Ultraintense 7 nm focusing of hard X-ray free-electron laser at SACLA
We have developed a 7 nm XFEL focusing system capable of achieving an intensity of 10²² W/cm², utilizing advanced Kirkpatrick–Baez mirrors with reduced comatic aberrations. Accurate focus characterization, particularly for astigmatism, is essential but challenging for such low-order aberrations. To address this issue, we employed three complementary methods: grating-based wavefront sensing, ptychographic probe reconstruction, and speckle interferometry. These techniques collectively enabled high-accuracy focus measurement. The ultraintense XFEL focus has facilitated groundbreaking observations, including the first detection of X-ray three-photon absorption in recent experiments.
Authors
- Daisetsu Toh (ORCID: https://orcid.org/0000-0003-3880-4154)
- Taito Osaka (ORCID: https://orcid.org/0000-0003-0545-9737)
- Ichiro Inoue (ORCID: https://orcid.org/0009-0008-0423-1347)
- Jumpei Yamada (ORCID: https://orcid.org/0000-0002-5476-4327)
- Yasuhisa Sano (ORCID: https://orcid.org/0000-0002-1767-922X)
- Gota Yamaguchi (ORCID: https://orcid.org/0000-0003-4305-807X)
- Yuichi Inubushi (ORCID: https://orcid.org/0000-0003-1608-3819)
- Kenji Tamasaku (ORCID: https://orcid.org/0000-0003-1440-0518)
- Kazuto Yamauchi (ORCID: https://orcid.org/0000-0001-7831-9423)
- Makina Yabashi (ORCID: https://orcid.org/0000-0002-2472-1684)
Institutions
- SPring-8 (JP)
- Japan Synchrotron Radiation Research Institute (JP)
- The University of Osaka (JP)
Publication Details
- Published
- 2025-06-06
- DOI
- https://doi.org/10.1117/12.3056080
- Primary Topic
- Particle Accelerators and Free-Electron Lasers
- Type
- article
- Field-Weighted Citation Impact
- 0.00