Visualizing light elements by attosecond X-ray scattering

• Project/Area Number: 22KK0233
• Research Category: Fund for the Promotion of Joint International Research (Fostering Joint International Research (A))
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 80040:Quantum beam science-related
• Research Institution: Institute of Physical and Chemical Research
• Principal Investigator: Inoue Ichiro 国立研究開発法人理化学研究所, 放射光科学研究センター, 研究員 (30783401)
• Project Period (FY): 2023 – 2024
• Project Status: Completed (Fiscal Year 2024)
• Budget Amount: ¥13,000,000 (Direct Cost: ¥10,000,000、Indirect Cost: ¥3,000,000)
• Keywords: アト秒 / 非線形蛍光 / 無損傷計測 / 禁制反射 / アト秒パルス / 非線形光学効果 / X線自由電子レーザー / X線回折 / 無損傷構造解析 / 構造解析 / アト秒科学 / 電子加速器 / X線構造解析

Outline of Research at the Start

本研究では、従来のX線構造解析法では困難であった「軽元素の可視化」を、ナノサイズに集光したアト秒X線自由電子レーザー(XFEL)を用いることで実現する。基課題で開発中のX線ナノ集光光学系に、ナノ集光したアト秒XFELを組み合わせて試料からのX線散乱を測定する。このような高強度XFELの照射下では、原子番号が大きな元素の散乱能は光電効果で作られた内殻ホールのために著しく低下するため、軽元素からの散乱信号を相対的に増幅することができる。この原理を用いて軽元素の密度分布や空間配置を決定することによって、「X線構造解析法では軽元素が見えづらい」というこれまでの常識を覆すことを目指す。

Outline of Final Research Achievements

By combining the nanofocusing mirror with attosecond XFEL pulses generated at XFEL facilities in the United States (Linac Coherent Light Source) and Germany (European XFEL), we explored nonlinear X-ray optical effects and investigated damage-free structure determination.

Analysis of the nonlinear signals confirmed that XFEL pulses with pulse durations of several hundred attoseconds were indeed generated. Diffraction measurement of silicon revealed that valence electron excitation during the pulse was significantly suppressed when using attosecond pulses, whereas substantial excitation occurred with femtosecond pulses.

Academic Significance and Societal Importance of the Research Achievements

X線が物質によって散乱される様子を利用して結晶材料の原子スケールの構造を明らかにするX線構造解析法は、現代の物質科学や生命科学において不可欠なツールとして広く用いられている。本研究では、アト秒X線パルスを利用することで、X線によって生じる構造変化や電子励起といった試料へのダメージを大幅に抑制できることを明らかにした。この成果は、アト秒パルスを用いることで、従来よりも高強度なX線を利用しながら試料の構造情報を取得できる可能性を示唆しており、タンパク質材料やナノ結晶試料の構造および電子状態の精密計測への応用が期待される。

Research Products

• [Int'l Joint Research] University of Hamburg(ドイツ) (2024)
  • Year and Date: 2024-03-18
• [Journal Article] Nanofocused attosecond hard x-ray free-electron laser with intensity exceeding 10^19 W/cm^2 (2025)
  • Author(s): Inoue Ichiro、Sato Takahiro、Robles River et al.
  • Journal Title: Optica Volume: 12 Issue: 3 Pages: 309-309
  • DOI: 10.1364/optica.554954
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] High-intensity X-ray pump-monochromatic X-ray probe technique across time zero (2025)
  • Author(s): Inoue Ichiro、Osaka Taito、Tkachenko Victor、Hara Toru、Kapcia Konrad J.、Inubushi Yuichi、Kawaguchi Shogo、Yamada Jumpei、Nishibori Eiji、Yabashi Makina、Ziaja Beata
  • Journal Title: Optica Volume: 12 Issue: 4 Pages: 530-530
  • DOI: 10.1364/optica.555433
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Interplay of thermal and nonthermal effects in x-ray-induced ultrafast melting (2024)
  • Author(s): I. Inoue, V. Tkachenko, Y. Kubota, F. Dorchies, T. Hara, H. Hoppner, Y. Inubushi, K. J. Kapcia, H. J. Lee, V. Lipp, P. Martinez, E. Nishibori, T. Osaka, S. Toleikis, J. Yamada, M. Yabashi, B. Ziaja, P. A. Heimann
  • Journal Title: Physical Review B Volume: 110 Issue: 10 Pages: 100102-100103
  • DOI: 10.1103/physrevb.110.l100102
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Terawatt-attosecond hard X-ray free-electron laser at high repetition rate (2024)
  • Author(s): Yan Jiawei、Qin Weilun、Chen Ye、Decking Winfried、Dijkstal Philipp、Guetg Marc、Inoue Ichiro、Kujala Naresh、Liu Shan、Long Tianyun、Mirian Najmeh、Geloni Gianluca
  • Journal Title: Nature Photonics Volume: 18 Issue: 12 Pages: 1293-1298
  • DOI: 10.1038/s41566-024-01566-0
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Perspective for in-volume machining of solid materials by undersurface focusing of x-ray pulses (2024)
  • Author(s): Inoue Ichiro、Ziaja Beata
  • Journal Title: Journal of Physics B: Atomic, Molecular and Optical Physics Volume: 57 Issue: 19 Pages: 192501-192501
  • DOI: 10.1088/1361-6455/ad7551
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Extreme focusing of hard X-ray free-electron laser pulses enables 7 nm focus width and 1022 W cm^-2 intensity (2024)
  • Author(s): Yamada Jumpei、Matsuyama Satoshi、Inoue Ichiro、Osaka Taito、Inoue Takato、Nakamura Nami、Tanaka Yuto、Inubushi Yuichi、Yabuuchi Toshinori、Tono Kensuke、Tamasaku Kenji、Yumoto Hirokatsu、Koyama Takahisa、Ohashi Haruhiko、Yabashi Makina、Yamauchi Kazuto
  • Journal Title: Nature Photonics Volume: - Issue: 7 Pages: 685-690
  • DOI: 10.1038/s41566-024-01411-4
  • Peer Reviewed / Open Access
• [Journal Article] Femtosecond Reduction of Atomic Scattering Factors Triggered by Intense X-Ray Pulse (2023)
  • Author(s): Inoue Ichiro、Yamada Jumpei、Kapcia Konrad J.、Stransky Michal、Tkachenko Victor、Jurek Zoltan、Inoue Takato、Osaka Taito、Inubushi Yuichi、Ito Atsuki、Tanaka Yuto、Matsuyama Satoshi、Yamauchi Kazuto、Yabashi Makina、Ziaja Beata
  • Journal Title: Physical Review Letters Volume: 131 Issue: 16
  • DOI: 10.1103/physrevlett.131.163201
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Seeded stimulated X-ray emission at 5.9keV (2023)
  • Author(s): M.D.Doyle, A.Halavanau, Y.Zhang, Y.Michine, J.Everts, F.Fuller, R.Alonso-Mori, M.Yabashi, I.Inoue, T.Osaka, J.Yamada, Y.Inubushi, T.Hara, J.Kern, J.Yano, V.K.Yachandra, N.Rohringer, H.Yoneda, T.Kroll, C.Pellegrini, and U.Bergmann
  • Journal Title: Optica Volume: 10 Issue: 4 Pages: 513-519
  • DOI: 10.1364/optica.485989
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Modeling Femtosecond Reduction of Atomic Scattering Factors in X-ray-Excited Silicon with Boltzmann Kinetic Equations (2023)
  • Author(s): Ziaja Beata、Stransky Michal、Kapcia Konrad J.、Inoue Ichiro
  • Journal Title: Atoms Volume: 11 Issue: 12 Pages: 154-154
  • DOI: 10.3390/atoms11120154
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Pair Distribution Function from Liquid Jet Nanoparticle Suspension using Femtosecond X‐ray Pulses (2023)
  • Author(s): Stockler Lise Joost、Christensen Rasmus Stubkjar、Klove Magnus、Bertelsen Andreas Dueholm、Borup Anders B?k、Krause Lennard、Takahashi Seiya、Fujita Tomoki、Kasai Hidetaka、Inoue Ichiro、Nishibori Eiji、Iversen Bo Brummerstedt
  • Journal Title: ChemPhysChem Volume: 24 Issue: 23
  • DOI: 10.1002/cphc.202300407
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Non-thermal structural transformation of diamond driven by x-rays (2023)
  • Author(s): Heimann Philip、Hartley Nicholas J.、Inoue Ichiro、Tkachenko Victor、Antoine Andre、Dorchies Fabien、Falcone Roger、Gaudin J?r?me、H?ppner Hauke、Inubushi Yuichi、Kapcia Konrad J.、Lee Hae Ja、Lipp Vladimir、Martinez Paloma、Medvedev Nikita、Tavella Franz et al.
  • Journal Title: Structural Dynamics Volume: 10 Issue: 5
  • DOI: 10.1063/4.0000193
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] Observation of nonlinear X-ray effects with attosecond hard X-ray pulses (2025)
  • Author(s): Ichiro Inoue
  • Organizer: European XFEL Users' meeting
  • Int'l Joint Research / Invited
• [Presentation] Exploring nonlinear X-ray effects with attosecond pulses (2025)
  • Author(s): Ichiro Inoue
  • Organizer: Ringberg workshop on Science with FELs
  • Int'l Joint Research / Invited
• [Presentation] Future perspectives of X-ray free-electron lasers (2025)
  • Author(s): Ichiro Inoue
  • Organizer: ALPS2025
  • Int'l Joint Research / Invited
• [Presentation] Harnessing cohenrence in fluorescence for photon diagnostics and future X-ray sources (2024)
  • Author(s): Ichiro Inoue
  • Organizer: Coherence2024
  • Int'l Joint Research / Invited
• [Presentation] Nonlinearity in X-Ray Scattering at High Intensity (2023)
  • Author(s): Ichiro Inoue
  • Organizer: Gordon Research Conference, X-ray Science
  • Int'l Joint Research / Invited
• [Remarks] RIKEN research
  • URL: https://www.riken.jp/en/news_pubs/research_news/rr/20240319_2/index.html
• [Remarks] X線回折に潜む非線形性の発見
  • URL: https://www.riken.jp/press/2023/20231018_1/index.html