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Wang Q, Li M, Guo P, Gao L, Weng L, Huang W. Shape-position perceptive fusion electronic skin with autonomous learning for gesture interaction. MICROSYSTEMS & NANOENGINEERING 2024; 10:103. [PMID: 39045231 PMCID: PMC11263581 DOI: 10.1038/s41378-024-00739-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 05/13/2024] [Accepted: 06/19/2024] [Indexed: 07/25/2024]
Abstract
Wearable devices, such as data gloves and electronic skins, can perceive human instructions, behaviors and even emotions by tracking a hand's motion, with the help of knowledge learning. The shape or position single-mode sensor in such devices often lacks comprehensive information to perceive interactive gestures. Meanwhile, the limited computing power of wearable applications restricts the multimode fusion of different sensing data and the deployment of deep learning networks. We propose a perceptive fusion electronic skin (PFES) with a bioinspired hierarchical structure that utilizes the magnetization state of a magnetostrictive alloy film to be sensitive to external strain or magnetic field. Installed at the joints of a hand, the PFES realizes perception of curvature (joint shape) and magnetism (joint position) information by mapping corresponding signals to the two-directional continuous distribution such that the two edges represent the contributions of curvature radius and magnetic field, respectively. By autonomously selecting knowledge closer to the user's hand movement characteristics, the reinforced knowledge distillation method is developed to learn and compress a teacher model for rapid deployment on wearable devices. The PFES integrating the autonomous learning algorithm can fuse curvature-magnetism dual information, ultimately achieving human machine interaction with gesture recognition and haptic feedback for cross-space perception and manipulation.
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Affiliation(s)
- Qian Wang
- State Key Laboratory of Reliability and Intelligence of Electrical Equipment, Tianjin, China
- Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability of Hebei Province, School of Electrical Engineering, Hebei University of Technology, Tianjin, 300130 China
| | - Mingming Li
- State Key Laboratory of Reliability and Intelligence of Electrical Equipment, Tianjin, China
- Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability of Hebei Province, School of Electrical Engineering, Hebei University of Technology, Tianjin, 300130 China
| | - Pingping Guo
- State Key Laboratory of Reliability and Intelligence of Electrical Equipment, Tianjin, China
- Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability of Hebei Province, School of Electrical Engineering, Hebei University of Technology, Tianjin, 300130 China
| | - Liang Gao
- State Key Laboratory of Reliability and Intelligence of Electrical Equipment, Tianjin, China
- Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability of Hebei Province, School of Electrical Engineering, Hebei University of Technology, Tianjin, 300130 China
| | - Ling Weng
- State Key Laboratory of Reliability and Intelligence of Electrical Equipment, Tianjin, China
- Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability of Hebei Province, School of Electrical Engineering, Hebei University of Technology, Tianjin, 300130 China
| | - Wenmei Huang
- State Key Laboratory of Reliability and Intelligence of Electrical Equipment, Tianjin, China
- Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability of Hebei Province, School of Electrical Engineering, Hebei University of Technology, Tianjin, 300130 China
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2
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Reinhard M, Kunnus K, Ledbetter K, Biasin E, Zederkof DB, Alonso-Mori R, van Driel TB, Nelson S, Kozina M, Borkiewicz OJ, Lorenc M, Cammarata M, Collet E, Sokaras D, Cordones AA, Gaffney KJ. Observation of a Picosecond Light-Induced Spin Transition in Polymeric Nanorods. ACS NANO 2024; 18:15468-15476. [PMID: 38833689 DOI: 10.1021/acsnano.3c10042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2024]
Abstract
Spin transition (ST) materials are attractive for developing photoswitchable devices, but their slow material transformations limit device applications. Size reduction could enable faster switching, but the photoinduced dynamics at the nanoscale remains poorly understood. Here, we report a femtosecond optical pump multimodal X-ray probe study of polymeric nanorods. Simultaneously tracking the ST order parameter with X-ray emission spectroscopy and structure with X-ray diffraction, we observe photodoping of the low-spin-lattice within ∼150 fs. Above a ∼16% photodoping threshold, the transition to the high-spin phase occurs following an incubation period assigned to vibrational energy redistribution within the nanorods activating the molecular spin switching. Above ∼60% photodoping, the incubation period disappears, and the transition completes within ∼50 ps, preceded by the elastic nanorod expansion in response to the photodoping. These results support the feasibility of ST material-based GHz optical switching applications.
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Affiliation(s)
- Marco Reinhard
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Kristjan Kunnus
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Kathryn Ledbetter
- Department of Physics, Stanford University, Stanford, California 94305, United States
| | - Elisa Biasin
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | | | - Roberto Alonso-Mori
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Tim Brandt van Driel
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Silke Nelson
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Michael Kozina
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Olaf J Borkiewicz
- X-ray Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Maciej Lorenc
- Univ Rennes, CNRS, IPR (Institut de Physique de Rennes)─UMR 6251, 35000 Rennes, France
| | - Marco Cammarata
- Univ Rennes, CNRS, IPR (Institut de Physique de Rennes)─UMR 6251, 35000 Rennes, France
| | - Eric Collet
- Univ Rennes, CNRS, IPR (Institut de Physique de Rennes)─UMR 6251, 35000 Rennes, France
| | - Dimosthenis Sokaras
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Amy A Cordones
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Kelly J Gaffney
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
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3
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Lee Y, Oang KY, Kim D, Ihee H. A comparative review of time-resolved x-ray and electron scattering to probe structural dynamics. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2024; 11:031301. [PMID: 38706888 PMCID: PMC11065455 DOI: 10.1063/4.0000249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Accepted: 04/10/2024] [Indexed: 05/07/2024]
Abstract
The structure of molecules, particularly the dynamic changes in structure, plays an essential role in understanding physical and chemical phenomena. Time-resolved (TR) scattering techniques serve as crucial experimental tools for studying structural dynamics, offering direct sensitivity to molecular structures through scattering signals. Over the past decade, the advent of x-ray free-electron lasers (XFELs) and mega-electron-volt ultrafast electron diffraction (MeV-UED) facilities has ushered TR scattering experiments into a new era, garnering significant attention. In this review, we delve into the basic principles of TR scattering experiments, especially focusing on those that employ x-rays and electrons. We highlight the variations in experimental conditions when employing x-rays vs electrons and discuss their complementarity. Additionally, cutting-edge XFELs and MeV-UED facilities for TR x-ray and electron scattering experiments and the experiments performed at those facilities are reviewed. As new facilities are constructed and existing ones undergo upgrades, the landscape for TR x-ray and electron scattering experiments is poised for further expansion. Through this review, we aim to facilitate the effective utilization of these emerging opportunities, assisting researchers in delving deeper into the intricate dynamics of molecular structures.
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Affiliation(s)
| | - Key Young Oang
- Radiation Center for Ultrafast Science, Korea Atomic Energy Research Institute (KAERI), Daejeon 34057, South Korea
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4
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Shokeen V, Heber M, Kutnyakhov D, Wang X, Yaroslavtsev A, Maldonado P, Berritta M, Wind N, Wenthaus L, Pressacco F, Min CH, Nissen M, Mahatha SK, Dziarzhytski S, Oppeneer PM, Rossnagel K, Elmers HJ, Schönhense G, Dürr HA. Real-time observation of non-equilibrium phonon-electron energy and angular momentum flow in laser-heated nickel. SCIENCE ADVANCES 2024; 10:eadj2407. [PMID: 38295169 PMCID: PMC10830112 DOI: 10.1126/sciadv.adj2407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Accepted: 12/29/2023] [Indexed: 02/02/2024]
Abstract
Identifying the microscopic nature of non-equilibrium energy transfer mechanisms among electronic, spin, and lattice degrees of freedom is central to understanding ultrafast phenomena such as manipulating magnetism on the femtosecond timescale. Here, we use time- and angle-resolved photoemission spectroscopy to go beyond the often-used ensemble-averaged view of non-equilibrium dynamics in terms of quasiparticle temperature evolutions. We show for ferromagnetic Ni that the non-equilibrium electron and spin dynamics display pronounced variations with electron momentum, whereas the magnetic exchange interaction remains isotropic. This highlights the influence of lattice-mediated scattering processes and opens a pathway toward unraveling the still elusive microscopic mechanism of spin-lattice angular momentum transfer.
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Affiliation(s)
- Vishal Shokeen
- Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden
| | - Michael Heber
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
| | | | - Xiaocui Wang
- Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden
| | | | - Pablo Maldonado
- Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden
| | - Marco Berritta
- Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden
| | - Nils Wind
- Institut für Experimentalphysik, Universität Hamburg, 22761 Hamburg, Germany
- Ruprecht Haensel Laboratory, Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
| | - Lukas Wenthaus
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
| | | | - Chul-Hee Min
- Ruprecht Haensel Laboratory, Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
| | - Matz Nissen
- Institut für Experimentalphysik, Universität Hamburg, 22761 Hamburg, Germany
| | - Sanjoy K. Mahatha
- Ruprecht Haensel Laboratory, Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
| | | | - Peter M. Oppeneer
- Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden
| | - Kai Rossnagel
- Ruprecht Haensel Laboratory, Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
- Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, 24098 Kiel, Germany
| | - Hans-Joachim Elmers
- Institut für Physik, Johannes Gutenberg-Universität Mainz, 55128 Mainz, Germany
| | - Gerd Schönhense
- Institut für Physik, Johannes Gutenberg-Universität Mainz, 55128 Mainz, Germany
| | - Hermann A. Dürr
- Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden
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5
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Sun J, Shi S, Wang J. Acoustic Waves Induced by Einstein-de Haas Effect in the Ultrafast Core Reversal of Magnetic Vortex. PHYSICAL REVIEW LETTERS 2023; 130:256701. [PMID: 37418721 DOI: 10.1103/physrevlett.130.256701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 05/19/2023] [Indexed: 07/09/2023]
Abstract
The interaction between acoustic wave and magnetization in ferromagnetic thin films has attracted great attention due to its interesting physics and potential applications. However, up to now, the magneto-acoustic interaction has mainly been studied on the basis of magnetostriction. In this Letter, we develop a phase field model of magneto-acoustic interaction based on the Einstein-de Haas effect, and predict the acoustic wave during the ultrafast core reversal of magnetic vortex in a ferromagnetic disk. Because of the Einstein-de Haas effect, the ultrafast change of magnetization at the vortex core leads to a large mechanical angular momentum, which induces a body couple at the vortex core and excites a high-frequency acoustic wave. Moreover, the displacement amplitude of the acoustic wave is highly dependent on the gyromagnetic ratio. The smaller the gyromagnetic ratio is, the larger the displacement amplitude is. The present work not only provides a new mechanism for dynamic magnetoelastic coupling but also sheds new insights on the magneto-acoustic interaction.
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Affiliation(s)
- Jiajun Sun
- Department of Engineering Mechanics, Zhejiang University, Zheda Road 38, Hangzhou, Zhejiang 310027, China
| | - Shengbin Shi
- Department of Engineering Mechanics, Zhejiang University, Zheda Road 38, Hangzhou, Zhejiang 310027, China
| | - Jie Wang
- Department of Engineering Mechanics, Zhejiang University, Zheda Road 38, Hangzhou, Zhejiang 310027, China
- Zhejiang Laboratory, Hangzhou, Zhejiang 311100, China
- Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province, Zheda Road 38, Hangzhou, Zhejiang 310027, China
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6
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Mattern M, von Reppert A, Zeuschner SP, Herzog M, Pudell JE, Bargheer M. Concepts and use cases for picosecond ultrasonics with x-rays. PHOTOACOUSTICS 2023; 31:100503. [PMID: 37275326 PMCID: PMC10238750 DOI: 10.1016/j.pacs.2023.100503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 04/28/2023] [Accepted: 04/30/2023] [Indexed: 06/07/2023]
Abstract
This review discusses picosecond ultrasonics experiments using ultrashort hard x-ray probe pulses to extract the transient strain response of laser-excited nanoscopic structures from Bragg-peak shifts. This method provides direct, layer-specific, and quantitative information on the picosecond strain response for structures down to few-nm thickness. We model the transient strain using the elastic wave equation and express the driving stress using Grüneisen parameters stating that the laser-induced stress is proportional to energy density changes in the microscopic subsystems of the solid, i.e., electrons, phonons and spins. The laser-driven strain response can thus serve as an ultrafast proxy for local energy-density and temperature changes, but we emphasize the importance of the nanoscale morphology for an accurate interpretation due to the Poisson effect. The presented experimental use cases encompass ultrathin and opaque metal-heterostructures, continuous and granular nanolayers as well as negative thermal expansion materials, that each pose a challenge to established all-optical techniques.
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Affiliation(s)
- Maximilian Mattern
- Institut für Physik & Astronomie, Universität Potsdam, 14476 Potsdam, Germany
| | | | - Steffen Peer Zeuschner
- Institut für Physik & Astronomie, Universität Potsdam, 14476 Potsdam, Germany
- Helmholtz Zentrum Berlin, 12489 Berlin, Germany
| | - Marc Herzog
- Institut für Physik & Astronomie, Universität Potsdam, 14476 Potsdam, Germany
| | - Jan-Etienne Pudell
- Institut für Physik & Astronomie, Universität Potsdam, 14476 Potsdam, Germany
- Helmholtz Zentrum Berlin, 12489 Berlin, Germany
- European XFEL, 22869 Schenefeld, Germany
| | - Matias Bargheer
- Institut für Physik & Astronomie, Universität Potsdam, 14476 Potsdam, Germany
- Helmholtz Zentrum Berlin, 12489 Berlin, Germany
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7
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Mattern M, Pudell JE, Dumesnil K, von Reppert A, Bargheer M. Towards shaping picosecond strain pulses via magnetostrictive transducers. PHOTOACOUSTICS 2023; 30:100463. [PMID: 36874592 PMCID: PMC9982602 DOI: 10.1016/j.pacs.2023.100463] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 02/12/2023] [Accepted: 02/14/2023] [Indexed: 06/07/2023]
Abstract
Using time-resolved x-ray diffraction, we demonstrate the manipulation of the picosecond strain response of a metallic heterostructure consisting of a dysprosium (Dy) transducer and a niobium (Nb) detection layer by an external magnetic field. We utilize the first-order ferromagnetic-antiferromagnetic phase transition of the Dy layer, which provides an additional large contractive stress upon laser excitation compared to its zero-field response. This enhances the laser-induced contraction of the transducer and changes the shape of the picosecond strain pulses driven in Dy and detected within the buried Nb layer. Based on our experiment with rare-earth metals we discuss required properties for functional transducers, which may allow for novel field-control of the emitted picosecond strain pulses.
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Affiliation(s)
- Maximilian Mattern
- Institut für Physik & Astronomie, Universität Potsdam, 14476 Potsdam, Germany
| | - Jan-Etienne Pudell
- Institut für Physik & Astronomie, Universität Potsdam, 14476 Potsdam, Germany
- European XFEL, 22869 Schenefeld, Germany
| | - Karine Dumesnil
- Institut Jean Lamour (UMR CNRS 7198), Université Lorraine, 54000 Nancy, France
| | | | - Matias Bargheer
- Institut für Physik & Astronomie, Universität Potsdam, 14476 Potsdam, Germany
- Helmholtz Zentrum Berlin, 12489 Berlin, Germany
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8
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Luo D, Zhang B, Sie EJ, Nyby CM, Fan Q, Shen X, Reid AH, Hoffmann MC, Weathersby S, Wen J, Qian X, Wang X, Lindenberg AM. Ultrafast Optomechanical Strain in Layered GeS. NANO LETTERS 2023; 23:2287-2294. [PMID: 36898060 DOI: 10.1021/acs.nanolett.2c05048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Strong coupling between light and mechanical strain forms the foundation for next-generation optical micro- and nano-electromechanical systems. Such optomechanical responses in two-dimensional materials present novel types of functionalities arising from the weak van der Waals bond between atomic layers. Here, by using structure-sensitive megaelectronvolt ultrafast electron diffraction, we report the experimental observation of optically driven ultrafast in-plane strain in the layered group IV monochalcogenide germanium sulfide (GeS). Surprisingly, the photoinduced structural deformation exhibits strain amplitudes of order 0.1% with a 10 ps fast response time and a significant in-plane anisotropy between zigzag and armchair crystallographic directions. Rather than arising due to heating, experimental and theoretical investigations suggest deformation potentials caused by electronic density redistribution and converse piezoelectric effects generated by photoinduced electric fields are the dominant contributors to the observed dynamic anisotropic strains. Our observations define new avenues for ultrafast optomechanical control and strain engineering within functional devices.
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Affiliation(s)
- Duan Luo
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
- Key Laboratory of Ultra-fast Photoelectric Diagnostics Technology, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi'an 710119, China
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Baiyu Zhang
- Department of Materials Science and Engineering, Texas A&M University, College Station, Texas 77843, United States
| | - Edbert J Sie
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
- Geballe Laboratory for Advanced Materials, Stanford University, Stanford, California 94305, United States
| | - Clara M Nyby
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Qingyuan Fan
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Xiaozhe Shen
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Alexander H Reid
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Matthias C Hoffmann
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Stephen Weathersby
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Jianguo Wen
- Center for Nanoscale Materials, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Xiaofeng Qian
- Department of Materials Science and Engineering, Texas A&M University, College Station, Texas 77843, United States
| | - Xijie Wang
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Aaron M Lindenberg
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
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9
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Zhou Hagström N, Schneider M, Kerber N, Yaroslavtsev A, Burgos Parra E, Beg M, Lang M, Günther CM, Seng B, Kammerbauer F, Popescu H, Pancaldi M, Neeraj K, Polley D, Jangid R, Hrkac SB, Patel SKK, Ovcharenko S, Turenne D, Ksenzov D, Boeglin C, Baidakova M, von Korff Schmising C, Borchert M, Vodungbo B, Chen K, Luo C, Radu F, Müller L, Martínez Flórez M, Philippi-Kobs A, Riepp M, Roseker W, Grübel G, Carley R, Schlappa J, Van Kuiken BE, Gort R, Mercadier L, Agarwal N, Le Guyader L, Mercurio G, Teichmann M, Delitz JT, Reich A, Broers C, Hickin D, Deiter C, Moore J, Rompotis D, Wang J, Kane D, Venkatesan S, Meier J, Pallas F, Jezynski T, Lederer M, Boukhelef D, Szuba J, Wrona K, Hauf S, Zhu J, Bergemann M, Kamil E, Kluyver T, Rosca R, Spirzewski M, Kuster M, Turcato M, Lomidze D, Samartsev A, Engelke J, Porro M, Maffessanti S, Hansen K, Erdinger F, Fischer P, Fiorini C, Castoldi A, Manghisoni M, Wunderer CB, Fullerton EE, Shpyrko OG, Gutt C, Sanchez-Hanke C, Dürr HA, Iacocca E, Nembach HT, Keller MW, Shaw JM, Silva TJ, Kukreja R, Fangohr H, Eisebitt S, Kläui M, Jaouen N, Scherz A, Bonetti S, Jal E. Megahertz-rate ultrafast X-ray scattering and holographic imaging at the European XFEL. JOURNAL OF SYNCHROTRON RADIATION 2022; 29:1454-1464. [PMID: 36345754 PMCID: PMC9641564 DOI: 10.1107/s1600577522008414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 08/23/2022] [Indexed: 06/16/2023]
Abstract
The advent of X-ray free-electron lasers (XFELs) has revolutionized fundamental science, from atomic to condensed matter physics, from chemistry to biology, giving researchers access to X-rays with unprecedented brightness, coherence and pulse duration. All XFEL facilities built until recently provided X-ray pulses at a relatively low repetition rate, with limited data statistics. Here, results from the first megahertz-repetition-rate X-ray scattering experiments at the Spectroscopy and Coherent Scattering (SCS) instrument of the European XFEL are presented. The experimental capabilities that the SCS instrument offers, resulting from the operation at megahertz repetition rates and the availability of the novel DSSC 2D imaging detector, are illustrated. Time-resolved magnetic X-ray scattering and holographic imaging experiments in solid state samples were chosen as representative, providing an ideal test-bed for operation at megahertz rates. Our results are relevant and applicable to any other non-destructive XFEL experiments in the soft X-ray range.
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Affiliation(s)
| | - Michael Schneider
- Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, 12489 Berlin, Germany
| | - Nico Kerber
- Institute of Physics, Johannes Gutenberg-University Mainz, 55099 Mainz, Germany
| | - Alexander Yaroslavtsev
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
- Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden
| | - Erick Burgos Parra
- Synchrotron SOLEIL, Saint-Aubin, Boite Postale 48, 91192 Gif-sur-Yvette Cedex, France
- Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767 Palaiseau, France
| | - Marijan Beg
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
- Department of Earth Science and Engineering, Imperial College London, London SW7 2AZ, United Kingdom
| | - Martin Lang
- Faculty of Engineering and Physical Sciences, University of Southampton, Southampton SO17 1BJ, United Kingdom
- Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Christian M. Günther
- Technische Universität Berlin, Zentraleinrichtung Elektronenmikroskopie (ZELMI), Berlin, Germany
| | - Boris Seng
- Institute of Physics, Johannes Gutenberg-University Mainz, 55099 Mainz, Germany
- Institut Jean Lamour, Nancy, France
| | - Fabian Kammerbauer
- Institute of Physics, Johannes Gutenberg-University Mainz, 55099 Mainz, Germany
| | - Horia Popescu
- Synchrotron SOLEIL, Saint-Aubin, Boite Postale 48, 91192 Gif-sur-Yvette Cedex, France
| | - Matteo Pancaldi
- Department of Physics, Stockholm University, 106 91 Stockholm, Sweden
| | - Kumar Neeraj
- Department of Physics, Stockholm University, 106 91 Stockholm, Sweden
| | - Debanjan Polley
- Department of Physics, Stockholm University, 106 91 Stockholm, Sweden
| | - Rahul Jangid
- Department of Materials Science and Engineering, University of California Davis, CA, USA
| | - Stjepan B. Hrkac
- Department of Physics, University of California San Diego, La Jolla, CA 92093, USA
| | - Sheena K. K. Patel
- Department of Physics, University of California San Diego, La Jolla, CA 92093, USA
- Center for Memory and Recording Research, University of California San Diego, La Jolla, CA 92093, USA
| | | | - Diego Turenne
- Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden
| | - Dmitriy Ksenzov
- Naturwissenschaftlich-Technische Fakultät – Department Physik, Universität Siegen, Siegen, Germany
| | - Christine Boeglin
- University of Strasbourg – CNRS, IPCMS, UMR 7504, 67000 Strasbourg, France
| | - Marina Baidakova
- Ioffe Institute, 26 Politekhnicheskaya, St Petersburg 194021, Russian Federation
| | | | - Martin Borchert
- Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, 12489 Berlin, Germany
| | - Boris Vodungbo
- Sorbonne Université, CNRS, Laboratoire de Chimie Physique – Matière et Rayonnement, LCPMR, 75005 Paris, France
| | - Kai Chen
- Helmholtz-Zentrum Berlin für Materialien und Energie, 12489 Berlin, Germany
| | - Chen Luo
- Helmholtz-Zentrum Berlin für Materialien und Energie, 12489 Berlin, Germany
| | - Florin Radu
- Helmholtz-Zentrum Berlin für Materialien und Energie, 12489 Berlin, Germany
| | - Leonard Müller
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
- Universität Hamburg, Hamburg, Germany
| | | | | | - Matthias Riepp
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
| | | | - Gerhard Grübel
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
| | - Robert Carley
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | | | | | - Rafael Gort
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | | | - Naman Agarwal
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
- Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000C Aarhus, Denmark
| | | | | | | | | | | | | | - David Hickin
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | | | - James Moore
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | | | - Jinxiong Wang
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Daniel Kane
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | | | - Joachim Meier
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | | | | | | | | | - Janusz Szuba
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | | | - Steffen Hauf
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Jun Zhu
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | | | - Ebad Kamil
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | | | - Robert Rosca
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Michał Spirzewski
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
- National Centre for Nuclear Research (NCBJ), A. Solłana 7, 05-400 Otwock-Świerk, Poland
| | - Markus Kuster
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | | | - David Lomidze
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Andrey Samartsev
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - Jan Engelke
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Matteo Porro
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
- Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, 30172 Venezia, Italy
| | | | - Karsten Hansen
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
| | - Florian Erdinger
- Institute of Computer Engineering, Heidelberg University, Germany
| | - Peter Fischer
- Institute of Computer Engineering, Heidelberg University, Germany
| | - Carlo Fiorini
- Politecnico di Milano, Dipartimento di Elettronica, Informazione e Bioingegneria, 20133 Milano, Italy
- Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Milano, Italy
| | - Andrea Castoldi
- Politecnico di Milano, Dipartimento di Elettronica, Informazione e Bioingegneria, 20133 Milano, Italy
- Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Milano, Italy
| | - Massimo Manghisoni
- Dipartimento di Ingegneria e Scienze Applicate, Università degli Studi di Bergamo, Dalmine, Italy
| | - Cornelia Beatrix Wunderer
- Deutsches Elektronen-Synchrotron DESY, 22607 Hamburg, Germany
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - Eric E. Fullerton
- Center for Memory and Recording Research, University of California San Diego, La Jolla, CA 92093, USA
| | - Oleg G. Shpyrko
- Department of Physics, University of California San Diego, La Jolla, CA 92093, USA
| | - Christian Gutt
- Naturwissenschaftlich-Technische Fakultät – Department Physik, Universität Siegen, Siegen, Germany
| | | | - Hermann A. Dürr
- Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden
| | - Ezio Iacocca
- Center for Magnetism and Magnetic Materials, University of Colorado Colorado Springs, Colorado Springs, CO 80918, USA
| | - Hans T. Nembach
- Department of Physics, University of Colorado, Boulder, CO 80309, USA
- Associate, Physical Measurement Laboratory, National Institute of Standards and Technology, Boulder, CO 80305, USA
| | - Mark W. Keller
- Quantum Electromagnetics Division, National Institute of Standards and Technology, Boulder, CO, USA
| | - Justin M. Shaw
- Quantum Electromagnetics Division, National Institute of Standards and Technology, Boulder, CO, USA
| | - Thomas J. Silva
- Quantum Electromagnetics Division, National Institute of Standards and Technology, Boulder, CO, USA
| | - Roopali Kukreja
- Department of Materials Science and Engineering, University of California Davis, CA, USA
| | - Hans Fangohr
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
- Faculty of Engineering and Physical Sciences, University of Southampton, Southampton SO17 1BJ, United Kingdom
- Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Stefan Eisebitt
- Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, 12489 Berlin, Germany
- Technische Universität Berlin, Institut für Optik und Atomare Physik, Berlin, Germany
| | - Mathias Kläui
- Institute of Physics, Johannes Gutenberg-University Mainz, 55099 Mainz, Germany
| | - Nicolas Jaouen
- Synchrotron SOLEIL, Saint-Aubin, Boite Postale 48, 91192 Gif-sur-Yvette Cedex, France
| | | | - Stefano Bonetti
- Department of Physics, Stockholm University, 106 91 Stockholm, Sweden
- Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, 30172 Venezia, Italy
| | - Emmanuelle Jal
- Sorbonne Université, CNRS, Laboratoire de Chimie Physique – Matière et Rayonnement, LCPMR, 75005 Paris, France
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10
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Turenne D, Yaroslavtsev A, Wang X, Unikandanuni V, Vaskivskyi I, Schneider M, Jal E, Carley R, Mercurio G, Gort R, Agarwal N, Van Kuiken B, Mercadier L, Schlappa J, Le Guyader L, Gerasimova N, Teichmann M, Lomidze D, Castoldi A, Potorochin D, Mukkattukavil D, Brock J, Zhou Hagström N, Reid AH, Shen X, Wang XJ, Maldonado P, Kvashnin Y, Carva K, Wang J, Takahashi YK, Fullerton EE, Eisebitt S, Oppeneer PM, Molodtsov S, Scherz A, Bonetti S, Iacocca E, Dürr HA. Nonequilibrium sub-10 nm spin-wave soliton formation in FePt nanoparticles. SCIENCE ADVANCES 2022; 8:eabn0523. [PMID: 35363518 PMCID: PMC10938569 DOI: 10.1126/sciadv.abn0523] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 02/10/2022] [Indexed: 06/14/2023]
Abstract
Magnetic nanoparticles such as FePt in the L10 phase are the bedrock of our current data storage technology. As the grains become smaller to keep up with technological demands, the superparamagnetic limit calls for materials with higher magnetocrystalline anisotropy. This, in turn, reduces the magnetic exchange length to just a few nanometers, enabling magnetic structures to be induced within the nanoparticles. Here, we describe the existence of spin-wave solitons, dynamic localized bound states of spin-wave excitations, in FePt nanoparticles. We show with time-resolved x-ray diffraction and micromagnetic modeling that spin-wave solitons of sub-10 nm sizes form out of the demagnetized state following femtosecond laser excitation. The measured soliton spin precession frequency of 0.1 THz positions this system as a platform to develop novel miniature devices.
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Affiliation(s)
- Diego Turenne
- Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden
| | - Alexander Yaroslavtsev
- Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden
- European XFEL GmbH, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Xiaocui Wang
- Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden
| | | | - Igor Vaskivskyi
- Complex Matter Department, Jožef Stefan Institute, Ljubljana, Slovenia
| | | | - Emmanuelle Jal
- Sorbonne Université, CNRS, Laboratoire de Chimie Physique-Matière et Rayonnement, 75005 Paris, France
| | - Robert Carley
- European XFEL GmbH, Holzkoppel 4, 22869 Schenefeld, Germany
| | | | - Rafael Gort
- European XFEL GmbH, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Naman Agarwal
- European XFEL GmbH, Holzkoppel 4, 22869 Schenefeld, Germany
| | | | | | | | | | | | | | - David Lomidze
- European XFEL GmbH, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Andrea Castoldi
- Dipartimento di Elettronica, Informazione e Bioingegneria, Politecnico di Milano, Milano, Italy
- Istituto Nazionale di Fisica Nucleare, Sezione di Milano, Milano, Italy
| | - Dimitri Potorochin
- European XFEL GmbH, Holzkoppel 4, 22869 Schenefeld, Germany
- Deutsches Elektronen-Synchrotron, 22607 Hamburg, Germany
- Institute of Experimental Physics, Technische Universität Bergakademie Freiberg, 09599 Freiberg, Germany
| | | | - Jeffrey Brock
- Center for Memory and Recording Research, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0401, USA
| | | | - Alexander H. Reid
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025, USA
| | - Xiaozhe Shen
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025, USA
| | - Xijie J. Wang
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025, USA
| | - Pablo Maldonado
- Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden
| | - Yaroslav Kvashnin
- Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden
| | - Karel Carva
- Faculty of Mathematics and Physics, Department of Condensed Matter Physics, Charles University, Ke Karlovu 5, 121 16 Prague, Czech Republic
| | - Jian Wang
- Magnet Materials Unit, National Institute for Materials Science, Tsukuba 305-0047, Japan
| | - Yukiko K. Takahashi
- Magnet Materials Unit, National Institute for Materials Science, Tsukuba 305-0047, Japan
| | - Eric E. Fullerton
- Center for Memory and Recording Research, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0401, USA
| | - Stefan Eisebitt
- Max-Born-Institut, Berlin, Germany
- Institut für Optik und Atomare Physik, Technische Universität Berlin, Berlin, Germany
| | - Peter M. Oppeneer
- Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden
| | - Serguei Molodtsov
- European XFEL GmbH, Holzkoppel 4, 22869 Schenefeld, Germany
- Institute of Experimental Physics, Technische Universität Bergakademie Freiberg, 09599 Freiberg, Germany
| | - Andreas Scherz
- European XFEL GmbH, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Stefano Bonetti
- Department of Physics, Stockholm University, 106 91 Stockholm, Sweden
- Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, 30172 Venice, Italy
| | - Ezio Iacocca
- Department of Mathematics, Physics and Electrical Engineering, Northumbria University, Newcastle upon Tyne NE1 8ST, UK
- Center for Magnetism and Magnetic Materials, University of Colorado Colorado Springs, Colorado Springs, CO 80918, USA
| | - Hermann A. Dürr
- Department of Physics and Astronomy, Uppsala University, 751 20 Uppsala, Sweden
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11
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Dürr HA, Ernstorfer R, Siwick BJ. Revealing momentum-dependent electron-phonon and phonon-phonon coupling in complex materials with ultrafast electron diffuse scattering. MRS BULLETIN 2021; 46:731-737. [PMID: 34720390 PMCID: PMC8550364 DOI: 10.1557/s43577-021-00156-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Accepted: 07/14/2021] [Indexed: 06/13/2023]
Abstract
ABSTRACT Despite their fundamental role in determining many important properties of materials, detailed momentum-dependent information on the strength of electron-phonon and phonon-phonon coupling across the entire Brillouin zone has remained elusive. Ultrafast electron diffuse scattering (UEDS) is a recently developed technique that is making a significant contribution to these questions. Here, we describe both the UEDS methodology and the information content of ultrafast, photoinduced changes in phonon-diffuse scattering from single-crystal materials. We present results obtained from Ni, WSe2, and TiSe2, materials that are characterized by a complex interplay between electronic (charge, spin) and lattice degrees of freedom. We demonstrate the power of this technique by unraveling carrier-phonon and phonon-phonon interactions in both momentum and time and following nonequilibrium phonon dynamics in detail on ultrafast time scales. By combining ab initio calculations with ultrafast diffuse electron scattering, insights into electronic and magnetic dynamics that impact UEDS indirectly can also be obtained.
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Affiliation(s)
- Hermann A. Dürr
- Department of Physics and Astronomy, Uppsala University, P.O. Box 516, 75120 Uppsala, Sweden
| | - Ralph Ernstorfer
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - Bradley J. Siwick
- Centre for the Physics of Materials, McGill University, 801 Sherbrooke St. W, Montreal, Canada
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12
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Shin Y, Kim JW. Magneto-optical Kerr effect measurement in ultrafast Sagnac interferometry using the Jones matrix approach. OPTICS LETTERS 2021; 46:3364-3367. [PMID: 34264214 DOI: 10.1364/ol.429988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 06/10/2021] [Indexed: 06/13/2023]
Abstract
We report the Jones matrix formalism of the magneto-optic Kerr effect (MOKE) for ferromagnets using an ultrafast Sagnac interferometer. Compared to the time-resolved MOKE instrument, the Sagnac interferometer has the advantage of obtaining the real and imaginary parts of the differential MOKE signal as well as the differential reflectivity and the lattice displacement at the same time. In addition, a simple method to obtain the static values of Kerr rotation and ellipticity is presented.
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13
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Time-Resolved XUV Absorption Spectroscopy and Magnetic Circular Dichroism at the Ni M2,3-Edges. APPLIED SCIENCES-BASEL 2020. [DOI: 10.3390/app11010325] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Ultrashort optical pulses can trigger a variety of non-equilibrium processes in magnetic thin films affecting electrons and spins on femtosecond timescales. In order to probe the charge and magnetic degrees of freedom simultaneously, we developed an X-ray streaking technique that has the advantage of providing a jitter-free picture of absorption cross-section changes. In this paper, we present an experiment based on this approach, which we performed using five photon probing energies at the Ni M2,3-edges. This allowed us to retrieve the absorption and magnetic circular dichroism time traces, yielding detailed information on transient modifications of electron and spin populations close to the Fermi level. Our findings suggest that the observed absorption and magnetic circular dichroism dynamics both depend on the extreme ultraviolet (XUV) probing wavelength, and can be described, at least qualitatively, by assuming ultrafast energy shifts of the electronic and magnetic elemental absorption resonances, as reported in recent work. However, our analysis also hints at more complex changes, highlighting the need for further experimental and theoretical studies in order to gain a thorough understanding of the interplay of electronic and spin degrees of freedom in optically excited magnetic thin films.
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14
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Nakamura A, Shimojima T, Chiashi Y, Kamitani M, Sakai H, Ishiwata S, Li H, Ishizaka K. Nanoscale Imaging of Unusual Photoacoustic Waves in Thin Flake VTe 2. NANO LETTERS 2020; 20:4932-4938. [PMID: 32463678 DOI: 10.1021/acs.nanolett.0c01006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The control of acoustic phonons, which are the carriers of sound and heat, has become the focus of increasing attention because of a demand for manipulating the sonic and thermal properties of nanometric devices. In particular, the photoacoustic effect using ultrafast optical pulses has a promising potential for the optical manipulation of phonons in the picosecond time regime. So far, its mechanism has been mostly based on the commonplace thermoelastic expansion in isotropic media, which has limited applicability. In this study, we investigate a conceptually new mechanism of the photoacoustic effect involving a structural instability that utilizes a transition-metal dichalcogenide VTe2 with a ribbon-type charge-density-wave (CDW). Ultrafast electron microscope imaging and diffraction measurements reveal the generation and propagation of unusual acoustic waves in a nanometric thin plate associated with optically induced instantaneous CDW dissolution. Our results highlight the capability of photoinduced structural instabilities as a source of coherent acoustic waves.
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Affiliation(s)
- Asuka Nakamura
- RIKEN Center for Emergent Matter Science, Wako, Saitama 351-0198, Japan
| | | | - Yusuke Chiashi
- Quantum-Phase Electronics Center and Department of Applied Physics, The University of Tokyo, Hongo, Tokyo 113-8656, Japan
| | - Manabu Kamitani
- RIKEN Center for Emergent Matter Science, Wako, Saitama 351-0198, Japan
| | - Hideaki Sakai
- Department of Physics, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Shintaro Ishiwata
- Quantum-Phase Electronics Center and Department of Applied Physics, The University of Tokyo, Hongo, Tokyo 113-8656, Japan
- Division of Materials Physics, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Han Li
- Quantum-Phase Electronics Center and Department of Applied Physics, The University of Tokyo, Hongo, Tokyo 113-8656, Japan
| | - Kyoko Ishizaka
- RIKEN Center for Emergent Matter Science, Wako, Saitama 351-0198, Japan
- Quantum-Phase Electronics Center and Department of Applied Physics, The University of Tokyo, Hongo, Tokyo 113-8656, Japan
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15
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von Reppert A, Willig L, Pudell JE, Zeuschner SP, Sellge G, Ganss F, Hellwig O, Arregi JA, Uhlíř V, Crut A, Bargheer M. Spin stress contribution to the lattice dynamics of FePt. SCIENCE ADVANCES 2020; 6:eaba1142. [PMID: 32685678 PMCID: PMC7343378 DOI: 10.1126/sciadv.aba1142] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 05/22/2020] [Indexed: 06/07/2023]
Abstract
Invar-behavior occurring in many magnetic materials has long been of interest to materials science. Here, we show not only invar behavior of a continuous film of FePt but also even negative thermal expansion of FePt nanograins upon equilibrium heating. Yet, both samples exhibit pronounced transient expansion upon laser heating in femtosecond x-ray diffraction experiments. We show that the granular microstructure is essential to support the contractive out-of-plane stresses originating from in-plane expansion via the Poisson effect that add to the uniaxial contractive stress driven by spin disorder. We prove the spin contribution by saturating the magnetic excitations with a first laser pulse and then detecting the purely expansive response to a second pulse. The contractive spin stress is reestablished on the same 100-ps time scale that we observe for the recovery of the ferromagnetic order. Finite-element modeling of the mechanical response of FePt nanosystems confirms the morphology dependence of the dynamics.
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Affiliation(s)
- A. von Reppert
- Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany
| | - L. Willig
- Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Wilhelm-Conrad-12 Röntgen Campus, BESSY II, Albert-Einstein-Str. 15, 12489 Berlin, Germany
| | - J.-E. Pudell
- Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Wilhelm-Conrad-12 Röntgen Campus, BESSY II, Albert-Einstein-Str. 15, 12489 Berlin, Germany
| | - S. P. Zeuschner
- Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Wilhelm-Conrad-12 Röntgen Campus, BESSY II, Albert-Einstein-Str. 15, 12489 Berlin, Germany
| | - G. Sellge
- Institut für Physik, Technische Universität Chemnitz, Reichenhainer Str. 70, 09126 Chemnitz, Germany
- Institut für Ionenstrahlphysik und Materialforschung, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstrasse 400, 01328 Dresden, Germany
| | - F. Ganss
- Institut für Physik, Technische Universität Chemnitz, Reichenhainer Str. 70, 09126 Chemnitz, Germany
| | - O. Hellwig
- Institut für Physik, Technische Universität Chemnitz, Reichenhainer Str. 70, 09126 Chemnitz, Germany
- Institut für Ionenstrahlphysik und Materialforschung, Helmholtz-Zentrum Dresden-Rossendorf, Bautzner Landstrasse 400, 01328 Dresden, Germany
| | - J. A. Arregi
- CEITEC BUT, Brno University of Technology, Purkyňova 123, 612 00 Brno, Czechia
| | - V. Uhlíř
- CEITEC BUT, Brno University of Technology, Purkyňova 123, 612 00 Brno, Czechia
- Institute of Physical Engineering, Brno University of Technology, Technická 2, 616 69 Brno, Czechia
| | - A. Crut
- FemtoNanoOptics Group, Institut Lumière Matière, Université de Lyon, CNRS-Université Lyon 1, 69622 Villeurbanne, France
| | - M. Bargheer
- Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Wilhelm-Conrad-12 Röntgen Campus, BESSY II, Albert-Einstein-Str. 15, 12489 Berlin, Germany
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16
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von Reppert A, Mattern M, Pudell JE, Zeuschner SP, Dumesnil K, Bargheer M. Unconventional picosecond strain pulses resulting from the saturation of magnetic stress within a photoexcited rare earth layer. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2020; 7:024303. [PMID: 32232076 PMCID: PMC7101248 DOI: 10.1063/1.5145315] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 03/09/2020] [Indexed: 06/07/2023]
Abstract
Optical excitation of spin-ordered rare earth metals triggers a complex response of the crystal lattice since expansive stresses from electron and phonon excitations compete with a contractive stress induced by spin disorder. Using ultrafast x-ray diffraction experiments, we study the layer specific strain response of a dysprosium film within a metallic heterostructure upon femtosecond laser-excitation. The elastic and diffusive transport of energy to an adjacent, non-excited detection layer clearly separates the contributions of strain pulses and thermal excitations in the time domain. We find that energy transfer processes to magnetic excitations significantly modify the observed conventional bipolar strain wave into a unipolar pulse. By modeling the spin system as a saturable energy reservoir that generates substantial contractive stress on ultrafast timescales, we can reproduce the observed strain response and estimate the time- and space dependent magnetic stress. The saturation of the magnetic stress contribution yields a non-monotonous total stress within the nanolayer, which leads to unconventional picosecond strain pulses.
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Affiliation(s)
- A. von Reppert
- Institut für Physik & Astronomie, Universität Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany
| | - M. Mattern
- Institut für Physik & Astronomie, Universität Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany
| | | | | | - K. Dumesnil
- Institut Jean Lamour (UMR CNRS 7198), Université Lorraine, 54000 Nancy, France
| | - M. Bargheer
- Author to whom correspondence should be addressed:
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17
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Spetzler B, Golubeva EV, Müller C, McCord J, Faupel F. Frequency Dependency of the Delta-E Effect and the Sensitivity of Delta-E Effect Magnetic Field Sensors. SENSORS 2019; 19:s19214769. [PMID: 31684054 PMCID: PMC6864840 DOI: 10.3390/s19214769] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 10/29/2019] [Accepted: 10/31/2019] [Indexed: 02/01/2023]
Abstract
In recent years the delta-E effect has been used for detecting low frequency and low amplitude magnetic fields. Delta-E effect sensors utilize a forced mechanical resonator that is detuned by the delta-E effect upon application of a magnetic field. Typical frequencies of operation are from several kHz to the upper MHz regime. Different models have been used to describe the delta-E effect in those devices, but the frequency dependency has mainly been neglected. With this work we present a simple description of the delta-E effect as a function of the differential magnetic susceptibility χ of the magnetic material. We derive an analytical expression for χ that permits describing the frequency dependency of the delta-E effect of the Young’s modulus and the magnetic sensitivity. Calculations are compared with measurements on soft-magnetic (Fe90Co10)78Si12B10 thin films. We show that the frequency of operation can have a strong influence on the delta-E effect and the magnetic sensitivity of delta-E effect sensors. Overall, the delta-E effect reduces with increasing frequency and results in a stiffening of the Young’s modulus above the ferromagnetic resonance frequency. The details depend on the Gilbert damping. Whereas for large Gilbert damping the sensitivity continuously decreases with frequency, typical damping values result in an amplification close to the ferromagnetic resonance frequency.
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18
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Chen Z, Wang LW. Role of initial magnetic disorder: A time-dependent ab initio study of ultrafast demagnetization mechanisms. SCIENCE ADVANCES 2019; 5:eaau8000. [PMID: 31259238 PMCID: PMC6598756 DOI: 10.1126/sciadv.aau8000] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 05/22/2019] [Indexed: 05/23/2023]
Abstract
Despite more than 20 years of development, the underlying physics of the laser-induced demagnetization process is still debated. We present a fast, real-time time-dependent density functional theory (rt-TDDFT) algorithm together with the phenomenological atomic Landau-Lifshitz-Gilbert model to investigate this problem. Our Hamiltonian considers noncollinear magnetic moment, spin-orbit coupling (SOC), electron-electron, electron-phonon, and electron-light interactions. The algorithm for time evolution achieves hundreds of times of speedup enabling calculation of large systems. Our simulations yield a demagnetization rate similar to experiments. We found that (i) the angular momentum flow from light to the system is not essential and the spin Zeeman effect is negligible. (ii) The phonon can play a role but is not essential. (iii) The initial spin disorder and the self-consistent update of the electron-electron interaction play dominant roles and enhance the demagnetization to the experimentally observed rate. The spin disorder connects the electronic structure theory with the phenomenological three-temperature model.
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19
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Chen J, Bovensiepen U, Eschenlohr A, Müller T, Elliott P, Gross EKU, Dewhurst JK, Sharma S. Competing Spin Transfer and Dissipation at Co/Cu(001) Interfaces on Femtosecond Timescales. PHYSICAL REVIEW LETTERS 2019; 122:067202. [PMID: 30822073 DOI: 10.1103/physrevlett.122.067202] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 11/28/2018] [Indexed: 05/23/2023]
Abstract
By combining interface-sensitive nonlinear magneto-optical experiments with femtosecond time resolution and ab initio time-dependent density functional theory, we show that optically excited spin dynamics at Co/Cu(001) interfaces proceeds via spin-dependent charge transfer and back transfer between Co and Cu. This ultrafast spin transfer competes with dissipation of spin angular momentum mediated by spin-orbit coupling already on sub 100 fs timescales. We thereby identify the fundamental microscopic processes during laser-induced spin transfer at a model interface for technologically relevant ferromagnetic heterostructures.
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Affiliation(s)
- J Chen
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, Lotharstraße 1, 47057 Duisburg, Germany
| | - U Bovensiepen
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, Lotharstraße 1, 47057 Duisburg, Germany
| | - A Eschenlohr
- Faculty of Physics and Center for Nanointegration (CENIDE), University of Duisburg-Essen, Lotharstraße 1, 47057 Duisburg, Germany
| | - T Müller
- Theory Department, Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany
| | - P Elliott
- Theory Department, Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany
| | - E K U Gross
- Theory Department, Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany
| | - J K Dewhurst
- Theory Department, Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany
| | - S Sharma
- Theory Department, Max Planck Institute of Microstructure Physics, Weinberg 2, 06120 Halle, Germany and Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, Max-Born-Strasse 2A, 12489 Berlin, Germany
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20
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Rossi L, Gerritsen JW, Nelemans L, Khajetoorians AA, Bryant B. An ultra-compact low temperature scanning probe microscope for magnetic fields above 30 T. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:113706. [PMID: 30501346 DOI: 10.1063/1.5046578] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 10/18/2018] [Indexed: 06/09/2023]
Abstract
We present the design of a highly compact high field scanning probe microscope (HF-SPM) for operation at cryogenic temperatures in an extremely high magnetic field, provided by a water-cooled Bitter magnet able to reach 38 T. The HF-SPM is 14 mm in diameter: an Attocube nano-positioner controls the coarse approach of a piezoresistive atomic force microscopy cantilever to a scanned sample. The Bitter magnet constitutes an extreme environment for scanning probe microscopy (SPM) due to the high level of vibrational noise; the Bitter magnet noise at frequencies up to 300 kHz is characterized, and noise mitigation methods are described. The performance of the HF-SPM is demonstrated by topographic imaging and noise measurements at up to 30 T. Additionally, the use of the SPM as a three-dimensional dilatometer for magnetostriction measurements is demonstrated via measurements on a magnetically frustrated spinel sample.
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Affiliation(s)
- L Rossi
- High Field Magnet Laboratory (HFML-EMFL), Radboud University, Nijmegen, The Netherlands
| | - J W Gerritsen
- Institute of Molecules and Materials, Radboud University, Nijmegen, The Netherlands
| | - L Nelemans
- High Field Magnet Laboratory (HFML-EMFL), Radboud University, Nijmegen, The Netherlands
| | - A A Khajetoorians
- Institute of Molecules and Materials, Radboud University, Nijmegen, The Netherlands
| | - B Bryant
- High Field Magnet Laboratory (HFML-EMFL), Radboud University, Nijmegen, The Netherlands
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21
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Layer specific observation of slow thermal equilibration in ultrathin metallic nanostructures by femtosecond X-ray diffraction. Nat Commun 2018; 9:3335. [PMID: 30127415 PMCID: PMC6102217 DOI: 10.1038/s41467-018-05693-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 05/18/2018] [Indexed: 11/29/2022] Open
Abstract
Ultrafast heat transport in nanoscale metal multilayers is of great interest in the context of optically induced demagnetization, remagnetization and switching. If the penetration depth of light exceeds the bilayer thickness, layer-specific information is unavailable from optical probes. Femtosecond diffraction experiments provide unique experimental access to heat transport over single digit nanometer distances. Here, we investigate the structural response and the energy flow in the ultrathin double-layer system: gold on ferromagnetic nickel. Even though the excitation pulse is incident from the Au side, we observe a very rapid heating of the Ni lattice, whereas the Au lattice initially remains cold. The subsequent heat transfer from Ni to the Au lattice is found to be two orders of magnitude slower than predicted by the conventional heat equation and much slower than electron–phonon coupling times in Au. We present a simplified model calculation highlighting the relevant thermophysical quantities. Heat transport in ultrathin metal layers is important for potential applications in optical‐magnetic switching, but difficult to access experimentally. Here, the authors use ultrafast X‐ray diffraction to directly probe and explain unexpected time‐dependent transport behavior in Au–Ni nanolayers.
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22
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Pressacco F, Uhlíř V, Gatti M, Nicolaou A, Bendounan A, Arregi JA, Patel SKK, Fullerton EE, Krizmancic D, Sirotti F. Laser induced phase transition in epitaxial FeRh layers studied by pump-probe valence band photoemission. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2018; 5:034501. [PMID: 29888296 PMCID: PMC5966309 DOI: 10.1063/1.5027809] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 04/27/2018] [Indexed: 06/08/2023]
Abstract
We use time-resolved X-ray photoelectron spectroscopy to probe the electronic and magnetization dynamics in FeRh films after ultrafast laser excitations. We present experimental and theoretical results which investigate the electronic structure of FeRh during the first-order phase transition, identifying a clear signature of the magnetic phase. We find that a spin polarized feature at the Fermi edge is a fingerprint of the magnetic status of the system that is independent of the long-range ferromagnetic alignment of the magnetic domains. We use this feature to follow the phase transition induced by a laser pulse in a pump-probe experiment and find that the magnetic transition occurs in less than 50 ps and reaches its maximum in 100 ps.
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Affiliation(s)
| | | | | | - Alessandro Nicolaou
- Synchrotron SOLEIL, Saint-Aubin, BP 48, F-91192 Gif-sur-Yvette Cedex, France
| | - Azzedine Bendounan
- Synchrotron SOLEIL, Saint-Aubin, BP 48, F-91192 Gif-sur-Yvette Cedex, France
| | - Jon Ander Arregi
- CEITEC BUT, Brno University of Technology, Purkyňova 123, 612 00 Brno, Czech Republic
| | - Sheena K K Patel
- Center for Memory and Recording Research, University of California, San Diego, La Jolla, California 92093-0401, USA
| | - Eric E Fullerton
- Center for Memory and Recording Research, University of California, San Diego, La Jolla, California 92093-0401, USA
| | - Damjan Krizmancic
- Instituto Officina dei Materiali (IOM)-CNR, Laboratorio TASC, in Area Science Park S.S.14, Km 163.5, I34149 Trieste, Italy
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