Spectrum control of laser-produced plasma light sources applying the band emission characteristic of multiply charged high-Z ions

• Project/Area Number: 15K17728
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Atomic/Molecular/Quantum electronics
• Research Institution: University of Toyama
• Principal Investigator: OHASHI Hayato 富山大学, 教養教育院(五福), 講師 (60596659)
• Research Collaborator: HIGASHIGUCHI Takeshi 宇都宮大学, 工学研究科, 教授 (80336289) ; SAKAUE Hiroyuki 核融合科学研究所, ヘリカル研究部, 助教 (40250112)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥4,030,000 (Direct Cost: ¥3,100,000、Indirect Cost: ¥930,000); Fiscal Year 2017: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2016: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2015: ¥2,600,000 (Direct Cost: ¥2,000,000、Indirect Cost: ¥600,000)
• Keywords: 多価イオン / レーザー生成プラズマ / 光源 / 軟X線～極端紫外 / 電子ビームイオントラップ / 軟X線－極端紫外

Outline of Final Research Achievements

In this study, we measured emission spectra of multiply charged high-Z ions using an ion source named an electron beam ion trap, which can control the maximum charge state of ions in the source by controlling the electron beam energy, and also the Large Helical Device to acquire useful unknown atomic data such as a transition wavelength in the soft x-ray region to extreme ultraviolet for the analysis of plasma emission. Target elements were bismuth, lead, gold, rhenium, zirconium, germanium and gallium.
The emission pattern of laser-produced plasma, which is a light source candidate in the soft x-ray to extreme ultraviolet region, changes in various ways depending on the irradiation conditions. We demonstrated the possibility of spectral control by using dual laser pulses to find more optimum conditions.

Academic Significance and Societal Importance of the Research Achievements

本研究では複数の重元素について多くの未知の原子データやプラズマの最適発光条件を取得することに成功した。本成果はプラズマの解析に大きく貢献できるものであり，光源としての実用化に寄与するものである。また，同元素を工業利用する際にも基礎原子データとして役立つものである。一方，レーザー生成プラズマの発光スペクトル制御がダブルパルス法により可能なことが示され，調整可能なパラメーターが増えたことで，光源としてより効率的なプラズマ発光の最適条件を見出すことが可能となった。

Research Products

• [Int'l Joint Research] University College Dublin(アイルランド)
• [Int'l Joint Research] Lanzhou University(中国)
• [Journal Article] Spectral dynamics of soft x-ray emission in dual laser-produced medium-Z plasma (2018)
  • Author(s): H. Ohashi, H. Hara, G. Arai, T. Hatano, T. Ejima, C. Suzuki, S. Namba, A. Sasaki, M. Nishikino, G. O'Sullivan, T. Higashiguchi
  • Journal Title: Applied Physics B Volume: 124 Issue: 10 Pages: 193-193
  • DOI: 10.1007/s00340-018-7061-3
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Emission of water-window soft x-rays under optically thin conditions using low-density foam targets (2018)
  • Author(s): H. Hara, H. Kawasaki, T. Tamura, T. Hatano, T. Ejima, W. Jiang, H. Ohashi, S. Namba, A. Sunahara, A. Sasaki, M. Nishikino, G. O'Sullivan, T. Higashiguchi
  • Journal Title: Optics Letters Volume: 43 Issue: 15 Pages: 3750-3753
  • DOI: 10.1364/ol.43.003750
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Intense water-window soft x-ray emission by spectral control using dual laser pulses (2018)
  • Author(s): G. Arai, H. Hara, T. Hatano, T. Ejima, W. Jiang, H. Ohashi, S. Namba, A. Sunahara, A. Sasaki, M. Nishikino, G. O'Sullivan, T. Higashiguchi
  • Journal Title: Optics Express Volume: 26 Issue: 21 Pages: 27748-27756
  • DOI: 10.1364/oe.26.027748
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] Characteristics of water-window soft X-ray emission from bismuth plasmas (2018)
  • Author(s): H. Ohashi, H. Hara, B. Li, P. Dunne, G O'Sullivan, A. Sasaki, C. Suzuki, N. Tamura, H. A. Sakaue, D. Kato, I. Murakami and T. Higashiguchi
  • Organizer: 2nd Asia-Pacific Conference on Plasma Physics (AAPPS-DPP2018) Ishikawa Prefectural Bunkyo Hall, Kanazawa, Japan, November 12nd-17th, 2018.
  • Int'l Joint Research / Invited
• [Presentation] EBITを用いた多価Biイオンの軟X線分光 (2017)
  • Author(s): 石見良太，大橋隼人，坂上裕之
  • Organizer: 原子衝突学会第42回年会
• [Presentation] Emission spectroscopy of laser-produced and electron beam ion trap plasmas with high-Z elements in extreme ultraviolet and soft x-ray region (2016)
  • Author(s): H. Ohashi, H. Hara, G. Arai, Y. Kondo, T.-H. Dinh, B. Li, P. Dunne, G. O'Sullivan, N. Nakamura, H. A. Sakaue, D. Kato, I. Murakami and T. Higashiguchi
  • Organizer: 10th International Conference on Atomic and Molecular Data and Their Applications (ICAMDATA2016)
  • Place of Presentation: GunsanSaemangeum Convention Center (GSCO), Gunsan, Republic of Korea
  • Year and Date: 2016-09-25
  • Int'l Joint Research / Invited