Applied Sciences (Feb 2023)

Ionization of Xenon Clusters by a Hard X-ray Laser Pulse

  • Yoshiaki Kumagai,
  • Weiqing Xu,
  • Kazuki Asa,
  • Toshiyuki Hiraki Nishiyama,
  • Koji Motomura,
  • Shin-ichi Wada,
  • Denys Iablonskyi,
  • Subhendu Mondal,
  • Tetsuya Tachibana,
  • Yuta Ito,
  • Tsukasa Sakai,
  • Kenji Matsunami,
  • Takayuki Umemoto,
  • Christophe Nicolas,
  • Catalin Miron,
  • Tadashi Togashi,
  • Kanade Ogawa,
  • Shigeki Owada,
  • Kensuke Tono,
  • Makina Yabashi,
  • Hironobu Fukuzawa,
  • Kiyonobu Nagaya,
  • Kiyoshi Ueda

DOI
https://doi.org/10.3390/app13042176
Journal volume & issue
Vol. 13, no. 4
p. 2176

Abstract

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Ultrashort pulse X-ray free electron lasers (XFFLs) provided us with an unprecedented regime of X-ray intensities, revolutionizing ultrafast structure determination and paving the way to the novel field of non-linear X-ray optics. While pioneering studies revealed the formation of a nanoplasma following the interaction of an XFEL pulse with nanometer-scale matter, nanoplasma formation and disintegration processes are not completely understood, and the behavior of trapped electrons in the electrostatic potential of highly charged species is yet to be decrypted. Here we report the behavior of the nanoplasma created by a hard X-ray pulse interacting with xenon clusters by using electron and ion spectroscopy. To obtain a deep insight into the formation and disintegration of XFEL-ignited nanoplasma, we studied the XFEL-intensity and cluster-size dependencies of the ionization dynamics. We also present the time-resolved data obtained by a near-infrared (NIR) probe pulse in order to experimentally track the time evolution of plasma electrons distributed in the XFEL-ignited nanoplasma. We observed an unexpected time delay dependence of the ion yield enhancement due to the NIR pulse heating, which demonstrates that the plasma electrons within the XFEL-ignited nanoplasma are inhomogeneously distributed in space.

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