Selected Papers

"Dynamics of quantum spin-nematics: Comparisons with canted antiferromagnets",
T. Momoi, Phys. Rev. Research 6, 013169 (2024). [arXiv]
"Magnetically Hidden State on the Ground Floor of the Magnetic Devil’s Staircase",
S. Imajo, N. Matsuyama, T. Nomura, T. Kihara, S. Nakamura, C. Marcenat, T. Klein, G. Seyfarth, C. Zhong, H. Kageyama, K. Kindo, T. Momoi, and Y. Kohama, Phys. Rev. Lett. 129, 147201 (2022). [arXiv]
"Effects of Dzyaloshinskii-Moriya Interactions in Volborthite: Magnetic Orders and Thermal Hall Effect",
Shunsuke Furukawa and T. Momoi, J. Phys. Soc. Jpn. 89, 034711 (2020). [arXiv]
"Spin nematics in frustrated spin-dimer systems with bilayer structure",
Toshiya Hikihara, Takahiro Misawa, and T. Momoi, Phys. Rev. B 100, 214414 (2019). [arXiv]
"Kinetic frustration induced supersolid in the S=1/2 kagome lattice antiferromagnet in a magnetic field",
Xavier Plat, T. Momoi, Chisa Hotta, Phys. Rev. B 98, 014415 (2018). [arXiv]
"Electron spin resonance for the detection of long-range spin nematic order",
Shunsuke C. Furuya and T. Momoi, Phys. Rev. B 97, 104411 (2018). [arXiv]
Magnetic behavior of volborthite Cu3V2O7(OH)2(H2O)2 determined by coupled trimers rather than frustrated chains,
O. Janson, S. Furukawa, T. Momoi, P. Sindzingre, J. Richter, and K. Held, Phys. Rev. Lett. 117, 037206 (2016). [arXiv]
Novel phases in a square-lattice frustrated ferromagnet : 1/3-magnetisation plateau, helicoidal spin-liquid and vortex crystal,
L. Seabra, P. Sindzingre, T. Momoi, and N. Shannon, Phys. Rev. B 93, 085132 (2016). [arXiv]
Z3 symmetry-protected topological phases in the SU(3) AKLT model,
T. Morimoto, H. Ueda, T. Momoi, and A. Furusaki, Phys. Rev. B 90, 235111 (2014). [arXiv]
Dynamical spin structure factors of quantum spin nematic states,
R. Shindou, S. Yunoki, and T. Momoi, Phys. Rev. B 87, 054429 (2013). [arXiv]
Spin-nematic and spin-density-wave orders in spatially anisotropic frustrated magnets in a magnetic field,
M. Sato, T. Hikihara, and T. Momoi, Phys. Rev. Lett. 110, 077206 (2013). [arXiv]
Spin nematic order in multiple-spin exchange models on the triangular lattice,
T. Momoi, P. Sindzingre, and K. Kubo, Phys. Rev. Lett. 108, 057206 (2012). [arXiv]
Phase diagram of the classical Heisenberg antiferromagnet on a triangular lattice in an applied magnetic field,
L. Seabra, T. Momoi, P. Sindzingre, and N. Shannon, Phys. Rev. B 84, 214418 (2011). [arXiv]
Projective studies of spin nematics in a quantum frustrated ferromagnet,
R. Shindou, S. Yunoki, and T. Momoi, Phys. Rev. B 84, 134414 (2011). [arXiv]
Magnetic phase diagram of the spin-1/2 antiferromagnetic zigzag ladder,
T. Hikihara, T. Momoi, A. Furusaki, and H. Kawamura, Phys. Rev. B 81, 224433 (2010). [arXiv]
SU(2) slave-boson formulation of spin nematic states in S=1/2 frustrated ferromagnets,
R. Shindou and T. Momoi, Phys. Rev. B 80, 064410 (2009). [arXiv]
NMR relaxation rate and dynamical structure factors in nematic and multipolar liquids of frustrated spin chains under magnetic fields,
M. Sato, T. Momoi, and A. Furusaki, Phys. Rev. B 79, 060406(R) (2009). [arXiv]
Vector chiral and multipolar orders in the spin-1/2 frustrated ferromagnetic chain in magnetic field,
T. Hikihara, L. Kecke, T. Momoi, and A. Furusaki, Phys. Rev. B 78, 144404 (2008). [arXiv]
Finite temperature Mott transition in Hubbard model on anisotropic triangular lattice,
T. Ohashi, T. Momoi, H. Tsunetsugu, and N. Kawakami, Phys. Rev. Lett. 100 (2008) 076402. [arXiv]
Multimagnon bound states in the frustrated ferromagnetic one-dimensional chain,
L. Kecke, T. Momoi, and A. Furusaki, Phys. Rev. B 76 (2007) 060407(R). [arXiv]
Octupolar Order in the Multiple Spin Exchange Model on a Triangular Lattice,
T. Momoi, Philippe Sindzingre, Nic Shannon, Phys. Rev. Lett. 97 (2006) 257204. [arXiv]
Nematic Order in Square Lattice Frustrated Ferromagnets,
Nic Shannon, T. Momoi, Philippe Sindzingre, Phys. Rev. Lett. 96 (2006) 027213. [arXiv]
Nuclear Magnetic Orderings and Frustration in Bcc 3He in High Magnetic Fields,
Hiroshi Fukuyama, K. Yawata, T. Momoi, H. Ikegami, H. Ishimoto, [arXiv]
Duality Relations and Exotic Orders in Electronic Hubbard Ladders,
T. Momoi and T. Hikihara, J. Phys. Soc. Jpn. Suppl. 74 (2005) 226-233. [arXiv]
Exact Duality Relations in Interacting Electron Systems,
T. Momoi and T. Hikihara, Phys. Rev. Lett. 91 (2003) 256405. [arXiv]
Effect of Zero Point Motion on Solidification of Quantum Particles,
D. S. Hirashima, T. Momoi, and Takagi, J. Phys. Soc. Jpn. 72 (2003) 1446.
Scalar Chiral Ground States of Spin Ladders with Four-Spin Exchanges,
T. Momoi, T. Hikihara, M. Nakamura, and X. Hu, Phys. Rev. B 67 (2003) 174410. [arXiv]
Spin-Chirality Duality in a Spin Ladder with Four-Spin Cyclic Exchange,
T. Hikihara, T. Momoi, and X. Hu, Phys. Rev. Lett. 90 (2003) 087204. [arXiv]
Quantum Melting of Incommensurate Domain Walls in Two Dimensions,
T. Momoi, Phys. Rev. B 67 (2003) 014529. [arXiv]
Ferromagnetism in the One-Dimensional Hubbard Model with Orbital Degeneracy: From Low to High Electron Density ,
H. Sakamoto, T. Momoi, and Kenn Kubo, Phys. Rev. B 65 (2002) 224403. [arXiv]
Magnetization Plateaus of the Shastry-Sutherland model for SrCu2(BO3)2: SDW, supersolid, and bound states ,
T. Momoi and K. Totsuka, Phys. Rev. B. 62 (2000) 15067-15078. [arXiv]
Magnetic Order in the Double Exchange Model in Infinite Dimensions ,
K. Nagai, T. Momoi, and K. Kubo, J. Phys. Soc. Jpn. 69 (2000) 1837-1844. [arXiv]
Magnetization Plateaus as Insulator-Superfluid Transitions in Quantum Spin Systems ,
T. Momoi and K. Totsuka, Phys. Rev. B 61 (2000) 3231-3234. [arXiv]
Magnetization Plateau in a Two-Dimensional Multiple-Spin Exchange Model ,
T. Momoi, H. Sakamoto, and K. Kubo, Phys. Rev. B 59 (1999) 9491-9499. [arXiv]
Ferromagnetism in the Hubbard Model with Orbital Degeneracy in Infinite Dimensions ,
T. Momoi and K. Kubo, Phys. Rev. B 58 (1998) R567-R570. [arXiv]
Possible Chiral Phase Transition in Two-Dimensional Solid 3He ,
T. Momoi, K. Kubo, and Koji Niki, Phys. Rev. Lett. 79 (1997) 2081-2084. [arXiv]
Ground State of a Spin System with Two- and Four-Spin Exchange Interactions on the Triangular Lattice ,
K. Kubo and T. Momoi, Z. Phys. B. 103 (1997) 485-489. [arXiv]
On the Bloch Theorem Concerning Spontaneous Electric Current ,
Y. Ohashi and T. Momoi, J. Phys. Soc. Jpn. 65 (1996) 3254-3259. [arXiv]
Quantum Fluctuations in Quantum Lattice Systems with Continuous Symmetry ,
T. Momoi, J. Stat. Phys. 85 (1996) 193-210. [arXiv]
Energy Spectra of the Nambu-Goldstone modes in the Hubbard Model ,
T. Momoi, Phys. Lett. A 201 (1995) 261-267. [Abstract]
Spectral Properties and Sum Rules of the One-Dimensional Hubbard Model ,
T. Momoi, Phys. Lett. A. 195 (1994) 351-357. [Abstract]
An Upper Bound for the Spin-Wave Spectrum of the Heisenberg Antiferromagnet ,
T. Momoi, J. Phys. Soc. Jpn. 63 (1994) 2507-2510. [arXiv]
Low-Lying Excited States of Quantum Antiferromagnets on a Triangular Lattice ,
T. Momoi, J. Stat. Phys. 75 (1994) 707-734. [arXiv]
Ground-State Properties and Phase Diagram of the Quantum XXZ Antiferromagnet on a Triangular Lattice,
T. Momoi and M. Suzuki, J. Phys. Soc. Jpn. 61 (1992) 3732-3744. [PDF file]

Review Articles

"Detecting Fingerprints of Bimagnon Formation in Frustrated Ferromagnetic Chains",
Tsutomu Momoi, JPSJ News and Comments 12, 09 (2015).
多体交換相互作用が創る固体ヘリウム3薄膜の磁性 (Magnetism of solid helium-3 thin films induced by multiple-spin exchange),
桃井　勉、久保　健 (T. Momoi and K. Kubo), 固体物理 (Solid State Physics) Vol. 47, No. 5 (2012) 207-216. [PDF]
磁性体中のスピンの量子ネマティック状態 (Spin Nematic States in Frustrated Magnets),
桃井　勉 (T. Momoi), 日本物理学会誌 (BUTSURI) Vol. 65, No. 5 (2010) 345-348. [PDF]
Magnetism and Electronic States of Systems with Strong Hund Coupling ,
K. Kubo, D. M. Edwards, A. C. M. Green, T. Momoi, and H. Sakamoto, "Physics of Manganites", eds. by T.A. Kaplan and S.D. Mahanti, (Plenum Publishers, 1999), p.71-86. [arXiv]

Doctor Thesis

Ground States and Elementary Excitations of Quantum Antiferromagnets ,
Tsutomu Momoi (University of Tokyo, March 1995) [PDF (no figure)]

Invited Talks

"Physics of Spin nematics",
T. Momoi, Tutorial lecture in 74th Annual Meeting of Physical Society of Japan, (Kyushu Univ., March 2019).
"Supersolid in the kagome antiferromagnet in a magnetic field",
T. Momoi, The 2nd Asia Pacific Workshop on Quantum Magnetism (ICTS Bangalore, India, Dec 02, 2018).
"スピンネマティク相の出現とマグノン対励起"、 桃井　勉、強磁場フォーラム主催研究会「強磁場コラボラトリーが拓く未踏計測領域への挑戦と物質・材料科学の最先端」（物質・材料研究機構、2017年11月30日）.
"Spin nematics in frustrated magnets and their electron-spin resonance",
T. Momoi, Junjiro Kanamori Memorial International Symposium - New Horizon of Magnetism - (University of Tokyo, Sept 28, 2017).
"正方格子フラストレート強磁性体における1/3磁化プラトー、ヘリコイダルスピン液体、ボーテックス結晶"、 桃井　勉、東大物性研短期研究会「スピン系物理の深化と最前線」（東京大学物性研究所、2015年11月17日）.
"磁性体中のネマティック状態"、 桃井　勉、早稲田大学高等研究所 Top Runners' Lecture Collection of Science 「磁性体研究の最前線: フラストレーションと強磁場が生む量子現象」（早稲田大学、2015年4月30日）。
"Theory of field induced spin nematic phase in frustrated magnets",
T. Momoi, Symposium in 70th Annual Meeting of Physical Society of Japan, (Waseda Univ., March 2015).
"フラストレート磁性体におけるネマティック状態"、 桃井　勉、ワークショップ「統計力学の最近の展開」（東京大学小柴ホール、2014年3月3日）。
"フラストレート磁性体における量子スピンネマティック状態"、 桃井　勉、京大基研研究会「量子スピン系の物理」（京都大学、2012年11月）。
"Spin nematics in spin-1/2 frustrated magnets" ,
T. Momoi, The International Conference on Frustrated Spin Systems, Cold Atoms, Nanomaterials, (Hanoi, July 14-16, 2010).
"Nematic spin liquid in frustrated magnets" ,
T. Momoi, UK-Japan meeting on Novel Quantum Phases in Oxide Materials, (Bristol, 22 February 2010).
"Nematic and multipolar orders in spin-1/2 frustrated magnets" ,
T. Momoi, International Symposium on Topological Aspects of Solid State Physics, (Yukawa Institute, Kyoto, June 2008).
"Magnetic multipole orders in frustrated ferromagnets" ,
T. Momoi, ISSP International Workshop and Symposium on Computational Approaches to Quantum Critical Phenomena, (Kashiwa, August 2006).
"Symposium on novel quantum phases realized in super clean materials; Nobel quantum magnetism induced by ring exchanges" ,
T. Momoi, 60th Annual Meeting of Physical Society of Japan, (Tokyo Univ. of Science, March 2005).
"Duality relations and exotic orders on ladder systems" ,
T. Momoi, Yukawa International Seminar 2004 (YKIS 2004), (Kyoto, November 2004).
"Duality and Exotic Order in Correlated Electron Ladder Systems" ,
T. Momoi, International Conference on Statistical Physics of Quantum Systems -novel orders and dynamics-, (Sendai, July 2004).
"Scalar chiral order in the two-leg spin ladder with four-spin exchanges" ,
T. Momoi, 2nd Workshop on Orbital Ordering and Fluctuations in d- and f-electron Systems, (Tokai, Feb 2003).
"Magnetization plateaus of two dimensional frustrated antiferromagnets" ,
T. Momoi, 1st Washington Conference on Electronic Structure of Complex Materials (ESCM2000), (Washington DC, July 2000).
"Symposium on magnetism of the two-dimensional spin gap system SrCu2(BO3)2: "Theory" ,
K. Totsuka and T. Momoi, 55th Annual Meeting of Physical Society of Japan, (Kansei Univ., March 2000).
"Magnetic Phases in a Spin System with Multiple Spin Exchanges",
K. Kubo and T. Momoi, 22nd Low Temperature Physics Conference (LT), (Helsinki, August 1999).
"Magnetism and Electronic States of Systems with Strong Hund Coupling" ,
K. Kubo, D.M. Edwards, A.C.M. Green, T. Momoi, and H. Sakamoto, Workshop "Physics of Manganites", (Michigan, July, 1998).
"Magnetism of Two-Dimensional Solid 3He; Chiral Symmetry Breaking in a Spin System with Four-Spin Exchange Interactions" ,
T. Momoi, 53rd Annual Meeting of Physical Society of Japan, (Tohou Univ., March 1998).