Matter and Radiation at Extremes, Volume. 6, Issue 3, 034001(2021)

XFEL and HHG interaction with matter: Effects of ultrashort pulses and random spikes

F. B. Rosmej1,2,3,4, V. A. Astapenko3, and E. S. Khramov3
Author Affiliations
  • 1Sorbonne University, Faculty of Science and Engineering, UMR 7605, Case 128, 4 Place Jussieu, F-75252 Paris Cedex 05, France
  • 2LULI, Ecole Polytechnique, CEA, CNRS, Laboratoire pour l’Utilisation des Lasers Intenses, Physique Atomique dans les Plasmas Denses, F-91128 Palaiseau, France
  • 3Moscow Institute of Physics and Technology—MIPT, Institutskii per. 9, Dolgoprudnyi 141700, Russia
  • 4National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Kashirskoe sh. 31, Moscow 115409, Russia
  • show less

    The theory of photoionization describing the interaction of x-ray free-electron laser (XFEL) pulses and high-harmonic-generated (HHG) radiation is generalized to ultrashort laser pulses, where the concept of the standard ionization probability per unit time in Fermi’s golden rule and in Einstein’s theory breaks down. Numerical calculations carried out in terms of a generalized photoionization probability for the total duration of pulses in the near-threshold regime demonstrate essentially nonlinear behavior, while absolute values may change by orders of magnitude for typical XFEL and HHG pulses. XFEL self-amplified spontaneous emission pulses are analyzed to reveal general features of photoionization for random and regular spikes: the dependences of the nonlinear photoionization probability on carrier frequency and spike duration are very similar, allowing an analytical expectation value approach that is valid even when there is only limited knowledge of random and regular parameters. Numerical simulations carried out for typical parameters demonstrate excellent agreement.

    Tools

    Get Citation

    Copy Citation Text

    F. B. Rosmej, V. A. Astapenko, E. S. Khramov. XFEL and HHG interaction with matter: Effects of ultrashort pulses and random spikes[J]. Matter and Radiation at Extremes, 2021, 6(3): 034001

    Download Citation

    EndNote(RIS)BibTexPlain Text
    Save article for my favorites
    Paper Information

    Category: Letters

    Received: Jan. 31, 2021

    Accepted: Feb. 25, 2021

    Published Online: May. 21, 2021

    The Author Email:

    DOI:10.1063/5.0046040

    Topics