Publications

査読付き or 投稿中

1. “Plastic tensor networks for interpretable generative modeling”
   Katsuya O. Akamatsu, Kenji Harada, Tsuyoshi Okubo, Naoki Kawashima
   arXiv:2504.06722
2. “TeNeS-v2: Enhancement for Real-Time and Finite Temperature Simulations of Quantum Many-Body Systems”
   Yuichi Motoyama, Tsuyoshi Okubo, Kazuyoshi Yoshimi, Satoshi Morita, Tatsumi Aoyama, Takeo Kato, Naoki Kawashima
   arXiv:2501.07777
3. “Efficient tomography of microwave photonic cluster states”
   Yoshiki Sunada, Shingo Kono, Jesper Ilves, Takanori Sugiyama, Yasunari Suzuki, Tsuyoshi Okubo, Shuhei Tamate, Yutaka Tabuchi, and Yasunobu Nakamura
   arXiv:2410.03345
4. “Tensor tree learns hidden relational structures in data to construct generative models”
   Kenji Harada, Tsuyoshi Okubo, and Naoki Kawashima
   Machine Learning: Science and Technology, 6 025002 (2025)(arXiv:2408.10669)
5. “Nuclear norm regularized loop optimization for tensor network”
   Kenji Homma, Tsuyoshi Okubo, and Naoki Kawashima
   Physical Review Research 6, 043102 (2024)(arXiv:2306.17479)
6. “Quantum phase transition between spin liquid and spin nematics in spin-1 Kitaev honeycomb model”
   Tohru Mashiko and Tsuyoshi Okubo
   Physical Review Research 6, 033110 (2024)(arXiv:2403.11490)
7. “Quantum spin state stabilized by coupling with classical spins”
   H. Yamaguchi, T. Okubo, A. Matsuo, T. Kawakami, Y. Iwasaki, T. Takahashi, Y. Hosokoshi, and K. Kindo
   Physical Review B 109, L100404 (2024). (arXiv:2404.06767)
8. “Spin Seebeck Effect as a Probe for Majorana Fermions in Kitaev Spin Liquids”
   Yasuyuki Kato, Joji Nasu, Masahiro Sato, Tsuyoshi Okubo, Takahiro Misawa, and Yukitoshi Motome
   Physical Review X 15, 011050 (2025)(arXiv:2401.13175)
9. "Absorbing Phase Transitions in Artificial Deep Neural Networks"
   Keiichi Tamai, Tsuyoshi Okubo, Truong Vinh Truong Duy, Naotake Natori, and Synge Todo,
   arXiv:2307.02284
10. “Hunting for quantum-classical crossover in condensed matter problems”
    Nobuyuki Yoshioka, Tsuyoshi Okubo, Yasunari Suzuki, Yuki Koizumi, and Wataru Mizukami,
    npj Quantum Information 10, Article number: 45 (2024).(arXiv:2210.14109)
11. “Possibility of a topological phase transition in two-dimensional RP³ model”
    Tsuyoshi Okubo and Naoki Kawashima,
    Journal of Physical Society of Japan, 92, 114701 (2010) (arXiv:2112.15053)
12. "TeNeS: Tensor Network Solver for Quantum Lattice Systems”
    Yuichi Motoyama, Tsuyoshi Okubo, Kazuyoshi Yoshimi, Satoshi Morita, Takeo Kato, and Naoki Kawashima,
    Comput. Phys. Commun. 279, 108437 (2022) (arXiv:2112.13184)
13. “Gapped ground state in a spin-1/2 frustrated square lattice”
    H. Yamaguchi, N. Uemoto, T. Okubo, Y. Kono, S. Kittaka, T. Sakakibara, T. Yajima, S. Shimono, Y. Iwasaki, and Y. Hosokoshi,
    Physical Review B 104, L060411 (2021). (arXiv:2108.12761)
14. “Quantum critical phenomena in a spin-1/2 frustrated square lattice with spatial anisotropy”
    H. Yamaguchi, Y. Iwasaki, Y. Kono, T. Okubo, S. Miyamoto, Y. Hosokoshi, A. Matsuo, T. Sakakibara, T. Kida, and M. Hagiwara,
    Physical Review B 103, L220407 (2021). (arXiv:2106.12126)
15. “Optimized Implementation for Calculation and Fast-Update of Pfaffians Installed to the Open-Source Fermionic Variational Solver mVMC”
    RuQing G. Xu, Tsuyoshi Okubo, Synge Todo, and Masatoshi Imada,
    Comput. Phys. Commun. 277, 108375 (2022). (arXiv:2105.13098)
16. “Bond-weighted Tensor Renormalization Group”
    Daiki Adachi, Tsuyoshi Okubo, and Synge Todo,
    Physical Review B 105, L060402 (2022). (arXiv:2011.01679)
17. “Zero-energy excitation in the classical kagome antiferromagnet NaBa₂Mn₃F₁₁“
    Shohei Hayashida, Hajime Ishikawa, Yoshihiko Okamoto, Tsuyoshi Okubo, Zenji Hiroi, Gøran J. Nilsen, Hannu Mutka, and Takatsugu Masuda,
    Physical Review B 101, 214409 (2020). (arXiv:2006.01526).
18. "Phase Shift in Skyrmion Crystals”
    Satoru Hayami, Tsuyoshi Okubo, and Yukitoshi Motome,
    Nature Communications 12, 6927 (2021). (arXiv:2005.03168).
19. "Magnetic-field Induced Quantum Phases in Tensor Network Study of Kitaev Magnets"
    Hyun-Yong Lee, Ryui Kaneko, Li Ern Chern, Tsuyoshi Okubo, Youhei Yamaji, Naoki Kawashima, and Yong Baek Kim,
    Nature Communications 11, 1639 (2020). (arXiv:1908.07671).
20. "Abelian and Non-Abelian Chiral Spin Liquids in a Compact Tensor Network Representation"
    Hyun-Yong Lee, Ryui Kaneko, Tsuyoshi Okubo, Naoki Kawashima,
    Physical Review B 101, 035140 (2020). (arXiv:1907.02268).
21. “Anisotropic Tensor Renormalization Group”
    D. Adachi, T. Okubo and S. Todo,
    Physical Review B 102, 054432 (2020). (arXiv:1906.02007)
22. "A series of magnon crystals appearing under ultrahigh magnetic fields in a kagomé antiferromagnet"
    R. Okuma, D. Nakamura, T. Okubo, A. Miyake, A. Matsuo, K. Kindo, M. Tokunaga, N. Kawashima, S. Takeyama and Z. Hiroi,
    Nature Communications vol 10, Article number: 1229 (2019).
23. "Multiple-q states of the J₁-J₂ classical honeycomb-lattice Heisenberg antiferromagnet under magnetic fields"
    Tokuro Shimokawa, Tsuyoshi Okubo, Hikaru Kawamura,
    Physical Review B 100, 224404 (2019). (arXiv:1902.01582).
24. "Gapless Kitaev Spin Liquid to Classical String Gas through Tensor Networks"
    Hyun-Yong Lee, Ryui Kaneko, Tsuyoshi Okubo, Naoki Kawashima,
    Physical Review Letters 123, 087203 (2019).  (arXiv:1901.05786).
25. "Field-enhanced quantum fluctuation in an $S=\frac{\mathrm{1/}}{2}$ frustrated square lattice"
    H. Yamaguchi, Y. Sasaki, T. Okubo, M. Yoshida, T. Kida, M. Hagiwara, Y. Kono, S. Kittaka, T. Sakakibara, M. Takigawa, Y. Iwasaki, and Y. Hosokoshi,
    Physical Review B 98, 094402 (2018). (arXiv:1808.06812)
26. "Magnetic State Selected by Magnetic Dipole Interaction in Kagome Antiferromagnet NaBa₂Mn₃F₁₁"
    Shohei Hayashida, Hajime Ishikawa, Yoshihiko Okamoto, Tsuyoshi Okubo, Zenji Hiroi, Maxim Avdeev, Pascal Manuel, Masato Hagihala, Minoru Soda, Takatsugu Masuda,
    Physical Review B 97, 054411 (2018). (arXiv:1712.06740)
27. "Quantum phase transitions driven by rhombic-type single-ion anisotropy in the S=1 Haldane chain",
    Yu-Chin Tzeng, Hiroaki Onishi, Tsuyoshi Okubo, and Ying-Jer Kao,
    Physical Review B 96, 060404(R) (2017). (arXiv:1705.01558)
28. "Weak ferromagnetic order breaking the threefold rotational symmetry of the underlying kagome lattice in CdCu₃(OH)₆(NO₃)₂⋅H₂O",
    R. Okuma, T. Yajima, D. Hamane, T. Okubo, and Z. Hiroi,
    Physical Review B 95, 095427 (2017). （arXiv:1703.09357）
29. "Ground state properties of Na₂IrO₃ determined from ab initio Hamiltonian and its extensions containing Kitaev and extended Heisenberg interactions",
    T. Okubo, K. Shinjo, Y. Yamaji, N. Kawashima, S. Sota, T. Tohyama, and M. Imada,
    Physical Review B 96, 054434 (2017). (arXiv:1611.03614)
30. "Experimental Realization of a Quantum Pentagonal Lattice",
    H. Yamaguchi, T. Okubo, S. Kittaka, T. Sakakibara, K. Araki, K. Iwase, N. Amaya, T. Ono, and Y. Hosokoshi,
    Scientific Reports5, 15327 (2015).
31. "SU(N) Heisenberg model with multi-column representations",
    T. Okubo, K. Harada, J. Lou, and N. Kawashima,
    Physical Review B 92, 134404 (2015). （arXiv:1504.05332）
32. "Scaling relation for dangerously irrelevant symmetry-breaking fields",
    T. Okubo, K. Oshikawa, H. Watanabe, and N. Kawashima,
    Physical Review B 91, 174417 (2015). （arXiv:1411.1872）
33. "Field-induced incommensurate phase in the strong-rung spin ladder with ferromagnetic legs",
    H. Yamaguchi, H. Miyata, M. Yoshida, M. Takigawa, K. Iwase, T. Ono, N. Kase, K. Araki, S. Kittaka, T. Sakakibara, T. Shimokawa, T. Okubo, K. Okunishi, A. Matsuo, and Y. Hosokoshi,
    Physical Review B 89, 220402 (2014). （arXiv:1406.2231）
34. "Snapshot spectrum and critical phenomenon for two-dimensional classical spin systems",
    Y. Imura, T. Okubo, S. Morita, and K. Okunishi,
    Journal of Physical Society of Japan, 83, 114002 (2014) . (arXiv:1402.6767）
35. "Kagome-Triangular Lattice Antiferromagnet NaBa₂Mn₃F₁₁",
    H. Ishikawa, T. Okubo, Y. Okamoto, and Z. Hiroi,
    Journal of Physical Society of Japan, 83, 043703 (2014). （arXiv:1403.2128）
36. "Various regimes of quantum behavior in an S=1/2 Heisenberg antiferromagnetic chain with fourfold periodicity",
    H. Yamaguchi, T. Okubo, K. Iwase, T. Ono, Y. Kono, S. Kittaka, T. Sakakibara, A. Matsuo, K. Kindo, Y. Hosokoshia,
    Physical Review B 88, 174410 (2013). （arXiv:1311.4763）
37. "Possibility of Deconfined Criticality in SU(N) Heisenberg Models at Small N",
    K. Harada, T. Suzuki, T. Okubo H. Matsuo, J. Lou, H. Watanabe, S. Todo, and N. Kawashima,
    Physical Review B 88, 220408(R) (2013). （arXiv:1307.0501）
38. "Finite-temperature transition of the distorted kagome-lattice Heisenberg antiferromagnet",
    H. Masuda, T.Okubo and H. Kawamura,
    Physical Review Letters 109, 057201 (2012). (arXiv:1201.5441)
39. "Multiple-q states and the skyrmion lattice of the triangular lattice Heisenberg antiferromag in magnetic fields ",
    T.Okubo, S. Chung and H. Kawamura,
    Physical Review Letters 108, 017206 (2012). ( arXiv:1109.6161)
40. "Cubic and non-cubic multiple-q states in the Heisenberg antiferromagnet on the pyrochlore lattice",
    Tsuyoshi Okubo, Trung Hai Nguyen and Hikaru Kawamura,
    Physical Review B 84, 144432 (2011). (arXiv:1107.5440)
41. "Novel spin-liquid states in the frustrated Heisenberg antiferromagnet on the honeycomb lattice",
    S. Okumura, H. Kawamura, T. Okubo and Y. Motome,
    Journal of Physical Society of Japan, 79, 114705 (2010) . ( arXiv:1004.4441)
42. "Signature of a Z₂vortex in the dynamical correlations of the triangular-lattice Heisenberg antiferromagnet" ,
    T. Okubo and H. Kawamura ,
    Journal of Physical Society of Japan, 79, 084706 (2010) (arXiv:1004.4730 )
43. "Phase transition of the three-dimensional chiral GL model
    --- search fo the chiral phase" ,
    T. Okubo and H. Kawamura,
    Physical Review B 82, 014404 (2010).
    (arXiv:1001.4662).
44. "Z₂-Vortex Ordering of the Triangular-Lattice Heisenberg Antiferromagnet",
    H. Kawamura, A. Yamamoto and T. Okubo,
    Journal of the Physical Society of Japan 79, 023701 (2010) (arXiv:0909.0121).
45. "Mean-field analysis of phase transitions in the emergence of hierarchical society",
    T. Okubo and T. Odagaki,
    Physical Review E 76, 036105 (2007).
46. "Dissipative process under a boundary perturbation",
    T. Okubo and T. Odagaki,
    Physical Review E 73, 026128 (2006).
47. "Random packing of binary hard discs"
    T. Okubo and T. Odagaki
    Journal of Physics : Condensed Matter 16, 6651 (2004).

プロシーディングス（査読付き）

1. “Embedding of Tree Tensor Networks into Shallow Quantum Circuits”
   Shota Sugawara, Kazuki Inomata, Tsuyoshi Okubo, Synge Todo,
   In Proceedings of the 17th International Conference on Agents and Artificial Intelligence – Volume 1: QAIO; ISBN 978-989-758-737-5; ISSN 2184-433X, SciTePress, pages 793-803.
   (arXiv:2501.18856)
2. “Tensor Network-Based Lightweight Energy Forecasting for Virtual Power Plant”
   D. Watari, H. Tanimoto, T. Okubo, S. Todo, and K. Nishiyama,
   Proceedings of ICRERA2024, 469 (2024).

プロシーディングス（査読なし）

1. 深層学習モデル軽量化のためのテンソルトレイン分解による計算量削減手法
   谷本寛樹、篠崎佑太、新浩治、西山薫、大久保毅、藤堂眞治
   第31回画像センシングシンポジウム SSII2025, IS3-18 (2025).
2. テンソルトレインにおける重みの初期化方法の提案
   谷本寛樹、渡大地、篠崎佑太、西山薫、大久保毅、藤堂眞治
   ビジョン技術の実利用ワークショップ（ViEW）2024, IS2-6 (2024).
3. テンソルネットワークを用いた電力需要予測モデルの軽量化に関する研究
   渡　大地, 谷本寛樹, 大久保毅, 藤堂眞治, 西山　薫,
   2024年 情報科学技術フォーラム(FIT), F-038 (2024).
4. 信号伝搬過程におけるスケーリング則に基づく人工深層ニューラルネットワークの系統的な設計
   玉井敬一, 大久保毅, ヴィン チュオン ズイ チュオン, 名取 直毅, 藤堂 眞治
   人工知能学会全国大会論文集, 3Q4-OS-17a-03, (2024).
5. 人工深層ニューラルネットワークが示す吸収状態転移
   玉井敬一, 大久保毅, ヴィン チュオン ズイ チュオン, 名取 直毅, 藤堂 眞治
   人工知能学会全国大会論文集, 2Q6-OS-20b-02, (2023).
6. Packing and Percolation of poly-disperse discs and spheres
   Takashi Odagaki, Tsuyoshi Okubo, Ryusei Ogata, and Keiji Okazaki,
   The Proceedings of Second COE Workshop on Sphere Packings, Kyushu University, pp. 187-197, (2005).
   （arXiv:cond-mat/0508633)

依頼された文章

1. 「物性物理における「量子加速」の探索」
   吉岡信行, 大久保毅, 鈴木泰成, 水上渉、応用物理 93 巻 3 号 p. 165-168, 2024.
2. 「拡張キタエフ模型における熱ホール伝導度のテンソルネットワーク法による研究」
   大久保毅、固体物理 Vol. 57, No.11, 633-642, 2022.
3. 「量子多体系とテンソルネットワーク」
   大久保毅、数理科学2022年12月号, 58-64, 2022.
4. 「テンソルネットワークの将来」
   大久保毅、数理科学2022年2月号, 65-72, 2022.
5. 「テンソルネットワークによる情報圧縮とフラストレート磁性体への応用」
   大久保毅、第63回物性若手夏の学校テキスト、物性研究 Vol. 7, No.2 (2018).
6. 「テンソルネットワーク形式の進展と応用」
   西野友年、大久保毅、日本物理学会誌 Vol 72, No. 10, 2017
7. "Massively parallel Monte Carlo simulation of a possible topological phase transition in two-dimensional frustrated spin systems"
   Tsuyoshi Okubo, Invited paper in ISSP Supercomputer Activity Report 2016.
8. 「第８回日本物理学会若手奨励賞を受賞して」
   大久保毅　物性研だより 第54巻第2号 2014年7月 （PDFが物性研のwebサイトにあります）
9. 「フラストレート磁性体における多重Q秩序とスカーミオン格子状態」
   大久保毅、川村光　日本物理学会誌 Vol. 67, No. 7, 2012
10. "Multiple-q states and skyrmion lattice in frustrated triangular-lattice Heisenberg antiferromagnet"
    Tsuyoshi Okubo and Hikaru Kawamura, Invited paper in ISSP Supercomputer Activity Report 2012.

学位論文

• 卒業論文：「ニ成分剛体円盤のランダムパッキング」　大久保毅２００３年３月
• 修士論文：「量子力学に従う粒子の初到達時間と境界摂動に対する応答」　大久保毅２００５年３月
• 博士論文："Linear Response under a Boundary Perturbation"　Tsuyoshi Okubo ２００8年３月