TY  - JOUR
AU  - Ding, Thomas
AU  - Rebholz, Marc
AU  - Aufleger, Lennart
AU  - Hartmann, Maximilian
AU  - Stooß, Veit
AU  - Magunia, Alexander
AU  - Birk, Paul
AU  - Borisova, Gergana Dimitrova
AU  - da Costa Castanheira, Carina
AU  - Rupprecht, Patrick
AU  - Mi, Yonghao
AU  - Gaumnitz, Thomas
AU  - Loh, Zhi-Heng
AU  - Roling, Sebastian
AU  - Butz, Marco
AU  - Zacharias, Helmut
AU  - Düsterer, Stefan
AU  - Treusch, Rolf
AU  - Ott, Christian
AU  - Pfeifer, Thomas
TI  - XUV pump–XUV probe transient absorption spectroscopy at FELs
JO  - Faraday discussions
VL  - 228
SN  - 1364-5498
CY  - Cambridge [u.a.]
PB  - Soc.
M1  - PUBDB-2021-02839
SP  - 519 - 536
PY  - 2021
AB  - The emergence of ultra-intense extreme-ultraviolet (XUV) and X-ray free-electron lasers (FELs) has opened the door for the experimental realization of non-linear XUV and X-ray spectroscopy techniques. Here we demonstrate an experimental setup for an all-XUV transient absorption spectroscopy method for gas-phase targets at the FEL. The setup combines a high spectral resolving power of E/ΔE ≈ 1500 with sub-femtosecond interferometric resolution, and covers a broad XUV photon-energy range between approximately 20 and 110 eV. We demonstrate the feasibility of this setup firstly on a neon target. Here, we intensity- and time-resolve key aspects of non-linear XUV-FEL light–matter interactions, namely the non-resonant ionization dynamics and resonant coupling dynamics of bound states, including XUV-induced Stark shifts of energy levels. Secondly, we show that this setup is capable of tracking the XUV-initiated dissociation dynamics of small molecular targets (oxygen and diiodomethane) with site-specific resolution, by measuring the XUV transient absorption spectrum. In general, benefitting from a single-shot detection capability, we show that the setup and method provides single-shot phase-locked XUV pulse pairs. This lays the foundation to perform, in the future, experiments as a function of the XUV interferometric time delay and the relative phase, which enables advanced coherent non-linear spectroscopy schemes in the XUV and X-ray spectral range.
LB  - PUB:(DE-HGF)16
C6  - 33575691
UR  - <Go to ISI:>//WOS:000664793300026
DO  - DOI:10.1039/D0FD00107D
UR  - https://bib-pubdb1.desy.de/record/459956
ER  -