Keitaro KUWAHARAProfessor
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Paper
- Local noncentrosymmetric effect on antiferromagnetic ordering in the tetragonal crystal structure phase of Eu3Ir4Sn13
Takanobu Kumada; Yotaro Suzuki; Kazuaki Iwasa; Keitaro Kuwahara; Hajime Sagayama; Hironori Nakao; Motoyuki Ishikado; Akinori Hoshikawa, American Physical Society (APS)
Physical Review B, 31 Mar. 2025, [Reviewed] - Neutron scattering study on dimerized 4f1 intermetallic compound Ce5Si3
Daichi Ueta; Yuki Iwata; Riki Kobayashi; Keitaro Kuwahara; Takatsugu Masuda; Shinichi Itoh
Physical Review B, 09 May 2024, [Reviewed] - Antiferromagnetic ordering and chiral crystal structure transformation in Nd3Rh4Sn13
Ami Shimoda; Kazuaki Iwasa; Keitaro Kuwahara; Hajime Sagayama; Hironori Nakao; Motoyuki Ishikado; Akiko Nakao; Seiko Ohira-Kawamura; Naoki Murai; Takashi Ohhara; Yusuke Nambu
Physical Review B, 16 Apr. 2024, [Reviewed] - Magnetic Ordering and Structural Phase Transitions of Nd3T4Sn13 (T = Rh and Ir)
Ami Shimoda; Kazuaki Iwasa; Keitaro Kuwahara; Hajime Sagayama; Hironori Nakao; Motoyuki Ishikado; Takashi Ohhara; Akiko Nakao; Akinori Hoshikawa; and Toru Ishigaki
JPS Conference Proceedings, 23 May 2023, [Reviewed] - Gaps in topological magnon spectra: Intrinsic versus extrinsic effects
Seung-Hwan Do; Joseph A. M. Paddison; Gabriele Sala; Travis J. Williams; Koji Kaneko; Keitaro Kuwahara; Andrew F. May; Jiaqiang Yan; Michael A. McGuire; Matthew B. Stone; Mark D. Lumsden; and Andrew D. Christianson
PHYSICAL REVIEW B, 24 Aug. 2022, [Reviewed] - Magnetic Excitations in Chiral-Structure Phase of Ce3Ir4Sn13
Kazuaki Iwasa; Seiya Nakazato; Daisuke Hashimoto; Mami Shiozawa; Keitaro Kuwahara; Hajime Sagayama; Seiko Ohira-Kawamura; Naoki Murai; Devashibhai T. Adroja; and André M. Strydom
Journal of the Physical Society of Japan, 02 Nov. 2021, [Reviewed] - Helical and Collinear Spin-Density-Wave Orders in S = 1/2 One-dimensional Frustrated Chain Compound NaCuMoO4(OH) Investigated by Neutron Scattering
Shinichiro Asai; Takuma Oyama; Kazuhiro Nawa; Akiko Nakao; Koji Munakata; Keitaro Kuwahara; Masato Hagihala; Shinichi Itoh; Zenji Hiroi; and Takatsugu Masuda
Physical Review B, 28 Apr. 2020, [Reviewed] - Single-Crystal Growth and Physical Properties of EuZn2Ge2
Masashi Kosaka; Shinji Michimura; Hikaru Hirabayashi; Ryosuke Numakura; Ryosuke Iizuka; Keitaro Kuwahara; Yoshiya Uwatoko
Journal of the Physical Society of Japan, 08 Apr. 2020, [Reviewed] - Successive Phase Transitions in R3Ir4Sn13 (R: La and Ce) Investigated Using Neutron and X-ray Diffraction
Seiya Nakazato; Kazuaki Iwasa; Daisuke Hashimoto; Mami Shiozawa; Keitaro Kuwahara; Hironori Nakao; Hajime Sagayama; Motoyuki Ishikado; Takashi Ohhara; Akiko Nakao; Koji Munakata; and Ryoji Kiyanagi
JPS Conf. Proc., 19 Mar. 2020, [Reviewed] - URu2Si2 under intense magnetic fields: From hidden order to spin-density wave
W. Knafo; D. Aoki; G.W. Scheerer; F. Duc; F. Bourdarot; K. Kuwahara; H. Nojiri; L.-P. Regnault; J.Flouquet, Elsevier B.V.
Physica B, 01 May 2018, [Reviewed] - Structure of the magnetic excitations in the spin-1/2 triangular-lattice Heisenberg antiferromagnet Ba3CoSb2O9
S. Ito; N. Kurita; H. Tanaka; S. Ohira-Kawamura; K. Nakajima; S. Itoh; K. Kuwahara; K. Kakurai
Nature Communications, 10 Aug. 2017, [Reviewed] - First report on the Electronic, Magnetic and thermal Properties of Filled Skutterudite YbOs4Sb12
H. Kunitoshi; T. D. Matsuda; R. Midorikawa; R. Higashinaka; K. Kuwahara; Y. Aoki; H. Sato
Journal of the Physical Society of Japan, 2016, [Reviewed] - Field-induced spin-density wave beyond hidden order in URu2Si2
W. Knafo; F. Duc; F. Bourdarot; K. Kuwahara; H. Nojiri; D. Aoki; J. Billette; P. Frings; X. Tonon; E. Lelièvre-Berna; J. Flouquet; and L.-P. Regnault
Nature Communications, 2016, [Reviewed] - Intermultiplet transitions in filled skutterudite SmFe4P12
S. Konno; A. Suzuki; K. Nihei; K. Kuwahara; D. Kawana; T. Yokoo and S. Itoh
Journal of Physics: Conference Series, 2015 - Science from the Initial Operation of HRC
S. Itoh; T. Yokoo; T. Masuda; H. Yoshizawa; M. Soda; Y. Ikeda; S. Ibuka; D. Kawana; T. J. Sato; Y. Nambu; K. Kuwahara; S. Yano; J. Akimitsu; Y. Kaneko; Y. Tokura; M. Fujita; M. Hase; K. Iwasa; H. Hiraka; T. Fukuda; K. Ikeuchi; K. Yoshida; T. Yamaguchi; K. Ono; and Y. Endoh
JPS Conference Proceedings, 2015 - Electronic State of CeFe4As12 Investigated by Using Single Crystals Grown under High Pressure of 4 GPa
Y. Ogawa; H. Sato; M. Watanabe; T. Namiki; S. Tatsuoka; R. Higashinaka; Y. Aoki; K. Kuwahara; J. Yamaura; and Z. Hiroi
Journal of the Physical Society of Japan, 21 Feb. 2014 - Magnetic Structure of Phase II in U(Ru0.96Rh0.04)(2)Si-2 Determined by Neutron Diffraction under Pulsed High Magnetic Fields
K. Kuwahara; S. Yoshii; H. Nojiri; D. Aoki; W. Knafo; F. Duc; X. Fabreges; G. W. Scheerer; P. Frings; G. L. J. A. Rikken; F. Bourdarot; L. P. Regnault; J. Flouquet
PHYSICAL REVIEW LETTERS, May 2013 - Magnetic Excitation in Totally Symmetric Staggered Ordered Phase of PrFe4P12
K. Iwasa; L. Hao; M. Kohgi; K. Kuwahara; J.-M. Mignot; H. Sugawara; Y. Aoki; T.D. Matsuda; and H. Sato
Journal of the Physical Society of Japan, 2012 - Neutron scattering study on magnetic ordering in a partially rare-earth filled skutterudite PrxFe4Sb12
K. Iwasa; T. Orihara; K. Saito; K. Tomiyasu; Y. Murakami; H. Sugawara; K. Kuwahara; H. Kimura; R. Kiyanagi; Y. Ishikawa; Y. Noda; Y. Aoki; H. Sato and M. Kohgi
Journal of Physics: Conference Series, 2012 - Renormalized Motion of Dysprosium Atoms Filling Boron Cages of DyB6
K. Iwasa; K. Kuwahara; Y. Utsumi; K. Saito; H. Kobayashi; T. Sato; M. Amano; T. Hasegawa; N. Ogita; M. Udagawa; S. Tsutsui; and A.Q.R. Baron
Journal of the Physical Society of Japan, 2012 - Strong Effect of Yb Filling Fraction on the Magnetic Ground Sate of the Filled Skutterudite YbFe4Sb12
T. Saito; H. Sato; K. Tanaka; S. Tatsuoka; M. Ueda; R. Higashinaka; T. Namiki; Y. Aoki; Y. Utsumi; K. Kuwahara; and T. Hosoya
Journal of the Physical Society of Japan, 2011 - Motion of the guest ion as precursor to the first-order phase transition in the cage system GdB6
K. Iwasa; R. Igarashi; K. Saito; C. Laulhé; T. Orihara; S. Kunii; K. Kuwahara; H. Nakao; Y. Murakami; F. Iga; M. Sera; S. Tsutsui; H. Uchiyama; and A.Q.R. Baron
Physical Review B, 2011 - Pressure-Induced Antiferromagnetic Order in Filled Skutterudite PrFe4P12 Studied by Single-Crystal High-Pressure Neutron Diffraction
T. Osakabe; K. Kuwahara; D. Kawana; K. Iwasa; D. Kikuchi; Y. Aoki; M. Kohgi and H. Sato
Journal of the Physical Society of Japan, 2010 - Response of Itinerant-Electron Weak Ferromagnet LaFe4As12 to Pressure and Magnetic Field
S. Tatsuoka; M. Watanabe; B. Suemitsu; Y. Ogawa; A. Yamada; K. Matsubayashi; Y. Uwatoko; R. Higashinaka; Y. Aoki; T. Namiki; K. Kuwahara; and H. Sato
Journal of the Physical Society of Japan, 2010 - Current understanding of the heavy fermion superconductivity in PrOs4Sb12
H. Sato; K. Tanaka; D. Kikuchi; T. Namiki; R. Higashinaka; Y. Aoki; M. Kohgi; H. Sugawara; K. Kuwahara; and K. Iwasa
Physica C, 2010 - Excitation spectrum of PrOs4Sb12 under a magnetic field
S. Raymond; K. Kuwahara; K. Kaneko; K. Iwasa; M. Kohgi; A. Hiess; J. Flouquet; N. Metoki; H. Sugawara; Y. Aoki and H. Sato
Journal of Physics: Condensed Matter, 2009, [Reviewed] - Crystal Field Effect on Superconducting Transition in PrxOs4Sb12
K.Tanaka; T. Namiki; A.Imamura; M. Ueda; T. Saito; S. Tatsuoka; R. Miyazaki; K. Kuwahara; Y. Aoki; and H. Sato
Journal of the Physical Society of Japan, 2009 - Magnetic octupole order in Ce0.7La0.3B6: A polarized neutron diffraction study
K. Kuwahara; K. Iwasa; M. Kohgi; N. Aso; M. Sera; F. Iga; M. Matsuura; and K. Hirota
Physica B, 2009 - Crystal field excitations in PrFe4Sb12 synthesized under high pressure
K. Kuwahara; K. Tanaka; T. Saito; S. Tatsuoka; K. Iwasa; M. Watanabe; Y. Aoki; H. Sato; M. Kohgi; K. Iwasa; H. Sugawara; C. Stock and D. T. Adroja
Journal of Physics: Conference Series, 2009 - Anomalous Electronic Behaviors in Ferromagnetic Kondo Lattice SmFe4P12
D. Kikuchi; H. Sugawara; K. Tanaka; H. Aoki; M. Kobayashi; S. Sanada; K. Kuwahara; Y. Aoki; H. Shishido; R. Settai; Y. Ōnuki; H. Harima; and H. Sato
Journal of the Physical Society of Japan, 2008 - Magnetic Excitations in Heavy Electron State of Filled Skutterudite PrxLa1-xFe4P12 (x = 1.00 and 0.85)
K. Iwasa; L. Hao; T. Hasegawa; K. Horiuchi; Y. Murakami; J. Otsuki; Y. Kuramoto; M. Kohgi; K. Kuwahara; H. Sugawara; Y. Aoki; and H. Sato
Journal of the Physical Society of Japan, 2008 - Itinerant-Electron Weak Ferromagnetism in La-Based Filled Skutterudite LaFe4As12
S. Tatsuoka; H. Sato; K. Tanaka; M. Ueda; D. Kikuchi; H. Aoki; T. Ikeno; K. Kuwahara; Y. Aoki; H. Sugawara; and H. Harima
Journal of the Physical Society of Japan, 2008 - Crystal Field Excitations in the Filled Skutterudite NdOs4Sb12
K. Kuwahara; M. Takagi; K. Iwasa; S. Itobe; D. Kikuchi; Y. Aoki; M. Kohgi; H. Sato and H. Sugawara
Physica B, 2008 - Neutron scattering study on the field-induced O-xy-type antiferroquadrupolar ordering of the heavy-fermion superconductor PrOs4Sb12
K. Kaneko; N. Metoki; R. Shiina; T. D. Matsuda; M. Kohgi; K. Kuwahara; N. Bernhoeft
PHYSICAL REVIEW B, Mar. 2007 - Detection of Neutron Scattering from Phase IV of Ce0.7La0.3B6: A Confirmation of the Octupole Order
K. Kuwahara; K. Iwasa; M. Kohgi; N. Aso; M.i Sera and F. Iga
Journal of the Physical Society of Japan, 2007, [Reviewed] - Nonmagnetic Ground State in Fully Filled PrxFe4Sb12 (x=1.0) Synthesized under High Pressure
K. Tanaka; Y. Kawahito; Y. Yonezawa; D. Kikuchi; H. Aoki; K. Kuwahara; M. Ichihara; H. Sugawara; Y. Aoki; and H. Sato
Journal of the Physical Society of Japan, 2007 - Inelastic neutron scattering measurements in a quadrupolar ordering compound YbSb
A. Oyamada; K. Kuwahara; K. Ohoyama; K. Iwasa; M. Kohgi and S. Maegawa
Journal of Magnetism and Magnetic Materials, 2007 - Elastic anomalies of UGe2
K. Kuwahara; T. Sakai; M. Kohgi; Y. Haga and Y. Onuki
Journal of Magnetism and Magnetic Materials, 2007 - Structural Transformation on the Pressure-Induced Metal Insulator Transition in PrFe4P12
D. Kawana; K. Kuwahara; M. Sato; M. Takagi; Y. Aoki; M. Kohgi; H. Sato; H. Sagayama; T. Osakabe; K. Iwasa and H. Sugawara
Journal of the Physical Society of Japan, 2006, [Reviewed] - Unusual Electronic State of the Low-Carrier System CeSb under High Pressure Studied by Simultaneous Measurement of Electrical Resistivity and Lattice Parameter
A. Hannan; Y. Okayama; T. Osakabe; K. Kuwahara and M. Kohgi
Journal of the Physical Society of Japan, 2006 - The Unconventional Superconductivity of Skutterudite PrOs4Sb12: Time-Reversal Symmetry Breaking and Adjacent Field-Induced Quadrupole Ordering
Y. Aoki; T. Tayama; T. Sakakibara; K. Kuwahara; K. Iwasa; M. Kohgi; W. Higemoto; D.E. MacLaughlin; H. Sugawara and H. Sato
Journal of the Physical Society of Japan, 2006 - Study of Phonon Anomalies of Rare Earth Hexaborides RB6
M. Kohgi; K. Kuwahara; N. Ogita; M. Udagawa and F. Iga
Journal of the Physical Society of Japan, 2006 - Magnetic and Transport Properties of Gd3Ir4Sn13 with Unique Crystal Structure
C. Nagoshi; R. Yamamoto; K. Kuwahara; H. Sagayama; D. Kawana; M. Kohgi; H. Sugawara; Y. Aoki; H. Sato; T. Yokoo and M. Arai
Journal of the Physical Society of Japan, 2006 - Magnetic form factor of URu2Si2
K. Kuwahara; M. Kohgi; K. Iwasa; M. Nishi; K. Nakajima; M. Yokoyama and H. Amitsuka
Physica B, 2006 - Direct Observation of Quadrupolar Excitons in the Heavy-Fermion Superconductor PrOs4Sb12
K. Kuwahara; K. Iwasa; M. Kohgi; K. Kaneko; N. Metoki; S. Raymond; M.-A. Measson; J. Flouquet; H. Sugawara; Y. Aoki and H. Sato
Physical Review Letters, 2005 - Evolution of 4f-Electron States in the Metal-Insulator Transition of PrRu4P12
K. Iwasa; L. Hao; K. Kuwahara; M. Kohgi; S.R. Saha; H. Sugawara; Y. Aoki; H. Sato; T. Tayama and T. Sakakibara
Physical Review B, 2005 - Powder neutron diffraction studies of structure and magnetic Ce ordering in the strongly correlated electron compound Ce0.75La0.2511B6
P. Fischer; K. Iwasa; K. Kuwahara; M. Kohgi; T. Hansen and S. Kunii
Physical Review B, 2005 - Study of High-field Magnetic Phases of the low-carrier-system CeP by Synchrotron Radiation X-ray Diffraction
A. Hanan; D. Kawana; K. Kuwahara; M. Kohgi; Y. Narumi; Y. Tabata; S. Shimomura; Y. Tanaka and K. Katsumata
Journal of the Physical Society of Japan, 2005 - Role of p-f Hybridization in the Metal-Non-Metal Transition of PrRu4P12
K. Iwasa; L. Hao; T. Hasegawa; T. Takagi; K. Horiuchi; Y. Mori; Y. Murakami; K. Kuwahara; M. Kohgi; H. Sugawara; S.R. Saha; Y. Aoki and H. Sato
Journal of the Physical Society of Japan, 2005 - Resonant and non-resonant x-ray scattering from GdB6
K. Kuwahara; R. Yamamoto; M. Kohgi; H. Nakao; K. Ishii; K. Iwasa; Y. Murakami; S. Kunii; H. Sagayama; Y. Wakabayashi and H. Sawa
Physica B, 2005 - Magnetic Excitations in the Heavy-Fermion Superconductor PrOs4Sb12
K Kuwahara; K Iwasa; M Kohgi; K Kaneko; S Araki; N Metoki; H Sugawara; Y Aoki; H Sato
Journal of the Physical Society of Japan, 2004, [Reviewed] - Neutron-diffraction studies of the unusual ordered phases of Ce0.75La0.25B6
K. Iwasa; K. Kuwahara; M. Kohgi; P. Fischer; A. Donni; L. Keller; T. C. Hansen; S. Kunii; N. Metoki and K. Ohyama
Physica B, 2003, [Reviewed] - EXCED - Epithermal neutron diffractometer at KENS
K. Kuwahara; S. Sugiyama; K. Iwasa; M. Kohgi; M. Nakamura; Y. Inamura; M. Arai and S. Kunii
Applied Physics A, 2002 - Magnetic form factor of UGe2 under high pressure
K. Kuwahara; H. Sagayama; K. Iwasa; M. Kohgi; Y. Haga; Y. Onuki; K. Kakurai; M. Nishi; K. Nakajima; N. Aso and Y. Uwatoko
Physica B, 2002 - Spatially inhomogeneous development of antiferromagnetism in URu2Si2: Evidence from 29Si NMR under pressure
K. Mastuda; Y. Kohori; T. Kohara; K. Kuwahara and H. Amitsuka
Physical Review Letters, 2001, [Reviewed] - Effect of pressure on tiny antiferromagnetic moment in the heavy-electron compound URu(2)Si(2)
H Amitsuka; M Sato; N Metoki; M Yokoyama; K Kuwahara; T Sakakibara; H Morimoto; S Kawarazaki; Y Miyako; JA Mydosh
PHYSICAL REVIEW LETTERS, Dec. 1999, [Reviewed] - Lattice instability and elastic responce in the heavy electron system URu2Si2
K. Kuwahara; H. Amitsuka; T. Sakakibara; O. Suzuki; S. Nakamura; T. Goto; M. Mihalik; A.A. Menovsky; A. de Visser and J.J.M. Franse
Journal of the Physical Society of Japan, 1997, [Reviewed]
