X-ray-induced structural and electronic changes in matter captured with unique XFEL schemes

by Ichiro Inoue (RIKEN SPring-8 Center (SACLA) / Universität Hamburg)

Tuesday 25 Jun 2024, 13:00 → 14:00 Europe/Berlin

E1.173 (European XFEL Schenefeld)

X rays have become established as an invaluable probe for gaining an atomic insight into materials, leveraging various kinds of X-ray–matter interaction processes, such as scattering, absorption, and emission of photoelectrons and fluorescence. These interactions were usually weak with the previous generation X-ray source, and therefore it was assumed that X-ray irradiation did not modify the matter. This situation of non-invasive x-ray-matter interaction has been totally changed by the recent advent of X-ray free-electron lasers (XFELs), which can generate high-brilliance X-ray pulses with femtosecond durations. Understanding intense XFEL interactions with matter is essential, not only for the fundamental scientific interest but also for fully exploiting XFEL pulses in material characterization.

  This talk will review our approaches to capturing femtosecond X-ray-matter interactions using unique machine operation modes at SACLA [1-3]. In combination with stable focusing optics [4], we have clarified femtosecond structural and electronic changes in various systems, including diamond [1,5,6], inorganic crystals [7-9], and small-molecule systems. Based on the experimental results, I will discuss the limitations and future challenges of structure determination using intense XFEL pulses.

 

[1] I. Inoue et al., PNAS 113, 1492 (2016).

[2] I. Inoue et al., Nature Photon. 13, 319 (2019).

[3] I. Inoue et al., J. Synchrotron Radiat. 27, 1720 (2020).

[4] H. Yumoto et al., Nature Photon. 7, 43 (2013), H. Mimura et al., Nature Commun. 5, 3539 (2014), J. Yamada et al., Nature Photon (2024).

[5] I. Inoue et al., PRL 126, 117403 (2021).

[6] P. Heimann et al., Struct. Dyn. 10, 054502 (2023).

[7] I. Inoue et al., PRL 128, 223203 (2022).

[8] I. Inoue et al., PRL 131, 163201(2023).

[9] I. Inoue et al., arXiv:2308.14560