Multispectroscopic Study of Single Xe Clusters Using XFEL Pulses

Abstract

X-ray free-electron lasers (XFELs) deliver ultrashort coherent laser pulses in the X-ray spectral regime, enabling novel investigations into the structure of individual nanoscale samples. In this work, we demonstrate how single-shot small-angle X-ray scattering (SAXS) measurements combined with fluorescence and ion time-of-flight (TOF) spectroscopy can be used to obtain size- and structure-selective evaluation of the light-matter interaction processes on the nanoscale. We recorded the SAXS images of single xenon clusters using XFEL pulses provided by the SPring-8 Angstrom compact free-electron laser (SACLA). The XFEL fluences and the radii of the clusters at the reaction point were evaluated and the ion TOF spectra and fluorescence spectra were sorted accordingly. We found that the XFEL fluence and cluster size extracted from the diffraction patterns showed a clear correlation with the fluorescence and ion TOF spectra. Our results demonstrate the effectiveness of the multispectroscopic approach for exploring laser–matter interaction in the X-ray regime without the influence of the size distribution of samples and the fluence distribution of the incident XFEL pulses.

X-ray induced ultrafast dynamics in atoms, molecules, and clusters: experimental studies at an X-ray free-electron laser facility SACLA and modelling

“…The present findings may validate the 'diffraction-beforedestruction' approach of single bio-macromolecules and protein microcrystals, as long as the hydrogen atoms can be neglected, and also suggest the importance of understanding influences of charge dynamics that occur within the X-ray-pulse duration to the X-ray scattering. We have also been conducting spectroscopic experiments using soft-X-ray FEL [49][50][51] and X-ray diffraction experiments [52][53][54][55] at SACLA, though these attempts were not described in the present review article. We believe that electronic and structural dynamics in various forms of matter will be investigated extensively employing XFELs all over the world and we hope that our attempts described in this article will contribute to such investigations.…”

Science at X-ray Free Electron Lasers

“…Yumoto et al [7] describes state-of-the-art nanofocusing optics for an X-ray FEL generating an extreme intensity of 10 20 W/cm 2 , with a focus size of 210 nm × 210 nm, a pulse duration of 7 fs, and a pulse energy of 150 µJ (1/4 of the pulse energy generated at the light source), using total reflection elliptically figured mirrors, based on Kirkpatrick-Baes geometry. Nishiyama et al [8] established simultaneous measurements of small-angle X-ray scattering, X-ray fluorescent photons, and ions ejected from nanoparticles that consists of xenon atoms and clearly demonstrated correlations of the size of nanoparticles and yields of fluorescence and ions. Claudiu et al [9] employed focused X-ray FEL pulses to generate shock waves in the liquid water microdroplets and determined time-pressure histories of shocks, taking an advantage of very stable operation of SACLA.…”