Dresden 2026 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 98: Ultrafast electron dynamics at surface and interfaces IV
O 98.3: Vortrag
Freitag, 13. März 2026, 10:15–10:30, TRE/MATH
Ultrafast x-ray sonography: A novel technique to spatially resolve phase heterogeneity on picosecond timescales — •Maximilian Mattern1, Angel Rodriguez-Fernandez2, Roman Shayduk2, Wonhyuk Jo2, Vojtech Uhlir3, Jon Ander Arregi3, Anders Madsen2, Daniel Schick1, and Jan-Etienne Pudell2 — 1Max-Born-Institut, Germany — 2European XFEL, Germany — 3CEITEC BUT, Czech Republic
Laser-induced heterogeneities play an important role for ultrafast dynamics especially of first-order phase transitions due to the phase co-existence during nucleation. However, their probing on picosecond time and nanometer length scales is challenging.
To address this challenge, we introduce ultrafast X-ray sonography. It combines well-established ultrafast hard-X-ray diffraction with a propagating strain pulse as a universal and non-invasive structural marker. The signatures of the strain pulse in the phase-specific lattice dynamics localizes the different phases in both space and time. This non-invasive pump-probe technique can follow the coherent growth and stochastic nucleation of structural domains on picosecond timescales with almost no requirements for sample preparation and is broadly applicable to a broad class of materials, provided that the coexisting phases exhibit distinguishable diffraction signatures. As a benchmark, we apply this approach to the antiferromagnetic-to-ferromagnetic magneto-structural phase transition in FeRh and identify the ferromagnetic phase to nucleate at the surface as columnar domains of approximately 30nm diameter.
Keywords: ultrafast x-ray diffraction; phase transition; phase heterogeneity; FeRh