Development of X-ray nanobeam optics by precision wavefront control

2023 Fiscal Year Annual Research Report

• Project/Area Number: 21H05004
• Research Institution: Osaka University
• Principal Investigator: 山内 和人 大阪大学, 大学院工学研究科, 教授 (10174575)
• Co-Investigator(Kenkyū-buntansha): 松山 智至 名古屋大学, 工学研究科, 准教授 (10423196) ; 山田 純平 大阪大学, 大学院工学研究科, 助教 (10845027) ; 佐野 泰久 大阪大学, 大学院工学研究科, 准教授 (40252598) ; 藤 大雪 大阪大学, 大学院工学研究科, 助教 (70910678)
• Project Period (FY): 2021-07-05 – 2025-03-31
• Keywords: 精密計測 / 精密加工 / X線ミラー / X線自由電子レーザー / X線顕微鏡

Outline of Annual Research Achievements

前年度までの成果により、ほぼ予定通りにSACLAの極限集光である7nmを達成した。水平・垂直の各方向に凹面・凸面のミラーで構成される全4枚ミラーの光学系のその場アライメントは極めて有効に機能し、また、所期の計画通り、斜入射角度の許容誤差を大幅に拡大することに成功した。これにより、12時間以上のビーム特性の安定供給が可能であることも検証した。この際、ピーク強度1022W/cm2の人類が未だ経験のない硬X線強光子場を達成し、非線形光学実験への適用が可能になった。デモンストレーション実験では、Cr薄膜への9.9keVのX線集光ビーム照射を行い、蛍光X線を観察した。その結果、Cr+23において、唯一残った電子のm殻からk殻への遷移によるLyβ線を世界で初めて観測することに成功した。本実験はCr薄膜の位置を光軸方向に移動しながら、照射ビームサイズを変えることによってピーク強度をパラメータとする実験を行った。集光点での最大強度の条件では、Lyβ線の強度が低下したことから、すべての電子が放出された完全な+24価の核の生成にも成功したことも確認されている。本成果はNature Photonicsに投稿し、早々に受理され、パブリッシュされている。なお、続けて計画し、実施した3光子吸収現象の観察でも、世界初の現象の観察に成功しており、結果の解析や論文にまとめる準備を進めている。

Current Status of Research Progress

2: Research has progressed on the whole more than it was originally planned.

Reason

所期の通り、SACLAのシングルnm集光を実験に供し得るロバスト性を確保しつつ実現した。その結果、これまで実施することができなかった様々なX線非線形光学実験が可能になった。非線形光学現象の実証実験を様々に計画しており、上に示したCrからの蛍光X線の観察を行いLyβ線の観察に成功し、Nature Photonicsからパブリッシュした。

Strategy for Future Research Activity

順調に進捗しており、最終年度には、集光ミラーの多層膜のdスペースを深さ方向に2種類組み込み、2波長での高反射率を確保して、コヒーレントラマン散乱の観察に挑戦したい。ミラー反射面の多層膜構造に関する所期の計画には無い新規の研究計画であるが、可能な限りインパクトの大きい実験を実施したいと考えている。デモンストレーション実験と並行して、基礎物理の研究者との連携による強光子場物理学の最前線の探索も積極的に進めたい。

Research Products

• [Int'l Joint Research] APS (Advanced Light Source)(米国)
  • Country Name: U.S.A.
  • Counterpart Institution: APS (Advanced Light Source)
• [Journal Article] Extreme focusing of hard X-ray free-electron laser pulses enables 7 nm focus width and 10^22 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: online Pages: online
  • DOI: 10.1038/s41566-024-01411-4
  • Peer Reviewed / Open Access
• [Journal Article] High-Efficiency Polishing of Polymer Surface Using Catalyst-Referred Etching (2024)
  • Author(s): Toh Daisetsu、Takeda Kodai、Kayao Kiyoto、Ohkubo Yuji、Yamauchi Kazuto、Sano Yasuhisa
  • Journal Title: International Journal of Automation Technology Volume: 18 Pages: 240～247
  • DOI: 10.20965/ijat.2024.p0240
  • Peer Reviewed / Open Access
• [Journal Article] Role of Photoelectrochemical Oxidation in Enabling High-Efficiency Polishing of Gallium Nitride (2023)
  • Author(s): Kayao Kiyoto、Toh Daisetsu、Yamauchi Kazuto、Sano Yasuhisa
  • Journal Title: ECS Journal of Solid State Science and Technology Volume: 12 Pages: 063005～063005
  • DOI: 10.1149/2162-8777/acde61
  • Peer Reviewed / Open Access
• [Journal Article] Catalyst enhancement approach for improving the removal rate and stability of silica glass polishing via catalyzed chemical etching in pure water (2023)
  • Author(s): Toh Daisetsu、Kayao Kiyoto、Bui Pho Van、Inagaki Kouji、Morikawa Yoshitada、Yamauchi Kazuto、Sano Yasuhisa
  • Journal Title: Precision Engineering Volume: 84 Pages: 21～27
  • DOI: 10.1016/j.precisioneng.2023.07.003
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Propagation-based phase-contrast imaging method for full-field X-ray microscopy using advanced Kirkpatrick-Baez mirrors (2023)
  • Author(s): Tanaka Yuto、Yamada Jumpei、Inoue Takato、Kimura Takashi、Shimura Mari、Kohmura Yoshiki、Yabashi Makina、Ishikawa Tetsuya、Yamauchi Kazuto、Matsuyama Satoshi
  • Journal Title: Optics Express Volume: 31 Pages: 26135～26135
  • DOI: 10.1364/OE.493789
  • Peer Reviewed / Open Access
• [Journal Article] Bias-assisted photoelectrochemical planarization of GaN (0001) with impurity concentration distribution (2023)
  • Author(s): Toh D.、Kayao K.、Ohnishi R.、Osaka A. I.、Yamauchi K.、Sano Y.
  • Journal Title: AIP Advances Volume: 13 Pages: online
  • DOI: 10.1063/5.0151387
  • Peer Reviewed / Open Access
• [Journal Article] Fabrication of YAG ceramics surface without damage and grain boundary steps using catalyzed chemical wet etching (2023)
  • Author(s): Toh Daisetsu、Kayao Kiyoto、Yamauchi Kazuto、Sano Yasuhisa
  • Journal Title: CIRP Journal of Manufacturing Science and Technology Volume: 47 Pages: 1～6
  • DOI: 10.1016/j.cirpj.2023.09.001
  • Peer Reviewed / Open Access
• [Presentation] Ultra-intense hard X-ray FEL with sub-10 nm focusing (2024)
  • Author(s): J. Yamada
  • Organizer: 13th Ringberg Workshop: Science with FELs
  • Int'l Joint Research / Invited
• [Presentation] Generation of extremely intense photon field by condensation of X-ray free electron laser SACLA less than 10 nm (2023)
  • Author(s): K. Yamauchi
  • Organizer: International Conference on X-ray Optics and Applications (XOPT2023)
  • Int'l Joint Research / Invited
• [Presentation] Design, fabrication, and implementation of XFEL sub-10 nm focusing mirrors (2023)
  • Author(s): J. Yamada, T. Inoue, S. Matsuyama, N. Nakamura, Y. Tanaka, A. Ito, K. Shioi, T. Osaka, I. Inoue, Y. Inubushi, Y. Sano, M. Yabashi, and K. Yamauchi
  • Organizer: International Conference on X-ray Optics and Applications (XOPT2023)
  • Int'l Joint Research
• [Presentation] Surface finishing of a micro channel-cut crystal monochromator using high-pressure plasma etching (2023)
  • Author(s): S. Matsumura, I. Ogasahara, T. Osaka, I. Inoue, K. Yamauchi, M. Yabashi and Y, Sano
  • Organizer: International Conference on X-ray Optics and Applications (XOPT2023)
  • Int'l Joint Research
• [Presentation] Direct focus characterization of sub-10 nm XFEL using speckle patterns from random nanoparticles (2023)
  • Author(s): A. Ito, J. Yamada, Y. Tanaka, K. Shioi, S. Matsuyama, T. Inoue, I. Inoue, T. Osaka, Y. Inubushi, M. Yabashi, T. Ishikawa, and K. Yamauchi
  • Organizer: International Conference on X-ray Optics and Applications (XOPT2023)
  • Int'l Joint Research
• [Presentation] Development of distortion-free processing for narrow-gap channel-cut crystal monochromators using plasma chemical vaporization machining with a wire electrode (2023)
  • Author(s): I. Ogasahara, S. Matsumura, T. Osaka, K. Yamauchi, M. Yabashi and Y, Sano
  • Organizer: International Conference on X-ray Optics and Applications (XOPT2023)
  • Int'l Joint Research
• [Presentation] Beam diameter characterization of sub-10 nm XFEL using ptychography (2023)
  • Author(s): K. Shioi, J. Yamada, A. Ito, Y. Tanaka, S. Matsuyama, T. Inoue, T. Osaka, I. Inoue, Y. Inubushi, M. Yabashi, T. Ishikawa, and K. Yamauchi
  • Organizer: International Conference on X-ray Optics and Applications (XOPT2023)
  • Int'l Joint Research
• [Presentation] Development of phase-contrast imaging method for X-ray nanotomography with full-field X-ray microscope based on AKB mirror (2023)
  • Author(s): A. Yakushigawa, J. Yamada, Y. Tanaka, Y. Sano, H. Takano, M. Yabashi, T. Ishikawa, and K. Yamauchi
  • Organizer: International Conference on X-ray Optics and Applications (XOPT2023)
  • Int'l Joint Research
• [Presentation] High-precision finihing method for a narrow-gap channel-cut crystal X-ray monochromators using atmospheric-pressure plasma with a wire electrode (2023)
  • Author(s): S. Matsumura, I. Ogasahara, T. Osaka, K. Yamauchi, M. Yabashi and Y. Sano
  • Organizer: Optical Fabrication and Testing (OF&T)
  • Int'l Joint Research
• [Presentation] Catalyst Referred Etching Method for High Precision Optical Elements (2023)
  • Author(s): K. Yamauchi
  • Organizer: International Conference on Precision Engineering and Sustainable Manufacturing 2023(PRESM2023)
  • Int'l Joint Research / Invited
• [Presentation] Advanced Mirror-Based Optics for Hard X-Ray Focusing and Imaging Applications (2023)
  • Author(s): J. Yamada
  • Organizer: Gordon Research Conference: X-ray Scienece 2023
  • Int'l Joint Research / Invited
• [Presentation] XFEL sub-10 nm focusing with 10^22 W/cm^2 intensity: wavefront corrected mirror and focus characterization (2023)
  • Author(s): J. Yamada
  • Organizer: PhotonMEADOW2023
  • Int'l Joint Research / Invited
• [Presentation] Determination of astigmatism in XFEL sub-10 nm focusing system using speckle patterns from random nanoparticles (2023)
  • Author(s): A. Ito, J. Yamada, Y. Tanaka, K. Shioi, I. Inoue, T. Osaka, G. Yamaguchi, Y. Inubushi, M. Yabashi and K. Yamauchi
  • Organizer: PhotonMEADOW2023
  • Int'l Joint Research
• [Presentation] High-speed planarization of GaN (0001) substrate using catalyst-referred etching enhanced with positive-biased photoelectrochemical oxidation (2023)
  • Author(s): D. Toh, K. Kayao, K. Yamauchi and Y. Sano
  • Organizer: International Conference on Silicon Carbide and Related Materials (ICSCRM2023)
  • Int'l Joint Research
• [Presentation] Characteristics of Photoelectrochemical Oxidation Enabling High-efficiency Polishing of Gallium Nitride (2023)
  • Author(s): K. Kayao, D. Toh, K. Yamauchi and Y. Sano
  • Organizer: International Conference on Silicon Carbide and Related Materials (ICSCRM2023)
  • Int'l Joint Research
• [Presentation] Distortion-free Processing Method Using Plasma Chemical Vaporization Machining with a Wire Electrode for Narrow-gap Channel-cut Crystal Monochromators (2023)
  • Author(s): I. Ogasahara, S. Matsumura, K. Yamauchi and Y. Sano; T. Osaka, M. Yabashi
  • Organizer: American Society for Precision Engineering (ASPE) 2023 Annual Meeting
  • Int'l Joint Research
• [Presentation] Surface Planarization of YAG Ceramics Using Catalyst-Referred Etching (2023)
  • Author(s): Y. Yoshida, K. Kayao, D. Toh, K. Yamauchi and Y. Sano
  • Organizer: American Society for Precision Engineering (ASPE) 2023 Annual Meeting
  • Int'l Joint Research
• [Presentation] Sub-10 nm focusing of hard X-ray free-electron laser for reaching 10^22 W/cm^2 intensity (2023)
  • Author(s): J. Yamada
  • Organizer: The International Conference on Optical and Photonic Engineering (icOPEN) 2023
  • Int'l Joint Research / Invited