title: Synchrotron-based ultrafast x-ray diffraction at high repetition rates.
abstract: We present a setup for ultrafast x-ray diffraction (UXRD) based at the storage ring BESSY II, in particular, a pump laser that excites the sample using 250 fs laser-pulses at repetition rates ranging from 208 kHz to 1.25 MHz. We discuss issues connected to the high heat-load and spatio-temporal alignment strategies in the context of a UXRD experiment at high repetition rates. The spatial overlap between laser pump and x-ray probe pulse is obtained with 10 μm precision and transient lattice changes can be recorded with an accuracy of δa/a(0) = 10(-6). We also compare time-resolved x-ray diffraction signals from a laser excited LSMO/STO superlattice with phonon dynamics simulations. From the analysis we determine the x-ray pulse duration to 120 ps in standard operation mode and below 10 ps in low-α mode.
authors: Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Wilhelm-Conrad-Röntgen Campus, BESSY II, Albert-Einstein-Str. 15, 12489 Berlin, Germany.
authors: H
authors: H
authors: Navirian
authors: R
authors: R
authors: Shayduk
authors: W
authors: W
authors: Leitenberger
authors: J
authors: J
authors: Goldshteyn
authors: P
authors: P
authors: Gaal
authors: M
authors: M
authors: Bargheer