Unconventional picosecond strain pulses resulting from the saturation of magnetic stress within a photoexcited rare earth layer
- 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 aOptical 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.…
Verfasserangaben: | Alexander von ReppertORCiDGND, Maximilian MatternORCiD, Jan-Etienne PudellORCiDGND, Steffen Peer ZeuschnerORCiDGND, Karine DumesnilORCiD, Matias BargheerORCiDGND |
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URN: | urn:nbn:de:kobv:517-opus4-469350 |
DOI: | https://doi.org/10.25932/publishup-46935 |
ISSN: | 1866-8372 |
Titel des übergeordneten Werks (Deutsch): | Postprints der Universität Potsdam : Mathematisch Naturwissenschaftliche Reihe |
Schriftenreihe (Bandnummer): | Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe (899) |
Publikationstyp: | Postprint |
Sprache: | Englisch |
Datum der Erstveröffentlichung: | 19.05.2020 |
Erscheinungsjahr: | 2020 |
Veröffentlichende Institution: | Universität Potsdam |
Datum der Freischaltung: | 19.05.2020 |
Freies Schlagwort / Tag: | Crystal lattices; Femtosecond lasers; Heterostructures; Phonons; Photoexcitations; Strain measurement; Thermal effects; Ultrafast X-rays |
Ausgabe: | 899 |
Seitenanzahl: | 15 |
Quelle: | Structural Dynamics 7 (2020) 024303 DOI: 10.1063/1.5145315 |
Organisationseinheiten: | Mathematisch-Naturwissenschaftliche Fakultät |
DDC-Klassifikation: | 5 Naturwissenschaften und Mathematik / 50 Naturwissenschaften / 500 Naturwissenschaften und Mathematik |
5 Naturwissenschaften und Mathematik / 53 Physik / 530 Physik | |
Peer Review: | Referiert |
Publikationsweg: | Open Access |
Lizenz (Deutsch): | CC-BY - Namensnennung 4.0 International |
Externe Anmerkung: | Bibliographieeintrag der Originalveröffentlichung/Quelle |