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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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Rössle M, Leitenberger W, Reinhardt M, Koç A, Pudell J, Kwamen C, Bargheer M. The time-resolved hard X-ray diffraction endstation KMC-3 XPP at BESSY II. JOURNAL OF SYNCHROTRON RADIATION 2021; 28:948-960. [PMID: 33950003 PMCID: PMC8127367 DOI: 10.1107/s1600577521002484] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 03/05/2021] [Indexed: 06/07/2023]
Abstract
The time-resolved hard X-ray diffraction endstation KMC-3 XPP for optical pump/X-ray probe experiments at the electron storage ring BESSY II is dedicated to investigating the structural response of thin film samples and heterostructures after their excitation with ultrashort laser pulses and/or electric field pulses. It enables experiments with access to symmetric and asymmetric Bragg reflections via a four-circle diffractometer and it is possible to keep the sample in high vacuum and vary the sample temperature between ∼15 K and 350 K. The femtosecond laser system permanently installed at the beamline allows for optical excitation of the sample at 1028 nm. A non-linear optical setup enables the sample excitation also at 514 nm and 343 nm. A time-resolution of 17 ps is achieved with the `low-α' operation mode of the storage ring and an electronic variation of the delay between optical pump and hard X-ray probe pulse conveniently accesses picosecond to microsecond timescales. Direct time-resolved detection of the diffracted hard X-ray synchrotron pulses use a gated area pixel detector or a fast point detector in single photon counting mode. The range of experiments that are reliably conducted at the endstation and that detect structural dynamics of samples excited by laser pulses or electric fields are presented.
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Affiliation(s)
- Matthias Rössle
- Helmholtz-Zentrum Berlin für Materialien und Energie, Wilhelm-Conrad-Röntgen Campus, BESSY II, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - Wolfram Leitenberger
- Institut für Physik and Astronomie, Universität Potsdam, Karl-Liebknecht-Strasse 24–25, 14476 Potsdam, Germany
| | - Matthias Reinhardt
- Helmholtz-Zentrum Berlin für Materialien und Energie, Wilhelm-Conrad-Röntgen Campus, BESSY II, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - Azize Koç
- Helmholtz-Zentrum Berlin für Materialien und Energie, Wilhelm-Conrad-Röntgen Campus, BESSY II, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - Jan Pudell
- Helmholtz-Zentrum Berlin für Materialien und Energie, Wilhelm-Conrad-Röntgen Campus, BESSY II, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - Christelle Kwamen
- Helmholtz-Zentrum Berlin für Materialien und Energie, Wilhelm-Conrad-Röntgen Campus, BESSY II, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - Matias Bargheer
- Helmholtz-Zentrum Berlin für Materialien und Energie, Wilhelm-Conrad-Röntgen Campus, BESSY II, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
- Institut für Physik and Astronomie, Universität Potsdam, Karl-Liebknecht-Strasse 24–25, 14476 Potsdam, Germany
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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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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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