The production and breakdown of the entanglement in fragment atoms following molecular dissociation

• Project/Area Number: 15K05381
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Physical chemistry
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: Kouchi Noriyuki 東京工業大学, 理学院, 教授 (50161873)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥4,940,000 (Direct Cost: ¥3,800,000、Indirect Cost: ¥1,140,000); Fiscal Year 2017: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2016: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2015: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
• Keywords: もつれ / 角度相関 / 二電子励起状態 / 角度相関関数 / Lyman-α光子

Outline of Final Research Achievements

The principal investigator of this research has theoretically shown that entangled pairs of atoms are produced through dissociation of diatomic molecules. According to the investigation, the entanglement originates from the symmetry properties that the atom-pairs possess. It is hence an interesting subject to identify electronic states of the atom-pairs and to substantiate the production of entangled pairs of fragment atoms, subject which is, according to the investigation, achieved with measuring angular correlation functions of a pair of fluorescence photons emitted by a pair of fragment atoms.
In the present research project the angular correlation function of a pair of Lyman-α photons emitted by a pair of 2p atoms is measured in photodissociation of hydrogen molecules and the electronic state of 2p atom-pairs is identified, state which turn out to be an entangled superposition between a singlet state and a triplet state.

Academic Significance and Societal Importance of the Research Achievements

もつれは、量子力学の根本であり、昨今では、量子計算の資源として盛んに研究が行なわれている。もつれた粒子系を作るためには、高度な制御技術を使用しなければならないと信じられてきた。しかしながら、本研究代表者は、二原子分子が解離すると、それが本来有している対称性のために、もつれた原子ペアが自発的に生成することを理論的に示した。本研究では、水素分子の光解離において、もつれた2p原子ペアが、自発的に生成することを、Lyman-α光子ペアの角度相関測定により実証した。

Research Products

• [Int'l Joint Research] University of Kassel(ドイツ)
• [Int'l Joint Research] University of Kassel(Germany)
• [Int'l Joint Research] University of Oulu(Finland)
• [Int'l Joint Research] University of Kassel(Germany)
• [Int'l Joint Research] University of Kassel(Germany)
• [Journal Article] Breaking space-inversion symmetry in the dynamics of the doubly excited Q21Πu(1) state of HD (2019)
  • Author(s): Hosaka Kouichi、Torizuka Yutaro、Schmidt Philipp、Knie Andre、Ehresmann Arno、Odagiri Takeshi、Kitajima Masashi、Kouchi Noriyuki
  • Journal Title: Physical Review A Volume: 99 Issue: 3 Pages: 033423-033423
  • DOI: 10.1103/physreva.99.033423
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] The observation of the pair of Lyman-α and Lyman-β photons produced in the photodissociation of H2 (2017)
  • Author(s): K. Hosaka, Y. Torizuka, P. Schmidt, T. Odagiri, A. Knie, K. Jankala, A. Ehresmann, M. Kitajima and N. Kouchi
  • Journal Title: Journal of Physics: Conference Series Volume: Volume 875 Pages: 032002-032002
  • DOI: 10.1088/1742-6596/875/4/032002
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Dynamics of the Q21Πu(1) state studied from the isotope effect on the cross sections for the formation of the 2p atom pair in the photoexcitation of H2 and D2 (2016)
  • Author(s): Kouichi Hosaka, Kennichi Shiino, Yuko Nakanishi, Takeshi Odagiri, Masashi Kitajima, and Noriyuki Kouchi
  • Journal Title: Physical Review A Volume: Volume 93, Issue 6 Issue: 6
  • DOI: 10.1103/physreva.93.063423
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Angular correlation measurements of a pair of Lyman-α photons emitted in the photodissociation of H2 (2015)
  • Author(s): K. Hosaka, Y. Nakanishi, R. Kogo, P. Schmidt, Y. Torizuka, K. Shigemura, T. Odagiri, A. Knie, K. Jankala, A. Ehresmann, M. Nakano, Y. Kumagai, K. Shiino, M. Kitajima and N. Kouchi
  • Journal Title: Journal of Physics: Conference Series Volume: Volume 635 Issue: 11 Pages: 112016-112016
  • DOI: 10.1088/1742-6596/635/11/112016
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] HD 分子 2 電子励起状態の崩壊過程 (2019)
  • Author(s): 穂坂綱一, 鳥塚祐太郎, Philipp Schmidt, Andre Knie, Arno Ehresmann, 小田切丈, 北島昌史, 河内宣之
  • Organizer: 量子ビームサイエンスフェスタ, 第36回PFシンポジウム
• [Presentation] 分子解離でもつれ原子ペアが生まれるか？ (2018)
  • Author(s): 鳥塚祐太郎，穂坂綱一，Philipp Schmidt，小田切丈，Andre Knie，Kari Jänkälä，Arno Ehresmann，向後陵子，北島昌史，河内宣之
  • Organizer: 原子衝突学会第43回年会
• [Presentation] 分子の解離で、もつれ原子ペアが作れるか？ (2018)
  • Author(s): 河内宣之
  • Organizer: 「弱値・弱測定、エンタングルメント、量子コヒーレンスの新地平」研究会
  • Invited
• [Presentation] 水素(H2, D2, HD)の光解離により生成する2p原子ペアのもつれと前駆2電子励起状態の対称性 (2017)
  • Author(s): 鳥塚祐太郎, 穂坂綱一, Schmidt Philipp, 谷内一史, 小田切丈, Knie Andre，Jänkälä Kari, Ehresmann Arno, 向後陵子, 北島昌史, 河内宣之
  • Organizer: 日本物理学会, 第72回年次大会
  • Place of Presentation: 大阪大学豊中キャンパス
  • Year and Date: 2017-03-17
• [Presentation] H2の光解離で生成する2p-3p原子ペアの観測 (2017)
  • Author(s): 穂坂綱一, 鳥塚祐太郎, Philipp Schmidt, 小田切丈, Andre Knie, Kari Jankala, Arno Ehresmann, 北島昌史, 河内宣之
  • Organizer: 量子ビームサイエンスフェスタ, 第34回PFシンポジウム
  • Place of Presentation: つくば国際会議場
  • Year and Date: 2017-03-14
• [Presentation] 水素の光解離で生成するLyman-α光子ペアの角度相関 -分子の対称性と解離原子ペアのもつれ- (2017)
  • Author(s): 河内宣之
  • Organizer: 第30回日本放射光学会年会・放射光科学合同シンポジウム
  • Place of Presentation: 神戸芸術センター
  • Year and Date: 2017-01-07
  • Invited
• [Presentation] Are entangled pairs of fragment atoms produced in the photodissociation of H2? (2017)
  • Author(s): Noriyuki Kouchi
  • Organizer: Workshop on Fundamental Aspects of Quantum Mechanics as They Relate to Atomic, Molecular and Optical (AMO) Physics
  • Int'l Joint Research / Invited
• [Presentation] 水素(H2, HD, D2)の光解離で生成するLyman-α光子ペアの角度相関 (2016)
  • Author(s): 鳥塚祐太郎, 穂坂綱一, Schmidt Philipp, 谷内一史, 小田切丈, Knie Andre，Jänkälä Kari, Ehresmann Arno, 北島昌史, 河内宣之
  • Organizer: 第10回分子科学討論会2016
  • Place of Presentation: 神戸ファッションマート
  • Year and Date: 2016-09-13
• [Presentation] 2電子励起水素分子のダイナミクス-H2, HD, 及び D2からの2p原子ペア生成断面積の比較 (2016)
  • Author(s): 穂坂綱一, 鳥塚祐太郎, Schmidt Philipp, 谷内一史, 小田切丈, Knie Andre，Jänkälä Kari, Ehresmann Arno, 北島昌史, 河内宣之
  • Organizer: 第10回分子科学討論会2016
  • Place of Presentation: 神戸ファッションマート
  • Year and Date: 2016-09-13
• [Presentation] Unexpected isotope effect on the cross section of 2p pair formation in the photoexcitation of H2, D2 and HD (2016)
  • Author(s): HOSAKA, Kouichi; TORIZUKA, Yutaro; YACHI, Kazufumi; SCHMIDT, Philipp; KNIE, Andre; JANKALA, Kari; EHRESMANN, Arno; ODAGIRI, Takeshi; KITAJIMA, Masashi; KOUCHI, Noriyuki
  • Organizer: The 32nd Syposium on Chemical Kinetics and Dynamics
  • Place of Presentation: 大宮ソニックシティ
  • Year and Date: 2016-06-01
  • Int'l Joint Research
• [Presentation] 2電子励起水素分子のダイナミクス 2p原子ペア生成断面積に現れる同位体効果 (2016)
  • Author(s): 穂坂綱一, 鳥塚祐太郎, 谷内一史, Philipp Schmidt, Andre Knie, Kari Jankala, Arno Ehresmann, 小田切丈, 北島昌史, 河内宣之
  • Organizer: 日本物理学会, 第71回年会
  • Place of Presentation: 東北学院大学泉キャンパス(宮城県)
  • Year and Date: 2016-03-19
• [Presentation] 水素分子(H2, HD, 及びD2)の光解離による2p原子ペア生成断面積 (2016)
  • Author(s): 穂坂綱一, 鳥塚祐太郎, 谷内一史, Philipp Schmidt, Andre Knie, Kari Jankala, Arno Ehresmann, 小田切丈, 北島昌史, 河内宣之
  • Organizer: 量子ビームサイエンスフェスタ, 第33回PFシンポジウム
  • Place of Presentation: つくば国際会議場(茨城県)
  • Year and Date: 2016-03-15
• [Presentation] H2およびHD分子の光解離で生成するLyman-α光子ペアの角度相関 (2015)
  • Author(s): 鳥塚祐太郎, 穂坂綱一, 谷内一史, Philipp Schmidt, 小田切丈, Andre Knie，Kari Jankala, Arno Ehresmann, 北島昌史, 河内宣之
  • Organizer: 第9回分子科学討論会
  • Place of Presentation: 東京工業大学大岡山キャンパス(東京都)
  • Year and Date: 2015-09-16
• [Presentation] Angular correlation measurements of a pair of Lyman-α photons emitted in the photodissociation of H2 (2015)
  • Author(s): K. Hosaka, Y. Nakanishi, R. Kogo, P. Schmidt, Y. Torizuka, K. Shigemura, T. Odagiri, A. Knie, K. Jankala, A. Ehresmann, M. Nakano, Y. Kumagai, K. Shiino, M. Kitajima and N. Kouchi
  • Organizer: The 29th International Conference on Photonic, Electronic, and Atomic Collisions
  • Place of Presentation: Toledo, Spain
  • Year and Date: 2015-07-22
  • Int'l Joint Research