TY  - GEN
A1  - von Reppert, Alexander
A1  - Mattern, Maximilian
A1  - Pudell, Jan-Etienne
A1  - Zeuschner, Steffen Peer
A1  - Dumesnil, Karine
A1  - Bargheer, Matias
T1  - Unconventional picosecond strain pulses resulting from the saturation of magnetic stress within a photoexcited rare earth layer
T2  - Postprints der Universität Potsdam : Mathematisch Naturwissenschaftliche Reihe
N2  - 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.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 899 
KW  - Strain measurement
KW  - Photoexcitations
KW  - Crystal lattices
KW  - Femtosecond lasers
KW  - Thermal effects
KW  - Heterostructures
KW  - Ultrafast X-rays
KW  - Phonons
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-469350
SN  - 1866-8372
IS  - 899
ER  -