Element-specific observation of ultrafast dynamics in light-induced photocatalysis using X-ray free-electron lasers

• Project/Area Number: 25790093
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Quantum beam science
• Research Institution: Japan Synchrotron Radiation Research Institute
• Principal Investigator: KATAYAMA Tetsuo 公益財団法人高輝度光科学研究センター, XFEL利用研究推進室, 研究員 (90648073)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Project Status: Completed (Fiscal Year 2014)
• Budget Amount: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000); Fiscal Year 2014: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000); Fiscal Year 2013: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
• Keywords: X線自由電子レーザー / 超高速時間分解計測 / X線吸収分光 / 時間分解X線吸収分光

Outline of Final Research Achievements

I have developed two experimental schemes, dispersive and fluorescence yield methods, for time resolved x-ray absorption spectroscopy. To confirm their performance to trace the ultrafast intermediates in light-induced reactions, time-resolved measurements were performed for iron ferrioxalate solution, combined with synchronized optical laser. I successfully observed the bond dissociation, change of electronic structures with sub-picosecond time resolution.
Furthermore, I have tried to improve the time resolution limited by the relative timing jitter between XFEL and optical laser. The high-intensity x-ray irradiation induces the fast increase of electronic temperature and transmission decrease inside the semiconductor (GaAs) wafer. Combined with spatial decoding, the timing jitter was measured. I successfully achieved ~10 femtoseconds accuracy in the measurement, which improves the time resolution drastically.

Research Products

• [Journal Article] Femtosecond time-resolved X-ray absorption spectroscopy of liquid using a hard X-ray free electron laser in a dual-beam dispersive detection method (2014)
  • Author(s): Yuki Obara, Tetsuo Katayama, Yoshihiro Ogi, Takayuki Suzuki, Naoya Kurahashi, Shutaro Karashima, Yohei Chiba,Yusuke Isokawa,Tadashi Togashi, Yuichi Inubushi, Makina Yabashi, Toshinori Suzuki, and Kazuhiro Misawa
  • Journal Title: Optics Express Volume: 22 Issue: 1 Pages: 1105-1113
  • DOI: 10.1364/oe.22.001105
  • NAID: 120005366003
  • Peer Reviewed
• [Journal Article] Femtosecond x-ray absorption spectroscopy with hard x-ray free electron laser (2013)
  • Author(s): Tetsuo Katayama, Yuichi Inubushi, Yuki Obara, Takahiro Sato, Tadashi Togashi, Kensuke Tono, Takaki Hatsui, Takashi Kameshima, Atanu Bhattacharya, Yoshihiro Ogi, Naoya Kurahashi, Kazuhiko Misawa, Toshinori Suzuki, and Makina Yabashi
  • Journal Title: Applied Physics Letters Volume: 103 Issue: 13
  • DOI: 10.1063/1.4821108
  • Peer Reviewed
• [Presentation] Ultrafast X-ray Absorption Spectroscopy Using Femto-second X-ray Pulses (2015)
  • Author(s): Tetsuo Katayama
  • Organizer: 岡崎コンファレンス
  • Place of Presentation: 愛知県岡崎市
  • Year and Date: 2015-02-03 – 2015-02-05
  • Invited
• [Presentation] XFELを用いた超高速フェムト秒XAFS測定 (2014)
  • Author(s): Tetsuo Katayama
  • Organizer: 日本分析化学会
  • Place of Presentation: 広島県広島市
  • Year and Date: 2014-09-17 – 2014-09-19
  • Invited
• [Presentation] 透過型回折格子を用いたXFEL吸収分光法の開発 (2014)
  • Author(s): 片山 哲夫、犬伏 雄一、小原 祐樹、佐藤 尭洋、富樫 格、 登野 健介、初井 宇記、亀島 敬、Atanu Bhattacharya、小城 吉寛、 倉橋 直也、三沢 和彦、鈴木 俊法、矢橋 牧名
  • Organizer: 日本放射光学会
  • Place of Presentation: 広島
• [Presentation] Ultrafast dynamics studies at XFEL SACLA (2014)
  • Author(s): Tetsuo Katayama
  • Organizer: The 2nd XFEL Workshop on Dynamics
  • Place of Presentation: Pohang, Korea
  • Invited
• [Presentation] Instruments and Applications of SACLA Beamline (2014)
  • Author(s): Tetsuo Katayama
  • Organizer: Euro-XFEL user meeting
  • Place of Presentation: Hamburg, Germany
• [Remarks] 世界で初めて、X線自由電子レーザーを用いたフェムト秒領域でのX線直接吸収分光測定に成功
  • URL: http://www.spring8.or.jp/ja/news_publications/press_release/2014/140110/
• [Remarks] X線自由電子レーザーパルスの特性を生かした高効率X線吸収分光法の開発
  • URL: http://www.spring8.or.jp/ja/news_publications/press_release/2013/130924/
• [Remarks] 世界で初めて、X線自由電子レーザーを用いたフェムト秒領域でのX線直接吸収分光測定に成功
  • URL: http://www.spring8.or.jp/ja/news_publications/press_release/2014/140110/
• [Remarks] X線自由電子レーザーパルスの特性を生かした高効率X線吸収分光法の開発
  • URL: http://www.spring8.or.jp/ja/news_publications/press_release/2013/130924/