Speaker
Description
Affiliation: Nanostructures and Ultrafast X-Ray Science, Laboratory for Solid State Physics, ETH Zurich
Email: cmichellod@student.ethz.ch
Authors : Carole Michellod, Indrani Dey, Isabelle Bolliers, Alessandro Colombo, Ehsan
Hassanpour-Yesaghi, Linos Hecht, Bruno Langbehn, Jannis Lehmann, Mario Sauppe,
Nora Sigrist, Janick Schrodt, Lea Schuepke, José Gòmez Torres, Frederic Ussling, Simon
Wächter, Björn Senfftleben and Daniela Rupp
Abstract : Single-particle coherent diffraction imaging (CDI) is a powerful imaging
method that enable to retrieve information about the structure and dynamics of
individual nanoparticles in free-flight from a diffraction pattern obtained in a single
illumination. High harmonics generation (HHG) sources producing highly intense
extreme ultraviolet (XUV) pulses has made single-shot single-particle coherent
diffraction imaging possible in a laboratory environment [1]. Recently, ultrafast electron
dynamics in individual helium nanodroplets have been traced with time-resolved HHG-
based CDI [2]. Accessing the ultrafast laser-driven electronic properties requires
spectral information of the diffracted light, as the interaction between the XUV and the
imaged nanoparticles is reflected in the spectral distribution. An exact shot-to-shot
knowledge of the diffracted spectrum is also of great importance for structural
reconstruction, since the fine details in the patterns are blurred by multiple harmonics
contributions. Here we present the development and first results of a simultaneous
diffraction imaging and diffraction spectroscopy experiment with helium nanodroplets.
We observe a change in the relative contributions of the different harmonics in the
diffracted spectrum of the XUV light, depending on the intensity of an NIR pulse
simultaneously illuminating the helium droplets, indicating transient laser-induced
changes in the optical properties of the helium droplets. Accessing the spectral
distribution of the diffracted light togerher with the single-shot diffraction patterns can
also unlock new opportunities for electron dynamics studies in FEL based experiments.
[1] Rupp, D., Monserud, N., Langbehn, B. et al. Coherent diffractive imaging of single
helium nanodroplets with a high harmonic generation source. Nat Commun 8, 493
(2017)
[2] Schäfer-Zimmermann J, Scheven T, Colombo A, Kolatzki K, Kruse B, Langbehn B,
Möller T, Monserud N, Sauppe M, Schütte B, et al. Laser-Induced Transient Opacity in
Helium Nanodroplets Probed by Single-Shot Coherent Diffraction. Ultrafast Sci. 6, 0146
(2026) DOI :10.34133/ultrafastscience.0146