Implementations of quantum dynamics processors for hybrid quantum systems

• Project Area: Science of hybrid quantum systems
• Project/Area Number: 18H04286
• Research Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
• Allocation Type: Single-year Grants
• Research Institution: The University of Tokyo
• Principal Investigator: 村尾 美緒 東京大学, 大学院理学系研究科(理学部), 教授 (30322671)
• Project Period (FY): 2018-04-01 – 2020-03-31
• Project Status: Completed (Fiscal Year 2019)
• Budget Amount: ¥9,360,000 (Direct Cost: ¥7,200,000、Indirect Cost: ¥2,160,000); Fiscal Year 2019: ¥4,940,000 (Direct Cost: ¥3,800,000、Indirect Cost: ¥1,140,000); Fiscal Year 2018: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000)
• Keywords: 量子アルゴリズム / 量子動力学プロセッサ / ロバスト量子動力学制御 / 高階量子演算 / ハミルトニアン動力学制御化 / ハイブリッド量子 / 熱平衡化アルゴリズム

Outline of Annual Research Achievements

高階量子演算の枠組みを用いることで、ハミルトニアンの未知パラメータを特定することなく量子系のハミルトニアン動力学を制御・加工する「量子動力学プロセッサ」のシステムをハイブリッド量子系で実現することを目指し、昨年度に引き続き現実的な物理系に適応した「量子動力学プロセッサ」の実装方法の探索と解析を行い、次の２つの研究成果を得た。
一つは、未知のパラメータを特定することなくハミルトニアン動力学系に任意の量子ゲートを実装するロバスト動力学制御に関する研究成果である。昨年度までの研究で示した機械学習を用いた制御パルス最適化によるロバスト動力学制御アルゴリズムが現実的な状況で使えるかを解析するために、ハミルトニアンの未知パラメータが時間的に揺らぐ場合と、制御パルスの実装が不完全な場合のロバスト動力学制御への影響を数値計算によって解析した。その結果、ランダムに時間変化する連続未知パラメータを持つ場合や実装される制御パルスの振幅やパルス幅がランダムに揺らぐ場合でも、ある程度の誤差の範囲内であれば高い精度でロバスト動力学制御が可能となることが示された。
二つめの成果は、ハミルトニアン動力学系を制御ハミルトニアン動力学系に加工する量子動力学プロセッサの量子アルゴリズムについてである。我々が以前に示したハミルトニアン動力学系制御化の量子アルゴリズムでは、ハミルトニアン動力学系と同じサイズの補助メモリ空間の存在が必要であった。本研究では、補助メモリ空間を用いずにハミルトニアン動力学系の制御化を行う量子動力学プロセッサの新しい量子アルゴリズムを提案した。この量子アルゴリズムは、ユニタリゲートの基底のランダム化をさらに制御化する高階量子演算を用いることが鍵となっている。この新しい方法論の発見は、量子動力学プロセッサの今後の研究発展に役立つ方法論を与える成果である。

Research Progress Status

令和元年度が最終年度であるため、記入しない。

Strategy for Future Research Activity

令和元年度が最終年度であるため、記入しない。

Research Products

• [Int'l Joint Research] Macquarie University(オーストラリア)
• [Int'l Joint Research] Aberystwyth University(英国)
• [Int'l Joint Research] Macquarie University(オーストラリア)
• [Int'l Joint Research] KTH(スウェーデン)
• [Journal Article] Complexity of Causal Order Structure in Distributed Quantum Information Processing: More Rounds of Classical Communication Reduce Entanglement Cost (2019)
  • Author(s): Wakakuwa Eyuri、Soeda Akihito、Murao Mio
  • Journal Title: Physical Review Letters Volume: 122 Issue: 19 Pages: 190502-190502
  • DOI: 10.1103/physrevlett.122.190502
  • Peer Reviewed
• [Journal Article] Quantum State Merging for Arbitrarily Small-Dimensional Systems (2019)
  • Author(s): Hayata Yamasaki and Mio Murao
  • Journal Title: IEEE Transactions of Information Theory Volume: to be published Issue: 6 Pages: 3950-3972
  • DOI: 10.1109/tit.2018.2889829
  • Peer Reviewed
• [Journal Article] Implementing positive maps with multiple copies of an input state (2019)
  • Author(s): Dong Qingxiuxiong、Quintino Marco T?lio、Soeda Akihito、Murao Mio
  • Journal Title: Physical Review A Volume: 99 Issue: 5 Pages: 052352-052352
  • DOI: 10.1103/physreva.99.052352
  • Peer Reviewed
• [Journal Article] Complex conjugation supermap of unitary quantum maps and its universal implementation protocol (2019)
  • Author(s): Miyazaki Jisho、Soeda Akihito、Murao Mio
  • Journal Title: Physical Review Research Volume: 1 Issue: 1 Pages: 013007-013007
  • DOI: 10.1103/physrevresearch.1.013007
  • Peer Reviewed / Open Access
• [Journal Article] Robust controllability of two-qubit Hamiltonian dynamics (2019)
  • Author(s): Sakai Ryosuke、Soeda Akihito、Murao Mio、Burgarth Daniel
  • Journal Title: Physical Review A Volume: 100 Issue: 4 Pages: 042305-042305
  • DOI: 10.1103/physreva.100.042305
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Reversing Unknown Quantum Transformations: Universal Quantum Circuit for Inverting General Unitary Operations (2019)
  • Author(s): Quintino Marco T?lio、Dong Qingxiuxiong、Shimbo Atsushi、Soeda Akihito、Murao Mio
  • Journal Title: Physical Review Letters Volume: 123 Issue: 21 Pages: 210502-210502
  • DOI: 10.1103/physrevlett.123.210502
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Probabilistic exact universal quantum circuits for transforming unitary operations (2019)
  • Author(s): Quintino Marco T?lio、Dong Qingxiuxiong、Shimbo Atsushi、Soeda Akihito、Murao Mio
  • Journal Title: Physical Review A Volume: 100 Issue: 6 Pages: 062339-062339
  • DOI: 10.1103/physreva.100.062339
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Distributed Encoding and Decoding of Quantum Information over Networks (2019)
  • Author(s): Hayata Yamasaki and Mio Murao
  • Journal Title: Adv. Quantum Technol. Volume: 2 Issue: 1-2 Pages: 1800066-1800066
  • DOI: 10.1002/qute.201800066
  • Peer Reviewed
• [Presentation] Controlled quantum operations and combs, and their applications to universal controllization of divisible unitary operations (2020)
  • Author(s): Qingxiuxiong Dong, Shojun Nakayama, Akihito Soeda and Mio Murao
  • Organizer: 23rd Annual Conference on Quantum Information Processing (QIP2020)
  • Int'l Joint Research
• [Presentation] Adaptive circuits exponentially outperforms parallel ones for universal unitary inversion (2020)
  • Author(s): Marco Tulio Quintino, Qingxiuxiong Dong, Atsushi Shimbo, Akihito Soeda and Mio Murao
  • Organizer: 23rd Annual Conference on Quantum Information Processing (QIP2020)
  • Int'l Joint Research
• [Presentation] Reversing unknown quantum transformations: A universal quantum circuit for inverting general unitary operations (2020)
  • Author(s): Marco Tulio Quintino, Qingxiuxiong Dong, Atsushi Shimbo, Akihito Soeda and Mio Murao
  • Organizer: Quantum Information Structure of Spacetime HKU workshop (QISS HKU 2020)
  • Int'l Joint Research / Invited
• [Presentation] Higher order quantum operations of blackbox unitaries (2019)
  • Author(s): Mio Murao
  • Organizer: Xith International Symposium on Quantum Theory and Symmetreis (QTS2019)
  • Int'l Joint Research / Invited
• [Presentation] Using quantum computers for processing quantum systems (2019)
  • Author(s): Mio Murao
  • Organizer: Young Researchers Forum on Quantum Information Science
  • Int'l Joint Research / Invited
• [Presentation] Higher order quantum operations of blackbox unitaries (2019)
  • Author(s): Mio Murao
  • Organizer: 57th Annual Allerton Conference 2019
  • Int'l Joint Research / Invited
• [Presentation] Higher order quantum operations of blackbox unitaries (2019)
  • Author(s): Qingxiuxiong Dong, Jisho Miyazaki, Mio Murao, Shojun Nakayama, Atsushi Shimbo, Akihito Soeda, Marco Tulio Quintino
  • Organizer: International Symposium on Hybrid Quantum Systems 2019 (HQS2019)
  • Int'l Joint Research
• [Presentation] Higher order quantum operations of blackbox unitaries (2019)
  • Author(s): Mo Murao
  • Organizer: Quantum Information Processing in Non-Markovian Quantum Complex Systems (QIPQC 2019)
  • Int'l Joint Research / Invited
• [Presentation] Quantum circuit for inverting unknown unitary operations (2019)
  • Author(s): Marco Tulio Quintino, Qingxiuxiong Dong, Atsushi Shimbo, Akihito Soeda and Mio Murao
  • Organizer: 新学術領域ハイブリッド量子科学 第9回領域会議
• [Presentation] Using quantum computers for analyzing quantum physics (2018)
  • Author(s): Mio Murao
  • Organizer: International Conference on Challenges in Quantum Information Science (CQIS 2018)
  • Int'l Joint Research / Invited
• [Presentation] Using quantum computers for manipulating and analysing quantum systems (2018)
  • Author(s): Mio Murao
  • Organizer: The Bristol Quantum Information Technologies Workshop (BQIT2018)
  • Int'l Joint Research / Invited
• [Presentation] Higher order quantum operations of unitaries (2018)
  • Author(s): Mio Murao
  • Organizer: Hong Kong - Shen Zhen Workshop on Quantum Information Science
  • Int'l Joint Research / Invited
• [Presentation] Higher order quantum operations of unitaries (2018)
  • Author(s): Mio Murao
  • Organizer: 4th Seefeld workshop on Quantum Information (2018)
  • Int'l Joint Research / Invited
• [Presentation] Implementing positive maps with multiple copies of an input state (2018)
  • Author(s): Qingxiuxiong Dong, Marco Tulio Quintino, Akihito Soeda and Mio Murao
  • Organizer: 18th Asian Quantum Information Science Conference (AQIS2018)
  • Int'l Joint Research / Invited
• [Presentation] Causal structure of blackboxes in higher order quantum operations (2018)
  • Author(s): Mio Murao
  • Organizer: Quantum Maiwar 2018
  • Int'l Joint Research / Invited
• [Presentation] Inverting unknown quantum operations (2018)
  • Author(s): Qingxiuxiong Dong, Marco Tulio Quintino, Atsushi Shimbo, Akihito Soeda and Mio Murao
  • Organizer: International Conference on Challenges in Quantum Information Science (CQIS 2018)
  • Int'l Joint Research
• [Presentation] Robust control of two-qubit gates in Hamiltonian systems, (2018)
  • Author(s): Ryosuke Sakai, Akihito Soeda, Mio Murao and Daniel Burgarth
  • Organizer: International Conference on Challenges in Quantum Information Science (CQIS 2018)
  • Int'l Joint Research
• [Presentation] Entanglement cost of distributed quantum encoding/decoding (2018)
  • Author(s): Hayata Yamasaki and Mio Murao,
  • Organizer: 4th Seefeld workshop on Quantum Information
  • Int'l Joint Research
• [Presentation] Robust control of two-qubit gates in Hamiltonian systems (2018)
  • Author(s): Ryosuke Sakai, Akihito Soeda, Mio Murao and Daniel Burgarth
  • Organizer: 18th Asian Quantum Information Science Conference (AQIS2018)
  • Int'l Joint Research