We combine the ultrashort pulse duration with the high photon energy provided by FEL and HHG sources to investigate both collective and correlated electron dynamics in nanoparticles using coherent diffractive imaging (CDI) and time-resolved photoelectron and photoion spectroscopy. We aim to spatially resolve at the nanoscale ultrafast electron dynamics in relatively large nanoparticles.
Daniela Rupp, Thomas Fennel, Arnaud Rouzée, Linos Hecht, Katharina Kolatzki, Nils Monserud, Mario Sauppe, Bernd Schütte, Björn Senfftleben, Rico Tanyag, Julian Zimmermann
In this topic, we study the structure and dynamics of single nanoparticles in free flight with coherent diffractive imaging, aiming especially at resolving ultrafast electron dynamics in space and time. Therefore, we employ intense and short XUV pulses from free-electron lasers (FELs) and high harmonic generation sources to measure coherent diffraction images from single nanoparticles and droplets in free flight. The nanoparticle’s structure can be determined from the diffraction images. Even three-dimensional structural information is contained in wide-angle diffraction images obtained in the XUV regime and can be retrieved with forward-fitting procedures. Building on the understanding of the particle’s structure, we are developing and employing novel experimental and analysis approaches based on multicolor-XUV pulses to visualize and trace the (sub-) femtosecond dynamics of the nanoparticle’s electronic structure via the diffraction images.
Bernd Schütte, Thomas Fennel, Arnaud Rouzée
Using intense HHG pulses, we investigate the ionization and relaxation dynamics taking place in van-der-Waals bound dimers and large clusters. The few-femtosecond charging dynamics of extended clusters are mapped using terahertz streaking. XUV-NIR pump-probe schemes are employed to study the electron-ion recombination dynamics as well as the correlated electronic decay (CED) processes that take place in the confined nanoplasma that is formed. Our intense attosecond and femtosecond XUV sources allow us to observe and understand complex processes evolving in these systems on the fastest timescales.