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Zakeri K. Magnonic crystals: towards terahertz frequencies. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2020; 32:363001. [PMID: 32289765 DOI: 10.1088/1361-648x/ab88f2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2019] [Accepted: 04/14/2020] [Indexed: 06/11/2023]
Abstract
This topical review presents an overview of the recent experimental and theoretical attempts on designing magnonic crystals for operation at different frequencies. The focus is put on the microscopic physical mechanisms involved in the formation of the magnonic band structure, allowed as well as forbidden magnon states in various systems, including ultrathin films, multilayers and artificial magnetic structures. The essential criteria for the formation of magnonic bandgaps in different frequency regimes are explained in connection with the magnon dynamics in such structures. The possibility of designing small-size magnonic crystals for operation at ultrahigh frequencies (terahertz and sub-terahertz regime) is discussed. Recently discovered magnonic crystals based on topological defects and using periodic Dzyaloshinskii-Moriya interaction, are outlined. Different types of magnonic crystals, capable of operation at different frequency regimes, are put within a rather unified picture.
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Affiliation(s)
- Khalil Zakeri
- Heisenberg Spin-dynamics Group, Physikalisches Institut, Karlsruhe Institute of Technology, Wolfgang-Gaede-Str. 1, D-76131 Karlsruhe, Germany
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2
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Kim SK, Tserkovnyak Y. Chiral Edge Mode in the Coupled Dynamics of Magnetic Solitons in a Honeycomb Lattice. PHYSICAL REVIEW LETTERS 2017; 119:077204. [PMID: 28949656 DOI: 10.1103/physrevlett.119.077204] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Indexed: 06/07/2023]
Abstract
Motivated by a recent experimental demonstration of a chiral edge mode in an array of spinning gyroscopes, we theoretically study the coupled gyration modes of topological magnetic solitons, vortices and magnetic bubbles, arranged as a honeycomb lattice. The soliton lattice under suitable conditions is shown to support a chiral edge mode like its mechanical analogue, the existence of which can be understood by mapping the system to the Haldane model for an electronic system. The direction of the chiral edge mode is associated with the topological charge of the constituent solitons, which can be manipulated by an external field or by an electric-current pulse. The direction can also be controlled by distorting the honeycomb lattice. Our results indicate that the lattices of magnetic solitons can serve as reprogrammable topological metamaterials.
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Affiliation(s)
- Se Kwon Kim
- Department of Physics and Astronomy, University of California, Los Angeles, California 90095, USA
| | - Yaroslav Tserkovnyak
- Department of Physics and Astronomy, University of California, Los Angeles, California 90095, USA
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3
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Li Y, de Milly X, Abreu Araujo F, Klein O, Cros V, Grollier J, de Loubens G. Probing Phase Coupling Between Two Spin-Torque Nano-Oscillators with an External Source. PHYSICAL REVIEW LETTERS 2017; 118:247202. [PMID: 28665656 DOI: 10.1103/physrevlett.118.247202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Indexed: 06/07/2023]
Abstract
Phase coupling between auto-oscillators is central for achieving coherent responses such as synchronization. Here we present an experimental approach to probe it in the case of two dipolarly coupled spin-torque vortex nano-oscillators using an external microwave field. By phase locking one oscillator to the external source, we observe frequency pulling on the second oscillator. From coupled phase equations we show analytically that this frequency pulling results from concerted actions of oscillator-oscillator and source-oscillator couplings. The analysis allows us to determine the strength and phase shift of coupling between two oscillators, yielding important information for the implementation of large interacting oscillator networks.
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Affiliation(s)
- Yi Li
- Service de Physique de l'État Condensé, CEA, CNRS, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
| | - Xavier de Milly
- Service de Physique de l'État Condensé, CEA, CNRS, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
| | - Flavio Abreu Araujo
- Unité Mixte de Physique CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, 91767 Palaiseau, France
| | - Olivier Klein
- SPINTEC, Université Grenoble Alpes, CEA, CNRS, 38000 Grenoble, France
| | - Vincent Cros
- Unité Mixte de Physique CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, 91767 Palaiseau, France
| | - Julie Grollier
- Unité Mixte de Physique CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, 91767 Palaiseau, France
| | - Grégoire de Loubens
- Service de Physique de l'État Condensé, CEA, CNRS, Université Paris-Saclay, 91191 Gif-sur-Yvette, France
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4
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Kim J, Yang J, Cho YJ, Kim B, Kim SK. Coupled gyration modes in one-dimensional skyrmion arrays in thin-film nanostrips as new type of information carrier. Sci Rep 2017; 7:45185. [PMID: 28327624 PMCID: PMC5361123 DOI: 10.1038/srep45185] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 02/20/2017] [Indexed: 11/24/2022] Open
Abstract
We report on a micromagnetic numerical simulation study of dynamic coupling between neighboring skyrmions periodically arranged in narrow-width nanostrips. We explored the coupled gyration modes and their characteristic dispersions in terms of the interdistance between the neighboring skyrmions. The application of perpendicular magnetic fields allows for the control and modification of the dispersion of the coupled gyration modes. The coupled gyration modes of individual skyrmions might provide a new type of information carrier in narrow-width straight and curved nanostrips, as driven by magnetic interactions in such continuous thin films.
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Affiliation(s)
- Junhoe Kim
- National Creative Research Initiative Center for Spin Dynamics and Spin-Wave Devices, Nanospinics Laboratory, Research Institute of Advanced Materials, Department of Materials Science and Engineering, Seoul National University, Seoul 151-744, Republic of Korea
| | - Jaehak Yang
- National Creative Research Initiative Center for Spin Dynamics and Spin-Wave Devices, Nanospinics Laboratory, Research Institute of Advanced Materials, Department of Materials Science and Engineering, Seoul National University, Seoul 151-744, Republic of Korea
| | - Young-Jun Cho
- National Creative Research Initiative Center for Spin Dynamics and Spin-Wave Devices, Nanospinics Laboratory, Research Institute of Advanced Materials, Department of Materials Science and Engineering, Seoul National University, Seoul 151-744, Republic of Korea
| | - Bosung Kim
- National Creative Research Initiative Center for Spin Dynamics and Spin-Wave Devices, Nanospinics Laboratory, Research Institute of Advanced Materials, Department of Materials Science and Engineering, Seoul National University, Seoul 151-744, Republic of Korea
| | - Sang-Koog Kim
- National Creative Research Initiative Center for Spin Dynamics and Spin-Wave Devices, Nanospinics Laboratory, Research Institute of Advanced Materials, Department of Materials Science and Engineering, Seoul National University, Seoul 151-744, Republic of Korea
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5
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Bukin N, McKeever C, Burgos-Parra E, Keatley PS, Hicken RJ, Ogrin FY, Beutier G, Dupraz M, Popescu H, Jaouen N, Yakhou-Harris F, Cavill SA, van der Laan G. Time-resolved imaging of magnetic vortex dynamics using holography with extended reference autocorrelation by linear differential operator. Sci Rep 2016; 6:36307. [PMID: 27796347 PMCID: PMC5087091 DOI: 10.1038/srep36307] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 10/13/2016] [Indexed: 11/24/2022] Open
Abstract
The magnetisation dynamics of the vortex core and Landau pattern of magnetic thin-film elements has been studied using holography with extended reference autocorrelation by linear differential operator (HERALDO). Here we present the first time-resolved x-ray measurements using this technique and investigate the structure and dynamics of the domain walls after excitation with nanosecond pulsed magnetic fields. It is shown that the average magnetisation of the domain walls has a perpendicular component that can change dynamically depending on the parameters of the pulsed excitation. In particular, we demonstrate the formation of wave bullet-like excitations, which are generated in the domain walls and can propagate inside them during the cyclic motion of the vortex core. Based on numerical simulations we also show that, besides the core, there are four singularities formed at the corners of the pattern. The polarisation of these singularities has a direct relation to the vortex core, and can be switched dynamically by the wave bullets excited with a magnetic pulse of specific parameters. The subsequent dynamics of the Landau pattern is dependent on the particular configuration of the polarisations of the core and the singularities.
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Affiliation(s)
- N. Bukin
- School of Physics and Astronomy, University of Exeter, Exeter, EX4 4QL, United Kingdom
| | - C. McKeever
- School of Physics and Astronomy, University of Exeter, Exeter, EX4 4QL, United Kingdom
| | - E. Burgos-Parra
- School of Physics and Astronomy, University of Exeter, Exeter, EX4 4QL, United Kingdom
| | - P. S. Keatley
- School of Physics and Astronomy, University of Exeter, Exeter, EX4 4QL, United Kingdom
| | - R. J. Hicken
- School of Physics and Astronomy, University of Exeter, Exeter, EX4 4QL, United Kingdom
| | - F. Y. Ogrin
- School of Physics and Astronomy, University of Exeter, Exeter, EX4 4QL, United Kingdom
| | | | - M. Dupraz
- Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - H. Popescu
- SOLEIL Synchrotron, 91192 Saint-Aubin, France
| | - N. Jaouen
- SOLEIL Synchrotron, 91192 Saint-Aubin, France
| | - F. Yakhou-Harris
- European Synchrotron Radiation Facility, F-38043 Grenoble Cedex 9, France
| | - S. A. Cavill
- Department of Physics, University of York, York, YO10 5DD, United Kingdom
| | - G. van der Laan
- Diamond Light Source, Harwell Science and innovation Campus, Didcot, Oxfordshire, OX11 0DE, United Kingdom
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Haldar A, Kumar D, Adeyeye AO. A reconfigurable waveguide for energy-efficient transmission and local manipulation of information in a nanomagnetic device. NATURE NANOTECHNOLOGY 2016; 11:437-43. [PMID: 26828846 DOI: 10.1038/nnano.2015.332] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Accepted: 12/15/2015] [Indexed: 05/26/2023]
Abstract
Spin-wave-based devices promise to usher in an era of low-power computing where information is carried by the precession of the electrons' spin instead of dissipative translation of their charge. This potential is, however, undermined by the need for a bias magnetic field, which must remain powered on to maintain an anisotropic device characteristic. Here, we propose a reconfigurable waveguide design that can transmit and locally manipulate spin waves without the need for any external bias field once initialized. We experimentally demonstrate the transmission of spin waves in straight as well as curved waveguides without a bias field, which has been elusive so far. Furthermore, we experimentally show a binary gating of the spin-wave signal by controlled switching of the magnetization, locally, in the waveguide. The results have potential implications in high-density integration and energy-efficient operation of nanomagnetic devices at room temperature.
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Affiliation(s)
- Arabinda Haldar
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576, Singapore
| | - Dheeraj Kumar
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576, Singapore
| | - Adekunle Olusola Adeyeye
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576, Singapore
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7
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Hänze M, Adolff CF, Schulte B, Möller J, Weigand M, Meier G. Collective modes in three-dimensional magnonic vortex crystals. Sci Rep 2016; 6:22402. [PMID: 26932833 PMCID: PMC4773813 DOI: 10.1038/srep22402] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 02/11/2016] [Indexed: 11/29/2022] Open
Abstract
Collective modes in three-dimensional crystals of stacked permalloy disks with magnetic vortices are investigated by ferromagnetic resonance spectroscopy and scanning transmission X-ray microscopy. The size of the arrangements is increased step by step to identify the different contributions to the interaction between the vortices. These contributions are the key requirement to understand complex dynamics of three dimensional vortex crystals. Both vertical and horizontal coupling determine the collective modes. In-plane dipoles strongly influence the interaction between the disks in the stacks and lead to polarity-dependent resonance frequencies. Weaker contributions discern arrangements with different polarities and circularities that result from the lateral coupling of the stacks and the interaction of the core regions inside a stack. All three contributions are identified in the experiments and are explained in a rigid particle model.
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Affiliation(s)
- Max Hänze
- Institut für Angewandte Physik und Zentrum für Mikrostrukturforschung, Universität Hamburg, 20355 Hamburg, Germany
| | - Christian F. Adolff
- Institut für Angewandte Physik und Zentrum für Mikrostrukturforschung, Universität Hamburg, 20355 Hamburg, Germany
| | - Benedikt Schulte
- Institut für Angewandte Physik und Zentrum für Mikrostrukturforschung, Universität Hamburg, 20355 Hamburg, Germany
| | - Jan Möller
- Institut für Angewandte Physik und Zentrum für Mikrostrukturforschung, Universität Hamburg, 20355 Hamburg, Germany
| | - Markus Weigand
- Max-Planck Institute for Intelligent Systems, Heisenbergstr. 3, 70569 Stuttgart, Germany
| | - Guido Meier
- Institut für Angewandte Physik und Zentrum für Mikrostrukturforschung, Universität Hamburg, 20355 Hamburg, Germany
- Max-Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
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8
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Cui X, Hu S, Hidegara M, Yakata S, Kimura T. Sensitive detection of vortex-core resonance using amplitude-modulated magnetic field. Sci Rep 2015; 5:17922. [PMID: 26647840 PMCID: PMC4673421 DOI: 10.1038/srep17922] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 10/13/2015] [Indexed: 11/09/2022] Open
Abstract
Understanding and manipulating the dynamic properties of the magnetic vortices stabilized in patterned ferromagnetic structures are of great interest owing to the superior resonant features with the high thermal stability and their flexible tunability. So far, numerous methods for investigating the dynamic properties of the magnetic vortex have been proposed and demonstrated. However, those techniques have some regulations such as spatial resolution, experimental facility and sensitivity. Here, we develop a simple and sensitive method for investigating the vortex-core dynamics by using the electrically separated excitation and detection circuits. We demonstrate that the resonant oscillation of the magnetic vortex induced by the amplitude- modulated alternating-sign magnetic field is efficiently picked up by the lock-in detection with the modulated frequency. By extending this method, we also investigate the size dependence and the influence of the magneto-static interaction in the resonant property of the magnetic vortex.
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Affiliation(s)
- Xiaomin Cui
- Graduate School of Information Science and Electrical Engineering, Kyushu University, 744 Motooka, Fukuoka, 819-0395, Japan
| | - Shaojie Hu
- Graduate School of Information Science and Electrical Engineering, Kyushu University, 744 Motooka, Fukuoka, 819-0395, Japan
| | - Makoto Hidegara
- Department of Physics, Kyushu University, 6-10-1 Hakozaki, Fukuoka 812-8581, Japan
| | - Satoshi Yakata
- Department of Information Electronics, Fukuoka Institute of Technology, 3-30-1 Wajiro-higashi, Higashi-ku, Fukuoka, 811-0295 Japan
| | - Takashi Kimura
- Department of Physics, Kyushu University, 6-10-1 Hakozaki, Fukuoka 812-8581, Japan.,Research Center for Quantum Nano-Spin Sciences, Kyushu University, 6-10-1 Hakozaki, Fukuoka 812-8581, Japan.,CREST, Japan Science and Technology Agency, Sanbancho, Tokyo 102-0075, Japan
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Nissen D, Mitin D, Klein O, Arekapudi SSPK, Thomas S, Im MY, Fischer P, Albrecht M. Magnetic coupling of vortices in a two dimensional lattice. NANOTECHNOLOGY 2015; 26:465706. [PMID: 26511585 DOI: 10.1088/0957-4484/26/46/465706] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We investigated the magnetization reversal of magnetic vortex structures in a two-dimensional lattice. The structures were formed by permalloy (Py) film deposition onto large arrays of self assembled spherical SiO(2)-particles with a diameter of 330 nm. We present the dependence of the nucleation and annihilation field of the vortex structures as a function of the Py layer thickness(aspect ratio) and temperature. By increasing the Py thickness up to 90 nm or alternatively by lowering the temperature the vortex structure becomes more stable as expected. However, the increase of the Py thickness results in the onset of strong exchange coupling between neighboring Py caps due to the emergence of Py bridges connecting them. In particular, we studied the influence of magnetic coupling locally by in-field scanning magne to-resistive microscopy and full-field magnetic soft x-ray microscopy, revealing a domain-like nucleation process of vortex states, which arises via domain wall propagation due to exchange coupling of the closely packed structures. By analyzing the rotation sense of the reversed areas, large connected domains are present with the same circulation sense. Furthermore, the lateral core displacements when an in-plane field is applied were investigated, revealing spatially enlarged vortex cores and a broader distribution with increasing Py layer thickness. In addition, the presence of some mixed states, vortices and c-states, is indicated for the array with the thickest Py layer.
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Kruglyak VV, Gorobets OY, Gorobets YI, Kuchko AN. Magnetization boundary conditions at a ferromagnetic interface of finite thickness. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2014; 26:406001. [PMID: 25219663 DOI: 10.1088/0953-8984/26/40/406001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We develop a systematic approach to derive boundary conditions at an interface between two ferromagnetic materials in the continuous medium approximation. The approach treats the interface as a two-sublattice material, although the final equations connect magnetizations outside of the interface and therefore do not explicitly depend on its structure. Instead, the boundary conditions are defined in terms of some average properties of the interface, which may also have a finite thickness. In addition to the interface anisotropy and symmetric exchange coupling, this approach allows us to take into account coupling resulting from inversion symmetry breaking in the vicinity of the interface, such as the Dzyaloshinskii-Moriya antisymmetric exchange interaction. In the case of negligible interface anisotropy and Dzyaloshinskii-Moriya exchange parameters, the derived boundary conditions represent a generalization of those proposed earlier by Barnaś and Mills and are therefore named 'generalized Barnaś-Mills boundary conditions'. We demonstrate how one could use the boundary conditions to extract parameters of the interface via fitting of appropriate experimental data. The developed theory could be applied to modeling of both linear and non-linear spin waves, including exchange, dipole-exchange, magnetostatic, and retarded modes, as well as to calculations of non-uniform equilibrium micromagnetic configurations near the interface, with a direct impact on the research in magnonics and micromagnetism.
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Affiliation(s)
- V V Kruglyak
- School of Physics, University of Exeter, Stocker road, Exeter, EX4 4QL, UK
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Higher order vortex gyrotropic modes in circular ferromagnetic nanodots. Sci Rep 2014; 4:4796. [PMID: 24762659 PMCID: PMC3999443 DOI: 10.1038/srep04796] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Accepted: 04/08/2014] [Indexed: 11/18/2022] Open
Abstract
Magnetic vortex that consists of an in-plane curling magnetization configuration and a needle-like core region with out-of-plane magnetization is known to be the ground state of geometrically confined submicron soft magnetic elements. Here magnetodynamics of relatively thick (50–100 nm) circular Ni80Fe20 dots were probed by broadband ferromagnetic resonance in the absence of external magnetic field. Spin excitation modes related to the thickness dependent vortex core gyrotropic dynamics were detected experimentally in the gigahertz frequency range. Both analytical theory and micromagnetic simulations revealed that these exchange dominated modes are flexure oscillations of the vortex core string with n = 0,1,2 nodes along the dot thickness. The intensity of the mode with n = 1 depends significantly on both dot thickness and diameter and in some cases is higher than the one of the uniform mode with n = 0. This opens promising perspectives in the area of spin transfer torque oscillators.
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Krawczyk M, Grundler D. Review and prospects of magnonic crystals and devices with reprogrammable band structure. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2014; 26:123202. [PMID: 24599025 DOI: 10.1088/0953-8984/26/12/123202] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Research efforts addressing spin waves (magnons) in microand nanostructured ferromagnetic materials have increased tremendously in recent years. Corresponding experimental and theoretical work in magnonics faces significant challenges in that spinwave dispersion relations are highly anisotropic and different magnetic states might be realized via, for example, the magnetic field history. At the same time, these features offer novel opportunities for wave control in solids going beyond photonics and plasmonics. In this topical review we address materials with a periodic modulation of magnetic parameters that give rise to artificially tailored band structures and allow unprecedented control of spin waves. In particular, we discuss recent achievements and perspectives of reconfigurable magnonic devices for which band structures can be reprogrammed during operation. Such characteristics might be useful for multifunctional microwave and logic devices operating over a broad frequency regime on either the macroor nanoscale.
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Kumar D, Barman S, Barman A. Magnetic vortex based transistor operations. Sci Rep 2014; 4:4108. [PMID: 24531235 PMCID: PMC3925947 DOI: 10.1038/srep04108] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Accepted: 01/30/2014] [Indexed: 11/13/2022] Open
Abstract
Transistors constitute the backbone of modern day electronics. Since their advent, researchers have been seeking ways to make smaller and more efficient transistors. Here, we demonstrate a sustained amplification of magnetic vortex core gyration in coupled two and three vortices by controlling their relative core polarities. This amplification is mediated by a cascade of antivortex solitons travelling through the dynamic stray field. We further demonstrated that the amplification can be controlled by switching the polarity of the middle vortex in a three vortex sequence and the gain can be controlled by the input signal amplitude. An attempt to show fan-out operation yielded gain for one of the symmetrically placed branches which can be reversed by switching the core polarity of all the vortices in the network. The above observations promote the magnetic vortices as suitable candidates to work as stable bipolar junction transistors (BJT).
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Affiliation(s)
- D. Kumar
- Thematic Unit of Excellence on Nanodevice Technology, Department of Condensed Matter Physics and Material Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700 098, India
| | - S. Barman
- Thematic Unit of Excellence on Nanodevice Technology, Department of Condensed Matter Physics and Material Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700 098, India
| | - A. Barman
- Thematic Unit of Excellence on Nanodevice Technology, Department of Condensed Matter Physics and Material Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700 098, India
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