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RIKEN SPring-8 Center Advanced X-Ray Laser Group

Group Director: Takashi Tanaka (D.Eng.)

Research Summary

Takashi  Tanaka(D.Eng.)

The mission of Advanced X-ray Laser Group is to upgrade the light source performance of SACLA (XFEL: X-ray free electron laser facility) and SPring-8 (large-scale SR: synchrotron radiation facility), which are in operation in RIKEN SPring-8 Center (RSC). We are developing magnetic devices called undulators, which produce intense X-ray laser and highly brilliant SR by deflecting the high energy electron beam. We also explore more advanced XFEL and SR concepts that will open up a new possibility of X-ray science. By promoting these R&Ds, we pursue the goal of enhancing the light source performances of SACLA and SPring-8, and establish an “ultimate X-ray laser facility” in RSC, which eventually leads to creation of a new field of photon science exploiting X-ray lasers.

Main Research Fields

  • Interdisciplinary Science & Engineering

Related Research Fields

  • Mathematical & Physical Sciences
  • Engineering
  • Quantum Beam Science
  • Applied Physics
  • Integrated Engineering


  • free electron laser
  • synchrotron radiation
  • undulator
  • simulation
  • permanent magnet

Selected Publications

    • 1. T. Tanaka, Y. Kida, S. Hashimoto et al.:
      "Experimental demonstration to control the pulse length of coherent undulator radiation by chirped microbunching,"
      Phys. Rev. Lett. 131, 145001 (2023)
    • 2. T. Tanaka, T. Seike, A. Kagamihata et al.:
      "Development of an insertion device selectively operational as a helical/figure-8 undulator,"
      Journal of Synchrotron Radiation 30, 301 (2023)
    • 3. T. Tanaka and P. R. Ribic.:
      "Proposal to generate a pair of intense independently tunable attosecond pulses from undulator radiation,"
      Opt. Lett. 47, 1411 (2022)
    • 41. T. Tanaka.
      "Major upgrade of the synchrotron radiation calculation code SPECTRA,"
      Journal of Synchrotron Radiation 28, 1267 (2021)
    • 5. T. Tanaka and A. Kagamihata.:
      "Thermal demagnetization in in-vacuum undulators and effect of magnetic configuration on choice of magnet grade"
      Nuclear Instruments and Methods in Physics Research Section A, 165112 (2021)
    • 6. T. Tanaka, Y. Kida, R. Kinjo et al.:
      "Development of an undulator with a variable magnetic field profile"
      Journal of Synchrotron Radiation 28, 404-409 (2021)
    • 7. P. R. Ribic and T. Tanaka.:
      "Isolated single-cycle extreme-ultraviolet pulses from undulator radiation"
      Opt. Lett. 45, 5234-5237 (2020)
    • 8. R. Kinjo and T. Tanaka.:
      "Undulator configuration for helicity switching in in-vacuum undulators"
      Phys. Rev. Accel. Beams 23, 020705 (2020)
    • 9. T. Tanaka.:
      "Electron bunch compression with an optical laser"
      Phys. Rev. Accel. Beams 22, 110704 (2019)
    • 10. T. Tanaka and P. R. Ribic.:
      "Shortening the pulse duration in seeded free-electron lasers by chirped microbunching"
      Opt. Express 27, 30875-30892 (2019)

    Recent Research Results

    Lab Members

    Principal investigator

    Takashi Tanaka
    Group Director

    Contact Information

    Structural Biology Facility 311,
    1-1-1 Kouto, Sayo-cho, Sayo-gun
    Hyogo 679-5148, Japan
    Tel: +81-(0)791-58-0802
    Extension: 3806
    Email: ztanaka [at] spring8.or.jp