Speaker
Peter Gaal
(University of Potsdam, Institut for Physics and Astronomy)
Description
We report on the first time-resolved X-ray diffraction experiment at the EDR beamline at BESSY II performed on epitaxial La0.8Sr0.2MnO3 (LSMO) and SrTiO3 (STO) superlattices grown on single crystal STO substrate.
A Ti:Sapphire laser operating at 208 kHz frequency with 350 fs pulse duration was used as a pump beam. The X-ray pulses from a bending magnet were monochromotized using a single Ge crystal and used as a probe. Superlattice diffraction peak profiles were recorded as a function of pump-probe delay. The measured peak shift, which is proportional to the strain in the superlattice, is a measure of the thermal expansion. Heat transport in both the superlattice and the substrate has been studied on timescales of 50 ps to 4 µs. The experimental results agree well with theoretical simulations of heat transport in such systems. The transient thermal expansion was determined with an accuracy of 10^-7, which corresponds to a temperature rise of 0.01°C.
Author
Peter Gaal
(University of Potsdam, Institut for Physics and Astronomy)
Co-authors
Hengameh Navirian
(Helmholtz-Zentrum Berlin für Materialien und Energie)
Marc Herzog
(University of Potsdam, Institut for Physics and Astronomy)
Matias Bargheer
(University of Potsdam, Institut for Physics and Astronomy)
Roman Shayduk
(Helmholtz-Zentrum Berlin für Materialien und Energie)
Wolfram Leitenberger
(University of Potsdam, Institut for Physics and Astronomy)
Yevgen Goldsteyn
(Helmholtz-Zentrum Berlin für Materialien und Energie)
