, de robotique et de microélectronique de Montpellier, 34090 Montpellier, France; Institut national de recherche en informatique et en automatique, LIRMM, université de Montpellier, 34090 Montpellier, France
| | - D Mottet
- Movement to Health (M2H), Euromov, université de Montpellier, Montpellier, France
| | - P Fraisse
- Université de Montpellier, laboratoire d'informatique, de robotique et de microélectronique de Montpellier, 34090 Montpellier, France
| | - E Pastor
- CCAS de Lattes, 34970 Lattes, France
| | - J Mercier
- CHRU de Montpellier, U1046 Inserm, université Montpellier 1, 34090 Montpellier, France
| | - R Bourret
- CHRU de Montpellier, Direction générale, 34090 Montpellier, France
| | | | - J Pélissier
- Movement to Health (M2H), Euromov, université de Montpellier, Montpellier, France; CHU de Nîmes, hôpital Carémeau et du Grau du Roi, département de médecine physique et de réadaptation, 30029 Nîmes, France
| | - B Bardy
- Movement to Health (M2H), Euromov, université de Montpellier, Montpellier, France
| | - C Herisson
- CHRU de Montpellier, département de médecine physique et de réadaptation, 34090 Montpellier, France; Movement to Health (M2H), Euromov, université de Montpellier, Montpellier, France
| | - A Dupeyron
- Movement to Health (M2H), Euromov, université de Montpellier, Montpellier, France; CHU de Nîmes, hôpital Carémeau et du Grau du Roi, département de médecine physique et de réadaptation, 30029 Nîmes, France; CHU Carémeau, CEDMH, 30029 Nîmes, France
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14
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Lebrun R, Jenkins A, Dussaux A, Locatelli N, Tsunegi S, Grimaldi E, Kubota H, Bortolotti P, Yakushiji K, Grollier J, Fukushima A, Yuasa S, Cros V. Understanding of Phase Noise Squeezing Under Fractional Synchronization of a Nonlinear Spin Transfer Vortex Oscillator. Phys Rev Lett 2015; 115:017201. [PMID: 26182117 DOI: 10.1103/physrevlett.115.017201] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Indexed: 06/04/2023]
Abstract
We investigate experimentally the synchronization of vortex based spin transfer nano-oscillators to an external rf current whose frequency is at multiple integers, as well as at an integer fraction, of the oscillator frequency. Through a theoretical study of the locking mechanism, we highlight the crucial role of both the symmetries of the spin torques and the nonlinear properties of the oscillator in understanding the phase locking mechanism. In the locking regime, we report a phase noise reduction down to -90 dBc/Hz at 1 kHz offset frequency. Our demonstration that the phase noise of these nanoscale nonlinear oscillators can be tuned and eventually lessened, represents a key achievement for targeted radio frequency applications using spin torque devices.
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Affiliation(s)
- R Lebrun
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud, 1 Avenue Fresnel, 91767 Palaiseau, France
| | - A Jenkins
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud, 1 Avenue Fresnel, 91767 Palaiseau, France
| | - A Dussaux
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud, 1 Avenue Fresnel, 91767 Palaiseau, France
| | - N Locatelli
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud, 1 Avenue Fresnel, 91767 Palaiseau, France
| | - S Tsunegi
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud, 1 Avenue Fresnel, 91767 Palaiseau, France
- National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan
| | - E Grimaldi
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud, 1 Avenue Fresnel, 91767 Palaiseau, France
| | - H Kubota
- National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan
| | - P Bortolotti
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud, 1 Avenue Fresnel, 91767 Palaiseau, France
| | - K Yakushiji
- National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan
| | - J Grollier
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud, 1 Avenue Fresnel, 91767 Palaiseau, France
| | - A Fukushima
- National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan
| | - S Yuasa
- National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568, Japan
| | - V Cros
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud, 1 Avenue Fresnel, 91767 Palaiseau, France
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15
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Hamadeh A, d'Allivy Kelly O, Hahn C, Meley H, Bernard R, Molpeceres AH, Naletov VV, Viret M, Anane A, Cros V, Demokritov SO, Prieto JL, Muñoz M, de Loubens G, Klein O. Full control of the spin-wave damping in a magnetic insulator using spin-orbit torque. Phys Rev Lett 2014; 113:197203. [PMID: 25415921 DOI: 10.1103/physrevlett.113.197203] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Indexed: 06/04/2023]
Abstract
It is demonstrated that the threshold current for damping compensation can be reached in a 5 μm diameter YIG(20 nm)|Pt(7 nm) disk. The demonstration rests upon the measurement of the ferromagnetic resonance linewidth as a function of I(dc) using a magnetic resonance force microscope (MRFM). It is shown that the magnetic losses of spin-wave modes existing in the magnetic insulator can be reduced or enhanced by at least a factor of 5 depending on the polarity and intensity of an in-plane dc current I(dc) flowing through the adjacent normal metal with strong spin-orbit interaction. Complete compensation of the damping of the fundamental mode by spin-orbit torque is reached for a current density of ∼3×10(11) A·m(-2), in agreement with theoretical predictions. At this critical threshold the MRFM detects a small change of static magnetization, a behavior consistent with the onset of an auto-oscillation regime.
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Affiliation(s)
- A Hamadeh
- Service de Physique de l'État Condensé (CNRS URA 2464), CEA Saclay, 91191 Gif-sur-Yvette, France
| | - O d'Allivy Kelly
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud 11, 1 avenue Fresnel, 91767 Palaiseau, France
| | - C Hahn
- Service de Physique de l'État Condensé (CNRS URA 2464), CEA Saclay, 91191 Gif-sur-Yvette, France
| | - H Meley
- Service de Physique de l'État Condensé (CNRS URA 2464), CEA Saclay, 91191 Gif-sur-Yvette, France
| | - R Bernard
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud 11, 1 avenue Fresnel, 91767 Palaiseau, France
| | - A H Molpeceres
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud 11, 1 avenue Fresnel, 91767 Palaiseau, France
| | - V V Naletov
- Service de Physique de l'État Condensé (CNRS URA 2464), CEA Saclay, 91191 Gif-sur-Yvette, France and Unité Mixte de Physique CNRS/Thales and Université Paris Sud 11, 1 avenue Fresnel, 91767 Palaiseau, France and Institute of Physics, Kazan Federal University, Kazan 420008, Russian Federation
| | - M Viret
- Service de Physique de l'État Condensé (CNRS URA 2464), CEA Saclay, 91191 Gif-sur-Yvette, France
| | - A Anane
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud 11, 1 avenue Fresnel, 91767 Palaiseau, France
| | - V Cros
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud 11, 1 avenue Fresnel, 91767 Palaiseau, France
| | - S O Demokritov
- Department of Physics, University of Muenster, 48149 Muenster, Germany and Institute of Metal Physics, Ural Division of RAS, Yekaterinburg 620041, Russia
| | - J L Prieto
- Instituto de Sistemas Optoelectrónicos y Microtecnología (UPM), Madrid 28040, Spain
| | - M Muñoz
- Instituto de Microelectrónica de Madrid (CNM, CSIC), Madrid 28760, Spain
| | - G de Loubens
- Service de Physique de l'État Condensé (CNRS URA 2464), CEA Saclay, 91191 Gif-sur-Yvette, France
| | - O Klein
- Service de Physique de l'État Condensé (CNRS URA 2464), CEA Saclay, 91191 Gif-sur-Yvette, France and SPINTEC, UMR CEA/CNRS/UJF-Grenoble 1/Grenoble-INP, INAC, 38054 Grenoble, France
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16
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Hamadeh A, Locatelli N, Naletov VV, Lebrun R, de Loubens G, Grollier J, Klein O, Cros V. Origin of spectral purity and tuning sensitivity in a spin transfer vortex nano-oscillator. Phys Rev Lett 2014; 112:257201. [PMID: 25014825 DOI: 10.1103/physrevlett.112.257201] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Indexed: 06/03/2023]
Abstract
We investigate the microwave characteristics of a spin transfer nano-oscillator (STNO) based on coupled vortices as a function of the perpendicular magnetic field H(⊥). Interestingly, we find that our vortex-based oscillator is quasi-isochronous independently of H(⊥) and for a dc current ranging between 18 and 25 mA. It means that the severe nonlinear broadening usually observed in STNOs can be suppressed on a broad range of bias. Still, the generation linewidth displays strong variations on H(⊥) (from 40 kHz to 1 MHz), while the frequency tunability in current remains almost constant (7 MHz/mA). This demonstrates that isochronicity does not necessarily imply a loss of frequency tunability, which is here governed by the current induced Oersted field. It is not sufficient either to achieve the highest spectral purity in the full range of H(⊥). We show that the observed linewidth broadenings are due to the excited mode interacting with a lower energy overdamped mode, which occurs at the successive crossings between harmonics of these two modes. These findings open new possibilities for the design of STNOs and the optimization of their performance.
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Affiliation(s)
- A Hamadeh
- Service de Physique de l'État Condensé (CNRS URA 2464), CEA Saclay, 91191 Gif-sur-Yvette, France
| | - N Locatelli
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud 11, 1 Avenue Fresnel, 91767 Palaiseau, France
| | - V V Naletov
- Service de Physique de l'État Condensé (CNRS URA 2464), CEA Saclay, 91191 Gif-sur-Yvette, France and Unité Mixte de Physique CNRS/Thales and Université Paris Sud 11, 1 Avenue Fresnel, 91767 Palaiseau, France and Institute of Physics, Kazan Federal University, Kazan 420008, Russian Federation
| | - R Lebrun
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud 11, 1 Avenue Fresnel, 91767 Palaiseau, France
| | - G de Loubens
- Service de Physique de l'État Condensé (CNRS URA 2464), CEA Saclay, 91191 Gif-sur-Yvette, France
| | - J Grollier
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud 11, 1 Avenue Fresnel, 91767 Palaiseau, France
| | - O Klein
- Service de Physique de l'État Condensé (CNRS URA 2464), CEA Saclay, 91191 Gif-sur-Yvette, France and SPINTEC, UMR CEA/CNRS/UJF-Grenoble 1/Grenoble-INP, INAC, 38054 Grenoble, France
| | - V Cros
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud 11, 1 Avenue Fresnel, 91767 Palaiseau, France
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Abstract
The discovery of the spin-torque effect has made magnetic nanodevices realistic candidates for active elements of memory devices and applications. Magnetoresistive effects allow the read-out of increasingly small magnetic bits, and the spin torque provides an efficient tool to manipulate - precisely, rapidly and at low energy cost - the magnetic state, which is in turn the central information medium of spintronic devices. By keeping the same magnetic stack, but by tuning a device's shape and bias conditions, the spin torque can be engineered to build a variety of advanced magnetic nanodevices. Here we show that by assembling these nanodevices as building blocks with different functionalities, novel types of computing architecture can be envisaged. We focus in particular on recent concepts such as magnonics and spintronic neural networks.
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Affiliation(s)
- N Locatelli
- Unité Mixte de Physique CNRS/Thales, 1 Avenue Augustin Fresnel, Campus de l'Ecole Polytechnique, 91767 Palaiseau, France, and Université Paris-Sud, 91405 Orsay, France
| | - V Cros
- Unité Mixte de Physique CNRS/Thales, 1 Avenue Augustin Fresnel, Campus de l'Ecole Polytechnique, 91767 Palaiseau, France, and Université Paris-Sud, 91405 Orsay, France
| | - J Grollier
- Unité Mixte de Physique CNRS/Thales, 1 Avenue Augustin Fresnel, Campus de l'Ecole Polytechnique, 91767 Palaiseau, France, and Université Paris-Sud, 91405 Orsay, France
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18
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Sampaio J, Cros V, Rohart S, Thiaville A, Fert A. Nucleation, stability and current-induced motion of isolated magnetic skyrmions in nanostructures. Nat Nanotechnol 2013; 8:839-44. [PMID: 24162000 DOI: 10.1038/nnano.2013.210] [Citation(s) in RCA: 371] [Impact Index Per Article: 33.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Accepted: 09/16/2013] [Indexed: 05/13/2023]
Abstract
Magnetic skyrmions are topologically stable spin configurations, which usually originate from chiral interactions known as Dzyaloshinskii-Moriya interactions. Skyrmion lattices were initially observed in bulk non-centrosymmetric crystals, but have more recently been noted in ultrathin films, where their existence is explained by interfacial Dzyaloshinskii-Moriya interactions induced by the proximity to an adjacent layer with strong spin-orbit coupling. Skyrmions are promising candidates as information carriers for future information-processing devices due to their small size (down to a few nanometres) and to the very small current densities needed to displace skyrmion lattices. However, any practical application will probably require the creation, manipulation and detection of isolated skyrmions in magnetic thin-film nanostructures. Here, we demonstrate by numerical investigations that an isolated skyrmion can be a stable configuration in a nanostructure, can be locally nucleated by injection of spin-polarized current, and can be displaced by current-induced spin torques, even in the presence of large defects.
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Affiliation(s)
- J Sampaio
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud, Palaiseau, France
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19
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Uhlíř V, Vogel J, Rougemaille N, Fruchart O, Ishaque Z, Cros V, Camarero J, Cezar JC, Sirotti F, Pizzini S. Current-induced domain wall motion and magnetization dynamics in CoFeB/Cu/Co nanostripes. J Phys Condens Matter 2012; 24:024213. [PMID: 22173430 DOI: 10.1088/0953-8984/24/2/024213] [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] [Indexed: 05/31/2023]
Abstract
Current-induced domain wall motion and magnetization dynamics in the CoFeB layer of CoFeB/Cu/Co nanostripes were studied using photoemission electron microscopy combined with x-ray magnetic circular dichroism (XMCD-PEEM). Quasi-static measurements show that current-induced domain wall motion in the CoFeB layer is similar to the one observed in the NiFe layer of NiFe/Cu/Co trilayers, although the threshold current densities for domain wall depinning are lower. Time-resolved XMCD-PEEM measurements are used as an efficient probe of domain wall depinning statistics. They also reveal that, during the application of current pulses, the CoFeB magnetization rotates in the direction transverse to the nanostripe. The corresponding tilt angles have been quantified and compared to analytical and micromagnetic calculations, highlighting the influence of magnetostatic interactions between the two magnetic layers on the magnetization rotation.
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Affiliation(s)
- V Uhlíř
- Institut Néel, CNRS and UJF, BP 166, 38042 Grenoble Cedex 9, France
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20
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Dussaux A, Georges B, Grollier J, Cros V, Khvalkovskiy AV, Fukushima A, Konoto M, Kubota H, Yakushiji K, Yuasa S, Zvezdin KA, Ando K, Fert A. Large microwave generation from current-driven magnetic vortex oscillators in magnetic tunnel junctions. Nat Commun 2010; 1:8. [PMID: 20975671 DOI: 10.1038/ncomms1006] [Citation(s) in RCA: 300] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2010] [Accepted: 03/04/2010] [Indexed: 11/09/2022] Open
Abstract
Spin-polarized current can excite the magnetization of a ferromagnet through the transfer of spin angular momentum to the local spin system. This pure spin-related transport phenomenon leads to alluring possibilities for the achievement of a nanometer scale, complementary metal oxide semiconductor-compatible, tunable microwave generator that operates at low bias for future wireless communication applications. Microwave emission generated by the persistent motion of magnetic vortices induced by a spin-transfer effect seems to be a unique manner to reach appropriate spectral linewidth. However, in metallic systems, in which such vortex oscillations have been observed, the resulting microwave power is much too small. In this study, we present experimental evidence of spin-transfer-induced vortex precession in MgO-based magnetic tunnel junctions, with an emitted power that is at least one order of magnitude stronger and with similar spectral quality. More importantly and in contrast to other spin-transfer excitations, the thorough comparison between experimental results and analytical predictions provides a clear textbook illustration of the mechanism of spin-transfer-induced vortex precession.
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Affiliation(s)
- A Dussaux
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud 11, Palaiseau, France
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21
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Copie O, Rode K, Mattana R, Bibes M, Cros V, Herranz G, Anane A, Ranchal R, Jacquet E, Bouzehouane K, Arrio MA, Bencok P, Brookes NB, Petroff F, Barthélémy A. Structural and magnetic properties of Co-doped (La,Sr)TiO(3) epitaxial thin films probed using x-ray magnetic circular dichroism. J Phys Condens Matter 2009; 21:406001. [PMID: 21832426 DOI: 10.1088/0953-8984/21/40/406001] [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] [Indexed: 05/31/2023]
Abstract
We report a study of Co-doped La(0.37)Sr(0.63)TiO(3-δ) thin films grown by pulsed laser deposition in various oxygen pressure conditions. X-ray absorption spectroscopy and magnetic circular dichroism measurements at the Co L(2,3) edges reveal that the cobalt mainly substitutes for the titanium and is in an ionic state. Nevertheless, in some films, indications of additional cobalt metallic impurities were found, suggesting that the intrinsic character of this magnetic system remains questionable.
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Affiliation(s)
- O Copie
- Unité Mixte de Physique CNRS/Thales, Campus de l'Ecole Polytechnique, 1 Avenue A Fresnel, 91767 Palaiseau, France and Université Paris-Sud 11, 91405 Orsay, France
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22
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Ruotolo A, Cros V, Georges B, Dussaux A, Grollier J, Deranlot C, Guillemet R, Bouzehouane K, Fusil S, Fert A. Phase-locking of magnetic vortices mediated by antivortices. Nat Nanotechnol 2009; 4:528-532. [PMID: 19662017 DOI: 10.1038/nnano.2009.143] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2009] [Accepted: 05/05/2009] [Indexed: 05/28/2023]
Abstract
Synchronized spin-valve oscillators may lead to nanosized microwave generators that do not require discrete elements such as capacitors or inductors. Uniformly magnetized oscillators have been synchronized, but offer low power. Gyrating magnetic vortices offer greater power, but vortex synchronization has yet to be demonstrated. Here we find that vortices can interact with each other through the mediation of antivortices, leading to synchronization when they are closely spaced. The synchronization does not require a magnetic field, making the system attractive for electronic device integration. Also, because each vortex is a topological soliton, this work presents a model experimental system for the study of interacting solitons.
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Affiliation(s)
- A Ruotolo
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud 11, Palaiseau, France.
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23
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Béa H, Dupé B, Fusil S, Mattana R, Jacquet E, Warot-Fonrose B, Wilhelm F, Rogalev A, Petit S, Cros V, Anane A, Petroff F, Bouzehouane K, Geneste G, Dkhil B, Lisenkov S, Ponomareva I, Bellaiche L, Bibes M, Barthélémy A. Evidence for room-temperature multiferroicity in a compound with a giant axial ratio. Phys Rev Lett 2009; 102:217603. [PMID: 19519136 DOI: 10.1103/physrevlett.102.217603] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2008] [Indexed: 05/12/2023]
Abstract
In the search for multiferroic materials magnetic compounds with a strongly elongated unit-cell (large axial ratio c/a) have been scrutinized intensely. However, none was hitherto proven to have a switchable polarization, an essential feature of ferroelectrics. Here, we provide evidence for the epitaxial stabilization of a monoclinic phase of BiFeO3 with a giant axial ratio (c/a=1.23) that is both ferroelectric and magnetic at room temperature. Surprisingly, and in contrast with previous theoretical predictions, the polarization does not increase dramatically with c/a. We discuss our results in terms of the competition between polar and antiferrodistortive instabilities and give perspectives for engineering multiferroic phases.
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Affiliation(s)
- H Béa
- Unité Mixte de Physique CNRS/Thales, Campus de l'Ecole Polytechnique, 1 Av. A. Fresnel, 91767 Palaiseau, France
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24
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Khvalkovskiy AV, Zvezdin KA, Gorbunov YV, Cros V, Grollier J, Fert A, Zvezdin AK. High Domain Wall Velocities due to Spin Currents Perpendicular to the Plane. Phys Rev Lett 2009; 102:067206. [PMID: 19257631 DOI: 10.1103/physrevlett.102.067206] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2008] [Revised: 01/30/2009] [Indexed: 05/27/2023]
Abstract
We consider long and narrow spin valves composed of a first magnetic layer with a single domain wall (DW), a normal metal spacer, and a second magnetic layer that is a planar or a perpendicular polarizer. For these structures, we study numerically DW dynamics taking into account the spin torques due to the perpendicular spin currents. We obtain high DW velocities: 5 m/s for planar polarizer and 80 m/s for perpendicular polarizer for I=0.01 mA. These values are much larger than those predicted and observed for DW motion due to the in-plane spin currents. The ratio of the magnitudes of the torques, which generate the DW motion in the respective cases, is responsible for these large differences.
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Affiliation(s)
- A V Khvalkovskiy
- A. M. Prokhorov General Physics Institute of RAS, 119991 Moscow, Russia.
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25
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Georges B, Grollier J, Darques M, Cros V, Deranlot C, Marcilhac B, Faini G, Fert A. Coupling efficiency for phase locking of a spin transfer nano-oscillator to a microwave current. Phys Rev Lett 2008; 101:017201. [PMID: 18764148 DOI: 10.1103/physrevlett.101.017201] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2008] [Indexed: 05/26/2023]
Abstract
The phase locking behavior of spin transfer nano-oscillators (STNOs) to an external microwave signal is experimentally studied as a function of the STNO intrinsic parameters. We extract the coupling strength from our data using the derived phase dynamics of a forced STNO. The predicted trends on the coupling strength for phase locking as a function of intrinsic features of the oscillators, i.e., power, linewidth, agility in current, are central to optimize the emitted power in arrays of mutually coupled STNOs.
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Affiliation(s)
- B Georges
- Unité Mixte de Physique CNRS/Thales and Université Paris Sud 11, RD 128, 91767 Palaiseau, France
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Marangolo M, Gustavsson F, Eddrief M, Sainctavit P, Etgens VH, Cros V, Petroff F, George JM, Bencok P, Brookes NB. Magnetism of the Fe/ZnSe(001) interface. Phys Rev Lett 2002; 88:217202. [PMID: 12059497 DOI: 10.1103/physrevlett.88.217202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2001] [Indexed: 05/23/2023]
Abstract
The magnetism of epitaxial ultrathin films of Fe on ZnSe(001) has been investigated by x-ray magnetic circular dichroism down to the submonolayer regime. In contrast to other metallic ferromagnet/semiconductor interfaces, no reduction of the Fe magnetic moment was found at the Fe/ZnSe(001) interface. Furthermore, a significant enhancement of the Fe magnetic moment compared to the bulk value was observed for coverages up to one monolayer in agreement with theoretical predictions. We also demonstrate that the magnetic properties of the Fe/ZnSe(001) interface remain stable against thermal annealing up to 300 degrees C, a prerequisite for the future development of efficient spintronics devices.
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Affiliation(s)
- M Marangolo
- LMCP, Laboratoire de Minéralogie-Cristallographie, Universités Paris 6 et Paris 7, CNRS UMR 7590, 4 Place Jussieu, 75252 Paris Cedex 05, France
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27
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Barthélémy A, Cros V, Duvail J, Fert A, Morel R, Parent F, Petroff F, Steren L. Giant magnetoresistance in magnetic nanostructures. ACTA ACUST UNITED AC 1995. [DOI: 10.1016/0965-9773(95)00045-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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