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Zakeri K, Ernst A. Generation and Propagation of Ultrafast Terahertz Magnons in Atomically Architectured Nanomagnets. NANO LETTERS 2024; 24:9528-9534. [PMID: 38899856 DOI: 10.1021/acs.nanolett.4c01982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/21/2024]
Abstract
Utilizing ultrafast terahertz (THz) magnons, the quanta of collective magnetic excitations, as carriers may provide a promising alternative to overcome the problems associated with electrical losses in nanoelectronic devices and circuits. However, efficient excitation of propagating coherent THz magnons in magnonic nanowaveguides is an essential requirement for the development of such devices. Here, by growing ultrathin ferromagnetic nanostructures on a reconstructed surface, we create well-ordered periodic magnetic nanostripes. We demonstrate that such atomically architectured nanowaveguides not only provide a versatile platform for an efficient generation of THz magnons but also allow for their fast propagation. Our results reveal the complex nature of the spin dynamics within such designed nanowaveguides and pave the way for designing ultrafast magnon-based logic devices with THz operation frequencies.
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Affiliation(s)
- Khalil Zakeri
- Heisenberg Spin-Dynamics Group, Physikalisches Institut, Karlsruhe Institute of Technology, Wolfgang-Gaede-Strasse 1, D-76131 Karlsruhe, Germany
| | - Arthur Ernst
- Institute for Theoretical Physics, Johannes Kepler University, Altenberger Strasse 69, A-4040 Linz, Austria
- Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany
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2
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Zakeri K, von Faber A. Giant Spin-Orbit Induced Magnon Nonreciprocity in Ultrathin Ferromagnets. PHYSICAL REVIEW LETTERS 2024; 132:126702. [PMID: 38579230 DOI: 10.1103/physrevlett.132.126702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 02/15/2024] [Indexed: 04/07/2024]
Abstract
The propagation characteristics of fermionic and bosonic quasiparticles determine the fundamental transport properties of solids and are of great technological relevance for designing logic devices. In particular, nonreciprocity, which describes that a quasiparticle flows preferably along a certain direction of a symmetry path, is an essential requirement to realize logic architectures, e.g., switches, diodes, transistors, etc. Here we introduce a mechanism, which leads to giant nonreciprocity of ultrafast terahertz magnons in ferromagnetic films with a large spin-orbit coupling. The mechanism is based on the competition between the exchange and spin-orbit scattering. We anticipate that the effect can be used to excite nonreciprocal or even unidirectional magnons in a large class of ultrathin films and nanostructures grown on substrates with a large spin-orbit coupling.
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Affiliation(s)
- Khalil Zakeri
- Heisenberg Spin-dynamics Group, Physikalisches Institut, Karlsruhe Institute of Technology, Wolfgang-Gaede-Strasse 1, D-76131 Karlsruhe, Germany
| | - Albrecht von Faber
- Heisenberg Spin-dynamics Group, Physikalisches Institut, Karlsruhe Institute of Technology, Wolfgang-Gaede-Strasse 1, D-76131 Karlsruhe, Germany
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3
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Poelchen G, Hellwig J, Peters M, Usachov DY, Kliemt K, Laubschat C, Echenique PM, Chulkov EV, Krellner C, Parkin SSP, Vyalikh DV, Ernst A, Kummer K. Long-lived spin waves in a metallic antiferromagnet. Nat Commun 2023; 14:5422. [PMID: 37669952 PMCID: PMC10480465 DOI: 10.1038/s41467-023-40963-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Accepted: 08/17/2023] [Indexed: 09/07/2023] Open
Abstract
Collective spin excitations in magnetically ordered crystals, called magnons or spin waves, can serve as carriers in novel spintronic devices with ultralow energy consumption. The generation of well-detectable spin flows requires long lifetimes of high-frequency magnons. In general, the lifetime of spin waves in a metal is substantially reduced due to a strong coupling of magnons to the Stoner continuum. This makes metals unattractive for use as components for magnonic devices. Here, we present the metallic antiferromagnet CeCo2P2, which exhibits long-living magnons even in the terahertz (THz) regime. For CeCo2P2, our first-principle calculations predict a suppression of low-energy spin-flip Stoner excitations, which is verified by resonant inelastic X-ray scattering measurements. By comparison to the isostructural compound LaCo2P2, we show how small structural changes can dramatically alter the electronic structure around the Fermi level leading to the classical picture of the strongly damped magnons intrinsic to metallic systems. Our results not only demonstrate that long-lived magnons in the THz regime can exist in bulk metallic systems, but they also open a path for an efficient search for metallic magnetic systems in which undamped THz magnons can be excited.
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Affiliation(s)
- G Poelchen
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38043, Grenoble, France.
- Institut für Festkörper- und Materialphysik, Technische Universität Dresden, 01062, Dresden, Germany.
- Max Planck Institute for Chemical Physics of Solids, Nöthnitzer Straße 40, 01187, Dresden, Germany.
| | - J Hellwig
- Kristall- und Materiallabor, Physikalisches Institut, Goethe-Universität Frankfurt, Max-von-Laue Strasse 1, 60438, Frankfurt am Main, Germany
| | - M Peters
- Kristall- und Materiallabor, Physikalisches Institut, Goethe-Universität Frankfurt, Max-von-Laue Strasse 1, 60438, Frankfurt am Main, Germany
| | - D Yu Usachov
- Donostia International Physics Center (DIPC), 20018, Donostia-San Sebastián, Spain
| | - K Kliemt
- Kristall- und Materiallabor, Physikalisches Institut, Goethe-Universität Frankfurt, Max-von-Laue Strasse 1, 60438, Frankfurt am Main, Germany
| | - C Laubschat
- Institut für Festkörper- und Materialphysik, Technische Universität Dresden, 01062, Dresden, Germany
| | - P M Echenique
- Donostia International Physics Center (DIPC), 20018, Donostia-San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, 48011, Bilbao, Spain
| | - E V Chulkov
- Donostia International Physics Center (DIPC), 20018, Donostia-San Sebastián, Spain
- Centro de Física de Materiales (CFM-MPC), Centro Mixto CSIC-UPV/EHU, 20018, Donostia-San Sebastián, Spain
- Departamento de Polímeros y Materiales Avanzados: Física, Química y Tecnología, Facultad de Ciencias Químicas, Universidad del País Vasco UPV/EHU, 20080, Donostia-San Sebastián, Spain
| | - C Krellner
- Kristall- und Materiallabor, Physikalisches Institut, Goethe-Universität Frankfurt, Max-von-Laue Strasse 1, 60438, Frankfurt am Main, Germany
| | - S S P Parkin
- Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, 06120, Halle, Germany
| | - D V Vyalikh
- Donostia International Physics Center (DIPC), 20018, Donostia-San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, 48011, Bilbao, Spain
| | - A Ernst
- Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, 06120, Halle, Germany
- Institut für Theoretische Physik, Johannes Kepler Universität, 4040, Linz, Austria
| | - K Kummer
- European Synchrotron Radiation Facility, 71 Avenue des Martyrs, 38043, Grenoble, France.
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4
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Zarzycki A, Perzanowski M, Krupinski M, Marszalek M. Solid-State Dewetting as a Driving Force for Structural Transformation and Magnetization Reversal Mechanism in FePd Thin Films. MATERIALS (BASEL, SWITZERLAND) 2022; 16:92. [PMID: 36614431 PMCID: PMC9821688 DOI: 10.3390/ma16010092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 12/15/2022] [Accepted: 12/17/2022] [Indexed: 06/17/2023]
Abstract
In this work, the process of solid-state dewetting in FePd thin films and its influence on structural transformation and magnetic properties is presented. The morphology, structure and magnetic properties of the FePd system subjected to annealing at 600 °C for different times were studied. The analysis showed a strong correlation between the dewetting process and various physical phenomena. In particular, the transition between the A1 phase and L10 phase is strongly influenced by and inextricably connected with solid-state dewetting. Major changes were observed when the film lost its continuity, including a fast growth of the L10 phase, changes in the magnetization reversal behavior or the induction of magnetic spring-like behavior.
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Paischer S, Buczek PA, Buczek N, Eilmsteiner D, Ernst A. Eigenmodes of a disordered FeCo magnonic crystal at finite temperatures. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:335804. [PMID: 34102617 DOI: 10.1088/1361-648x/ac0939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 06/08/2021] [Indexed: 06/12/2023]
Abstract
In this report we present a systematic study of the magnonic modes in the disordered Fe0.5Co0.5alloy based on the Heisenberg Hamiltonian using two complementary approaches. In order to account for substitutional disorder, on the one hand we directly average the transverse magnetic susceptibility in real space over different disorder configurations and on the other hand we use the coherent potential approximation (CPA). While the method of direct averaging is numerically exact, it is computationally expensive and limited by the maximal size of the supercell which can be simulated on a computer. On the contrary the CPA does not suffer from this drawback and yields a cheap numerical scheme. Therefore, we additionally compare the results of these two approaches and show that the CPA gives very good results for most of the magnetic properties considered in this report, including the magnon energies and the spatial shape of the eigenmodes. However, it turns out that while reproducing the general trend, the CPA systematically underestimates the disorder induced damping of the magnons. This provides evidence that the physics of impurity scattering in this system is governed by non-local effects missing in the CPA. Finally, we study the real space eigenmodes of the system, including their spatial shapes, and analyze their temperature dependence within the random phase approximation.
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Affiliation(s)
- S Paischer
- Institute for Theoretical Physics, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz, Austria
| | - P A Buczek
- Department of Engineering and Computer Sciences, Hamburg University of Applied Sciences, Berliner Tor 7, 20099 Hamburg, Germany
| | - N Buczek
- Department of Applied Natural Sciences, Lübeck University of Applied Sciences, Mönkhofer Weg 239, 23562 Lübeck, Germany
| | - D Eilmsteiner
- Institute for Theoretical Physics, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz, Austria
- Department of Engineering and Computer Sciences, Hamburg University of Applied Sciences, Berliner Tor 7, 20099 Hamburg, Germany
| | - A Ernst
- Institute for Theoretical Physics, Johannes Kepler University Linz, Altenberger Straße 69, 4040 Linz, Austria
- Max-Planck-Institut of Microstructure Physics, Weinberg 2, 06120 Halle (Saale), Germany
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6
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Zakeri K, Hjelt A, Maznichenko IV, Buczek P, Ernst A. Nonlinear Decay of Quantum Confined Magnons in Itinerant Ferromagnets. PHYSICAL REVIEW LETTERS 2021; 126:177203. [PMID: 33988456 DOI: 10.1103/physrevlett.126.177203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 04/06/2021] [Indexed: 06/12/2023]
Abstract
Quantum confinement leads to the emergence of several magnon modes in ultrathin layered magnetic structures. We probe the lifetime of these quantum confined modes in a model system composed of three atomic layers of Co grown on different surfaces. We demonstrate that the quantum confined magnons exhibit nonlinear decay rates, which strongly depend on the mode number, in sharp contrast to what is assumed in the classical dynamics. Combining the experimental results with those of linear-response density-functional calculations we provide a quantitative explanation for this nonlinear damping effect. The results provide new insights into the decay mechanism of spin excitations in ultrathin films and multilayers and pave the way for tuning the dynamical properties of such structures.
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Affiliation(s)
- Kh Zakeri
- Heisenberg Spin-Dynamics Group, Physikalisches Institut, Karlsruhe Institute of Technology, Wolfgang-Gaede-Strasse 1, D-76131 Karlsruhe, Germany
| | - A Hjelt
- Heisenberg Spin-Dynamics Group, Physikalisches Institut, Karlsruhe Institute of Technology, Wolfgang-Gaede-Strasse 1, D-76131 Karlsruhe, Germany
| | - I V Maznichenko
- Department of Engineering and Computer Sciences, Hamburg University of Applied Sciences, Berliner Tor 7, D-20099 Hamburg, Germany
| | - P Buczek
- Department of Engineering and Computer Sciences, Hamburg University of Applied Sciences, Berliner Tor 7, D-20099 Hamburg, Germany
| | - A Ernst
- Institute for Theoretical Physics, Johannes Kepler University, Altenberger Strasse 69, A-4040 Linz, Austria
- Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany
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7
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Park P, Park K, Kim T, Kousaka Y, Lee KH, Perring TG, Jeong J, Stuhr U, Akimitsu J, Kenzelmann M, Park JG. Momentum-Dependent Magnon Lifetime in the Metallic Noncollinear Triangular Antiferromagnet CrB_{2}. PHYSICAL REVIEW LETTERS 2020; 125:027202. [PMID: 32701352 DOI: 10.1103/physrevlett.125.027202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 06/19/2020] [Indexed: 06/11/2023]
Abstract
Noncollinear magnetic order arises for various reasons in several magnetic systems and exhibits interesting spin dynamics. Despite its ubiquitous presence, little is known of how magnons, otherwise stable quasiparticles, decay in these systems, particularly in metallic magnets. Using inelastic neutron scattering, we examine the magnetic excitation spectra in a metallic noncollinear antiferromagnet CrB_{2}, in which Cr atoms form a triangular lattice and display incommensurate magnetic order. Our data show intrinsic magnon damping and continuumlike excitations that cannot be explained by linear spin wave theory. The intrinsic magnon linewidth Γ(q,E_{q}) shows very unusual momentum dependence, which our analysis shows to originate from the combination of two-magnon decay and the Stoner continuum. By comparing the theoretical predictions with the experiments, we identify where in the momentum and energy space one of the two factors becomes more dominant. Our work constitutes a rare comprehensive study of the spin dynamics in metallic noncollinear antiferromagnets. It reveals, for the first time, definite experimental evidence of the higher-order effects in metallic antiferromagnets.
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Affiliation(s)
- Pyeongjae Park
- Center for Quantum Materials, Seoul National University, Seoul 08826, Republic of Korea
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
| | - Kisoo Park
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
| | - Taehun Kim
- Center for Quantum Materials, Seoul National University, Seoul 08826, Republic of Korea
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
| | - Yusuke Kousaka
- Department of Physics and Electronics, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan
| | - Ki Hoon Lee
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
- Center for Theoretical Physics of Complex Systems, Institute for Basic Science (IBS), Daejeon 34126, Korea
| | - T G Perring
- ISIS Pulsed Neutron and Muon Source, STFC Rutherford Appleton Laboratory, Didcot, Oxfordshire, OX11 0QX, United Kingdom
| | - Jaehong Jeong
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
| | - Uwe Stuhr
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - Jun Akimitsu
- Research Institute for Interdisciplinary Science, Okayama University, Okayama, Okayama 700-8530, Japan
| | - Michel Kenzelmann
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
| | - Je-Geun Park
- Center for Quantum Materials, Seoul National University, Seoul 08826, Republic of Korea
- Center for Correlated Electron Systems, Institute for Basic Science, Seoul 08826, Republic of Korea
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Republic of Korea
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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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Qin HJ, Tsurkan S, Ernst A, Zakeri K. Experimental Realization of Atomic-Scale Magnonic Crystals. PHYSICAL REVIEW LETTERS 2019; 123:257202. [PMID: 31922781 DOI: 10.1103/physrevlett.123.257202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Indexed: 06/10/2023]
Abstract
We introduce a new approach of materials design for terahertz magnonics making use of quantum confinement of terahertz magnons in layered ferromagnets. We show that in atomically designed multilayers composed of alternating atomic layers of ferromagnetic metals one can efficiently excite different magnon modes associated with the quantum confinement in the third dimension, i.e., the direction perpendicular to the layers. We demonstrate experimentally that the magnonic band structure of these systems can be tuned by changing the material combination and the number of atomic layers. We realize the idea of opening band gaps, with a size of up to several tens of millielectronvolts, between different terahertz magnon bands and thereby report on the first step toward the realization of atomic-scale magnonic crystals.
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Affiliation(s)
- H J Qin
- Heisenberg Spin-dynamics Group, Physikalisches Institut, Karlsruhe Institute of Technology, Wolfgang-Gaede-Straße 1, D-76131 Karlsruhe, Germany
- NanoSpin, Department of Applied Physics, Aalto University School of Science, FI-00076 Aalto, Finland
| | - S Tsurkan
- Heisenberg Spin-dynamics Group, Physikalisches Institut, Karlsruhe Institute of Technology, Wolfgang-Gaede-Straße 1, D-76131 Karlsruhe, Germany
| | - A Ernst
- Institute for Theoretical Physics, Johannes Kepler University, Altenberger Straße 69, 4040 Linz, Austria
- Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany
| | - Kh Zakeri
- Heisenberg Spin-dynamics Group, Physikalisches Institut, Karlsruhe Institute of Technology, Wolfgang-Gaede-Straße 1, D-76131 Karlsruhe, Germany
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Buczek P, Thomas S, Marmodoro A, Buczek N, Zubizarreta X, Hoffmann M, Balashov T, Wulfhekel W, Zakeri K, Ernst A. Spin waves in disordered materials. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2018; 30:423001. [PMID: 30182926 DOI: 10.1088/1361-648x/aadefb] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We present an efficient methodology to study spin waves in disordered materials. The approach is based on a Heisenberg model and enables calculations of magnon properties in spin systems with disorder of an arbitrary kind and concentration of impurities. Disorder effects are taken into account within two complementary approaches. Magnons in systems with substitutional (uncorrelated) disorder can be efficiently calculated within a single-site coherent potential approximation for the Heisenberg model. From the computation point of view the method is inexpensive and directly applicable to systems like alloys and doped materials. It is shown that it performs exceedingly well across all concentrations and wave vectors. Another way is the direct numerical simulation of large supercells using a configurational average over possible samples. This approach is applicable to systems with an arbitrary kind of disorder. The effective interaction between magnetic moments entering the Heisenberg model can be obtained from first-principles using a self-consistent Green function method within the density functional theory. Thus, our method can be viewed as an ab initio approach and can be used for calculations of magnons in real materials.
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Affiliation(s)
- Paweł Buczek
- Hochschule für Angewandte Wissenschaften Hamburg, Fakultät Technik und Informatik, Berliner Tor 7, 20099 Hamburg, Germany
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Qin HJ, Zakeri K, Ernst A, Kirschner J. Temperature Dependence of Magnetic Excitations: Terahertz Magnons above the Curie Temperature. PHYSICAL REVIEW LETTERS 2017; 118:127203. [PMID: 28388202 DOI: 10.1103/physrevlett.118.127203] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Indexed: 06/07/2023]
Abstract
When an ordered spin system of a given dimensionality undergoes a second order phase transition, the dependence of the order parameter, i.e., magnetization on temperature, can be well described by thermal excitations of elementary collective spin excitations (magnons). However, the behavior of magnons themselves, as a function of temperature and across the transition temperature T_{C}, is an unknown issue. Utilizing spin-polarized high resolution electron energy loss spectroscopy, we monitor the high-energy (terahertz) magnons, excited in an ultrathin ferromagnet, as a function of temperature. We show that the magnons' energy and lifetime decrease with temperature. The temperature-induced renormalization of the magnons' energy and lifetime depends on the wave vector. We provide quantitative results on the temperature-induced damping and discuss the possible mechanism, e.g., multimagnon scattering. A careful investigation of physical quantities determining the magnons' propagation indicates that terahertz magnons sustain their propagating character even at temperatures far above T_{C}.
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Affiliation(s)
- H J Qin
- Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany
| | - Kh Zakeri
- Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany
- Heisenberg Spin-dynamics Group, Physikalisches Institut, Karlsruhe Institute of Technology, Wolfgang-Gaede-Strasse 1, D-76131 Karlsruhe, Germany
| | - A Ernst
- Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany
| | - J Kirschner
- Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany
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Zakeri K. Probing of the interfacial Heisenberg and Dzyaloshinskii-Moriya exchange interaction by magnon spectroscopy. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2017; 29:013001. [PMID: 27831928 DOI: 10.1088/0953-8984/29/1/013001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
This Topical Review presents an overview of the recent experimental results on the quantitative determination of the magnetic exchange parameters in ultrathin magnetic films and multilayers grown on different substrates. The experimental approaches for probing both the symmetric Heisenberg and the antisymmetric Dzyaloshinskii-Moriya exchange interaction in ultrathin magnetic films and at interfaces are discussed in detail. It is explained how the experimental spectrum of magnetic excitations can be used to quantify the strength of these interactions.
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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. Max-Planck-Institut für Mikrostrukturphysik, Weinberg 2, D-06120 Halle, Germany
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