Performance information

• Ultrasonic Investigation of the Eu-based Intermetallic System EuZn2Ge2
  Shinya Kudo; Kazuki Saito; Takuto Sato; Mitsuteru Nakamura; Masahito Yoshizawa; Kazuhei Wakiya; Yoshiki Nakanishi; Hikaru Hirabayashi; Shinji Michimura; Masashi Kosaka
  New Physics: Sae Mulli, Volume：73, Number：12, First page：1046, Last page：1049, Dec. 2023, [Reviewed]
  Korean Physical Society, Scientific journal
  DOI：https://doi.org/10.3938/npsm.73.1046
  DOI ID：10.3938/npsm.73.1046, ISSN：0374-4914, eISSN：2289-0041
• Magnetic ground state of YbCo₂Zn₂₀ probed by muon spin relaxation
  Wataru Higemoto; Kazuhiko Satoh; Takashi U Ito; Kazuki Ohishi; Yuta Saiga; Masashi Kosaka; Kazuyuki Matsubayashi; Yoshiya Uwatoko
  Journal of Physics: Conference Series, Volume：2462, Number：1, First page：012039, Last page：012039, Mar. 2023, [Reviewed]
  Abstract
  
  The cubic compound YbCo₂Zn₂₀ has huge electronic specific heat coefficient γ=7900 mJ/molK² and its ground state could be located in the vicinity of the quantum critical point. To investigate magnetic ground state, we have carried out muon spin relaxation measurements and confirmed non-magnetic ground state with fluctuating tiny magnetic moment.
  IOP Publishing, Scientific journal
  DOI：https://doi.org/10.1088/1742-6596/2462/1/012039
  DOI ID：10.1088/1742-6596/2462/1/012039, ISSN：1742-6588, eISSN：1742-6596
• Charge-Ordered State and Low-Dimensional Magnetic Fluctuations in Yb5Ge4 Single Crystal　　　　　　　　　　　　　　　
  Shinji Michimura; Masashi Kosaka; Ayumi Machida; Ryosuke Numakura; Ryosuke Iizuka; Susumu Katano; Yoshiki Imai; Naoki Shirakawa; Yuichi Yamasaki; Hironori Nakao; Hitoshi Sato; Shigenori Ueda; Kojiro Mimura
  Journal of the Physical Society of Japan, Volume：90, Number：4, First page：044703, Last page：044703, Apr. 2021, [Reviewed]
  We have successfully grown single crystals of Yb5Ge4 and performed measurements of magnetization, specific heat, electrical resistivity, and Hall effect. Yb5Ge4 is ordered antiferromagnetically at T-N = 1.7K with broad anomalies appearing just above T-N in the magnetic susceptibility and specific heat curves. An evaluation of the effective magnetic moments and magnetic entropy suggest that the ratio of Yb valences in this compound is Yb3+ : Yb2+ = 2 : 3, as also supported by a hard X-ray photoemission spectrum analysis. To study the relations between the physical properties and Yb valence states, we applied an X-ray diffraction anomalous fine structure (DAFS). The obtained DAFS spectra can be interpreted as the formation of a charge-ordered state rather than a valence-fluctuating state, implying the existence of a low-dimensional zigzag chain constructed through magnetic Yb3+ ions. The characteristic features in magnetization and specific heat measurements are most likely due to strong magnetic fluctuations arising from the low-dimensional arrangement of magnetic Yb3+ ions.
  Japan Society of Applied Physics, English, Scientific journal
  DOI：https://doi.org/10.7566/jpsj.90.044703
  DOI ID：10.7566/jpsj.90.044703, ISSN：0031-9015, eISSN：1347-4073, Web of Science ID：WOS:000636748900016
• 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, Volume：89, Number：5, First page：054704, Last page：054704, May 2020, [Reviewed]
  In this study, single crystals of EuZn2Ge2 were grown Itom Ph Ilux. The structure, as determined from single-crystal X-ray diffraction (XRD) data, was ThCr2Si2-type, I4/minm, a = 4.34210(10), c = 10.5766(5)angstrom. The magnetic, thermal, and electronic transport properties of the single crystals were investigated based on their magnetic susceptibility chi(T), isothermal magnetization M(H), specific heat C(T), and electrical resistivity rho(T) measurements, The EuZn2Ge2 compound contains divalent europium and orders antiferromagnetically at T-N1 = 14.9K with a second-order phase transition. In addition, successive transitions were observed at T-N2 = 8.4 K and T-t similar to 5K. At T-N2, the C(T) and chi(T) data indicated a sharp peak, which resembled a lirst-order transition hut exhibited no hysteresis. To verify Whether a structural phase transition occurs at T-N2, we performed low -temperature single -crystal XRD measurements. The XRD pattern did not indicate any structural transition in the crystal lattice, from the tetragonal to a lower symmetry, Instead, changes in the lattice parameter deviations Delta a/a and Delta c/c of the order of 6 x 10(-5), associated with the magnetostriction effect, were observed at approximately T-N2, presumably owing to a magnetic order-order transition from an incommensurate to a commensurate magnetic structure.
  Physical Society of Japan, English, Scientific journal
  DOI：https://doi.org/10.7566/jpsj.89.054704
  DOI ID：10.7566/jpsj.89.054704, ISSN：0031-9015, eISSN：1347-4073, Web of Science ID：WOS:000530838900038
• Single Crystal Growth and Physical Properties of Ytterbium Sulfide KYbS2 with Triangular Lattice
  Ryosuke Iizuka; Shinji Michimura; Ryosuke Numakura; Yoshiya Uwatoko; Masashi Kosaka
  Proceedings of the International Conference on Strongly Correlated Electron Systems (SCES2019), Mar. 2020, [Reviewed]
  Journal of the Physical Society of Japan, International conference proceedings
  DOI：https://doi.org/10.7566/jpscp.30.011097
  DOI ID：10.7566/jpscp.30.011097
• Magnetic and Transport Properties of Rare Earth Zintl Compound Yb8Ge3Sb5
  Masashi Kosaka; Shunsuke Kasuya; Shinji Michimura; Ryosuke Iizuka; Yoshiya Uwatoko
  Proceedings of the International Conference on Strongly Correlated Electron Systems (SCES2019), Mar. 2020, [Reviewed]
  Journal of the Physical Society of Japan, International conference proceedings
  DOI：https://doi.org/10.7566/jpscp.30.011138
  DOI ID：10.7566/jpscp.30.011138
• Magnetic hyperfine field splitting in the Zintl phase Eu2Mg4Si3
  Theresa Block; Ryosuke Numakura; Masashi Kosaka; Shinji Michimura; Rainer Pöttgen
  Zeitschrift für Naturforschung B, Volume：74, Number：5, First page：451, Last page：454, May 2019, [Reviewed]
  
  Eu₂Mg₄Si₃ ≡ (2Eu²⁺)(4Mg²⁺)(3Si⁴⁻) is an electron-precise Zintl phase. Its Hf₂Co₄P₃-type structure contains three crystallographically independent europium sites. The divalent state of europium was manifested through ¹⁵¹Eu Mössbauer spectroscopy. In the paramagnetic regime (T = 78 K) the isomer shifts range from −9.16 to −11.29 mm s⁻¹. Eu₂Mg₄Si₃ shows complex magnetic hyperfine field splitting at T = 5.7 K with a superposition of three subspectra with magnetic hyperfine fields of 5.4 (Eu2), 20.4 (Eu1) and 22.4 (Eu3) T.
  Walter de Gruyter GmbH, Scientific journal
  DOI：https://doi.org/10.1515/znb-2019-0055
  DOI ID：10.1515/znb-2019-0055, ISSN：0932-0776, eISSN：1865-7117
• Effects of Fe doping on anomalous specific heat and XAFS oscillation in antiferromagnetic metal Mn3Si
  H. Hiraka; K. Ohoyama; M. Kosaka; D. Matsumura
  AIP Advances, Volume：8, Number：10, First page：101424, Last page：101424, Oct. 2018, [Reviewed]
  The specific heat of Mn3-xFexSi was measured over a wide temperature range. Aside from the lattice and electronic specific heat components, another component had a significant contribution to the specific heat at low temperatures in the case of x = 0.2; however, its contribution decreased when x = 1.0. It is observed that the net component was retained at temperatures significantly higher than TN for both x. The XAFS spectra of the Mn K-edge for x = 0 not only indicated a smooth structure near the edge, but also an unusually small amplitude in the extended high energy region; however, these features disappeared with Fe doping. The specific heat and XAFS data were discussed in terms of the charge degree of freedom or electronic inhomogeneity.
  AIP Publishing, Scientific journal
  DOI：https://doi.org/10.1063/1.5042639
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85054921923&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=85054921923&origin=inward
  DOI ID：10.1063/1.5042639, eISSN：2158-3226, SCOPUS ID：85054921923
• Single crystal growth and physical properties of the new ternary compound Eu2Mg4Si3　　　　　　　　　　　　　　　
  Ryosuke Numakura; Ryosuke Iizuka; Shinji Michimura; Susumu Katano; Masashi Kosaka
  Physica B: Condensed Matter, Volume：536, First page：262, Last page：266, May 2018, [Reviewed]
  We have studied the magnetic and electrical properties of new ternary europium magnesium silicide Eu2Mg4Si3. The single crystalline Eu2Mg4Si3 has been prepared by the Mg self-flux method. The compound crystalizes in the hexagonal Hf2Co4P3-type structure with space group P6¯2m with unit cell parameters a=14.78(3)Å and c=4.434(6)Å. Magnetic, electrical, and thermal properties indicate that the system undergoes two successive phase transitions, occurring at TN1=9.6K and TN2=8.4K. The estimated effective magnetic moment is close to the moment of free Eu2+ ion. The electrical resistivity data ρ(T) for Eu2Mg4Si3 show a metallic-like behavior from room temperature down to about 100 K. However, the ρ(T) data exhibit a notable upturn below 80 K and a maximum around TN1 and then suddenly decrease with decreasing temperature. These features are strongly suppressed by applying magnetic fields and a metallic temperature dependence eventually exhibits over the whole temperature range in a magnetic field of 30 kOe. Such behavior is observed in some magnetoresistive compounds.
  Elsevier B.V., English, Scientific journal
  DOI：https://doi.org/10.1016/j.physb.2017.11.030
  DOI ID：10.1016/j.physb.2017.11.030, ISSN：0921-4526, SCOPUS ID：85037053157
• Influence of Pt substitution on magnetic properties of multipolar ordering compounds Ce(Pd,Pt)3S4　　　　　　　　　　　　　　　
  S. Michimura; Ushio Nishikawa; Akihide Shimizu; Masashi Kosaka; Ryosuke Numakura; Ryosuke Iizuka; Susumu Katano
  Physica B: Condensed Matter, Volume：536, First page：1, Last page：5, May 2018, [Reviewed]
  We have studied the magnetic properties of the multipolar ordering compounds Ce(Pd1−xPtx)3S4 with 0.00 ≤x≤0.53 by means of magnetic susceptibility and magnetization measurements. In CePd3S4, a simultaneous phase transition of the antiferro quadrupolar (AFQ) ordering and ferro magnetic (FM) ordering has been observed at 6.3 K. It has been suggested that the primary order parameter of CePd3S4 is the quadrupole moments, and it has not been understood why the FM ordering occurs at very high temperature which is almost the same magnetic transition temperature of GdPd3S4. GdPd3S4 shows an antiferromagnetic (AFM) transition at 5.8 K. With increasing Pt substitution in CePd3S4, the FM transition temperature TC(x) is rapidly suppressed to 2.4 K for x≃0.3 and approaches asymptotically to 1.9K(x=0.53). The results of magnetization curve suggest that the ordered state below TC(x) remains FM and AFQ ordered state for the whole range of x. For x≥0.29, TC(x) reaches at around 2 K, a new AFM transition was observed at TN(x) ≃7K. We determined the T−x phase diagram, and discuss the phase transitions at TC(x) and TN(x). The results suggest the possibility of the presence of the correlation between the magnetic interaction and the quadrupole interaction, and the correlation is not understood based on the previous multipolar model.
  Elsevier B.V., English, Scientific journal
  DOI：https://doi.org/10.1016/j.physb.2017.10.120
  DOI ID：10.1016/j.physb.2017.10.120, ISSN：0921-4526, SCOPUS ID：85034838222
• Magnetic properties of rare-earth sulfide YbAgS2　　　　　　　　　　　　　　　
  Ryosuke Iizuka; Ryosuke Numakura; Shinji Michimura; Susumu Katano; Masashi Kosaka
  Physica B: Condensed Matter, Volume：536, First page：314, Last page：316, May 2018, [Reviewed]
  We have succeeded in synthesizing single-phase polycrystalline samples of YbAgS2 belonging to the tetragonal system with space group I41md. YbAgS2 shows an antiferromagnetic transition at TN=6.6K. The effective magnetic moment is in good agreement with the theoretical value for Yb3+ free ion. A broad anomaly is observed just above TN in the temperature dependence of magnetic susceptibility. The entropy released at TN is only about half of Rln2 expected for a Kramers doublet ground state. We consider that these phenomena are due to the existence of short-range magnetic correlations rather than the partial screening of the Yb moments by conduction electrons via the Kondo effect.
  Elsevier B.V., English, Scientific journal
  DOI：https://doi.org/10.1016/j.physb.2017.09.049
  DOI ID：10.1016/j.physb.2017.09.049, ISSN：0921-4526, SCOPUS ID：85029585828
• Purification of commercial yttrium metal: Removal of fluorine　　　　　　　　　　　　　　　
  A. Takenouchi; T. Otomo; K. Niwa; M. Sakai; Y. Saito; T. Kirigane; M. Kosaka; S. Michimura; S. Hasegawa; O. Nakamura
  Journal of Crystal Growth, Volume：468, First page：701, Last page：704, Jun. 2017, [Reviewed]
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/j.jcrysgro.2016.11.091
  DOI ID：10.1016/j.jcrysgro.2016.11.091, ISSN：0022-0248
• Magnetic and transport properties of the narrow-gap semiconductor Yb5Si4　　　　　　　　　　　　　　　
  Masashi Kosaka; Shingo Ottomo; Ayumi Machida; Tomoyuki Kirigane; Ryosuke Numakura; Susumu Katano; Shinji Michimura
  INTERNATIONAL CONFERENCE ON STRONGLY CORRELATED ELECTRON SYSTEMS 2014 (SCES2014), Volume：592, 2015, [Reviewed]
  We report the synthesis and basic properties of the binary compound Yb5Si4. In this compound, Yb ions occupy three different crystallographic sites, the multiplicity of which is represented by Ybl : Yb2 : Yb3 = 1 : 2 : 2. The estimated effective magnetic moment and magnetic entropy can be explained by the proportion of Yb valence states, Yb3+ : Yb2+ = 2 : 3. This result suggests the possibility that Yb3+ ions occupy either Yb2 or Yb3 site. Yb5Si4 undergoes an antiferromagnetic transition at T-N = 1.7 K. The extended high temperature tail in the temperature dependence of the specific heat just above T-N has been observed. Yb5Si4 also exhibits the broad maximum peak around 2.3 K in the magnetic susceptibility, corresponding to the specific heat anomaly. We propose that these anomalies are possible to originate from magnetic fluctuations caused by low-dimensional Yb3+ networks. Electrical resistivity measurements on Yb5Si4 reveal semiconducting behavior at all temperatures. The small energy gap Delta = 430 K has been obtained at room temperature estimated by the thermal activation model. The energy gap gradually decreases with decreasing temperature, and reaches about 3 K at low temperatures.
  IOP PUBLISHING LTD, English, International conference proceedings
  DOI：https://doi.org/10.1088/1742-6596/592/1/012092
  DOI ID：10.1088/1742-6596/592/1/012092, ISSN：1742-6588, Web of Science ID：WOS:000352239200092
• Field-induced long-range magnetic order in the spin-singlet ground-state system YbAl3C3: Neutron diffraction study
  D. D. Khalyavin; D. T. Adroja; P. Manuel; A. Daoud-Aladine; M. Kosaka; K. Kondo; K. A. McEwen; J. H. Pixley; Qimiao Si
  Physical Review B, Volume：87, Number：22, Jun. 2013, [Reviewed]
  American Physical Society (APS), Scientific journal
  DOI：https://doi.org/10.1103/physrevb.87.220406
  DOI ID：10.1103/physrevb.87.220406, ISSN：1098-0121, eISSN：1550-235X
• High-pressure studies of DyB2C2
  Hiroki Yamauchi; Toyotaka Osakabe; Masashi Kosaka; Eiichi Matsuoka; Hideya Onodera
  Journal of the Korean Physical Society, Volume：62, Number：12, First page：2084, Last page：2087, Jun. 2013, [Reviewed]
  Korean Physical Society, Scientific journal
  DOI：https://doi.org/10.3938/jkps.62.2084
  DOI ID：10.3938/jkps.62.2084, ISSN：0374-4884, eISSN：1976-8524
• Strongly hybridized electronic structure of YbAl2: An angle-resolved photoemission study
  M. Matsunami; T. Hajiri; H. Miyazaki; M. Kosaka; S. Kimura
  Physical Review B, Volume：87, Number：16, Apr. 2013, [Reviewed]
  American Physical Society (APS), Scientific journal
  DOI：https://doi.org/10.1103/physrevb.87.165141
  DOI ID：10.1103/physrevb.87.165141, ISSN：1098-0121, eISSN：1550-235X
• Ultrasonics in the two-dimensional dimer spin system YbAl3C3
  Y Nakanishi; F Shichinomiya; M Koseki; G Koseki; R Kashiwazaki; K Deto; M Nakamura; M Yoshizawa; M Kosaka
  Journal of Physics: Conference Series, Volume：400, Number：3, First page：032062, Last page：032062, Dec. 2012, [Reviewed]
  IOP Publishing, Scientific journal
  DOI：https://doi.org/10.1088/1742-6596/400/3/032062
  DOI ID：10.1088/1742-6596/400/3/032062, ISSN：1742-6588, eISSN：1742-6596
• Uniaxial-Pressure Control of Magnetic Phase Transitions in a Frustrated Magnet CuFe1-xGaxO2 (x=0, 0.018)　　　　　　　　　　　　　　　
  Taro Nakajima; Setsuo Mitsuda; Keiichiro Takahashi; Keisuke Yoshitomi; Kazuya Masuda; Chikafumi Kaneko; Yuki Honma; Satoru Kobayashi; Hideaki Kitazawa; Masashi Kosaka; Naofumi Aso; Yoshiya Uwatoko; Noriki Terada; Shuichi Wakimoto; Masayasu Takeda; Kazuhisa Kakurai
  JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Volume：81, Number：9, Sep. 2012, [Reviewed]
  We have investigated effects of applied uniaxial pressure (p) on magnetic phase transitions in a triangular lattice antiferromagnet CuFeO2 (CFO) and a slightly Ga-substituted compound CuFe1-xGaxO2 (CFGO) with x = 0.018. We have performed neutron diffraction, spherical neutron polarimetry, magnetic susceptibility and pyroelectric measurements under p up to 100 MPa applied on the [1 (1) over bar0] surfaces of the single crystal samples. As a result, we have revealed that in both of CFO and CFGO (x = 0.018), the application of p significantly increases the transition temperature from the paramagnetic phase to a collinear incommensurate antiferromagnetic phase, at which these systems exhibit a crystal structural distortion associated with the magnetic ordering. This suggests that the application of p beaks equilateral symmetry of the triangular lattice above the original transition temperature, and partially relieves geometrical spin frustration, which generally suppresses long-range magnetic orderings even at low temperatures. In CFGO (x = 0.018), we have also found that the ferroelectric helimagnetic phase, which originally shows up as an intermediate phase in zero pressure, partly remains down to low temperatures under applied p. These results have demonstrated that uniaxial pressure can be an effective tool to control magnetic phase transitions in frustrated magnets.
  PHYSICAL SOC JAPAN, English, Scientific journal
  DOI：https://doi.org/10.1143/JPSJ.81.094710
  DOI ID：10.1143/JPSJ.81.094710, ISSN：0031-9015, Web of Science ID：WOS:000308305000035
• Photoemission Evidence for Valence Fluctuations and Kondo Resonance in YbAl2　　　　　　　　　　　　　　　
  Masaharu Matsunami; Ashish Chainani; Munetaka Taguchi; Ritsuko Eguchi; Yasutaka Takata; Masaki Oura; Makina Yabashi; Kenji Tamasaku; Yoshinori Nishino; Tetsuya Ishikawa; Masashi Kosaka; Shik Shin
  JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Volume：81, Number：7, Jul. 2012, [Reviewed]
  We use hard x-ray photoemission spectroscopy (HAXPES) to investigate the electronic structure of YbAl2, for which the Yb valence has not been consistently reported to date. The bulk sensitivity and the analytical simplicity provided by the Yb 3d core-level HAXPES allow a reliable determination of the mean valence of Yb ions. For YbAl2, it is evaluated to be +2.20, which remains nearly unchanged below 300 K. The Kondo resonance peak with an extremely high Kondo temperature (above 2000 K) is clearly identified in the valence-band spectra. The results indicate that a coherent Kondo state can be robust even in a nearly divalent system.
  PHYSICAL SOC JAPAN, English, Scientific journal
  DOI：https://doi.org/10.1143/JPSJ.81.073702
  DOI ID：10.1143/JPSJ.81.073702, ISSN：0031-9015, Web of Science ID：WOS:000305899300003
• Magnetic field switching of the charge-density-wave state in the lanthanide intermetallic SmNiC2
  N. Hanasaki; Y. Nogami; M. Kakinuma; S. Shimomura; M. Kosaka; H. Onodera
  Physical Review B, Volume：85, Number：9, Mar. 2012, [Reviewed]
  American Physical Society (APS), Scientific journal
  DOI：https://doi.org/10.1103/physrevb.85.092402
  DOI ID：10.1103/physrevb.85.092402, ISSN：1098-0121, eISSN：1550-235X
• Uniaxial-stress enhancement of spin-driven ferroelectric polarization in a multiferroic CuFe1−xGaxO2
  S Mitsuda; K Yoshitomi; T Nakajima; C Kaneko; H Yamazaki; M Kosaka; N Aso; Y Uwatoko; Y Noda; M Matsuura; N Terada; S Wakimoto; M Takeda; K Kakurai
  Journal of Physics: Conference Series, Volume：340, First page：012062, Last page：012062, Feb. 2012, [Reviewed]
  Delafossite compound CuFeO2 is a spin-driven magneto-electric multiferroic, in which magnetic field-induced or nonmagnetic impurity-induced proper helical magnetic ordering generates a spontaneous electric polarization through the spin-orbit-interaction mediated modulation of Fe 3d-O 2p hybridization. As is expected from spin-lattice tightly coupled character of this system, we found an enhancement of spin-driven ferroelectric polarization under [110] uniaxial stress as spin-mediated piezoelectric effect. Preparing almost mono-domain state for multiferroic CuFe1-xGaxO 2 sample with x=0.035, we have performed polarized neutron diffraction and in-situ ferroelectric polarization measurements to investigate how the helical magnetic structure is modified and how much ferroelectric polarization increases under application of [110] uniaxial stress up to 100 MPa. The uniaxial-stress variation of magnetic structural parameters characterizing helical magnetic ordering suggests decreasing of the ferroelectric polarization according to the calculation on the basis of d-p hybridization mechanism. Therefore, it is suggested that the enhancement of ferroelectric polarization originates not in variation of the magnetic structure but in the enhancement of the d-p hybridization coupling constants.
  IOP Publishing, Scientific journal
  DOI：https://doi.org/10.1088/1742-6596/340/1/012062
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84858593270&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=84858593270&origin=inward
  DOI ID：10.1088/1742-6596/340/1/012062, ISSN：1742-6588, eISSN：1742-6596, SCOPUS ID：84858593270
• Successive Transition in Rare-earth Intermetallic Compound GdNiC2
  N Hanasaki; K Mikami; S Torigoe; Y Nogami; S Shimomura; M Kosaka; H Onodera
  Journal of Physics: Conference Series, Volume：320, First page：012072, Last page：012072, Sep. 2011, [Reviewed]
  IOP Publishing, Scientific journal
  DOI：https://doi.org/10.1088/1742-6596/320/1/012072
  DOI ID：10.1088/1742-6596/320/1/012072, eISSN：1742-6596
• Control of ferroelectric polarization via uniaxial pressure in the spin-lattice-coupled multiferroic CuFe1-xGaxO2　　　　　　　　　　　　　　　
  Taro Nakajima; Setsuo Mitsuda; Takashi Nakamura; Hajime Ishii; Tendai Haku; Yuki Honma; Masashi Kosaka; Naofumi Aso; Yoshiya Uwatoko
  PHYSICAL REVIEW B, Volume：83, Number：22, First page：220101, Jun. 2011, [Reviewed]
  We have demonstrated that ferroelectric polarization in a spin-driven multiferroic CuFe1-xGaxO2 with x = 0.035 can be controlled by the application of uniaxial pressure. Our neutron-diffraction and in situ ferroelectric-polarization measurements have revealed that the pressure dependence of the ferroelectric polarization is explained by repopulation of three types of magnetic domains originating from the trigonal symmetry of the crystal. We conclude that the spin-driven anisotropic lattice distortion and the fixed relationship between the directions of the magnetic modulation wave vector and the ferroelectric polarization are the keys to this spin-mediated piezoelectric effect.
  AMER PHYSICAL SOC, English, Scientific journal
  DOI：https://doi.org/10.1103/PhysRevB.83.220101
  DOI ID：10.1103/PhysRevB.83.220101, ISSN：1098-0121, Web of Science ID：WOS:000291697300001
• Magnetic-Field-Induced Transitions in Spinel GeCo2O4　　　　　　　　　　　　　　　
  Masaaki Matsuda; Takemichi Hoshi; Hiroko Aruga Katori; Masashi Kosaka; Hidenori Takagi
  JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Volume：80, Number：3, Mar. 2011, [Reviewed]
  The spinel GeCo2O4 has the pyrochlore lattice of Co2+ ions, in which the kagome and triangular planes stack alternately along the [111] direction. It shows antiferromagnetic ordering below T-N similar to 21K with a characteristic wave vector of Q(M) = (1/2, 1/2, 1/2). The spin arrangement is ferromagnetic in the kagome and triangular planes and antiferromagnetic between the kagome planes as well as between the triangular planes. GeCo2O4 exhibits a magnetic phase transition at H similar to 4 T. Powder neutron diffraction measurements were performed on GeCo2O4 in ambient and magnetic field. Our results are consistent with the magnetic structure model in which the kagome and triangular planes behave independently in magnetic field, that is, the spin arrangement between the triangular planes becomes ferromagnetic above similar to 4T while retaining the antiferromagnetic arrangement between the kagome planes.
  PHYSICAL SOC JAPAN, English, Scientific journal
  DOI：https://doi.org/10.1143/JPSJ.80.034708
  DOI ID：10.1143/JPSJ.80.034708, ISSN：0031-9015, Web of Science ID：WOS:000288160900037
• Spontaneous strain in ferroquadrupolar phase of TmAu2　　　　　　　　　　　　　　　
  M. Kosaka; Y. Shida; A. Imanari; S. Katano; K. Ohoyama; H. Onodera
  INTERNATIONAL CONFERENCE ON STRONGLY CORRELATED ELECTRON SYSTEMS (SCES 2010), Volume：273, 2011, [Reviewed]
  We present the results of a study of the spontaneous strain accompanied by a ferroquadrupolar ordering in TmAu2. The strain has been investigated by means of thermal expansion, magnetostriction, and neutron diffraction measurements on a single crystalline TmAu2. In the ferroquadrupolar ordered phase, the strain shows a strong enhancement by applying magnetic field. This implies that structural orthorhombic domains caused by the ferroquadrupolar ordering are transformed into a single-domain structure by a magnetic field.
  IOP PUBLISHING LTD, English, International conference proceedings
  DOI：https://doi.org/10.1088/1742-6596/273/1/012137
  DOI ID：10.1088/1742-6596/273/1/012137, ISSN：1742-6588, Web of Science ID：WOS:000291224100137
• Pressure-induced ferromagnetic to antiferromagnetic phase transition in Ce2Ni5C3　　　　　　　　　　　　　　　
  Yamada, Atsushi; Matsubayashi, Kazuyuki; Uwatoko, Yoshiya; Kondo, Kenji; Katano, Susumu; Kosaka, Masashi
  SOLID STATE COMMUNICATIONS, Volume：150, Number：15-16, First page：725, Last page：728, Apr. 2010, [Reviewed]
  We have studied an effect of pressure on the ferromagnetism of Ce2Ni5C3 by ac susceptibility using a newly developed Palm cubic anvil cell up to 5.2 GPa. The ferromagnetic transition temperature of 2.3 K at ambient pressure is suppressed to zero at a critical pressure P similar to 3.8 GPa. Instead, another magnetic phase appears above this pressure. This new magnetic phase is considered to be antiferromagnetic from the result of the magnetic field dependence of the ac susceptibility. (C) 2010 Elsevier Ltd. All rights reserved.
  PERGAMON-ELSEVIER SCIENCE LTD, English, Scientific journal
  DOI：https://doi.org/10.1016/j.ssc.2010.01.036
  DOI ID：10.1016/j.ssc.2010.01.036, ISSN：0038-1098, Web of Science ID：WOS:000276669300008
• Ultrasonic investigation close to quantum critical point in YbTr2Zn20(Tr: Co, Rh, and Ir)
  Y Nakanishi; T Kamiyama; K Ito; M Nakamura; Y Saiga; M Kosaka; Y Uwatoko; M Yoshizawa
  Journal of Physics: Conference Series, Volume：200, Number：1, First page：012142, Last page：012142, Jan. 2010, [Reviewed]
  We performed ultrasonic measurements on high quality single crystals of the Yb-based heavy fermion compounds YbTr2Zn20 (Tr: Co, Rh and Ir) over a temperature range from 200 K to 0.5 K, which seem to be close to a quantum critical point (QCP). A sharp contrast of the temperature dependence of elastic constants was found at low temperature among the three compounds, reflecting the 4f electronic state stemmed from Yb ion. The results indicate that a crystalline electric field (CEF) effect seems to be dominant in the systems YbRh2Zn20 and YbIr2Zn20 at low temperatures. On the other hand, the CEF effect is much less, but an additional effect would be dominant which is most probably ascribable to non Fermi liquid characteristics formed close to the QCP. We discuss briefly each 4f electronic state developed at the low temperatures and physical parameters relating to a renormalized band model in YbTr2Zn20 in the framework of a deformation potential approximation. © 2010 IOP Publishing Ltd.
  IOP Publishing, Scientific journal
  DOI：https://doi.org/10.1088/1742-6596/200/1/012142
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=77957084025&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=77957084025&origin=inward
  DOI ID：10.1088/1742-6596/200/1/012142, ISSN：1742-6588, eISSN：1742-6596, SCOPUS ID：77957084025
• Enhanced Faraday Effect in Magnetic Opal of Spherical Silica Particles　　　　　　　　　　　　　　　
  Norihito Sogoshi; Kazushi Kobayashi; Masashi Kosaka; Susumu Katano; Seiichiro Nakabayashi
  CHEMISTRY LETTERS, Volume：38, Number：11, First page：1044, Last page：1045, Nov. 2009, [Reviewed]
  The Faraday effect of magnetic opal films is studied at the visible wavelength slightly detuned from the Bragg diffraction wavelength. At this wavelength, we can expect the reduced group velocity of light and the enhancement of the Faraday rotation. The magnetic opal was self-assembled from a suspension of magnetic-core/silica-shell spherical particles onto glass substrates using vertical deposition. Despite of the structural disorder in the thick opal film, the optical rotation was enhanced 70 times over that of the structure less bulk at 10 T. The thin film with the highest structural quality shows an enhancement factor of 175. Thus, structure-induced enhancement was explicitly demonstrated.
  CHEMICAL SOC JAPAN, English, Scientific journal
  DOI：https://doi.org/10.1246/cl.2009.1044
  DOI ID：10.1246/cl.2009.1044, ISSN：0366-7022, eISSN：1348-0715, CiNii Articles ID：10025547826, Web of Science ID：WOS:000272854200016
• Elastic constants of the single crystalline Yb based heavy-fermion compound YbCo2Zn20　　　　　　　　　　　　　　　
  Yoshiki Nakanishi; Takuya Fujino; Kankichi Ito; Mitsuteru Nakamura; Masahito Yoshizawa; Yuta Saiga; Masashi Kosaka; Yoshiya Uwatoko
  PHYSICAL REVIEW B, Volume：80, Number：18, First page：184418, Nov. 2009, [Reviewed]
  Ultrasonic measurements have been carried out on the heavy-fermion compound YbCo2Zn20 to investigate the elastic properties and the 4f electric state of Yb ion. A strong temperature dependence at low temperature was found in elastic constants C-11, (C-11-C-12)/2, and C-44 of YbCo2Zn20. Furthermore, the elastic constants are significantly magnetic field dependent at low temperatures. These experimental facts strongly suggest an importance of the highly degenerated 4f low-lying level scheme of Yb ions under a crystalline electric field effect, probably leading to such an extremely large Sommerfeld coefficient of YbCo2Zn20. We argue that the near spherical distribution of neighboring Zn atoms centered at the Yb site is an essential requirement for the formation of such an exotic heavy-fermion system.
  AMER PHYSICAL SOC, English, Scientific journal
  DOI：https://doi.org/10.1103/PhysRevB.80.184418
  DOI ID：10.1103/PhysRevB.80.184418, ISSN：1098-0121, CiNii Articles ID：80020741908, Web of Science ID：WOS:000272310900076
• Elastic property of TbRu4P12under pressure　　　　　　　　　　　　　　　
  Y. Nakanishi; K. Ito; T. Kamiyama; M. Nakamura; M. Yoshizawa; M. Ohashi; G. Oomi; M. Kosaka; C. Sekine; I. Shirotani
  Physica B: Condensed Matter, Volume：404, Number：19, First page：3271, Last page：3274, Oct. 2009, [Reviewed]
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/j.physb.2009.07.098
  DOI ID：10.1016/j.physb.2009.07.098, ISSN：0921-4526
• Ultrasonic study of the Yb-based heavy fermion compound YbRh2Zn20
  Y Nakanishi; K Ito; M Nakamura; Y Saiga; M Kosaka; Y Uwatoko; M Yoshizawa
  Journal of Physics: Conference Series, Volume：150, Number：4, First page：042138, Last page：042138, Mar. 2009, [Reviewed]
  We report ultrasonic measurements on the high quality single crystal of the Yb-based heavy fermion compound YbRh2Zn20 over a temperature range from 200 K to 0.5 K. A shallow, but clear minimum was observed in the temperature dependent elastic constants C11, (C11 - C12)/2 and C44 around 15 K, probably attributed to the ground state and low-lying excited states of Yb3 in the cubic CEF. We discuss the low-temperature elastic properties and possible energy level scheme of localized 4f state of Yb3 ions in YbRh2Zn 20. CEF ground state developed at the low temperatures and physical parameters relating to a quadrupolar moment in YbRh2Zn20 © 2009 IOP Publishing Ltd.
  IOP Publishing, Scientific journal
  DOI：https://doi.org/10.1088/1742-6596/150/4/042138
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=77952501232&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=77952501232&origin=inward
  DOI ID：10.1088/1742-6596/150/4/042138, ISSN：1742-6588, eISSN：1742-6596, SCOPUS ID：77952501232
• Magnetic properties of Sr3-xCaxRu2O7　　　　　　　　　　　　　　　
  Kotaro Iwata; Yoshiyuki Yoshida; Masashi Kosaka; Susumu Katano
  25TH INTERNATIONAL CONFERENCE ON LOW TEMPERATURE PHYSICS (LT25), PART 4, Volume：150, 2009, [Reviewed]
  We report the magnetization data of single crystalline Sr3-xCaxRu2O7 (x = 1.5, 2.0, 3.0) grown by a floating-zone method. In the magnetic phase diagram of this system, a phase with a ferromagnetic correlation (0.5 <= x <= 1.2) adjoins a two-dimensional (2D) metallic and antiferromagnetic phase (1.2 <= x <= 3). In the antiferromagnetic and 2D-metallic phase, the magnetic susceptibilities indicate that the magnetic easy axis changes continuously from the ab-plane to c-axis with increasing Sr content. Our results exhibit that the metamagnetic transition of Ca3Ru2O7, which is on the basis of a tunneling magnetoresistance, shifts to lower field and the transition becomes broad with increasing Sr content. Moreover, the magnetization data at T = 5 K for x = 1.5, 2.0 show a hysteresis, which suggests that the magnetic ground state is a canted antiferromagnetic one in this phase.
  IOP PUBLISHING LTD, English, International conference proceedings
  DOI：https://doi.org/10.1088/1742-6596/150/4/042077
  DOI ID：10.1088/1742-6596/150/4/042077, ISSN：1742-6588, Web of Science ID：WOS:000289891200077
• Magnetoresistivity of YbCo2Zn20 at low temperature　　　　　　　　　　　　　　　
  Yuta Saiga; Kazuyuki Matsubayashi; Tetsuya Fujiwara; Takehiko Matsumoto; Masashi Kosaka; Susumu Katano; Yoshiya Uwatoko
  25TH INTERNATIONAL CONFERENCE ON LOW TEMPERATURE PHYSICS (LT25), PART 4, Volume：150, 2009, [Reviewed]
  We have studied the electrical resistivity of YbCo2Zn20 under magnetic field up to 18T. With applying magnetic field, the contribution of the Kondo interaction to the electrical resistivity is suppressed and the Fermi liquid regime is extended to higher temperature range. Both the T-2 coefficient of the electrical resistivity A and the residual resistivity rho(0) strongly decrease in magnetic field. From the magnetic variation of the resistivity, it has been found that YbCo2Zn20 is classified as a heavy fermion system with small Kondo temperature of similar to 1.0 K.
  IOP PUBLISHING LTD, English, International conference proceedings
  DOI：https://doi.org/10.1088/1742-6596/150/4/042168
  DOI ID：10.1088/1742-6596/150/4/042168, ISSN：1742-6588, eISSN：1742-6596, Web of Science ID：WOS:000289891200168
• Al-27 NMR/NQR Studies of YbAl3C3　　　　　　　　　　　　　　　
  Takeshi Mito; Satoru Tomisawa; Shinji Wada; Hisatomo Harima; Kenjiro Hashi; Tadashi Shimizu; Atsushi Goto; Shinobu Ohki; Yoshiaki Kato; Masashi Kosaka
  JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Volume：78, Number：1, First page：014709, Jan. 2009
  The phase transition at T* = 80 K in YbAl3C3 has been studied by Al-27 nuclear quadrupole resonance (NQR) measurement and nuclear magnetic resonance (NMR) measurement up to 30T. The NQR and NMR spectra reveal clear anomalies just below T*, which provides the first microscopic evidence for symmetry lowering in the low-temperature phase below T*. The transition is characterized by marked changes in the Al-27-NQR frequencies v(Q)'s without significant changes in the lattice parameters. The field dependence of the transition is also investigated. The NMR line exhibits field-induced rapid broadening below T*, which almost vanishes in zero field. Moreover, we found that T* increases by 10K at 30T. These unique magnetic properties are consistent with the scheme that the microscopic mechanism underlying the phase transition involves Yb-4f electrons rather than the scheme of a simple structural phase transition.
  PHYSICAL SOC JAPAN, English, Scientific journal
  DOI：https://doi.org/10.1143/JPSJ.78.014709
  DOI ID：10.1143/JPSJ.78.014709, ISSN：0031-9015, Web of Science ID：WOS:000263287200035
• Structural Phase Transition in the Spin Gap System YbAl3C3　　　　　　　　　　　　　　　
  Takeshi Matsumura; Toshiya Inami; Masashi Kosaka; Yoshiaki Kato; Takaki Inukai; Akira Ochiai; Hironori Nakao; Youichi Murakami; Susumu Katano; Hiroyuki S. Suzuki
  JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Volume：77, Number：10, First page：103601, Oct. 2008
  The unresolved phase transition at 80 K in YbAl3C3 has been studied by X-ray diffraction. It has been confirmed that the transition is a structural one with atomic displacement. Superlattice reflections that appear below 80 K show that the crystal structure changes from hexagonal to orthorhombic. From the reflection conditions, we conclude that the space group in the low temperature phase is Pbca, where all the atoms occupy the general 8c site. By fitting the observed intensities, we present two possible models of atomic displacement. The displacement results in the deformation of the triangular lattice of Yb spins. which is considered to be responsible for the formation of a spin-singlet,round state at low temperatures.
  PHYSICAL SOC JAPAN, English, Scientific journal
  DOI：https://doi.org/10.1143/JPSJ.77.103601
  DOI ID：10.1143/JPSJ.77.103601, ISSN：0031-9015, Web of Science ID：WOS:000260233500004
• Structural Distortion and Physical Properties in Double-Layered Ruthenate Sr3-xCaxRu2O7　　　　　　　　　　　　　　　
  Kotaro Iwata; Yoshiyuki Yoshida; Masashi Kosaka; Susumu Katano
  JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Volume：77, Number：10, First page：104716, Oct. 2008
  We have investigated the structural, magnetic, and electronic properties of single-crystalline Sr3-xCax-Ru2O7 (0 <= x <= 3) grown by a floating-zone method. The results of X-ray diffraction, magnetic susceptibility, specific heat, and electrical resistivity measurements reveal that this system shows a novel phase diagram. With increasing Ca content, the enhanced paramagnetism of Sr3Ru2O7 is Suppressed, and a phase with a ferromagnetic correlation (0.5 less than or similar to x less than or similar to 1.2) emerges. This phase adjoins an antiferromagnetic two-dimensional metallic phase (1.2 less than or similar to x <= 3.0). At the border between these two phases, discontinuous changes in the lattice parameters are observed. In the ferromagnetically correlated phase, the density of states is significantly enhanced. In the anti ferromagnetic phase. the magnetic easy axis changes continuously from the c-axis to the ab-plane with increasing Ca content. These magnetic and electronic properties are strongly coupled with structural distortions such as the rotation and filling of the RuO6 octahedra of this system.
  PHYSICAL SOC JAPAN, English, Scientific journal
  DOI：https://doi.org/10.1143/JPSJ.77.104716
  DOI ID：10.1143/JPSJ.77.104716, ISSN：0031-9015, Web of Science ID：WOS:000260233500043
• Pressure-induced magnetic transition in a single crystal of YbCo2Zn20　　　　　　　　　　　　　　　
  Yuta Saiga; Kazuyuki Matsubayashi; Tetsuya Fujwara; Masashi Kosaka; Susumu Katano; Masato Hedo; Takehiko Matsumoto; Yoshiya Uwatoko
  JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Volume：77, Number：5, First page：053710, May 2008
  We have measured the electrical resistivity of a single crystal of YbCo2Zn20 at pressures up to 2.37 GPa and at temperatures from 50 mK to 300 K. Above a critical pressure P. (similar to I GPa), we have found a resistivity anomaly at T-M (similar to 0.15 K at 1 GPa) that increases with the pressure. At the ambient pressure, the system shows a nonmagnetic ground state described by the Fermi-liquid model. The T-2 coefficient of the electrical resistivity A strongly increases with the pressure upon approaching Pc. However, in the vicinity of P,, the temperature dependence of the resistivity deviates from the Fermi-liquid description. These observations suggest that the application of hydrostatic pressure induces a magnetically ordered state for P >= P-c and T <= T-M.
  PHYSICAL SOC JAPAN, English, Scientific journal
  DOI：https://doi.org/10.1143/JPSJ.77.053710
  DOI ID：10.1143/JPSJ.77.053710, ISSN：0031-9015, Web of Science ID：WOS:000255998200012
• Spin-singlet ground state in the two-dimensional frustrated triangular lattice: YbAl3C3　　　　　　　　　　　　　　　
  Yoshiaki Kato; Masashi Kosaka; Hiromi Nowatari; Yuta Saiga; Atsushi Yamada; Takuya Kobiyama; Susumu Katano; Kenji Ohoyama; Hiroyuki S. Suzuki; Naofumi Aso; Kazuaki Iwasa
  JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Volume：77, Number：5, First page：053701, May 2008
  We present the highly frustrated phenomena observed in YbAl3C3 with a spin gap. The inelastic neutron spectra of low-lying magnetic excitations at low temperatures are quite similar to those of SrCU2(BO3)(2) and (CuCl)LaNb2O7 that exhibit a dimer ground state in a two-dimensional quantum spin system. The structure of the first excited triplet state is directly clarified by inelastic neutron scattering experiments with a higher energy resolution. Furthermore, it becomes clear that the characteristic magnetic excitations remain within a high-temperature region. The result of the specific heat measurement also shows an anomaly associated with the formation of dimerized Yb ions. We conclude that a long-range magnetic order is suppressed by a large geometrical spin frustration, resulting in the stabilization of the dimer ground state.
  PHYSICAL SOC JAPAN, English, Scientific journal
  DOI：https://doi.org/10.1143/JPSJ.77.053701
  DOI ID：10.1143/JPSJ.77.053701, ISSN：0031-9015, Web of Science ID：WOS:000255998200003
• NQR investigation on multipolar ordering systems　　　　　　　　　　　　　　　
  T. Mito; S. Tomisawa; S. Masaki; M. Takemura; S. Wada; H. Harima; Y. Kato; M. Kosaka; D. Kikuchi; H. Sato; H. Sugawara; N. Takeda; G. -q. Zheng
  PHYSICA B-CONDENSED MATTER, Volume：403, Number：5-9, First page：1633, Last page：1635, Apr. 2008
  We have carried out nuclear quadrupolar resonance (NQR) measurements on SmRu4P12 and YbAl3C3, both of which have attracted much interest in terms of multipolar ordering. Although no structural anomalies have been detected by diffraction experiments so far, the NQR resonance frequencies v(Q)'s of both compounds show marked anomalies just below each phase transition temperature, which probably probes the order parameters. The results provide important information to shed light on the ordered structures in the low temperature phases of these compounds. (C) 2007 Elsevier B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/j.physb.2007.10.206
  DOI ID：10.1016/j.physb.2007.10.206, ISSN：0921-4526, Web of Science ID：WOS:000254689900326
• Magnetic and electrical properties of single crystalline Sr3-xCaxRu2O7　　　　　　　　　　　　　　　
  K. Iwata; Y. Yoshida; M. Kosaka; S. Katano
  PHYSICA B-CONDENSED MATTER, Volume：403, Number：5-9, First page：1596, Last page：1597, Apr. 2008
  We have successfully grown single crystalline Sr3-xCaxRu2O7 with the range of 2.0 <= x <= 3.0 using the floating-zone method. All compounds show orthorhombic symmetry in this substitution range, but the difference between lattice constants a and b decreases with increasing Sr concentration and becomes almost zero at x = 2.0. Characteristic temperatures, which correspond to antiferromagnetic ordering and structural transition, decrease with increasing Sr concentration. The value of the magnetic susceptibility below 30K increases with increasing Sr concentration. The temperature dependence of the electrical resistivity revealed that Sr substitution significantly suppresses the highly anisotropic electric structure of Ca3Ru2O7. (C) 2007 Elsevier B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/j.physb.2007.10.209
  DOI ID：10.1016/j.physb.2007.10.209, ISSN：0921-4526, Web of Science ID：WOS:000254689900311
• NMR study of YbAl3C3 in high magnetic field　　　　　　　　　　　　　　　
  Satoru Tomisawa; Takeshi Mito; Shinji Wada; Kenjiro Hashi; Tadashi Shimizu; Atsushi Goto; Shinobu Ohki; Yoshiaki Kato; Masashi Kosaka
  JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Volume：77, First page：291, Last page：293, Jan. 2008, [Reviewed]
  We have carried out Al-27 nuclear magnetic resonance (NMR) measurements on YbAl3C3. The obtained NMR line is well decomposed into two powder pattern spectra characterized by the nuclear magnetic resonance (NQR) frequency nu(Q) = 3.55MHz (Al 2d-site) and 0.35MHz (Al 4f-site). About the transition at exceptionally high temperature T* = 80K, it was found that the NMR line becomes broadened rapidly just below T*, and T* increases by about 10K at the field of 30 Tesla. Analogous phenomena are commonly seen in many quadrupolar ordering systems, implying that the transition in YbAl3C3 is associated with the quadrupolar order.
  PHYSICAL SOC JAPAN, English, Scientific journal
  DOI：https://doi.org/10.1143/JPSJS.77SA.291
  DOI ID：10.1143/JPSJS.77SA.291, ISSN：0031-9015, ORCID：55927248, Web of Science ID：WOS:000209384500064
• Unusual enhancement of magnetization by pressure in the antiferro-quadrupole-ordered phase in CeB6　　　　　　　　　　　　　　　
  Suguru Ikeda; Masafumi Sera; Shingo Hane; Yoshiya Uwatoko; Masashi Kosaka; Satoru Kunii
  JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Volume：76, Number：6, Jun. 2007, [Reviewed]
  The effect of pressure on CeB6 was investigated by the measurement of the magnetization (M) under pressure, and we obtained the following results. The effect of pressure on M in phase I is very small. By applying pressure, T-Q is enhanced, but T-N and the critical field from the antiferromagnetic (AFM) phase III to the anti ferro-quadrupole (AFQ) phase II (H-c(III-II)) are suppressed, as previously reported. The magnetization curve in phase III shows the characteristic shoulder at H similar to H-c(III-II)/2 at ambient pressure. This shoulder becomes much more pronounced by applying pressure. Both H - H-c(III-II) and the magnetic field, where a shoulder is seen in the magnetization curve in phase III, are largely suppressed by pressure. In phase II, the M-T curve at a low magnetic field exhibits an unusual concave temperature dependence below T-Q down to T-N. Thus, we found that the lower the magnetic field, the larger the enhancement of M in both phases III and II. To clarify the origin of the unusual pressure effect of M, we performed a mean-field calculation for the 4-sublattice model using the experimental results of dT(Q)/dP > 0 and dT(N)/dP < 0 and assuming the positive pressure dependence of the T-xyz-antiferro-octupole (AFO) interaction. The characteristic features of the pressure effect of M obtained by the experiments could be reproduced well by the mean-field calculation. We found that the origin of the characteristic effect of pressure on CeB6 is the change in the subtle balance between the AFM interaction and the magnetic field-induced-effective FM interaction induced by the coexistence of the O-xy-AFQ and T-xyz-AFO interactions under pressure.
  PHYSICAL SOC JAPAN, English, Scientific journal
  DOI：https://doi.org/10.1143/JPSJ.76.064716
  DOI ID：10.1143/JPSJ.76.064716, ISSN：0031-9015, Web of Science ID：WOS:000247443000043
• Canted antiferromagnetic ground state in Sr3Ir2O7
  I Nagai; Y Yoshida; S I Ikeda; H Matsuhata; H Kito; M Kosaka
  Journal of Physics: Condensed Matter, Volume：19, Number：13, First page：136214, Last page：136214, Apr. 2007, [Reviewed]
  IOP Publishing, Scientific journal
  DOI：https://doi.org/10.1088/0953-8984/19/13/136214
  DOI ID：10.1088/0953-8984/19/13/136214, ISSN：0953-8984, eISSN：1361-648X
• Pressure effect on transport property of YbMn2Ge2　　　　　　　　　　　　　　　
  Y. Saiga; T. Fujiwara; N. Kurita; M. Hedo; M. Kosaka; Y. Uwatoko
  Journal of Magnetism and Magnetic Materials, Volume：310, Number：2, First page：1877, Last page：1878, Mar. 2007, [Reviewed]
  Electrical resistivities of YbMn2 Ge2 were measured at several pressures in a temperature range from 2 K to room temperature. In low temperature region below 100 K, temperature dependence of the resistivity shows significant change between 2.0 and 4.0 GPa. Under 4.0 GPa, anomalies of the resistivity were observed at (Tt 3 ∼) 21.6 K and (Tt 4 ∼) 7.1 K. There is a fair possible that they originated from novel magnetic phase transitions of Yb or Mn sublattice. With increasing pressure, Tt 4 increases linearly. In contrast to the pressure dependence of Tt 4, Tt 3 decreases linearly. © 2006 Elsevier B.V. All rights reserved.
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/j.jmmm.2006.10.674
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=33847284554&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=33847284554&origin=inward
  DOI ID：10.1016/j.jmmm.2006.10.674, ISSN：0304-8853, SCOPUS ID：33847284554
• Magnetic properties of single crystal of cobalt spinel GeCo2O4　　　　　　　　　　　　　　　
  T. Hoshi; H. Aruga Katori; M. Kosaka; H. Takagi
  Journal of Magnetism and Magnetic Materials, Volume：310, Number：2, First page：e448, Last page：e450, Mar. 2007, [Reviewed]
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/j.jmmm.2006.10.845
  DOI ID：10.1016/j.jmmm.2006.10.845, ISSN：0304-8853
• Thermopower of double-layered ruthenate Ca3Ru2O7　　　　　　　　　　　　　　　
  K. Iwata; M. Kosaka; S. Katano; N. Mori; Y. Yoshida; N. Shirakawa
  JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, Volume：310, Number：2, First page：1125, Last page：1127, Mar. 2007, [Reviewed]
  We measured temperature dependence of in-plane and inter-plane thermopower S-ab and S-c of single crystalline Ca3Ru2O7. The thermopower measurements were carried out by the low-frequency (33 mHz) AC heating method. Large anisotropy between S-ab and S, was observed, and its ratio (S-ab/S-c) is about 15 at 300 K. The sign Of S-ab changes from positive to negative value at the structural transition temperature of 48 K, indicating a reconstruction of Fermi surface. The behavior Of Sab can be explained by the results of the electrical resistivity and Hall coefficient. On the other hand, S-c shows a rather complex behavior. (c) 2006 Elsevier B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/j.jmmm.2006.10.310
  DOI ID：10.1016/j.jmmm.2006.10.310, ISSN：0304-8853, ORCID：45787742, Web of Science ID：WOS:000247618700196
• Magnetic Behavior of the Bilayer Manganese Oxide (Pr0.6La0.4)1.2Sr1.8Mn2O7under Pressure　　　　　　　　　　　　　　　
  Y. Nakanishi; M. Matsukawa; M. Yoshizawa; M. Kosaka; N. Môri; M. Apostu; R. Suryanarayanan; A. Revcolecschi
  Journal of the Physical Society of Japan, Volume：76, Number：Suppl.A, First page：106, Last page：107, Jan. 2007, [Reviewed]
  Physical Society of Japan, English, Scientific journal
  DOI：https://doi.org/10.1143/jpsjs.76sa.106
  DOI ID：10.1143/jpsjs.76sa.106, ISSN：0031-9015, eISSN：1347-4073, CiNii Articles ID：160000037369
• Effect of Uniaxial Strain on Verwey Transition in Magnetite　　　　　　　　　　　　　　　
  Yasuo Nagasawa; Masashi Kosaka; Susumu Katano; Nobuo Mori; Sakae Todo; Yoshiya Uwatoko
  JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Volume：76, First page：110, Last page：111, Jan. 2007, [Reviewed]
  We present a study on magnetization in a single crystal of magnetite under uniaxial strain applied along the [1 1 0] direction using a SQUID magnetometer. An abrupt change in magnetization was observed at the metal-insulator transition temperature T-V (Verwey transition temperature). We observed that T-V increased with increasing uniaxial compression. The pressure coefficient dT(V)/dP was obtained to be 1.6 +/- 0.1 K/kbar. The result obtained is different from that obtained under hydrostatic pressure, which showed that T-V decreases with increasing pressure.
  PHYSICAL SOC JAPAN, English, Scientific journal
  DOI：https://doi.org/10.1143/JPSJS.76SA.110
  DOI ID：10.1143/JPSJS.76SA.110, ISSN：0031-9015, Web of Science ID：WOS:000209124900047
• Effect of pressure on the electrical resistivity of YbAl2　　　　　　　　　　　　　　　
  Hiromi Nowatari; Yuta Saiga; Yoshiaki Kato; Kotaro Iwata; Susumu Katano; Tetsuya Fujiwara; Yoshiya Uwatoko; Masashi Kosaka
  JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Volume：76, First page：80, Last page：81, Jan. 2007, [Reviewed]
  We report the electrical resistivity and specific heat of the intermediate-valence intermetallic compound YbAl2. A single-crystalline YbAl2 was synthesized by the Li-flux-growth technique. Electrical resistivity measurements were performed under high pressures up to 2.3 GPa. The value of the electrical resistivity increases with increasing pressure. This behavior is attributed to the gradual increase of the Yb valence in YbAl2.
  PHYSICAL SOC JAPAN, English, Scientific journal
  DOI：https://doi.org/10.1143/JPSJS.76SA.80
  DOI ID：10.1143/JPSJS.76SA.80, ISSN：0031-9015, Web of Science ID：WOS:000209124900035
• Pressure effect on the long-range order in CeB6　　　　　　　　　　　　　　　
  M. Sera; S. Ikeda; H. Iwakubo; Y. Uwatoko; S. Hane; M. Kosaka; S. Kunii
  Physica B: Condensed Matter, Volume：383, Number：1, First page：37, Last page：38, Aug. 2006, [Reviewed]
  The pressure effect of CeB6 was investigated. The pressure dependence of the Néel temperature, TN and the critical field from the antiferro-magnetic phase III to antiferro-quadrupolar phase II, HcIII - II of CeB6 exhibits the unusual pressure dependence that the suppression rate of HcIII - II is much larger than that of TN. In order to explain this unusual result, we have performed the mean field calculation for the 4-sublattice model assuming that the pressure dependence of TN, the antiferro-octupolar and quadrupolar temperatures, Toct and TQ as follows; d TN / d P < 0, d Toct / d P > d TQ / d P > 0 and could explain the unusual pressure dependence of TN and HcIII - II. © 2006 Elsevier B.V. All rights reserved.
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/j.physb.2006.03.046
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  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=33746552817&origin=inward
  DOI ID：10.1016/j.physb.2006.03.046, ISSN：0921-4526, SCOPUS ID：33746552817
• Magnetic properties of the bilayer manganese oxide (Pr0.6La0.4)1.2Sr1.8Mn2O7 under pressure　　　　　　　　　　　　　　　
  Y. Nakanishi; T. Tanizawa; M. Oikawa; M. Matsukawa; M. Yoshizawa; M. Apostu; R. Suryanarayanan; A. Revcolevschi; M. Kosaka; N. Môri
  Solid State Communications, Volume：138, Number：9, First page：441, Last page：443, Jun. 2006, [Reviewed]
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/j.ssc.2006.04.015
  DOI ID：10.1016/j.ssc.2006.04.015, ISSN：0038-1098
• Uniaxial Strain Effect on TV and Electrical Resistivity in Magnetite (Fe3O4)　　　　　　　　　　　　　　　
  Yasuo Nagasawa; Ryohei Hara; Toshiaki Seino; Masashi Kosaka; Nobuo Môri; Sakae Todo; Yoshiya Uwatoko
  AIP Conference Proceedings, Volume：850, First page：1267, Last page：+, 2006, [Reviewed]
  Magnetization and electrical resistivity studies are reported for a single crystal of magnetite under uniaxial strain applied along the [110] and [100] directions. The metal-insulator transition temperature, T-V, shifted to higher temperatures with increasing uniaxial compression which is opposite to the result obtained under hydrostatic pressure. Furthermore, the electrical resistivity was found to increase at temperatures below T-V, and to decrease at temperatures above T-V, with increasing uniaxial compression. Differences between the present results and those under hydrostatic pressure are discussed.
  AIP, English, International conference proceedings
  DOI：https://doi.org/10.1063/1.2355167
  DOI ID：10.1063/1.2355167, ISSN：0094-243X, Web of Science ID：WOS:000243396400576
• Thermal Expansion and Magnetostriction in YbInCu4 Under High Pressure　　　　　　　　　　　　　　　
  Y. Saiga; T. Nakano; M. Hedo; Y. Uwatoko; M. Kosaka; N. Môri; T. Goto; K. Yoshimura
  AIP Conference Proceedings, Volume：850, First page：1177, Last page：1178, 2006, [Reviewed]
  YbInCu4 undergoes a first-order isostructural valence transition at TV = 42 K, which is accompanied by a 0.5% volume increase due to cooling. In order to elucidate the valence transition, both the linear thermal expansion and magnetostriction, ΔL/L, of a YbInCu4 single crystal were measured using strain gauges under high pressures of up to 3.0 GPa and a magnetic field of up to 18 T. The abrupt volume change during the valence transition was confirmed to decrease linearly with TV under a high pressure. It was also observed that TV was suppressed upon application of a magnetic field. On the basis of the results, we have established a T-P-B phase diagram for the first-order valence transition in YbInCu4. © 2006 American Institute of Physics.
  AIP, International conference proceedings
  DOI：https://doi.org/10.1063/1.2355123
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=33947525098&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=33947525098&origin=inward
  DOI ID：10.1063/1.2355123, ISSN：0094-243X, eISSN：1551-7616, SCOPUS ID：33947525098
• Electrical and magnetic properties of Ce2Ni5C3　　　　　　　　　　　　　　　
  Yoshiaki Kato; Masashi Kosaka; Nobuo Mori
  LOW TEMPERATURE PHYSICS, PTS A AND B, Volume：850, First page：1099, Last page：+, 2006, [Reviewed]
  The Ce2Ni5C3 compound having a tetragonal La2Ni5C3-type Structure with the space group P4/mbm has been prepared using the standard arc melting technique. The X-ray powder diffraction patterns showed that the sample was singlephase. From the magnetic measurements, the Ce2Ni5C3 compound was found to be a ferromagnet having an ordering temperature T-C = 2.3 K. The magnetic susceptibility obeyed a Curie-Weiss law with a Weiss temperature Theta(w) = 2.0 K. The effective magnetic moment estimated from the Curie constant was mu(eff) =1.99 mu(B)/Ce, and the saturation value of the magnetization at 2.0K was 1.4 mu(B)/Ce. The temperature dependence of the specific heat and electrical resistivity showed anomalous behavior accompanied by a magnetic phase transition.
  AMER INST PHYSICS, English, International conference proceedings
  ISSN：0094-243X, Web of Science ID：WOS:000243396400497
• Possible high TQ in YbAl3C3 with 4f 13 system　　　　　　　　　　　　　　　
  Masashi Kosaka; Yoshiaki Kato; Chieko Araki; Nobuo Môri; Yoshiki Nakanishi; Masahito Yoshizawa; Kenji Ohoyama; Catalin Martin; Stanley W. Tozer
  Journal of the Physical Society of Japan, Volume：74, Number：9, First page：2413, Last page：2416, Sep. 2005, [Reviewed]
  We report the highest transition temperature of quadrupolar ordering [TQ] in YbAl3C3, where a distinct anomaly is observed by specific heat and ultrasonic measurements at 80 K. Magnetization measurements show only a very slight change and no magnetic or structural phase transitions can be observed by neutron diffraction measurements in this temperature range. Therefore, we believe that YbAl3C3 shows an antiferroquadrupolar ordering with the highest TQ found to date and is the first realization of this ordering beyond liquid nitrogen temperatures for rare-earth and actinide intermetallic compounds. ©2005 The Physical Society of Japan.
  English, Scientific journal
  DOI：https://doi.org/10.1143/JPSJ.74.2413
  DOI ID：10.1143/JPSJ.74.2413, ISSN：0031-9015, SCOPUS ID：25144492665
• Highest conductivity oxide SrMoO3 grown by a floating-zone method under ultralow oxygen partial pressure
  Ichiro Nagai; Naoki Shirakawa; Shin-ichi Ikeda; Ryusuke Iwasaki; Hiroshi Nishimura; Masashi Kosaka
  Applied Physics Letters, Volume：87, Number：2, First page：024105, Last page：024105, Jul. 2005, [Reviewed]
  AIP Publishing, Scientific journal
  DOI：https://doi.org/10.1063/1.1992671
  DOI ID：10.1063/1.1992671, ISSN：0003-6951, eISSN：1077-3118
• Quasi-two-dimensional metallic ground state ofCa3Ru2O7
  Yoshiyuki Yoshida; Ichiro Nagai; Shin-Ichi Ikeda; Naoki Shirakawa; Masashi Kosaka; Nobuo Môri
  Physical Review B, Volume：69, Number：22, Jun. 2004, [Reviewed]
  American Physical Society (APS), Scientific journal
  DOI：https://doi.org/10.1103/physrevb.69.220411
  DOI ID：10.1103/physrevb.69.220411, ISSN：1098-0121, eISSN：1550-235X
• High-field magnetization and other physical properties of Ce2T3X5 compounds (T=Pd, Rh and Cu; X=Si and A1)　　　　　　　　　　　　　　　
  Yasuyuki Ishii; Masashi Kosaka; Hideki Abe; Hideaki Kitazawa; Giyuu Kido; Yoshiya Uwatoko
  Journal of Magnetism and Magnetic Materials, Volume：277, Number：1-2, First page：60, Last page：63, Jun. 2004, [Reviewed]
  We have synthesized the new ternary compounds Ce2Pd 3Si5, Ce2Cu3Si5 and Ce2Rh3A15 that have the orthorhombic U 2Co3Si5-type of structure. Measurements of the magnetization and other physical properties have been performed on Ce 2T3X5 compounds up to 30 T at 1.5 K and in the temperature range from 2.0 to 300 K. Ce2Pd3Si5 and Ce2Cu3Si5 undergo a transition to the antiferromagnetic state at TN = 7.8 and 4.4 K, respectively. On the other hand, in Ce2Rh3A15 no magnetic transition occurs down to 1.8 K. The highest magnetization values per Ce atom of Ce 2Pd3Si5, Ce2Cu3Si 5 and Ce2Rh3A15 are 0.96, 0.92 and 0.50μB at B = 30 T, respectively. © 2003 Published by Elsevier B.V.
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/j.jmmm.2003.10.007
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  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=2442503346&origin=inward
  DOI ID：10.1016/j.jmmm.2003.10.007, ISSN：0304-8853, SCOPUS ID：2442503346
• Uniaxial-Pressure Induced Ferromagnetism of Enhanced Paramagnetic Sr3Ru2O7　　　　　　　　　　　　　　　
  Shin-Ichi Ikeda; Naoki Shirakawa; Takashi Yanagisawa; Yoshiyuki Yoshida; Shigeru Koikegami; Soh Koike; Masashi Kosaka; Yoshiya Uwatoko
  Journal of the Physical Society of Japan, Volume：73, Number：5, First page：1322, Last page：1325, May 2004, [Reviewed]
  We report a uniaxial pressure-dependence of magnetism in layered perovskite strontium ruthenate Sr3Ru2O7. By applying a relatively small uniaxial pressure, greater than 0.1 GPa normal to the RuO2 layer, ferromagnetic ordering manifests below 80 K from the enhanced-paramagnet. Magnetization at 1 kOe and 2 K becomes 100 times larger than that under ambient condition. Uniaxial pressure dependence of Curie temperature $T_{\text{C } }$ suggests the first order magnetic transition. Origin of this uniaxial-pressure induced ferromagnetism is discussed in terms of the rotation of RuO6 octahedra within the RuO2 plane.
  Physical Society of Japan, English, Scientific journal
  DOI：https://doi.org/10.1143/jpsj.73.1322
  DOI ID：10.1143/jpsj.73.1322, ISSN：0031-9015, eISSN：1347-4073, CiNii Articles ID：110001954850, CiNii Books ID：AA00704814
• Magnetization of single crystalline strontium ruthenate under uniaxial-pressure　　　　　　　　　　　　　　　
  S.I. Ikeda; S. Koiwai; Y. Yoshida; N. Shirakawa; S. Hara; M. Kosaka; Y. Uwatoko
  Journal of Magnetism and Magnetic Materials, Volume：272-276, Number：SUPPL. 1, First page：E293, Last page：E294, May 2004, [Reviewed]
  In order to extract the intrinsic magnetic correlations in Sr 2RuO4, we have performed magnetization measurements under uniaxial pressures (p<0.4GPa) normal to the two-dimensional RuO2 plane. The single crystalline sample grown by a floating-zone method has been used. The results indicate that the magnetization remains paramagnetic up to the maximum pressure without showing any sign of substantial magnetic transitions. Larger pressure is probably necessary to induce ferromagnetic or antiferromagnetic ordering associated with the nature of superconductivity. © 2003 Elsevier B.V. All rights reserved.
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/j.jmmm.2003.12.1027
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  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=23244446621&origin=inward
  DOI ID：10.1016/j.jmmm.2003.12.1027, ISSN：0304-8853, SCOPUS ID：23244446621
• Magnetism in single crystal Ce2Fe17 with two types of magnetic ground states　　　　　　　　　　　　　　　
  Y Makihara; Y Uwatoko; H Matsuoka; M Kosaka; H Fukuda; H Fujii
  Journal of Magnetism and Magnetic Materials, Volume：272-276, Number：I, First page：551, Last page：552, May 2004, [Reviewed]
  Magnetization and neutron diffraction measurements have been performed on two Ce2Fe17 single crystals that have different magnetic ground states. Two types of magnetic structure in the ground states for Ce 2Fe17 are confirmed. From the above results, it is deduced that the hybridization between the Fe 3d- and Ce 4f-electrons plays an important role on the magnetism of Ce2Fe17 in the ground states. © 2004 Elsevier B.V. All rights reserved.
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/j.jmmm.2003.11.197
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=10844281689&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=10844281689&origin=inward
  DOI ID：10.1016/j.jmmm.2003.11.197, ISSN：0304-8853, SCOPUS ID：10844281689
• Ferromagnetism induced in UCoAl under uniaxial pressure　　　　　　　　　　　　　　　
  Y. Ishii; M. Kosaka; Y. Uwatoko; A.V. Andreev; V. Sechovský
  Physica B: Condensed Matter, Volume：334, Number：1-2, First page：160, Last page：166, Jun. 2003, [Reviewed]
  We present the temperature and magnetic-field dependencies of the c-axis magnetization of a UCoAl single crystal under various uniaxial pressures exerted along the c-axis. The main result obtained is the uniaxial-pressure-induced reduction of the critical field of the metamagnetic transition followed by the formation of ferromagnetism at higher uniaxial-pressures. These and other associated results are discussed in comparison with corresponding data obtained by applying hydrostatic pressure on the same material. A scenario considering a variation of the anisotropic 5f-ligand hybridization and its consequences induced by the two different types of applied pressure is an important base for the discussion. The pressure-induced variations of the 5f-3d hybridization within the basal plane of the ZrNiAl-type hexagonal structure seem to be the underlying aspect of the evolution of the magnetism in UCoAl. © 2003 Elsevier Science B.V. All rights reserved.
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/s0921-4526(03)00041-3
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  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=0037568283&origin=inward
  DOI ID：10.1016/s0921-4526(03)00041-3, ISSN：0921-4526, SCOPUS ID：0037568283
• The H-T phase diagrams of CeGa under high pressure for H||a-axis and H||c-axis　　　　　　　　　　　　　　　
  S. Koiwai; M. Kosaka; N. Mori
  Physica B: Condensed Matter, Volume：329-333, First page：643, Last page：644, May 2003, [Reviewed]
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/s0921-4526(02)02553-x
  DOI ID：10.1016/s0921-4526(02)02553-x, ISSN：0921-4526
• Magnetic Properties of Ce2Sc3Ge4Single Crystal　　　　　　　　　　　　　　　
  Masaki Yokoyama; Masashi Kosaka; Nobuo Mōri; Yoshiya Uwatoko; Hideki Abe; Hideaki Kitazawa; Giyuu Kido
  Journal of the Physical Society of Japan, Volume：72, Number：4, First page：947, Last page：950, Apr. 2003, [Reviewed]
  The magnetic properties of a single-crystalline sample Ce2Sc3Ge4 have been investigated, for the first time. On the basis of the magnetization, magnetic susceptibility, electrical resistivity and specific heat measurements, we suggest that Ce2Sc3Ge4 is an antiferromagnetic Kondo compound with $T_{\text{N } } = 5.0$ K. The saturated magnetic moment for the Ce atom is estimated to be 1.1$\mu_{\text{B } }$ at $T = 1.5$ K by the magnetization measurements. Electronic specific heat coefficient $\gamma$ is estimated to be 49.5 mJ/molK2, indicating that the system is described as a medium-heavy fermion compound.
  Physical Society of Japan, English, Scientific journal
  DOI：https://doi.org/10.1143/jpsj.72.947
  DOI ID：10.1143/jpsj.72.947, ISSN：0031-9015, eISSN：1347-4073, CiNii Articles ID：110001954465, CiNii Books ID：AA00704814
• Material properties of Ni Cr Al alloy and design of a 4 GPa class non-magnetic high-pressure cell
  Yoshiya Uwatoko; Sakae Todo; Kazuhiro Ueda; Ahimusa Uchida; Masashi Kosaka; Nobuo Mori; Takehiko Matsumoto
  Journal of Physics: Condensed Matter, Volume：14, Number：44, First page：11291, Last page：11296, Nov. 2002, [Reviewed]
  The Ni-Cr-Al Russian alloy was prepared. Its magnetic and mechanical properties were better than those of MP35N alloy. We fabricated the a piston-cylinder-type hybrid high-pressure cell using the Ni-Cr-Al alloy. It has been found that the maximum working pressure can be repeatedly raised to 3.5 GPa at T = 2 K without any difficulties.
  IOP Publishing, Scientific journal
  DOI：https://doi.org/10.1088/0953-8984/14/44/469
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  DOI ID：10.1088/0953-8984/14/44/469, ISSN：0953-8984, SCOPUS ID：0037064946
• Magnetic properties of Ce3PbC　　　　　　　　　　　　　　　
  M. Kosaka; S. Koiwai; Y. Uwatoko; N. Môri; H. Onodera; K. Ohoyama; H. Abe; H. Kitazawa; G. Kido; T. Kamiyama; H. Noda; T. Omura
  Physica B: Condensed Matter, Volume：312-313, First page：237, Last page：238, Mar. 2002, [Reviewed]
  Ternary compound Ce3PbC has a simple face-centered cubic CaTiO3-type structure. We found that Ce3PbC undergoes a transition to an antiferromagnetic state at TN = 8.4 K and shows an another transition at Tt = 5.8 K. Magnetization process exhibits multi-step metamagnetic transitions at T = 1.5 K. The observation of inelastic neutron experiments suggest that the crystalline electric field (CEF) ground state can be consider to be a doublet. This results imply that the Ce sites are influenced by tetragonal CEF interaction, even though the crystal structure is cubic. We expect that such CEF configuration plays an important role in the behavior of multi-step metamagnetic transitions. © 2002 Elsevier Science B.V. All rights reserved.
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/s0921-4526(01)01094-8
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  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=0036503325&origin=inward
  DOI ID：10.1016/s0921-4526(01)01094-8, ISSN：0921-4526, SCOPUS ID：0036503325
• Magnetic properties of Ce2Sc3Ge4 single crystal　　　　　　　　　　　　　　　
  Masaki Yokoyama; Masashi Kosaka; Nobuo Mori; Yoshiya Uwatoko; Hideki Abe; Hideaki Kitazawa; Giyuu Kido
  Physica B: Condensed Matter, Volume：312-313, First page：269, Last page：270, Mar. 2002, [Reviewed]
  The magnetic properties of Ce2Sc3Ge4 single crystalline sample were investigated. The magnetization, magnetic susceptibility and electrical resistivity were measured. We found that Ce2Sc3Ge4 was an antiferromagnetic Kondo compound with TN = 4.6 K. © 2002 Elsevier Science B.V. All rights reserved.
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/s0921-4526(01)01109-7
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  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=0036503721&origin=inward
  DOI ID：10.1016/s0921-4526(01)01109-7, ISSN：0921-4526, SCOPUS ID：0036503721
• Field-induced non-Fermi liquid behavior of CeGa single crystal　　　　　　　　　　　　　　　
  S. Koiwai; E. Matsuoka; M. Kosaka; Y. Uwatoko
  Physica B: Condensed Matter, Volume：312-313, First page：478, Last page：479, Mar. 2002, [Reviewed]
  We measured the specific heat capacity of single-crystal CeGa in the temperature range 2.0 K≤T≤300 K and under magnetic fields up to H=9 T. A λ-type anomaly is observed at TN=6 K. The electronic specific heat coefficient γ was determined to be 139 mJ/mol K2. With increasing magnetic field, TN) decreases and vanishes at H∼7 T, completely. When TN is just suppressed, i.e., TN→0 K, C/T shows indication of a -log T dependence. © 2002 Elsevier Science B.V. All rights reserved.
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/s0921-4526(01)01545-9
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  DOI ID：10.1016/s0921-4526(01)01545-9, ISSN：0921-4526, SCOPUS ID：0036504210
• Evidence of the anisotropically developed antiferromagnetic spin fluctuation in CeFe2 under high pressures　　　　　　　　　　　　　　　
  T. Fujiwara; H. Fujii; Y. Ishii; S. Koiwai; M. Kosaka; Y. Uwatoko; M. Nishi; K. Kakurai
  Physica B: Condensed Matter, Volume：312-313, First page：336, Last page：338, Mar. 2002, [Reviewed]
  The magnetization measurement of single-crystal CeFe2 under hydrostatic pressures up to 8 kbar indicates that the magnetization is quite anisotropically suppressed at 5 K even in the cubic symmetry by applying the hydrostatic pressure, while the neutron diffraction studies indicate that the static Fe magnetic moment is suppressed to be only half of that under P = 1 bar at 5 K and the antiferromagnetic spin fluctuation with a propagation vector q=(1/2, 1/2, 1/2) is enhanced by applying hydrostatic pressure of 15 kbar. © 2002 Elsevier Science B.V. All rights reserved.
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/s0921-4526(01)01339-4
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  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=0036503494&origin=inward
  DOI ID：10.1016/s0921-4526(01)01339-4, ISSN：0921-4526, SCOPUS ID：0036503494
• Thermal properties of single crystals of CeZn1-xCux　　　　　　　　　　　　　　　
  Yasuyuki Ishii; Shinichi Ohshima; Masashi Kosaka; Yoshiya Uwatoko
  Physica B: Condensed Matter, Volume：312-313, First page：267, Last page：268, Mar. 2002, [Reviewed]
  CeZn1-xCux for x≤0.6 have a cubic CsCl-type structure at ambient condition and exhibits structural phase transitions accompanied with magnetic ordering at low temperature. This time we carried out specific heat capacity measurements on single crystals of CeZn1-xCux for x = 0.2, 0.4 and 0.6. It was found that the ground level of 4f configuration of Ce was changed from quartet for x = 0.2 to doublet for x = 0.6 by Cu substitutions. © 2002 Elsevier Science B.V. All rights reserved.
  English, International conference proceedings
  DOI：https://doi.org/10.1016/S0921-4526(01)01108-5
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  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=0036504182&origin=inward
  DOI ID：10.1016/S0921-4526(01)01108-5, ISSN：0921-4526, SCOPUS ID：0036504182
• Effect of pressure on the electrical resistivity of a single crystal of YbInCu4　　　　　　　　　　　　　　　
  Ahimusa Uchida; Masashi Kosaka; Nobuo Mori; Takehiko Matsumoto; Yoshiya Uwatoko; John L. Sarrao; Joe D. Thompson
  Physica B: Condensed Matter, Volume：312-313, First page：339, Last page：340, Mar. 2002, [Reviewed]
  Temperature-dependent electrical resistivity measurements have been performed on single-crystalline YbInCu4 under hydrostatic pressures to P = 3.3 GPa. Its valence phase-transition temperature TV decreases linearly at a rate of -2.0 K/GPa with increasing pressure to 1.0 GPa, as found previously. Above 1.0 GPA, however, TV decreases more gradually and is depressed to below 1.5 K at 2.5 GPa. Experimental results suggest that the hybridization between 4f- and conduction-band electrons is reduced with increasing pressure and that the semi-metallic state (T >
  TV) is favored over the metallic state (T <
  TV) at high pressures. © 2002 Elsevier Science B.V. All rights reserved.
  English, International conference proceedings
  DOI：https://doi.org/10.1016/S0921-4526(01)01303-5
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  DOI ID：10.1016/S0921-4526(01)01303-5, ISSN：0921-4526, SCOPUS ID：0036503851
• Ferromagnetism Induced in UCoAl by Uniaxial Pressure
  V. Sechovský; A.V. Andreev; Y. Ishii; M. Kosaka; Y. Uwatoko
  High Pressure Research, Volume：22, Number：1, First page：155, Last page：158, Jan. 2002, [Reviewed]
  UCoAl exhibits attributes of an itinerant 5f-electron metamagnet. It is paramagnetic down to lowest temperatures but the c-axis susceptibility shows a maximum around Tmax ≈ 20 K. When a field larger than Bc ≈ 0.6 T is applied along the c-axis of hexagonal structure a ferromagnetic ordering of U moments is induced at low temperatures. The critical parameters Tmax and Bc are sensitive to alloying and hydrostatic pressure. In the latter case values of both, Tmax and Bc, are increasing with increasing pressure, i.e. metamagnetism is suppressed towards a conventional paramagnetism. We report on results of an experiment with a c-axis uniaxial pressure, which has an opposite influence on Tmax and Bc leading to ferromagnetism in zero field. A scenario of the physics of UCoAl is presented accounting for effects of hydrostatic- and uniaxial-pressure on the lattice and consequences in the 5f-electron delocalization and anisotropy of hybridization-mediated exchange interactions.
  Informa UK Limited, Scientific journal
  DOI：https://doi.org/10.1080/08957950211355
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=0012136262&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=0012136262&origin=inward
  DOI ID：10.1080/08957950211355, ISSN：0895-7959, eISSN：1477-2299, SCOPUS ID：0012136262
• Crossbreeding between Experiment and Theory on Orthogonal Dimer Spin System　　　　　　　　　　　　　　　
  Hiroshi Kageyama; Yutaka Ueda; Yasuo Narumi; Koichi Kindo; Masashi Kosaka; Yoshiya Uwatoko
  Progress of Theoretical Physics Supplement, Volume：145, Number：145, First page：17, Last page：22, 2002, [Reviewed]
  We have investigated two-dimensional spin systems SrCu_2(BO_3)_2 and Nd_2BaZnO_5, both of which have a unique topology that is equivalent to the Shastry-Sutherland lattice. The magnetization curve of SrCu_2(BO_3)_2 reveals that, unlike 1/8 and 1/4 plateaux, a 1/3 plateau is very stable, surviving at least up to 69 T. The pressure dependence of susceptibility up to 10 kbar indicates that the pressure causes the system to approach the critical point to some other states. On the other hand, Nd_2BaZnO_5 with rather classical spins exhibits an antiferromagnetic long range ordering at 2.4 K. Finally, other experimental candidates of extended Shastry-Sutherland system will be briefly presented.
  Oxford University Press (OUP), English, Scientific journal
  DOI：https://doi.org/10.1143/ptps.145.17
  DOI ID：10.1143/ptps.145.17, ISSN：0375-9687, CiNii Articles ID：110001209218, CiNii Books ID：AA00791466
• Anomalous Magnetic Susceptibility of Antiferromagnetic TbB2C2　　　　　　　　　　　　　　　
  Koji Kaneko; Hideya Onodera; Masashi Kosaka; Hiroki Yamauchi; Yasuo Yamaguchi
  JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Volume：71, First page：77, Last page：79, Jan. 2002, [Reviewed]
  We measured the magnetic susceptibilities of TbB2C2 under fields along the < 100 >, < 110 > and < 001 > directions. The susceptibilities below T-N exhibit clear twofold symmetry in the < 001 > plane. No spontaneous magnetization in TbB2C2 indicates that this anisotropy in the tetragonal basal plane reflects parallel and perpendicular susceptibilities of an antiferromagnet. The susceptibilities of the < 100 > and [110] directions show- no cusp-like anomaly but anomalous upturns below TN with decreasing temperature, though TbB2C2 is confirmed to be an antiferromagnet,
  PHYSICAL SOC JAPAN, English, Scientific journal
  ISSN：0031-9015, Web of Science ID：WOS:000219953200017
• Dielectric and Magnetic Properties of α′-NaV2O5under Multi-Extreme Conditions　　　　　　　　　　　　　　　
  Yoshiaki Sekine; Nao Takeshita; Nobuo Môri; Masahiko Isobe; Yutaka Ueda; Masashi Kosaka; Yoshiya Uwatoko
  Journal of the Physical Society of Japan, Volume：70, Number：12, First page：3660, Last page：3666, Dec. 2001, [Reviewed]
  We developed a method of precise measurement of the dielectric constant under multi-extreme conditions, that is, under high pressures, high magnetic fields and low temperatures. We measured the dielectric constants and the magnetic susceptibility of single crystals of α′-NaV2O5 under multi-extreme conditions. Anisotropic behavior of a relative dielectric constant was observed at the charge-ordering transition temperature under ambient pressure. With increasing hydrostatic pressure, the transition temperature decreased and another transition appeared below the first transition temperature. The susceptibility exhibited a sharp drop corresponding to the transition to the spin singlet state at the first transition temperature, while it showed no anomaly at the second transition temperature. These two transition temperatures were found to exhibit very weak magnetic field dependence in comparison with typical spin-Peierls compounds.
  Physical Society of Japan, English, Scientific journal
  DOI：https://doi.org/10.1143/jpsj.70.3660
  DOI ID：10.1143/jpsj.70.3660, ISSN：0031-9015, eISSN：1347-4073, CiNii Articles ID：10009124785, CiNii Books ID：AA00704814
• The pressure dependence of magnetization of layered perovskite oxides with 4d-electron metal　　　　　　　　　　　　　　　
  Shin-Ichi Ikeda; Naoki Shirakawa; Sadayoshi Koiwai; Ahimusa Uchida; Masashi Kosaka; Yoshiya Uwatoko
  Physica C: Superconductivity and its Applications, Volume：364-365, First page：376, Last page：378, Nov. 2001, [Reviewed]
  Magnetization measurements for the spin-triplet superconductor Sr2RuO4 under uniaxial pressure and for its relative compound Sr3Ru2O7 under both hydrostatic and uniaxial pressures have been performed from 2 to 300 K. Those samples are single crystals grown by a floating-zone method. Uniaxial pressure normal to the two-dimensional RuO2 plane up to 0.4 GPa has not shown a dramatic effect on the magnetism of single crystalline Sr2RuO4. Magnetization of single crystalline Sr3Ru2O7 under hydrostatic pressure up to 1.4 GPa has indicated that there is no ferromagnetic ordering around 70 K which was observed in our previous work. To clarify these different results, magnetization measurements under uniaxial pressure normal to the RuO2 plane for single crystals of Sr3Ru2O7 is also provided. The results imply that the uniaxial component is essential for the appearance of ferromagnetism. © 2001 Elsevier Science B.V. All rights reserved.
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/s0921-4534(01)00800-0
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=0035499428&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=0035499428&origin=inward
  DOI ID：10.1016/s0921-4534(01)00800-0, ISSN：0921-4534, SCOPUS ID：0035499428
• Near the collapse of ferromagnetism in CeFe2 under high pressures　　　　　　　　　　　　　　　
  H Fukuda; H Fujii; H Kamura; A Uchida; M Kosaka; Y Uwatoko
  Journal of Magnetism and Magnetic Materials, Volume：226-230, Number：PART II, First page：1200, Last page：1202, May 2001, [Reviewed]
  The magnetization of single crystalline CeFe2 was measured in the temperature range from 2 to 300 K under hydrostatic pressures up to 8 k bar. The magnetization at 5 K along the each principal axis in CeFe2 was quite anisotropically suppressed even in the cubic symmetry by applying hydrostatic pressure, that was mostly pronounced along the [111] axis. Such an anisotropic suppression of magnetization might occur as a result of an anisotropic suppression of the antiferromagnetic spin fluctuations due to magnetic field coming from the anisotropic Ce 4f-Fe 3d hybridizations with strong magnetoelastic effect © 2001 Elsevier Science B.V. All rights reserved.
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/s0304-8853(00)00736-8
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=0035327889&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=0035327889&origin=inward
  DOI ID：10.1016/s0304-8853(00)00736-8, ISSN：0304-8853, SCOPUS ID：0035327889
• Interplay between non-magnetic dilution and pressure effects in magnetism of UCoAl　　　　　　　　　　　　　　　
  A.V Andreev; M Kosaka; Y Uwatoko; V Sechovskỳ; Y Homma; Y Shiokawa
  Journal of Magnetism and Magnetic Materials, Volume：226-230, Number：PART I, First page：967, Last page：969, May 2001, [Reviewed]
  Effects of external hydrostatic pressure and Y(Lu) substitutions for U on magnetism, in U1-xY(Lu)xCoAl compounds were studied. Y and Lu doping of UCoAl leads to a gradual development of ferromagnetism in a limited concentration range. Reentrant metamagnetism of the UcoAl type is observed in the ferromagnetic U1-x,Y(Lu)x,CoAl compounds after application of a sufficient external pressure. © 2001 Elsevier Science B.V. All rights reserved.
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/s0304-8853(00)01161-6
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=34250181829&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=34250181829&origin=inward
  DOI ID：10.1016/s0304-8853(00)01161-6, ISSN：0304-8853, SCOPUS ID：34250181829
• Magnetization of Eu0.58Sr0.42MnO3 under High Pressure.　　　　　　　　　　　　　　　
  T. Eto; G. Oomi; E. V. Sampathkumaran; A. Sundaresan; M. Kosaka; Y. Uwatoko
  Journal of the Magnetics Society of Japan, Volume：25, Number：4-2, First page：723, Last page：726, 2001, [Reviewed]
  Magnetization of Eu_0.58Sr_0.42MnO₃ was measured under hydrostatic pressures up to 0.8 GPa in order to investigate the effect of pressure on the metal-insulator transition, which was investigated at high pressure by resistivity measurements. At ambient pressure, below about 45 K, the magnetization vs temperature curve reveals a spin-glass behavior as reported for a previous experiment. With increasing pressure, the magnetization increases at both 0.005 T and 0.5 T, and a cluster-glass behavior appears at 0.5 T above 0.37 GPa. On the other hand, the magnetization increases with increasing pressure at 1.5 T and 5.0 T. We also found that the high-field susceptibility increases linearly with increasing pressure at a rate of (dχ_hf/dp) = 0.0336(6)μ_BT^-1 GPa^-1.
  The Magnetics Society of Japan, English, Scientific journal
  DOI：https://doi.org/10.3379/jmsjmag.25.723
  DOI ID：10.3379/jmsjmag.25.723, ISSN：0285-0192, CiNii Articles ID：110002811049, CiNii Books ID：AN0031390X, ORCID：95560466
• Magnetic properties of R7Rh3 (R=Tb, Dy and Ho) in high magnetic fields　　　　　　　　　　　　　　　
  T. Tsutaoka; T. Tokunaga; M. Kosaka; Y. Uwatoko; H. Suzuki; H. Kitazawa; G. Kido
  Physica B: Condensed Matter, Volume：294-295, First page：199, Last page：202, Jan. 2001, [Reviewed]
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/s0921-4526(00)00643-8
  DOI ID：10.1016/s0921-4526(00)00643-8, ISSN：0921-4526
• Effect of pressure on the magnetostriction and the magnetization of Eu0.58Sr0.42MnO3　　　　　　　　　　　　　　　
  T. Eto; G. Oomi; E. V. Sampathkumaran; A. Sundaresan; M. Kosaka; Y. Uwatoko
  Physica B: Condensed Matter, Volume：294-295, Number：4, First page：111, Last page：114, Jan. 2001, [Reviewed]
  Magnetostriction and magnetization of Eu0.58Sr0.42MnO3 were measured under hydrostatic pressures up to 2.0 GPa in order to investigate the effect of pressure on the metal-insulator (M-I) transition, recently investigated by resistivity measurements. At ambient pressure, around 2 T and 6 K, where the field-induced M-I transition was previously reported, the observed magnetostriction was estimated to be 0.04%. With increasing pressure, the saturation magnetization increased at a field of 0.5 T, whereas it decreased at fields of 1.5 and 5.0 T.
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/s0921-4526(00)00620-7
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=0035059447&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=0035059447&origin=inward
  DOI ID：10.1016/s0921-4526(00)00620-7, ISSN：0921-4526, SCOPUS ID：0035059447
• Ground state in Sr3Ru2O7: Fermi liquid close to a ferromagnetic instability　　　　　　　　　　　　　　　
  S Ikeda; Y Maeno; S Nakatsuji; M Kosaka; Y Uwatoko
  PHYSICAL REVIEW B, Volume：62, Number：10, First page：R6089, Last page：R6092, Sep. 2000, [Reviewed]
  We show that single-crystalline Sr3Ru2O7 grown by a floating-zone technique is an isotropic paramagnet and a quasi-two-dimensional metal, as spin-tripler superconducting Sr2RuO4 is. The ground state is a Fermi liquid with very low residual resistivity (approximate to 3 mu Omega cm for in-plane currents) and a nearly ferromagnetic metal with the largest Wilson ratio R(W)greater than or equal to 10 among paramagnets so far. This contrasts with the ferromagnetic order at T-c = 104 K reported on single crystals grown by a flux method [Cao et al., Phys. Rev. B 55, R672 (1997)]. However, we have found a dramatic changeover from paramagnetism to ferromagnetism under applied pressure. This suggests the existence of a substantial ferromagnetic instability in the Fermi-liquid state.
  AMER PHYSICAL SOC, English, Scientific journal
  ISSN：1098-0121, eISSN：1550-235X, Web of Science ID：WOS:000089304400010
• Pressure effects on magnetism in U1−xYxCoAl compounds　　　　　　　　　　　　　　　
  A.V Andreev; M Kosaka; Y Uwatoko; V Sechovský
  Journal of Alloys and Compounds, Volume：309, Number：1-2, First page：45, Last page：50, Sep. 2000, [Reviewed]
  We report on the magnetization study of moderately Y substituted U1-xYxCoAl compounds under ambient and high pressures. The Y (as well as Lu and Th) substitutions for U in UCoAl lead to the onset of ferromagnetism for a limited Y concentration range. Application of pressure drives these ferromagnets back to the itinerant electron metamagnetism of UCoAl-type. The results are discussed in the context of the expected pressure influence on the electronic structure.
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/s0925-8388(00)01070-7
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=0034276347&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=0034276347&origin=inward
  DOI ID：10.1016/s0925-8388(00)01070-7, ISSN：0925-8388, SCOPUS ID：0034276347
• Ground state in Sr3Ru2O7: Fermi liquid close to a ferromagnetic instability
  Shin Ichi Ikeda; Shin Ichi Ikeda; Yoshiteru Maeno; Yoshiteru Maeno; Satoru Nakatsuji; Masashi Kosaka; Yoshiya Uwatoko
  Physical Review B - Condensed Matter and Materials Physics, Volume：62, Number：10, First page：R6089, Last page：R6092, Sep. 2000, [Reviewed]
  We show that single-crystalline Sr 3 Ru 2 O 7 grown by a floating-zone technique is an isotropic paramagnet and a quasi-two-dimensional metal, as spin-triplet superconducting Sr 2 RuO 4 is. The ground state is a Fermi liquid with very low residual resistivity (≈-3 μΩ cm for in-plane currents) and a nearly ferromagnetic metal with the largest Wilson ratio R w ≥ 10 among paramagnets so far. This contrasts with the ferromagnetic order at T c = 104 K reported on single crystals grown by a flux method [Cao et al., Phys. Rev. B 55, R672 (1997)]. However, we have found a dramatic changeover from paramagnetism to ferromagnetism under applied pressure. This suggests the existence of a substantial ferromagnetic instability in the Fermi-liquid state.
  Scientific journal
  DOI：https://doi.org/10.1103/PhysRevB.62.R6089
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=0034261397&origin=inward
  DOI ID：10.1103/PhysRevB.62.R6089, ISSN：0163-1829, SCOPUS ID：0034261397
• Specific heat and effect of pressure on the electrical resistivity of CePtGa single crystal　　　　　　　　　　　　　　　
  Yoshiya Uwatoko; Masashi Kosaka; Makoto Shirakawa; Gendo Oomi; Nobuo Môri; Tatsuo Kobayashi; Hiroshi Tatewaki; Katsuya Shimizu; Kiichi Amaya
  Physica B: Condensed Matter, Volume：284-288, Number：PART II, First page：1321, Last page：1322, Jul. 2000, [Reviewed]
  Specific heat and effect of pressure on the electrical resistivity of CePtGa single crystal have been measured upto 30 kbar. A sharp peak in the ratio of specific heat to temperature and in electrical resistivity is observed at 3.3 and 3.5 K, respectively, which is ascribed to an antiferromagnetic transition. The results reveal that TN decreases linearly with increasing pressure upto 30 kbar. © 2000 Elsevier Science B.V. All rights reserved.
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/s0921-4526(99)02593-4
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=2442453936&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=2442453936&origin=inward
  DOI ID：10.1016/s0921-4526(99)02593-4, ISSN：0921-4526, SCOPUS ID：2442453936
• Effect of pressure on the electrical resistivity of Ce3SnC single crystal　　　　　　　　　　　　　　　
  Masashi Kosaka; Toshiaki Seino; Yoshiya Uwatoko; Hideya Onodera; Nao Takeshita; Nobuo Môri
  Physica B: Condensed Matter, Volume：284-288, Number：PART II, First page：1323, Last page：1324, Jul. 2000, [Reviewed]
  New ternary compound Ce3SnC has a simple face-centered cubic CaO3 Ti-type structure. We found that Ce3SnC undergoes a transition to an antiferromagnetic state at TN = 7.0 K and the magnetization process shows multi-step metamagnetic transitions at T = 1.5 K. In this work, we present the effect of pressure on the electrical resistivity of Ce3SnC. The anomaly which originates from antiferromagnetic ordering is observed around TN at 1 bar. The results reveal that TN increases drastically with increasing pressure up to P = 23 kbar. © 2000 Elsevier Science B.V. All rights reserved.
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/s0921-4526(99)02595-8
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=4243813876&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=4243813876&origin=inward
  DOI ID：10.1016/s0921-4526(99)02595-8, ISSN：0921-4526, SCOPUS ID：4243813876
• Magnetic properties of new ternary-compounds Ce2Sc3M4 (M=Si, Ge)　　　　　　　　　　　　　　　
  M Yokoyama; M Kosaka; Y Uwatoko
  Physica B: Condensed Matter, Volume：281-282, First page：112, Last page：113, Jun. 2000, [Reviewed]
  The Ce2Sc3M4 (M = Si and Ge) polycrystalline compounds were synthesized. Ce2Sc3Si4 and Ce2Sc3Ge4 were investigated by measuring the magnetization and electrical resistivity. The complex magnetic behavior was shown at low temperature for both compounds.
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/s0921-4526(99)00937-0
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=0033884568&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=0033884568&origin=inward
  DOI ID：10.1016/s0921-4526(99)00937-0, ISSN：0921-4526, SCOPUS ID：0033884568
• Magneitc instability of CeScGe　　　　　　　　　　　　　　　
  T Shigeoka; M Yokoyama; M Kosaka; Y Uwatoko; M Furugen; S Ishida; S Asano
  Physica B: Condensed Matter, Volume：281-282, First page：96, Last page：97, Jun. 2000, [Reviewed]
  The magnetic instability of CeScGe is investigated from single crystal magnetization and calculation of electronic structures by LMTO method. A ferromgnetic groud state is concluded in this compound. © 2000 Elsevier Science B.V. All rights reserved.
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/s0921-4526(99)00939-4
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=0033894044&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=0033894044&origin=inward
  DOI ID：10.1016/s0921-4526(99)00939-4, ISSN：0921-4526, SCOPUS ID：0033894044
• Effect of pressure on the antiferro-quadrupolar transition of CeB6　　　　　　　　　　　　　　　
  Y Uwatoko; M Kosaka; M Sera; S Kunii
  Physica B: Condensed Matter, Volume：281-282, First page：555, Last page：556, Jun. 2000, [Reviewed]
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/s0921-4526(99)00938-2
  DOI ID：10.1016/s0921-4526(99)00938-2, ISSN：0921-4526
• Effect of pressure on the ferroquadrupolar compound TmAu2　　　　　　　　　　　　　　　
  M Kosaka; Y Uwatoko; T Seino; H Onodera; K Ohoyama; Y Yamaguchi; M Ohashi
  PHYSICA B, Volume：281, First page：593, Last page：594, Jun. 2000, [Reviewed]
  TmAu2 with a simple body-centered tetragonal MoSi2-type structure undergoes an electric transition to a ferroquadrupolar ordered state at T-Q of 7.0 K and a magnetic transition to an antiferomagnetic state at T-N Of 3.2 K, We have measured pressure dependence of electrical resistivity on single-crystalline TmAu2 sample. The results reveal that the T-N decreased with increasing pressure (partial derivative T-N/partial derivative P = - 4.54 mK/kbar), while the T-Q increased with increasing pressure (partial derivative T-Q/partial derivative P = 21.5 mK/kbar). (C) 2000 Elsevier Science B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  ISSN：0921-4526, Web of Science ID：WOS:000086570200246
• Magnetic properties of Ce3TX compounds (T = Al, In, Sn and Pb; X = C and B)　　　　　　　　　　　　　　　
  M Kosaka; Y Uwatoko; T Seino; H Onodera
  PHYSICA B, Volume：281, First page：114, Last page：115, Jun. 2000, [Reviewed]
  We have synthesized new ternary compounds Ce3TX (T = Al, In. Sn and Pb, X = C and B) which have a simple face-centered cubic CaO3 Ti-type structure. Magnetization measurements were performed on Ce3TX compounds up to H = 5 T in the range of T = 2.0-300 K. For Ce3TC, we found antiferromagnetic orderings and metamagnetic transitions. For Ce3TC. anomalies which might be associated with structural phase transition were observed in magnetic susceptibilities. (C) 2000 Elsevier Science B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  ISSN：0921-4526, Web of Science ID：WOS:000086570200047
• Magnetic Properties of Ce_2Sc_3M_4(M=Si, Ge) Single Crystals　　　　　　　　　　　　　　　
  YOKOYAMA Masaki; SHIRO Masanori; TAKESHITA Nao; MORI Nobuo; KOSAKA Masashi; UWATOKO Yoshiya
  Meeting Abstracts of the Physical Society of Japan, Volume：55, Number：0, First page：549, Last page：549, 2000
  The Physical Society of Japan, Japanese
  DOI：https://doi.org/10.11316/jpsgaiyo.55.1.3.0_549_1
  DOI ID：10.11316/jpsgaiyo.55.1.3.0_549_1, CiNii Articles ID：110001913984
• Uniaxial-stress induced magnetic order in CeNiSn　　　　　　　　　　　　　　　
  K. Umeo; T. Igaue; H. Chyono; Y. Echizen; T. Takabatake; M. Kosaka; Y. Uwatoko
  Physical Review B, Volume：60, Number：10, First page：R6957, Last page：R6960, Sep. 1999, [Reviewed]
  We report the observation of an unexpected magnetic transition in the Kondo semimetal CeNiSn under uniaxial pressures. For P∥a, both the specific heat C and magnetic susceptibility χ decrease steadily with increasing P. By contrast, once P∥b and P∥c exceed 0.13 GPa, C(T) exhibits a distinct jump at 4 K followed by a peak at 3 K. The concomitant peaking in χ(T) for P∥B∥c is indicative of an antiferromagnetic transition.
  American Physical Society (APS), English, Scientific journal
  DOI：https://doi.org/10.1103/physrevb.60.r6957
  DOI ID：10.1103/physrevb.60.r6957, ISSN：0163-1829, eISSN：1095-3795, CiNii Articles ID：120000880297, CiNii Books ID：AA11187113
• Magnetic structure modified by the quadrupolar interaction in DyB2C2　　　　　　　　　　　　　　　
  H Yamauchi; H Onodera; M Ohashi; K Ohoyama; T Onimaru; M Kosaka; Y Yamaguchi
  Journal of Physics and Chemistry of Solids, Volume：60, Number：8-9, First page：1217, Last page：1220, Sep. 1999, [Reviewed]
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/s0022-3697(99)00088-8
  DOI ID：10.1016/s0022-3697(99)00088-8, ISSN：0022-3697
• Antiferroquadrupolar ordering and magnetic properties of the tetragonal DyB2C2 compound　　　　　　　　　　　　　　　
  H Yamauchi; H Onodera; K Ohoyama; T Onimaru; M Kosaka; M Ohashi; Y Yamaguchi
  JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Volume：68, Number：6, First page：2057, Last page：2066, Jun. 1999, [Reviewed]
  Magnetic properties were investigated on a single-crystalline DyB2C2 compound with the tetragonal structure. Spontaneous magnetizations appear along the a- and [110]-directions below T-c = 15.3 K. A very small sholder is observed only along the c-axis at T-Q = 24.7 K, although large lambda-type anomalous specific heats are observed at T-C and T-Q. There exists a large magnetic anisotropy in the tetragonal basal plane which is observed in magnetization processes below T-C. Neutron powder diffraction experiments reveal that magnetic reflections are observed only below T-C. In the magnetically ordered phase, the Dy moments are arranged to he perpendicular to neighbours along the c-axis. The results are well interpreted by postulating that the phae between T-C and T-Q is an antiferroquadrupolar ordered one. DyB2C2 is a novel compound with a high antiferrocluadrupolar ordering temperature of 24.7 K.
  PHYSICAL SOCIETY JAPAN, English, Scientific journal
  ISSN：0031-9015, Web of Science ID：WOS:000081097300046
• Magnetic properties of single crystals CeScGe and CeScSi　　　　　　　　　　　　　　　
  Y Uwatoko; M Kosaka; T Sigeoka
  Physica B: Condensed Matter, Volume：259-261, First page：114, Last page：115, Jan. 1999, [Reviewed]
  The magnetization of single crystalline samples of CeScSi and CeScGe was measured in the temperature range from 2.2 to 60 K. We found that the single crystal samples CeScSi and CeScGe have the same values of spontaneous magnetization about μCe = 0.3μB along c-axis at low temperature. © 1999 Elsevier Science B.V. All rights reserved.
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/s0921-4526(98)00968-5
  Scopus：https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=4243322267&origin=inward
  Scopus Citedby：https://www.scopus.com/inward/citedby.uri?partnerID=HzOxMe3b&scp=4243322267&origin=inward
  DOI ID：10.1016/s0921-4526(98)00968-5, ISSN：0921-4526, SCOPUS ID：4243322267
• Magnetic Properties of CeGa Single Crystal　　　　　　　　　　　　　　　
  E. Matsuoka; M. Kosaka; H. Suzuki; H. Kitazawa; G. Kido; Y. Uwatoko
  Quantum Phenomena in Advanced Materials at High Magnetic Fields, First page：185, Last page：187, 1999
  International conference proceedings
• High Field Magnetization of Ce3SnC　　　　　　　　　　　　　　　
  M. Kosaka; Y. Uwatoko; T. Seino; H. Onodera; H. Suzuki; H. Kitazawa; G. Kido
  Quantum Phenomena in Advanced Materials at High Magnetic Fields, First page：181, Last page：183, 1999
  International conference proceedings
• Uniaxial pressure apparatus for magnetization measurements　　　　　　　　　　　　　　　
  Y. Uwatoko; M. Kosaka; T. Oki; K. Umeo; T. Takabatake; N. Mori; G. Oomi
  Science and Technology of High Pressure, Volume：2, First page：1113, Last page：1115, 1999, [Reviewed]
• Effect ofPressure on the Valence Phase Transition in CeNi0.65Co0.35Sn　　　　　　　　　　　　　　　
  M. Kosaka; Y. Uwatoko; D. T. Adroja; T. Takabatake
  Volume：2, First page：747, Last page：748, 1999, [Reviewed]
• Magnetic properties of single-crystalline RNiC2 compounds (R = Ce, Pr, Nd and Sm)　　　　　　　　　　　　　　　
  H Onodera; Y Koshikawa; M Kosaka; M Ohashi; H Yamauchi; Y Yamaguchi
  JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, Volume：182, Number：1-2, First page：161, Last page：171, Feb. 1998, [Reviewed]
  Magnetic properties of CeNiC2, PrNiC2, NdNiC2 and SmNiC2 compounds have been investigated by means of magnetization measurement on the single-crystalline samples. CeNiC2 is a antiferromagnet of T-N = 19.8 K with a moment direction parallel to the a-axis. Two order-order transitions appear at 2.2 and 10.0 K. In a magnetization curve at 1.5 K of a Van Vleck paramagnet PrNiC2, there appear two anomalous increases at 17.5 and 140 kOe. NdNiC2 is also a antiferromagnet of T-N = 17.2 K With a moment of 2.45 mu(B) parallel to the a-axis. There appears an order-order transition at 4.0 K. The magnetic structure is transformed directly into ferromagnetic one by a field of 38 kOe at 4.2 K. SmNiC2 is a novel ferromagnet of T-C = 17.5 K with a moment of 0.32 mu(B) parallel to the a-axis. Besides the ferromagnetic transition is of first order. There appears three anomalous changes in the magnetizations at T-t1 = 4.3 K, T-t2 = 13.0 K and T-t3 = 25.0 K. The susceptibilities around 300 K presumably stand for a valence fluctuation of Sm ions. (C) 1998 Elsevier Science B.V. All rights reserved.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/S0304-8853(97)01011-1
  DOI ID：10.1016/S0304-8853(97)01011-1, ISSN：0304-8853, CiNii Articles ID：80010178705, Web of Science ID：WOS:000072320800021
• Quadrupolar ordering and magnetic properties of tetragonal TmAu2　　　　　　　　　　　　　　　
  M. Kosaka; H. Onodera; K. Ohoyama; M. Ohashi; Y. Yamaguchi; S. Nakamura; T. Goto; H. Kobayashi; S. Ikeda
  Volume：58, Number：10, First page：6339, Last page：6345, 1998, [Reviewed]
  DOI：https://doi.org/10.1103/PhysRevB.58.6339
  DOI ID：10.1103/PhysRevB.58.6339, ISSN：0163-1829, CiNii Articles ID：120000775763
• TOF neutron powder diffraction studies on f-electron systems　　　　　　　　　　　　　　　
  T Kamiyama; K Oikawa; F Izumi; M Kosaka; H Onodera; Y Yamaguchi; M Kasaya; K Kojima
  Physica B: Condensed Matter, Volume：241-243, First page：376, Last page：378, Dec. 1997, [Reviewed]
  Elsevier BV, Scientific journal
  DOI：https://doi.org/10.1016/s0921-4526(97)00593-0
  DOI ID：10.1016/s0921-4526(97)00593-0, ISSN：0921-4526
• Crystalline electric fields and magnetic properties of single-crystalline RNiC2 compounds (R=Ho, Er and Tm)　　　　　　　　　　　　　　　
  Y Koshikawa; H Onodera; M Kosaka; H Yamauchi; M Ohashi; Y Yamaguchi
  JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, Volume：173, Number：1-2, First page：72, Last page：82, Sep. 1997, [Reviewed]
  Magnetometric investigations were performed onsingle-crystalline HoNiC2, ErNiC2 and TmNiC2 compounds. Susceptibility of HoNiC2 shows no anomaly around T-N, but a clear cusp appears at T-t = 2.9 K. Magnetization curves reveal that the anisotropy is relatively weak and that the Ho moments align not along any crystallographic axis. In addition to T-N = 8.5 K of ErNiC2, a new order-order transition at T-t = 3.6 K has been found. Although the Er moments align along the a-axis between T-t and T-N, it seems certain that the small moment-components along the b- and c-axes come into existence below T-t. TmNiC2 with T-N = 5.5 K has a strong uniaxial anisotropy along the a-axis. These results are discussed on the basis of competitions between the magnetic interactions and the crystal held effect which changes anomalously by the replacement of rare earth element. It has been found that the drastic change of crystal field occurs between HoNiC2 and ErNiC2 without any corresponding structural change.
  ELSEVIER SCIENCE BV, English, Scientific journal
  ISSN：0304-8853, Web of Science ID：WOS:A1997YC64700009
• Crystalline electric field and magnetic properties of the TmCu2Si2 intermetallics　　　　　　　　　　　　　　　
  M Kosaka; H Onodera; K Ohoyama; M Ohashi; Y Yamaguchi; S Nakamura; T Goto
  JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN, Volume：66, Number：9, First page：2844, Last page：2850, Sep. 1997, [Reviewed]
  The magnetic properties of TmCu2Si2 are studied by magnetometric measurement, inelastic neutron scattering (INS) experiment, elastic constant measurement using ultrasonic velocity and neutron diffraction experiment on the powdered and single crystalline samples. Crystalline electric field (CEF) parameters which are determined by the magnetic susceptibility and the INS spectrum give 4f CEF levels consisting of a singlet Gamma(3)((1)) ground state, a singlet Gamma(4)((1)) first excited state at 6.1 K, a doublet Gamma(5)((1)) second excited state at 79.5 K, and so on. Temperature variation of the 4f CEF level population, especially that of doublet Gamma(5)((1)), explains well anomalous behavior of the magnetic susceptibility along the a-axis exhibiting the minimum around 15 K and the maximum around 45 K. Weak lattice softening below 120 K is also attributable mainly to strain susceptibility of Gamma(5)((1)). An exchange-induced Van Vleck antiferromagnetic transition occurs at 2.8 K, since magnitude of transition probability between the ground Gamma(3)((1)) and excited Gamma(4)((1)) singlets is so large to induce the magnetic transition. It is confirmed that the antiferromagnetic structure is a sinusoidally moment-modulated one described by a propagation vector of q = (delta, delta, 0) with delta = 0.147, where the Tm moments align along the c-axis.
  PHYSICAL SOC JAPAN, English, Scientific journal
  DOI：https://doi.org/10.1143/JPSJ.66.2844
  DOI ID：10.1143/JPSJ.66.2844, ISSN：0031-9015, CiNii Articles ID：110001970603, Web of Science ID：WOS:A1997XZ76700049
• Dy-161 and Gd-155 Mossbauer spectroscopy of the RTC2 intermetallics (R=Dy, Gd; T=Ni, Co)　　　　　　　　　　　　　　　
  H Onodera; H Amanai; S Matsuo; M Kosaka; H Kobayashi; M Ohashi; Y Yamaguchi
  SCIENCE REPORTS OF THE RESEARCH INSTITUTES TOHOKU UNIVERSITY SERIES A-PHYSICS CHEMISTRY AND METALLURGY, Volume：45, Number：1, First page：1, Last page：10, Mar. 1997, [Reviewed]
  Dy-161 and Gd-155 Mossbauer spectroscopic studies on DyCoC2, DyNiC2, GdCoC2 and GdNiC2 which were performed in order to obtain microscopic information on magnetic properties are reviewed. The experiments were done using the standard Tb-161 and Eu-155 Mossbauer sources prepared by neutron irradiation at the Japan Material Testing Reactor. A simple ferromagnetic DyCoC2 is a good object to compare the magnetic hyperfine field with the magnetic moment determined precisely by the magnetization measurement of the single crystalline sample. DyNiC2 is an antiferromagnet with commensurate magnetic structure and incommesurate moment-modulation structure. The magnetic hyperfine held changes correspondently well with the both magnetic structures. It is exhibited that the Gd-155 Mossbauer spectroscopy is very useful to determine the moment direction in the Gd compounds which are rarely investigated by neutron diffraction because of large neutron absorption cross section of the natural Gd nuclei. The crystalline electric field parameter A(2)(0) determined from the quadrupole interaction acting on Gd is also useful to interpret the magnetic anisotropy of the other rare earth atoms in the isostructural compounds.
  INST MATERIALS RESEARCH LIBRARY, English, Scientific journal
  ISSN：0040-8808, Web of Science ID：WOS:A1997XR93100002
• Performance of a torque magnetometer in high magnetic fields using a hybrid magnet　　　　　　　　　　　　　　　
  M Kosaka; H Onodera; T Nakamichi; Y Yamaguchi
  JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS, Volume：35, Number：12A, First page：6292, Last page：6296, Dec. 1996, [Reviewed]
  Measurements using a torque magnetometer are performed under high magnetic fields generated by a hybrid magnet. It is clarified that rotation angle determination by a double-coil method is advantageous compared with that by a single-coil method. Interference by ripple fields induced by vibration of a water-cooled magnet is eliminated to a sufficient degree through the use of a Cu shield. In the measurement, a sudden jump of the rotation angle occurs in the case of unsaturated magnetization. After the reason is discussed based on simulation of the jump behavior; supplementary measurement by the reverse rotation method is recommended for more favorable data accumulation. Examples of torque measurement for a Co single crystal and a sintered ND2Fe14B sample are provided.
  JAPAN J APPLIED PHYSICS, English, Scientific journal
  DOI：https://doi.org/10.1143/JJAP.35.6292
  DOI ID：10.1143/JJAP.35.6292, ISSN：0021-4922, CiNii Articles ID：110003905539, Web of Science ID：WOS:A1996WF47900071
• Antiferromagnetism of GdCoC2 and GdNiC2 intermetallics studied by magnetization measurement and Gd-155 Mossbauer spectroscopy　　　　　　　　　　　　　　　
  S Matsuo; H Onodera; M Kosaka; H Kobayashi; M Ohashi; H Yamauchi; Y Yamaguchi
  JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, Volume：161, First page：255, Last page：264, Aug. 1996, [Reviewed]
  Magnetic properties of GdCoC2 and GdNiC2 are investigated by means of magnetization measurement of single crystals and Gd-155 Mossbauer spectroscopy of powdered samples. GdCoC2 is an antiferromagnet below T-N = 15.6 K and shows an order-order transition at T-t = 14.0 K. The measurements of Gd-155 Mossbauer effect and magnetization process reveal that the Gd moments align noncollinearly by an angle of 48 degrees from the a-axis in the c plane. GdNiC2 is an antiferromagnet below T-N = 20.0 K. The Gd moments align noncollinearly by angles of 18 degrees from the c-axis and 45 degrees from the a-axis in the c-plane. By the Gd-155 Mossbauer measurements, crystal field parameters are derived to be A(2)(0) = -498 K/a(0)(2) in GdCoC2 and A(2)(0) = 277 K/a(0)(2) in GdNiC2.
  ELSEVIER SCIENCE BV, English, Scientific journal
  DOI：https://doi.org/10.1016/S0304-8853(96)01282-6
  DOI ID：10.1016/S0304-8853(96)01282-6, ISSN：0304-8853, Web of Science ID：WOS:A1996VR56200039
• HIGH-FIELD METAMAGNETIC TRANSITIONS OF NDCO2SI2　　　　　　　　　　　　　　　
  T SHIGEOKA; N IWATA; M EGUCHI; M KOSAKA; H ONODERA
  PHYSICA B, Volume：211, Number：1-4, First page：121, Last page：123, May 1995, [Reviewed]
  High field magnetization of a NdCo2Si2 single crystal has been investigated up to 15 T below T-N = 32 K. A three-step metamagnetic process was observed along the c-axis below T-1 = 15 K. Critical fields in the ascending process are H-c1 = 5.0 T, H-c2 = 6.4 T and H-c3 = 13.3 T, and in the descending process, H-c1 = 2.5 T, H-c2 = 4.5 T and H-c3 = 13.2 T. The magnetic H-T phase diagram along the c-axis has been determined, which can be explained by the self-consistent periodic exchange field model.
  ELSEVIER SCIENCE BV, English, Scientific journal
  ISSN：0921-4526, Web of Science ID：WOS:A1995RD54400028
• Jc Measurements and the Observation of Flux Movements and Flux Jumps in Quench-and-Melt Growth YBCO by a Pulsed Magnetic-Field　　　　　　　　　　　　　　　
  T. Takizawa; M. Kosaka; K. Kanbara; M. Morita; K. Sawano
  Japanese Journal of Applied Physics, Volume：30, Number：10, First page：L1790, Last page：L1793, 1991, [Reviewed]
  An observation of the flux motion in a ring-shaped quench-and-melt growth (QMG) YBCO has been attempted under a pulsed magnetic field in a temperature range from $T_{\text{c } }$ down to 25 K. The transport critical current density ($J_{\text{c } }$) is estimated from the magnetic field where the flux just enters into the central hole of the sample ring. At low temperatures, the flux jump is clearly observed and its interpretation is made in terms of the traditional stabilization theory. In a thin sample, a peculiar flux motion suggesting the undulation of flux lines is observed.
  The Japan Society of Applied Physics, English, Scientific journal
  DOI：https://doi.org/10.1143/JJAP.30.L1790
  DOI ID：10.1143/JJAP.30.L1790, ISSN：0021-4922, CiNii Articles ID：110003923725, CiNii Books ID：AA10650595

• Electronic transport properties of f-electron compound EuZn₂Ge₂　　　　　　　　　　　　　　　
  齋藤一輝; 佐藤択音; 高木壮馬; 中村光輝; 脇舎和平; 吉澤正人; 飯塚亮介; 小坂昌史; 中西良樹
  日本物理学会講演概要集(CD-ROM), Volume：79, Number：1, 2024
  ISSN：2189-079X, J-Global ID：202402289329387489
• Elastic properties investigation of the tetragonal EnZn₂Ge₂ proved by ultrasonic measurements　　　　　　　　　　　　　　　
  齋藤一輝; 佐藤択音; 中村光輝; 脇舎和平; 吉澤正人; 飯塚亮介; 小坂昌史; 中西良樹
  日本物理学会講演概要集(CD-ROM), Volume：78, Number：2, 2023
  ISSN：2189-079X, J-Global ID：202302237350180174
• 7aPS-111 Anomalous temperature dependence in magnetotransport properties in Gd_xY_<1-x>H_2 (x=0.4)　　　　　　　　　　　　　　　
  Sakuraba T.; Kitajima A.; Oshima A.; Hasegawa S.; Nakamura O.; Haruyama S.; Kudo K.; Sakai M.; Honda Z.; Kirigane T.; Numakura R.; Kosaka M.; Higuchi K.
  Meeting Abstracts of the Physical Society of Japan, Volume：69, Number：0, First page：257, Last page：257, 2014
  The Physical Society of Japan, Japanese
  DOI ID：10.11316/jpsgaiyo.69.2.3.0_257_3, ISSN：1342-8349, CiNii Articles ID：110009887121, CiNii Books ID：AA11439205
• 26pED-12 Magnetic Phase Diagram and Structural Modulation of Rare-earth Compound GdNiC_2　　　　　　　　　　　　　　　
  Mikami K.; Hanasaki N.; Yokota K.; Nogami Y.; Shimomura S.; Nakao H.; Kosaka M.; Onodera H.
  Meeting abstracts of the Physical Society of Japan, Volume：66, Number：1, First page：603, Last page：603, 03 Mar. 2011
  The Physical Society of Japan (JPS), Japanese
  ISSN：1342-8349, CiNii Articles ID：110008714428, CiNii Books ID：AA11439205
• 20pQH-11 Structural Phase Transition in YbAl_3C_3 and the Formation of a Spin-Gap　　　　　　　　　　　　　　　
  Matsumura T.; Inami T.; Kato Y.; Kosaka M.; Inukai T.; Ochiai A.; Nakao H.; Murakami Y.; Katano S.; Suzuki H.
  Meeting abstracts of the Physical Society of Japan, Volume：63, Number：2, First page：370, Last page：370, 25 Aug. 2008
  The Physical Society of Japan (JPS), Japanese
  ISSN：1342-8349, CiNii Articles ID：110006983828, CiNii Books ID：AA11439205
• 26aWP-6 Magnetism of YbCo_2Zn_<20> probed by muon spin relaxation　　　　　　　　　　　　　　　
  Higemoto W.; Ito T.U.; Ohishi K.; Satoh K.; Saiga Y.; Kosaka M.; Matsubayashi K.; Uwatoko Y.
  Meeting abstracts of the Physical Society of Japan, Volume：63, Number：1, First page：633, Last page：633, 29 Feb. 2008
  The Physical Society of Japan (JPS), Japanese
  ISSN：1342-8349, CiNii Articles ID：110007195577, CiNii Books ID：AA11439205
• 24aXA-5 Structural Phase Transition in YbAl_3C_3g : X-ray diffraction experiment　　　　　　　　　　　　　　　
  Matsumura T.; Kato Y.; Kosaka M.; Inami T.; Inukai T.; Ochiai A.; Nakao H.; Murakami Y.; Katano S.; Suzuki H.
  Meeting abstracts of the Physical Society of Japan, Volume：62, Number：2, First page：654, Last page：654, 21 Aug. 2007
  The Physical Society of Japan (JPS), Japanese
  ISSN：1342-8349, CiNii Articles ID：110007140886, CiNii Books ID：AA11439205
• 14aRC-4 Thermal Expansion and Magnetostriction of YbInCu_4 under High Pressure　　　　　　　　　　　　　　　
  Saiga Y; Nakano T; Hedo M; Uwatoko Y; Kosaka M; Mori N; Yoshimura K; Goto T
  Meeting Abstracts of the Physical Society of Japan, Volume：59, Number：0, First page：520, Last page：520, 2004
  The Physical Society of Japan, Japanese
  DOI ID：10.11316/jpsgaiyo.59.2.3.0_520_4, ISSN：1342-8349, CiNii Articles ID：110002054257, CiNii Books ID：AA11439205
• Magnetization of Eu_0.58Sr_0.42MnO₃ under high pressure　　　　　　　　　　　　　　　
  江藤徹二郎; 巨海玄道; SAMPATHKUMARAN E.V.; SUNDARESAN A.; 小坂昌史; 上床美也
  日本応用磁気学会学術講演概要集, Volume：24th (CD-ROM), 2000
  ISSN：1340-8100, J-Global ID：202102165940907568

• Ybジグザグ鎖をもつYbAgSe2の単結晶構造解析及び物性測定　　　　　　　　　　　　　　　
  青木優樹; 飯塚亮介; 道村真司; 小坂昌史
  Mar. 2021 - Mar. 2021
• イッテルビウム絶縁体YbAgS2の低次元磁性　　　　　　　　　　　　　　　
  飯塚亮介; 道村真司; 青木優樹; 石﨑嵩人; 山本隆文; 大山研司; 佐藤一彦; 小林拓矢; 谷口弘三; 髭本亘; 赤木暢; 大久保晋; 太田仁; 小坂昌史
  Mar. 2021
• 希土類絶縁体YbTS2(T:Ag,Cu)の磁気秩序　　　　　　　　　　　　　　　
  石﨑嵩人; 荒瀬将太朗; 野田新太; 山本隆文; 松川健; 大曲雄大; 鬼丸孝博; 飯塚亮介; 道村真司; 小坂昌史; 大山研司
  Sep. 2020
• 希土類硫化物CePd3S4の圧力効果　　　　　　　　　　　　　　　
  関根知也; 道村真司; 飯塚亮介; 小坂昌史
  Mar. 2020
• 希土類硫化物GdAgS2の物性　　　　　　　　　　　　　　　
  星野瑞希; 飯塚亮介; 道村真司; 小坂昌史
  Sep. 2019
• 希土類硫化物GdPd3S4のPt置換効果　　　　　　　　　　　　　　　
  道村真司; 関根知也; 飯塚亮介; 小坂昌史
  Sep. 2019
• 四極子秩序物質CePd3S4の圧力下磁化測定　　　　　　　　　　　　　　　
  関根知也; 道村真司; 飯塚亮介; 小坂昌史
  Sep. 2019
• 正方晶EuZn2Ge2の逐次相転移と磁気構造　　　　　　　　　　　　　　　
  道村真司; 平林輝; 飯塚亮介; 酒井俊; 小坂昌史; 増田亮; 中尾裕則; 本元悟; 桑原慶太郎
  Sep. 2019
• ジントル化合物Yb8Ge3Sb5の単結晶育成と物性　　　　　　　　　　　　　　　
  粕谷駿介; 沼倉凌介; 飯塚亮介; 道村真司; 小坂昌史
  Mar. 2019
• 希土類絶縁体YbAgS2の構造転移の研究　　　　　　　　　　　　　　　
  山本隆文; 杉本和哉; 大山研司; 飯塚亮介; 道村真司; 小坂昌史; 松川健; 星川晃範; 石垣徹
  Mar. 2019
• 二次元三角格子Yb硫化物YbAS2（A：アルカリ金属）の単結晶育成と物性　　　　　　　　　　　　　　　
  飯塚亮介; 沼倉凌介; 道村真司; 小坂昌史
  Mar. 2019
• 四極子秩序物質CePd3S4のAg置換物質の作成と物性　　　　　　　　　　　　　　　
  関根知也; 黒田翔馬; 飯塚亮介; 沼倉凌介; 道村真司; 小坂昌史
  Sep. 2018
• 希土類硫化物YbAgS2の低温下での粉末X線回折　　　　　　　　　　　　　　　
  飯塚亮介; 沼倉凌介; 星野瑞希; 道村真司; 小坂昌史
  Sep. 2018
• 単結晶SmTP(T=Ni,Pt)の物性と結晶場の推定　　　　　　　　　　　　　　　
  道村真司; 酒井俊; 飯塚亮介; 沼倉凌介; 小坂昌史
  Sep. 2018
• 正方晶EuZn2Ge2の粉末中性子回折　　　　　　　　　　　　　　　
  道村真司; 牛窪佑紀; 平林輝; 飯塚亮介; 沼倉凌介; 酒井俊; 小坂昌史; 片野進; 本元悟; 桑原慶太郎
  Sep. 2017
• 正方晶EuZn2Si2の単結晶育成と物性　　　　　　　　　　　　　　　
  小坂昌史; 牛窪佑紀; 道村真司; 沼倉凌介; 飯塚亮介; 片野進
  Sep. 2017
• 六方晶希土類化合物SmTP(T = Ni, Pt)の物性　　　　　　　　　　　　　　　
  酒井俊; 飯塚亮介; 沼倉凌介; 小坂昌史; 道村真司; 片野進
  Sep. 2017
• 正方晶希土類化合物Tb2MgSi2における中性子線回折　　　　　　　　　　　　　　　
  本田孝志; 沼倉凌介; 小坂昌史; 道村真司; 池田一貴; 大友季哉
  Sep. 2017
• 新規Eu化合物Eu2Si3Mg4の単結晶育成と物性　　　　　　　　　　　　　　　
  沼倉凌介; 牛窪佑紀; 小松慧士; 西川潮; 飯塚亮介; 酒井俊; 小坂昌史; 道村真司; 片野進
  Mar. 2017
• 正方晶希土類硫化物YbAgS2の磁性　　　　　　　　　　　　　　　
  飯塚亮介; 沼倉凌介; 小松慧士; 牛窪佑紀; 西川潮; 酒井俊; 粕谷駿介; 小坂昌史; 道村真司; 片野進
  Mar. 2017
• 20pPSB-18 Pt Subtitution Effects in Quadrupolar Ordering Compound CePd_3S_4　　　　　　　　　　　　　　　
  Nishikawa U.; Michimura S.; Kosaka M.; Katano S.; Numakura R.; Hirabayashi H.
  Meeting Abstracts of the Physical Society of Japan, 2016, The Physical Society of Japan (JPS)
  2016 - 2016, Japanese
• 22aPS-18 Magnetic and transport properties of tetragonal Sm_2MgSi_2　　　　　　　　　　　　　　　
  Numakura R.; Hirabayashi H.; Shibata K.; Motai C.; Ushikubo Y.; Komatsu K.; Nishikawa U.; Kosaka M.; Michimura S.; Katano S.
  Meeting Abstracts of the Physical Society of Japan, 2016, The Physical Society of Japan (JPS)
  2016 - 2016, Japanese
• Valence state and the lattice periodicity in hexagonal rare earth compound SmPtP　　　　　　　　　　　　　　　
  Sakai Shun; Sekiya Kahori; Numakura Ryosuke; Kosaka Masashi; Michimura Sinji; Katano Susumu
  Meeting Abstracts of the Physical Society of Japan, 2016, The Physical Society of Japan
  2016 - 2016, Japanese
  

  六方晶希土類化合物のSmPtPはR = Gd-Luのランタノイド収縮から外れている。同じくランタノイド収縮に従わないR = Eu は結晶の周期構造の変化と共に価数の秩序状態が変化し、結晶の周期性と価数の関係が注目されている。 今回、SmPtPのX線回折の結果からc軸に他の希土類の4倍の長周期性を発見した。さらに、磁化測定から見積もった有効ボーア磁子と飽和磁化の値からは価数混合状態が示唆される。 電気抵抗、比熱測定の結果と共に結晶の周期構造とSmの価数状態の関係に注目した講演を行う。

• 17aPS-83 Pressure effects on magnetic and transport properties of Yb_5Ge_4　　　　　　　　　　　　　　　
  Kosaka M.; Kirigane T.; Machida A.; Michimura S.; Katano S.; Wang B.; Matsubayashi K.; Uwatoko Y.
  Meeting Abstracts of the Physical Society of Japan, 2015, The Physical Society of Japan (JPS)
  2015 - 2015, Japanese
• 17aPS-82 Variable Range Hopping of the narrow gap semiconductor Yb_5Ge_4　　　　　　　　　　　　　　　
  Michimura S.; Machida A.; Kirigane T.; Kosaka M.; Katano S.
  Meeting Abstracts of the Physical Society of Japan, 2015, The Physical Society of Japan (JPS)
  2015 - 2015, Japanese
• 17aPS-98 The spin glass like behavior of tetragonal Gd_2MgSi_2, Tb_2MgSi_2　　　　　　　　　　　　　　　
  Numakura R.; Kosaka M.; Michimura S.; Katano S.
  Meeting Abstracts of the Physical Society of Japan, 2015, The Physical Society of Japan (JPS)
  2015 - 2015, Japanese
• 22aPS-123 Valence and physical properties of EuPd_3S_4 compound II　　　　　　　　　　　　　　　
  Tanahashi M.; Hirabayashi H.; Kosaka M.; Michimura S.; Katano S.
  Meeting Abstracts of the Physical Society of Japan, 2015, The Physical Society of Japan (JPS)
  2015 - 2015, Japanese
• 7pBJ-9 Semiconducting behavior and magnetic properties of tetragonal Yb_2MgSi_2　　　　　　　　　　　　　　　
  Numakura R.; Kosaka M.; Michimura S.; Katano S.; Nakajima D.; Nonaka R.; Wakabayashi Y.; Terashima T.; Ohta H.; Katori H. A.
  Meeting abstracts of the Physical Society of Japan, Aug. 2014, The Physical Society of Japan (JPS)
  Aug. 2014 - Aug. 2014, Japanese
• 10aBD-12 Yb valence state of Yb_5Ge_4 studied by Diffraction Anomalous Fine Structure (DAFS)　　　　　　　　　　　　　　　
  Michimura S.; Machida A.; Kirigane T.; Kosaka M.; Katano S.; Inami T.; Yamazaki Y.; Nakao H.
  Meeting abstracts of the Physical Society of Japan, Aug. 2014, The Physical Society of Japan (JPS)
  Aug. 2014 - Aug. 2014, Japanese
• 8aPS-58 Superconductivity and magnetism of (La_<1-x>, Ce_x)NiC_2　　　　　　　　　　　　　　　
  Shibata K.; Nakashima K.; Yoshimura H.; Katano S.; Kosaka M.; Michimura S.
  Meeting abstracts of the Physical Society of Japan, Aug. 2014, The Physical Society of Japan (JPS)
  Aug. 2014 - Aug. 2014, Japanese
• 8aPS-99 Single crystal growth and physical properties of EuPd_3S_4 compound　　　　　　　　　　　　　　　
  Tanahashi M.; Hirabayashi H.; Kosaka M.; michimura S.; Katano S.
  Meeting abstracts of the Physical Society of Japan, Aug. 2014, The Physical Society of Japan (JPS)
  Aug. 2014 - Aug. 2014, Japanese
• 8aPS-84 Effect of pressure and hydrogenation on magnetic semiconductor Yb_5Ge_4　　　　　　　　　　　　　　　
  Kirigane T.; Numakura R.; Machida A.; Kosaka M.; michimura S.; Katano S.; Kudo K.; Sakai M.
  Meeting abstracts of the Physical Society of Japan, Aug. 2014, The Physical Society of Japan (JPS)
  Aug. 2014 - Aug. 2014, Japanese
• 8aPS-87 Electrical resistivity of tetragonal R_2MgSi_2(R=Yb, Tm, Er)　　　　　　　　　　　　　　　
  Numakura R.; Kosaka M.; michimura S.; Katano S.; Nakajima D.; Nonaka R.; Wakabayashi Y.; Terashima T.; Ohta H.; Katori H. A.
  Meeting abstracts of the Physical Society of Japan, Aug. 2014, The Physical Society of Japan (JPS)
  Aug. 2014 - Aug. 2014, Japanese
• 28aPS-82 Crystal growth and characterization in RPd_3S_4 (R=Er, Tm, Yb)　　　　　　　　　　　　　　　
  Michimura S.; Matsuoka E.; Kosaka M.; Katano S.
  Meeting abstracts of the Physical Society of Japan, Mar. 2014, The Physical Society of Japan (JPS)
  Mar. 2014 - Mar. 2014, Japanese
• 28aPS-83 Physical properties of the tetragonal compound Tm_2MgSi_2　　　　　　　　　　　　　　　
  Numakura R.; Kosaka M.; Michimura S.; Katano S.
  Meeting abstracts of the Physical Society of Japan, Mar. 2014, The Physical Society of Japan (JPS)
  Mar. 2014 - Mar. 2014, Japanese
• Magnetic anisotropy of spinel compound GeFe_2O_4 single crystal　　　　　　　　　　　　　　　
  Ando Yuichi; Ohta Hiroto; Aruga Katori Hiroko; Tokunaga Masashi; Kosaka Masashi
  Meeting abstracts of the Physical Society of Japan, Aug. 2013, The Physical Society of Japan (JPS)
  Aug. 2013 - Aug. 2013, Japanese
• Study of a multipole ordering in RPd_3S_4(R=Ce,Dy) by resonant X-ray diffraction in the magnetic field　　　　　　　　　　　　　　　
  Michimura S.; Inami T.; Takaguti H.; Matsumura T.; Tanida H.; Sera M.; Matsuoka E.; Watahiki M.; Tanigaki K.; Onodera H.; Kosaka M.; Katan S.
  Meeting abstracts of the Physical Society of Japan, Aug. 2013, The Physical Society of Japan (JPS)
  Aug. 2013 - Aug. 2013, Japanese
• Physical properties of hexagonal EuNiP compound　　　　　　　　　　　　　　　
  Tanahashi M.; Hatanaka Y.; Machida A.; Koike A.; Kirigane T.; Kosaka M.; Michimura S.; Katano S.
  Meeting abstracts of the Physical Society of Japan, Aug. 2013, The Physical Society of Japan (JPS)
  Aug. 2013 - Aug. 2013, Japanese
• Magnetic properties of hexagonal RPtP(R=Gd,Ho,Yb) compound　　　　　　　　　　　　　　　
  Hatanaka Y.; Kosaka M.; Michimura S.; Tanahashi M.; Katano S.
  Meeting abstracts of the Physical Society of Japan, Aug. 2013, The Physical Society of Japan (JPS)
  Aug. 2013 - Aug. 2013, Japanese
• Magnetic properties and conductivities Yb_5Ge_4 and Yb_4LiGe_4　　　　　　　　　　　　　　　
  Machida A.; Kosaka M.; Michimura S.; Katano S.; Shirakawa N.
  Meeting abstracts of the Physical Society of Japan, Aug. 2013, The Physical Society of Japan (JPS)
  Aug. 2013 - Aug. 2013, Japanese
• Magnetic properties and conductivities of single crystal of Yb_5Ge_4　　　　　　　　　　　　　　　
  Machida A.; Kosaka M.; Michimura S.; Katano S.; Shirakawa N.
  Meeting abstracts of the Physical Society of Japan, Aug. 2013, The Physical Society of Japan (JPS)
  Aug. 2013 - Aug. 2013, Japanese
• 27aPS-54 Magnetic properties of tetragonal Yb_2MgSi_2　　　　　　　　　　　　　　　
  Hasegawa Y.; Machida A.; Imanari A.; Kosaka M.; Michimura S.; Katano S.; Kito H.
  Meeting abstracts of the Physical Society of Japan, Mar. 2013, The Physical Society of Japan (JPS)
  Mar. 2013 - Mar. 2013, Japanese
• 27aPS-49 Magnetic properties of hexagonal YbPtP compound　　　　　　　　　　　　　　　
  Hatanaka Y.; Kosaka M.; Michimura S.; Katano S.
  Meeting abstracts of the Physical Society of Japan, Mar. 2013, The Physical Society of Japan (JPS)
  Mar. 2013 - Mar. 2013, Japanese
• 27aPS-53 Single crystal growth and physical properities of Yb_5Ge_4　　　　　　　　　　　　　　　
  Machida A.; Kosaka M.; Michimura S.; Katano S.; Shirakawa N.
  Meeting abstracts of the Physical Society of Japan, Mar. 2013, The Physical Society of Japan (JPS)
  Mar. 2013 - Mar. 2013, Japanese
• 29aEN-1 Study of a multipole ordering in DyPd_3S_4 by resonant X-ray diffraction in the magnetic field　　　　　　　　　　　　　　　
  Michimura S.; Inami T.; Takaguti H.; Matsumura T.; Tanida H.; Sera M.; Matsuoka E.; Watahiki M.; Tanigaki K.; Onodera H.; Kosaka M.; Katano S.
  Meeting abstracts of the Physical Society of Japan, Mar. 2013, The Physical Society of Japan (JPS)
  Mar. 2013 - Mar. 2013, Japanese
• 20aPSB-33 X-ray magnetic scattering study of TbNiC_2　　　　　　　　　　　　　　　
  Shimomura S.; Nakao H.; Yamamoto N.; Nogami Y.; Hanasaki N.; Kosaka M.; Onodera H.
  Meeting abstracts of the Physical Society of Japan, Aug. 2012, The Physical Society of Japan (JPS)
  Aug. 2012 - Aug. 2012, Japanese
• 19pHC-9 Study of a multipole ordering in CePd_3S_4 by resonant X-ray diffraction with full polarization analysis　　　　　　　　　　　　　　　
  Michimura S.; Inami T.; Takaguti H.; Matsumura T.; Tanida H.; Sera M.; Matsuoka E.; Watahiki M.; Tanigaki K.; Onodera H.; Kosaka M.; Katano S.
  Meeting abstracts of the Physical Society of Japan, Aug. 2012, The Physical Society of Japan (JPS)
  Aug. 2012 - Aug. 2012, Japanese
• 20aPSB-20 Magnetic properties of Yb_4LiGe_4　　　　　　　　　　　　　　　
  Machida A.; Kirigane T.; tanahashi M.; Hasegawa Y.; Kosaka M.; Michimura S.; Katano S.
  Meeting abstracts of the Physical Society of Japan, Aug. 2012, The Physical Society of Japan (JPS)
  Aug. 2012 - Aug. 2012, Japanese
• 27pPSB-28 Magnetic properties of hexagonal RNiP compounds　　　　　　　　　　　　　　　
  Imanari A.; Kondo K.; Kosaka M.; Katano S.; Katori H.
  Meeting abstracts of the Physical Society of Japan, Mar. 2011, The Physical Society of Japan (JPS)
  Mar. 2011 - Mar. 2011, Japanese
• 26pPSA-32 Uniaxial Stress Control of Electric Polarization in Spin-Driven Ferroelectrics CuFe_<1-x>Ga_xO_2　　　　　　　　　　　　　　　
  Yoshitomi K.; Kaneko C.; Yamazaki H.; Nakajima T.; Mitsuda S.; Kosaka M.; Aso N.; Uwatoko Y.; Noda Y.; Matsuura M.; Terada N.; Wakimoto S.; Takeda M.; Kakurai K.
  Meeting abstracts of the Physical Society of Japan, Mar. 2011, The Physical Society of Japan (JPS)
  Mar. 2011 - Mar. 2011, Japanese
• 23pPSB-35 Pressure effects on T_c of the non-centrosymmetric superconductor LaNiC_2　　　　　　　　　　　　　　　
  Nakagawa Hideya; Imanari Ami; Kosaka Masashi; katano Susumu
  Meeting abstracts of the Physical Society of Japan, Aug. 2010, The Physical Society of Japan (JPS)
  Aug. 2010 - Aug. 2010, Japanese
• 23pPSA-51 Spontaneous strain in ferroquadrupolar phase of TmAu_2　　　　　　　　　　　　　　　
  Kosaka M.; Shida Y.; Imanari A.; Katano S.; Ohoyama K.; Onodera H.
  Meeting abstracts of the Physical Society of Japan, Aug. 2010, The Physical Society of Japan (JPS)
  Aug. 2010 - Aug. 2010, Japanese
• Effect of pressure on the physical properties of Ce_2Ni_5C_3　　　　　　　　　　　　　　　
  YAMADA A.; KONDO K.; KOSAKA M.; KATANO S.; MATSUBAYASHI K.; UWATOKO Y.
  May 2010
  May 2010 - May 2010, Japanese
• 22pPSA-44 Uniaxial Stress Effect on Magnetic Transitions in MagnetoFerroelectric Multiferroic CuFe_<1-x>Ga_xO_2　　　　　　　　　　　　　　　
  Yoshitomi Keisuke; Takahashi Keiichiro; Sano Manabu; Masuda Kazuya; Nakajima Taro; Mitsuda Setsuo; Kosaka Masashi; Aso Naohumi; Uwatoko Yoshiya
  Meeting abstracts of the Physical Society of Japan, Mar. 2010, The Physical Society of Japan (JPS)
  Mar. 2010 - Mar. 2010, Japanese
• 20pGD-4 Magnetoresistance in rare-earth intermetallic compounds RNiC_2　　　　　　　　　　　　　　　
  Hanasaki N.; Nogami Y.; Yokota K.; Mikami K.; Kakinuma M.; Shimomura S.; Kosaka M.; Onodera H.
  Meeting abstracts of the Physical Society of Japan, Mar. 2010, The Physical Society of Japan (JPS)
  Mar. 2010 - Mar. 2010, Japanese
• 25aPS-134 Development of susceptibility measurement system using TDO　　　　　　　　　　　　　　　
  Goto K.; Katano S.; Kosaka M.; Tozer S. W.
  Meeting abstracts of the Physical Society of Japan, Aug. 2009, The Physical Society of Japan (JPS)
  Aug. 2009 - Aug. 2009, Japanese
• 25aTJ-8 Effect of pressure on Ce_2Ni_5C_3　　　　　　　　　　　　　　　
  Yamada A.; Kondo K.; Kosaka M.; Katano S.; Matsubayashi K.; Uwatoko K.
  Meeting abstracts of the Physical Society of Japan, Aug. 2009, The Physical Society of Japan (JPS)
  Aug. 2009 - Aug. 2009, Japanese
• 22pQC-11 Effect of pressure on Ce_2Ni_5C_3　　　　　　　　　　　　　　　
  Yamada A.; Kondo K.; Kosaka M.; Katano S.; Matsubayashi K.; Uwatoko K.; Tozer S. W.
  Meeting abstracts of the Physical Society of Japan, Aug. 2008, The Physical Society of Japan (JPS)
  Aug. 2008 - Aug. 2008, Japanese
• 21aPS-91 Magnetization and resistivity of hexagonal Yb_2Sn　　　　　　　　　　　　　　　
  Kobiyama T.; Kondo K.; Yamada A.; Iwata K.; Kosaka M.; Katano S.; Kikkawa A.; Suzuki H. S.; Katori H.
  Meeting abstracts of the Physical Society of Japan, Aug. 2008, The Physical Society of Japan (JPS)
  Aug. 2008 - Aug. 2008, Japanese
• 22aQH-7 Neutron Diffraction Study in Spinel GeCo_2O_4 in magnetic field　　　　　　　　　　　　　　　
  Matsuda M.; Hoshi T.; Aruga Katori H.; Kosaka M.; Takagi H.
  Meeting abstracts of the Physical Society of Japan, Aug. 2008, The Physical Society of Japan (JPS)
  Aug. 2008 - Aug. 2008, Japanese
• Synthesis and physical properties of YbT_2Zn_<20> (T=Co, Rh, Ir)　　　　　　　　　　　　　　　
  SAIGA Yuta; MATSUBAYASHI Kazuyuki; FUJIWARA Tetsuya; KOSAKA Masashi; UWATOKO Yoshiya
  May 2008
  May 2008 - May 2008, Japanese
• 24aWK-7 Frustrated phenomena on YbAl_3C_3　　　　　　　　　　　　　　　
  Kosaka M.; Kato Y.; Kobiyama T.; Yamada A.; Katano S.; Ohoyama K.; Suzuki H.; Aso N.
  Meeting abstracts of the Physical Society of Japan, Feb. 2008, The Physical Society of Japan (JPS)
  Feb. 2008 - Feb. 2008, Japanese
• 23pPSB-7 Magnetization process of YbAl_3C_3　　　　　　　　　　　　　　　
  Kobiyama T.; Hoshi T.; Yamada A.; Kato Y.; Saiga Y.; Kosaka M.; Katano S.; Katori H.; Suzuki H.; Uwatoko Y.
  Meeting abstracts of the Physical Society of Japan, Feb. 2008, The Physical Society of Japan (JPS)
  Feb. 2008 - Feb. 2008, Japanese
• 23pPSB-10 Effect of magnetic field on YbCo_2Zn_<20>　　　　　　　　　　　　　　　
  Saiga Y.; Matsubayashi K.; Fujiwara T.; Kosaka M.; Katano S.; Uwatoko Y.
  Meeting abstracts of the Physical Society of Japan, Feb. 2008, The Physical Society of Japan (JPS)
  Feb. 2008 - Feb. 2008, Japanese
• 24aPS-32 Magnetic Properties of Sr_<3-x>Ca_xRu_2O_7　　　　　　　　　　　　　　　
  Iwata Kotaro; Yoshida Yoshiyuki; Kosaka Masashi; Katano Susumu
  Meeting abstracts of the Physical Society of Japan, Feb. 2008, The Physical Society of Japan (JPS)
  Feb. 2008 - Feb. 2008, Japanese
• 24aXA-7 Crystalline Electric Field of YbAl_3C_3　　　　　　　　　　　　　　　
  Kato Yoshiaki; Nowatari Hiromi; Kosaka Masashi; Katano Susumu; Ohoyama Kenji; Suzuki Hiroyuki; Aso Naofumi; Iwasa Kazuaki
  Meeting abstracts of the Physical Society of Japan, Aug. 2007, The Physical Society of Japan (JPS)
  Aug. 2007 - Aug. 2007, Japanese
• 22pPSB-57 Effect of pressure on the electrical resistivity of YbAl_2　　　　　　　　　　　　　　　
  Yamada A.; Nowatari H.; Saiga Y.; Kosaka M.; Katano S.; Kano M.; Uwatoko K.; Tozer S. W.
  Meeting abstracts of the Physical Society of Japan, Aug. 2007, The Physical Society of Japan (JPS)
  Aug. 2007 - Aug. 2007, Japanese
• 22pPSB-51 Specific heat measurement under pressure on YbCo_2Zn_<20>　　　　　　　　　　　　　　　
  Matsubayashi K.; Saiga Y.; Hedo M.; Umehara I.; Fujiwara T.; Kosaka M.; Katano S.; Uwatoko Y.
  Meeting abstracts of the Physical Society of Japan, Aug. 2007, The Physical Society of Japan (JPS)
  Aug. 2007 - Aug. 2007, Japanese
• 21pXA-4 Pressure induced transition in YbCo_2Zn_<20>　　　　　　　　　　　　　　　
  Saiga Y.; Matsubayashi K.; Fujiwara T.; Kosaka M.; Katano S.; Uwatoko Y.
  Meeting abstracts of the Physical Society of Japan, Aug. 2007, The Physical Society of Japan (JPS)
  Aug. 2007 - Aug. 2007, Japanese
• 18pPSA-63 Study of high temperature quadruple-ordering in YbAl_3C_3 : ^<27>Al-NMR/NQR　　　　　　　　　　　　　　　
  Tomisawa S.; Mito T.; Wada S.; Kato Y.; Kosaka M.
  Meeting abstracts of the Physical Society of Japan, Feb. 2007, The Physical Society of Japan (JPS)
  Feb. 2007 - Feb. 2007, Japanese
• 18pPSA-61 High Pressure Synthesis of YbAl_3C_3　　　　　　　　　　　　　　　
  Nowatari H.; Kato Y.; Kosaka M.; Katano S.; Kito H.; Suzuki H.
  Meeting abstracts of the Physical Society of Japan, Feb. 2007, The Physical Society of Japan (JPS)
  Feb. 2007 - Feb. 2007, Japanese
• 18aPS-85 Uniaxial Pressure Effect on Verwey Transition in Magnetite　　　　　　　　　　　　　　　
  Nagasawa Y.; Kosaka M.; Katano S.; Mori N.; Todo S.
  Meeting abstracts of the Physical Society of Japan, Feb. 2007, The Physical Society of Japan (JPS)
  Feb. 2007 - Feb. 2007, Japanese
• 18aWP-7 Physical properties of heavy fermion compound, YbCo_2Zn_<20>　　　　　　　　　　　　　　　
  Saiga Y.; Kosaka M.; Tomioka F.; Fujiwara T.; Hedo M.; Katano S.; Uwatoko Y.
  Meeting abstracts of the Physical Society of Japan, Feb. 2007, The Physical Society of Japan (JPS)
  Feb. 2007 - Feb. 2007, Japanese
• 18aWP-5 Inelastic Neutron Scattering of YbAl_3C_3　　　　　　　　　　　　　　　
  Kato Yoshiaki; Nowatari Hiromi; Kosaka Masashi; Katano Susumu; Ohoyama Kenji; Suzuki Hiroyuki; Aso Naofumi; Iwasa Kazuaki
  Meeting abstracts of the Physical Society of Japan, Feb. 2007, The Physical Society of Japan (JPS)
  Feb. 2007 - Feb. 2007, Japanese
• 26aZR-2 NMR/NQR study of YbAl_3C_3　　　　　　　　　　　　　　　
  Tomisawa S.; Mito T.; Wada S.; Kato Y.; Kosaka M.
  Meeting abstracts of the Physical Society of Japan, Aug. 2006, The Physical Society of Japan (JPS)
  Aug. 2006 - Aug. 2006, Japanese
• 23aPS-31 Magnetization measurement in Magnetite under Uniaxial Strain　　　　　　　　　　　　　　　
  Nagasawa Y.; Kosaka M.; Katano S.; Mori N.; Todo S.; Uwatoko Y.
  Meeting abstracts of the Physical Society of Japan, Aug. 2006, The Physical Society of Japan (JPS)
  Aug. 2006 - Aug. 2006, Japanese
• 22aPS-72 Uniaxial Pressure Effect on Electrical Resistivity in Magnetite　　　　　　　　　　　　　　　
  Hara R.; Nagasawa Y.; Seino T.; Kosaka M.; Mori N.; Todo S.; Uwatoko Y.
  Meeting abstracts of the Physical Society of Japan, Aug. 2005, The Physical Society of Japan (JPS)
  Aug. 2005 - Aug. 2005, Japanese
• 14pPSB-15 Magnetic properties of single crystalline YbAu_2　　　　　　　　　　　　　　　
  Kinoshita K; Koiwai S; Kato Y; Kosaka M; Mori N
  Meeting abstracts of the Physical Society of Japan, Aug. 2004, The Physical Society of Japan (JPS)
  Aug. 2004 - Aug. 2004, Japanese
• 15aRA-6 Anomalous magnetic structure of Ce_3PbC　　　　　　　　　　　　　　　
  Kosaka M; Saitoh K; Mori N; Uwatoko Y; Onodera H; Tobo A.; Ohoyama K
  Meeting abstracts of the Physical Society of Japan, Aug. 2004, The Physical Society of Japan (JPS)
  Aug. 2004 - Aug. 2004, Japanese
• 13aPS-99 Effect of uniaxial pressure on the electrical resistivity of magnetite around the Verwey transition　　　　　　　　　　　　　　　
  Hara Ryohei; Seino Toshiaki; Kosaka Masashi; Todo Sakae; Uwatoko Yoshiya; Mori Nobuo
  Meeting abstracts of the Physical Society of Japan, Aug. 2004, The Physical Society of Japan (JPS)
  Aug. 2004 - Aug. 2004, Japanese
• 28pPSA-17 Effect of pressure on the electrical resistivity and magnetization of Ce_2Ni_5C_3　　　　　　　　　　　　　　　
  Kato Yoshiaki; Kosaka Masashi; Mori Nobuo
  Meeting abstracts of the Physical Society of Japan, Mar. 2004, The Physical Society of Japan (JPS)
  Mar. 2004 - Mar. 2004, Japanese
• 14aRC-4 Thermal Expansion and Magnetostriction of YbInCu_4 under High Pressure　　　　　　　　　　　　　　　
  Saiga Y; Nakano T; Hedo M; Uwatoko Y; Kosaka M; Mori N; Yoshimura K; Goto T
  Meeting Abstracts of the Physical Society of Japan, 2004, The Physical Society of Japan
  2004 - 2004, Japanese
• Effect of uniaxial pressure on Verwey transition of magnetite　　　　　　　　　　　　　　　
  Seino Toshiaki; Hara Ryohei; Kosaka Masashi; Mori Nobuo; Todo Sakae; Uwatoko Yoshiya
  Meeting abstracts of the Physical Society of Japan, Aug. 2003, The Physical Society of Japan (JPS)
  Aug. 2003 - Aug. 2003, Japanese
• High pressure and low temperature experiments using helium pressure transmitting medium III　　　　　　　　　　　　　　　
  ISHII Yasuyuki; KOSAKA Masashi; MORI Nobuo; UWATOKO Yoshiya; HEDO Masato
  Meeting abstracts of the Physical Society of Japan, Aug. 2002, The Physical Society of Japan (JPS)
  Aug. 2002 - Aug. 2002, Japanese
• Magnetic structure of Ce3PbC　　　　　　　　　　　　　　　
  Kosaka M.; Koiwai S.; Mori N.; Uwatoko Y.; Onodera H.; Ohoyama K.; Tobo A.; Yamaguchi Y.
  Meeting abstracts of the Physical Society of Japan, Aug. 2002, The Physical Society of Japan (JPS)
  Aug. 2002 - Aug. 2002, Japanese
• Magnetic field and Pressure effect of CeGa　　　　　　　　　　　　　　　
  Koiwai S.; Kosaka M.; Mori N.
  Meeting abstracts of the Physical Society of Japan, Aug. 2002, The Physical Society of Japan (JPS)
  Aug. 2002 - Aug. 2002, Japanese
• Neutron Diffraction of Ce2SC3Ge4 Single Crystal　　　　　　　　　　　　　　　
  Yokoyama M.; Kosaka M.; Mori N.; Aso N.; Nishi M.; Hedo M.; Uwatoko Y.
  Meeting abstracts of the Physical Society of Japan, Aug. 2002, The Physical Society of Japan (JPS)
  Aug. 2002 - Aug. 2002, Japanese
• Pressure effect on the ferromagnetic cerium compound CeCu9Sn4　　　　　　　　　　　　　　　
  ISHII Yasuyuki; KOSAKA Masashi; MORI Nobuo; UWATOKO Yoshiya; HEDO Masato
  Meeting abstracts of the Physical Society of Japan, Aug. 2002, The Physical Society of Japan (JPS)
  Aug. 2002 - Aug. 2002, Japanese
• 24aPS-82 High pressure and low temperature experiments using helium pressure transmitting medium II　　　　　　　　　　　　　　　
  ISHII Yasuyuki; KOSAKA Masashi; MORI Nobuo; TANIGUCHI Hiromi; UWATOKO Yoshiya; HEDO Masato
  Meeting abstracts of the Physical Society of Japan, Mar. 2002, The Physical Society of Japan (JPS)
  Mar. 2002 - Mar. 2002, Japanese
• Neutron scattering of Ce_3PbC　　　　　　　　　　　　　　　
  Kosaka M.; Koiwai S.; Mori N.; Uwatoko Y.; Onodera H.; Ohoyama K.; Yamaguchi Y.
  Meeting abstracts of the Physical Society of Japan, Sep. 2001, The Physical Society of Japan (JPS)
  Sep. 2001 - Sep. 2001, Japanese
• Magnetic properties of RMo_2Al_4(R=Ce, Ho, Er, Tm)　　　　　　　　　　　　　　　
  MIYAUCHI Yutaka; KOSAKA Masashi; MORI Nobuo; UWATOKO Yoshiya
  Meeting abstracts of the Physical Society of Japan, Sep. 2001, The Physical Society of Japan (JPS)
  Sep. 2001 - Sep. 2001, Japanese
• Evidence of the anisotropically developed antiferromagentic spin fluctuation in CeFe_2 under high pressures　　　　　　　　　　　　　　　
  Fujiwara T.; Fujii H.; Ishii Y.; Koiwai S.; Kosaka M.; Uwatoko Y.; Nishi M.; Kakurai K.
  Meeting abstracts of the Physical Society of Japan, Sep. 2001, The Physical Society of Japan (JPS)
  Sep. 2001 - Sep. 2001, Japanese
• High pressure and low temperature experiments using helium pressure transmitting medium　　　　　　　　　　　　　　　
  ISHII Yasuyuki; KOSAKA Masashi; MORI Nobuo; Uwatoko Yoshiya
  Meeting abstracts of the Physical Society of Japan, Sep. 2001, The Physical Society of Japan (JPS)
  Sep. 2001 - Sep. 2001, Japanese
• Thermal analysis of single crystal CeZn_<1-x>Cu_x　　　　　　　　　　　　　　　
  Ohshima S.; Ishii Y.; Kosaka M.; Uwatoko Y.
  Meeting abstracts of the Physical Society of Japan, Mar. 2001, The Physical Society of Japan (JPS)
  Mar. 2001 - Mar. 2001, Japanese
• Crystalline electric field of Ce_3SnC　　　　　　　　　　　　　　　
  Kosaka M.; Uwatoko Y.; Onodera H.; Ohoyama K.; Yamaguchi Y.; Mori N.
  Meeting abstracts of the Physical Society of Japan, Mar. 2001, The Physical Society of Japan (JPS)
  Mar. 2001 - Mar. 2001, Japanese
• Heatcapacity of (Fe_<1-x>Ru_x)_2P　　　　　　　　　　　　　　　
  MIYAUCHI Yutaka; KOSAKA Masashi; UWATOKO Yoshiya; FUJII Hironobu
  Meeting abstracts of the Physical Society of Japan, Mar. 2001, The Physical Society of Japan (JPS)
  Mar. 2001 - Mar. 2001, Japanese
• Magnetic properties of Eu_<0.58>Sr_<0.42>MnO_3 under high pressure and high magnetic field　　　　　　　　　　　　　　　
  Eto T.; Honda F.; Oomi G.; Kagayama T.; Sundaresan A.; Sampathkumaran E.; Kosaka M.; Uwatoko Y.
  Meeting abstracts of the Physical Society of Japan, Mar. 2001, The Physical Society of Japan (JPS)
  Mar. 2001 - Mar. 2001, Japanese
• High pressure investigation using Helium pressure transmitting medium　　　　　　　　　　　　　　　
  ISHII Yasuyuki; UWATOKO Yoshiya; KOSAKA Masashi; MORI Nobuo
  Meeting abstracts of the Physical Society of Japan, Mar. 2001, The Physical Society of Japan (JPS)
  Mar. 2001 - Mar. 2001, Japanese
• Development of pressure at ^3He temperature under high magnetic fields.　　　　　　　　　　　　　　　
  Kosaka M.; Uchida A.; Ishii Y.; Yokoyama M.; Koiwai S.; Miyauchi Y.; Seino T.; Uwatoko Y.; Oomi G.; Mori N.; Matsumoto T.
  Meeting abstracts of the Physical Society of Japan, Mar. 2001, The Physical Society of Japan (JPS)
  Mar. 2001 - Mar. 2001, Japanese
• Magnetism and Effect of Pressure of Single Crystal YbSb_2　　　　　　　　　　　　　　　
  KOIWAI Sadayoshi; KOSAKA Masasi; UWATOKO Yoshiya; YAMAGUTI Yuuji; SIRAKAWA Naoki
  Meeting abstracts of the Physical Society of Japan, Mar. 2001, The Physical Society of Japan (JPS)
  Mar. 2001 - Mar. 2001, Japanese
• Anomalous magnetic susceptibilities of TbB_2C_2　　　　　　　　　　　　　　　
  Kaneko K.; Onodera H.; Kosaka M.; Yamauchi H.; Yamaguchi Y.
  Meeting abstracts of the Physical Society of Japan, Mar. 2001, The Physical Society of Japan (JPS)
  Mar. 2001 - Mar. 2001, Japanese
• Magnetism of a layered perovskite ruthenates under uniaxial pressures　　　　　　　　　　　　　　　
  Ikeda S. I.; Shirakawa N.; Uchida A.; Kosaka M.; Koiwai S.; Uwatoko Y.
  Meeting abstracts of the Physical Society of Japan, Mar. 2001, The Physical Society of Japan (JPS)
  Mar. 2001 - Mar. 2001, Japanese
• Transport properties of rare earth hydride films under high pressure　　　　　　　　　　　　　　　
  MIYAUCHI Yutaka; UCHIDA Ahimusa; NAKASHIMA Hirotake; KOSAKA Masashi; UWATOKO Yoshiya; KONTANI Wataru; SAKAI Masamichi; OBI Toshihisa; TAKANASHI Hiroki
  Meeting abstracts of the Physical Society of Japan, Sep. 2000, The Physical Society of Japan (JPS)
  Sep. 2000 - Sep. 2000, Japanese
• Thermal expansion study of DyB_2C_2 under high pressure　　　　　　　　　　　　　　　
  Kosaka M.; Uwatoko A. Y.; Honda F.; Kagayama T.; Oomi G.; Onodera H.; Yamauchi H.; Yamaguchi Y.
  Meeting abstracts of the Physical Society of Japan, Sep. 2000, The Physical Society of Japan (JPS)
  Sep. 2000 - Sep. 2000, Japanese
• Pressure effect of CeB_6　　　　　　　　　　　　　　　
  Sera M.; Uwatoko Y.; Miyauti H.; Hane S.; Goto T.; Kunii S.
  Meeting abstracts of the Physical Society of Japan, Sep. 2000, The Physical Society of Japan (JPS)
  Sep. 2000 - Sep. 2000, Japanese
• Field Dependent Specific Heat of YbInCu_4　　　　　　　　　　　　　　　
  UCHIA Ahimusa; KOSAKA Masasi; UWATOKO Yosiya; OOMI Gendo; MORI Nobuo; MATSUMOTO Takehiko; SARRA Jon.; Thompson Joe. D.
  Meeting abstracts of the Physical Society of Japan, Sep. 2000, The Physical Society of Japan (JPS)
  Sep. 2000 - Sep. 2000, Japanese
• Pressure effect of YbT_2Si_2(T=Ir,Rh) and YbNiSi_3　　　　　　　　　　　　　　　
  Muranaka T.; Fukuda T.; Akimitsu J.; Uchida A.; Kosaka M.; Uwatoko Y.
  Meeting abstracts of the Physical Society of Japan, Sep. 2000, The Physical Society of Japan (JPS)
  Sep. 2000 - Sep. 2000, Japanese
• High-pressure investigation of Ce-intermetallic compound using Helium pressure transmitting medium　　　　　　　　　　　　　　　
  ISHII Yasuyuki; KOSAKA Masashi; UWATOKO Yoshiya; MORI Nobuo
  Meeting abstracts of the Physical Society of Japan, Sep. 2000, The Physical Society of Japan (JPS)
  Sep. 2000 - Sep. 2000, Japanese
• Magnetism of a layered perovskite molybdate under high pressures　　　　　　　　　　　　　　　
  Ikeda S. I.; Shirakawa N.; Hase I.; Kosaka M.; Koiwai S.; Uwatoko Y.
  Meeting abstracts of the Physical Society of Japan, Sep. 2000, The Physical Society of Japan (JPS)
  Sep. 2000 - Sep. 2000, Japanese
• Study of megnetism of CeRh_2Si_2 under high pressure probed by μSR　　　　　　　　　　　　　　　
  Higemoto W.; Satoh K.; Koda A.; Shimomura K.; Nishiyama K.; Koiwai S.; Kosaka M.; Uwatoko Y.; Mohri N.
  Meeting abstracts of the Physical Society of Japan, Sep. 2000, The Physical Society of Japan (JPS)
  Sep. 2000 - Sep. 2000, Japanese
• Magnetization of Eu_<0.58>Sr_<0.42>MnO_3 under high pressure　　　　　　　　　　　　　　　
  ETO T.; OOMI G.; SAMPATHKUMARAN E. V.; SUNDARESAN A.; KOSAKA M.; UWOTOKO Y.
  Sep. 2000
  Sep. 2000 - Sep. 2000, Japanese
• Effect of Pressure on the Magnetization of Single Crystal CeB_6 II　　　　　　　　　　　　　　　
  Uwatko Y.; Kosaka M.; Goto T.; Sera M.; Kunii A.
  Meeting abstracts of the Physical Society of Japan, Mar. 2000, The Physical Society of Japan (JPS)
  Mar. 2000 - Mar. 2000, Japanese
• Effect of pressure on antiferroquadrupolar compound DyB_2C_2　　　　　　　　　　　　　　　
  Kosaka M.; Uchida A.; Uwatoko Y.; Onodera H.; Yamauchi H.; Yamaguchi Y.
  Meeting abstracts of the Physical Society of Japan, Mar. 2000, The Physical Society of Japan (JPS)
  Mar. 2000 - Mar. 2000, Japanese
• Magnetic structure of Ce_3SnC　　　　　　　　　　　　　　　
  Kosaka M.; Koiwai S.; Uwatoko Y.; Onodera H.; Ohoyama K.; Yamaguchi Y.; Suzuki H.; Kitazawa H.; Kido G.; Katori H.; Katsumata K.; Takeshita N.; Mori N.
  Meeting abstracts of the Physical Society of Japan, Mar. 2000, The Physical Society of Japan (JPS)
  Mar. 2000 - Mar. 2000, Japanese
• Magnetic Properties of Ce_2Sc_3M_4(M=Si, Ge) Single Crystals　　　　　　　　　　　　　　　
  YOKOYAMA Masaki; SHIRO Masanori; TAKESHITA Nao; MORI Nobuo; KOSAKA Masashi; UWATOKO Yoshiya
  Meeting Abstracts of the Physical Society of Japan, 2000, The Physical Society of Japan
  2000 - 2000, Japanese
• Effect of Pressure on the Strong Correlated Intermetallic Compound YbInCu4　　　　　　　　　　　　　　　
  上床 美也; 内田 安陽夢生; 小坂 昌史
  CACS forum, Dec. 1999
  Dec. 1999 - Dec. 1999, Japanese
  High-pressure apparatuses have been designed to measure the electrical and magnetic properties of condensed matters. The apparatuses for electrical and magnetic measurements can be used at least up to 33 kbar at down to 1.5 K and 12 kbar at down to 1.8 K with SQUID Magnetometer (by Quantum Design), respectively. Applications of these apparatuses to measure the electrical resisivity and magnetizationfor YbInCu4 are briefly described.
• 27aS-9 Mossbauer spectroscopy and neutram diffraction of single crystal (Fe_<1-x>Ru_x)_2P　　　　　　　　　　　　　　　
  Oki T; Kosaka M; Fujii H; Onodera S; Uwatoko Y
  Meeting abstracts of the Physical Society of Japan, Sep. 1999, The Physical Society of Japan (JPS)
  Sep. 1999 - Sep. 1999, Japanese
• 25pPSA-29 Effect of Pressure on the Ce_3Cu_3Sb_4　　　　　　　　　　　　　　　
  Uchida A; Kosaka M; Uwatoko Y
  Meeting abstracts of the Physical Society of Japan, Sep. 1999, The Physical Society of Japan (JPS)
  Sep. 1999 - Sep. 1999, Japanese
• 29p-PSA-37 Effect of Pressure on the Magnetic Properties of CeGa Single Crystal　　　　　　　　　　　　　　　
  Matsuoka E.; Kosaka M.; Suzuki H.; Kitazawa H.; Kido G.; Takeshita N.; Mori N.; Uwatoko Y.
  Meeting abstracts of the Physical Society of Japan, Mar. 1999, The Physical Society of Japan (JPS)
  Mar. 1999 - Mar. 1999, Japanese
• 28a-PS-31 High field magnetization of Ce_3SnC　　　　　　　　　　　　　　　
  Kosaka M.; Seino T.; Uwatoko Y.; Onodera H.; Suzuki H.; Kitazawa H.; Kido G.; Taketomi H.; Takeshita N.; Mori N.
  Meeting abstracts of the Physical Society of Japan, Mar. 1999, The Physical Society of Japan (JPS)
  Mar. 1999 - Mar. 1999, Japanese
• 31a-R-11 Magnetization of single crystailine Sr_3Ru_2O_7 under hydrostatic pressure　　　　　　　　　　　　　　　
  Ikeda S.; Maeno Y.; Kosaka M.; Uwatoko Y.
  Meeting abstracts of the Physical Society of Japan, Mar. 1999, The Physical Society of Japan (JPS)
  Mar. 1999 - Mar. 1999, Japanese
• Magnetic Properties of CeScSi Single Crystal :　　　　　　　　　　　　　　　
  UWATOKO Yoshiya; KOSAKA Masashi; YOKOYAMA Masaaki; SHIGEOKA Toru; SUZUKI Hiroyuki; KITAZAWA Hideaki; KIDO Giyuu; OOMI Gendo; MORI Nobuo
  JJAP series, 1999, Japanese Journal of Applied Physics
  1999 - 1999, English
• Magnetic properties of Ce_3SnC　　　　　　　　　　　　　　　
  KOSAKA M.; SUZUKI I.; UWATOKO Y.; ONODERA H.
  Meeting abstracts of the Physical Society of Japan, Sep. 1998, The Physical Society of Japan (JPS)
  Sep. 1998 - Sep. 1998, Japanese
• Effect of pressure on ferroquadrupolar compound TmAu_2　　　　　　　　　　　　　　　
  KOSAKA M.; UWATOKO Y.; SEINO T.; ONODERA H.; OHOYAMA K.; YAMAGUCHI Y.; OHASHI M.
  Meeting abstracts of the Physical Society of Japan, Sep. 1998, The Physical Society of Japan (JPS)
  Sep. 1998 - Sep. 1998, Japanese
• Magnetic H-T phase diagram of tetragonal DyB_2C_2　　　　　　　　　　　　　　　
  YAMAUCHI H.; ONODERA H.; KOSAKA M.; ONIMARU T.; OHASI M.; YAMAGUCHI Y.
  Meeting abstracts of the Physical Society of Japan, Mar. 1998, The Physical Society of Japan (JPS)
  Mar. 1998 - Mar. 1998, Japanese
• 6a-PS-68 Basal-plane magnetic anisotropy in tetragonal of RB_2C_2.　　　　　　　　　　　　　　　
  Yamauchi H.; Onodera H.; Kosaka M.; Onimaru T.; Ohasi M.; Yamaguchi Y.
  Meeting abstracts of the Physical Society of Japan, Sep. 1997, The Physical Society of Japan (JPS)
  Sep. 1997 - Sep. 1997, Japanese
• 6a-PS-70 Magnetic properties of single-crystalline RB_2C_2(R=Ce, Pr and Nd).　　　　　　　　　　　　　　　
  Onimaru T.; Onodera H.; Kosaka M.; Yamauchi H.; Ohasi M.; Yamaguchi Y.
  Meeting abstracts of the Physical Society of Japan, Sep. 1997, The Physical Society of Japan (JPS)
  Sep. 1997 - Sep. 1997, Japanese
• 6a-YK-13 Quadrupolar ordering and magnetic properties of tetragonal DyB_2C_2.　　　　　　　　　　　　　　　
  Yamauchi H.; Onodera H.; Kosaka M.; Onimaru T.; Ohasi M.; Yamaguchi Y.
  Meeting abstracts of the Physical Society of Japan, Sep. 1997, The Physical Society of Japan (JPS)
  Sep. 1997 - Sep. 1997, Japanese
• 28p-PSA-20 Neutron diffraction of quadrupolar ordered phase in TmAu_2　　　　　　　　　　　　　　　
  Kosaka M.; Onodera H.; Ohoyama K.; Ohashi M.; Yamaguchi Y.
  Meeting abstracts of the Physical Society of Japan, Mar. 1997, The Physical Society of Japan (JPS)
  Mar. 1997 - Mar. 1997, Japanese
• 28p-PSA-28 Magnetic Properties of RB_2C_2　　　　　　　　　　　　　　　
  Yamauchi H.; Onodera H.; Kosaka M.; Yamaguchi Y.
  Meeting abstracts of the Physical Society of Japan, Mar. 1997, The Physical Society of Japan (JPS)
  Mar. 1997 - Mar. 1997, Japanese
• 1a-pS-70 Magnetic properties of single crystal TmAu_2III　　　　　　　　　　　　　　　
  Kosaka M.; Onodera H.; Ohoyama K.; Ohashi M.; Yamaguchi Y.; Nakamura S.; Goto T.
  Abstracts of the meeting of the Physical Society of Japan. Annual meeting, Mar. 1996, The Physical Society of Japan (JPS)
  Mar. 1996 - Mar. 1996, Japanese
• Magnetic properties of single crystal TmAu_2II　　　　　　　　　　　　　　　
  Kosaka M.; Onodera H.; Ohoyama K; Ohashi M.; Yamaguchi Y.; Nakamura S.; Goto T.
  Abstracts of the meeting of the Physical Society of Japan. Sectional meeting, Sep. 1995, The Physical Society of Japan (JPS)
  Sep. 1995 - Sep. 1995, Japanese
• Magentic properties of single crystal TmCu_2Si_2 and TmAu_2　　　　　　　　　　　　　　　
  Kosaka M.; Onodera H.; Ohoyama K.; Yamaguchi Y.; Nakamura S.; Goto T.
  Abstracts of the meeting of the Physical Society of Japan. Annual meeting, Mar. 1995, The Physical Society of Japan (JPS)
  Mar. 1995 - Mar. 1995, Japanese
• 4a-PS-20 Magnetic properties of single crystal TmCu_2Si_2 II　　　　　　　　　　　　　　　
  Kosaka M; Onoderam H; Ohoyama K; Yamaguchi Y
  Abstracts of the meeting of the Physical Society of Japan. Sectional meeting, Aug. 1994, The Physical Society of Japan (JPS)
  Aug. 1994 - Aug. 1994, Japanese
• 29a-PS-16 Magnetic properties of single crystal TmCu_2Si_2　　　　　　　　　　　　　　　
  Kosaka M; Onodera H; Yamaguchi Y
  Abstracts of the meeting of the Physical Society of Japan. Annual meeting, Mar. 1994, The Physical Society of Japan (JPS)
  Mar. 1994 - Mar. 1994, Japanese

• 量子スピン4f電子系梯子格子物質で観測する1次元から2次元へのクロスオーバー　　　　　　　　　　　　　　　
  Apr. 2024 - Mar. 2028
  Principal investigator
  Grant amount(Total)：4680000, Direct funding：3600000, Indirect funding：1080000
  Grant number：24K06932
• Study of quantum spin liquid in two-dimensional triangular-lattice ytterbium compounds　　　　　　　　　　　　　　　
  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), 01 Apr. 2018 - 31 Mar. 2022
  Kosaka Masashi, Saitama University
  Grant amount(Total)：4290000, Direct funding：3300000, Indirect funding：990000
  A quantum spin liquid state, which shows the strong correlation among the spins but does not order magnetically even at absolute zero temperature, is regarded as a new magnetic state. We synthesized the insulating compound KYbS2, where Yb3+ ions with the effective spin-1/2 form a two-dimensional triangular lattice. From our measurements in the low temperature region, we have demonstrated that KYbS2 is the spin liquid candidate. Furthermore, we also found that YbAgS2 shows the development of short-range magnetic correlations, which arises from one-dimensional chains of Yb3+ ions.
  Grant number：18K03504
• Study of magnetic frustration in the lithium-substituted rare-earth compounds　　　　　　　　　　　　　　　
  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), 01 Apr. 2012 - 31 Mar. 2015
  KOSAKA Masashi; MICHIMURA Shinji; OHOYAMA Kenji; NAKANISHI Yoshiki; HIGEMOTO Wataru; KITO Hijiri, Saitama University
  Grant amount(Total)：5070000, Direct funding：3900000, Indirect funding：1170000
  We found that the intermetallic compound Yb5Ge4 indicates the development of short-range correlations caused by magnetic frustration. Yb5Ge4 is the mother material of Yb4LiGe4, which is designed to reinforce the magnetic frustration effects performed by the Li-substitution. The diffraction anomalous fine structure method (DAFS), X-ray structural technique, reveals one of three crystallographic sites of Yb ions occupies the Yb3+ state and the other sites are in the Yb2+ state. The valence-ordered state already realizes at room temperatures, therefore, the low-dimensional magnetic network has been formed by Yb3+ ions. The anomalous behaviors in the temperature dependences of magnetization and specific heat of Yb5Ge4 are due to the development of short-range magnetic correlations, which arises from low-dimensionality effects of magnetic interactions.
  Grant number：24540359
• Study of frustrated rare-earth intermetallic compounds　　　　　　　　　　　　　　　
  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), 2008 - 2010
  KOSAKA Masashi; OHOYAMA Kenji; MITO Takeshi; MATSUMURA Takeshi; SUZUKI Hiroyuki; METOKI Naoto; YOSHIZAWA Masahito; NAKANISHI Yoshiki, Saitama University
  Grant amount(Total)：4420000, Direct funding：3400000, Indirect funding：1020000
  We found that the intermetallic compound YbAl_3C_3 exhibits an spin-singlet ground state at low temperatures. The structure of the first excited triplet state, which develops rapidly below 10K, is directly clarified by inelastic neutron scattering experiments with a higher energy resolution. The spin-singlet ground state has never been observed in 4f electron systems. The two-dimensional frustrated triangular lattice and the low carrier density play an important role in the realization of the spin-singlet ground state. In order to investigate physical properties of YbAl_3C_3, we have performed synchrotron X-ray diffraction, NMR・NQR, specific heat, magnetization, electrical resistivity and elastic constant measurements.
  Grant number：20540344
• 液体窒素温度を越える高温で四極子秩序転移を示すイッテルビウム炭化物の研究　　　　　　　　　　　　　　　
  2006 - 2008
  Grant amount(Total)：27170000, Direct funding：20900000, Indirect funding：6270000
  Grant number：18684019
• 先端超高圧技術を用いた特異な有機超伝導体の研究　　　　　　　　　　　　　　　
  2006 - 2007
  Grant amount(Total)：4100000, Direct funding：4100000
  Grant number：18028007
• 有機物質における新規圧力誘起超伝導体の開発と超伝導発現機構の解明　　　　　　　　　　　　　　　
  2004 - 2005
  Grant amount(Total)：4900000, Direct funding：4900000
  Grant number：16038207
• Ce_3PbCにおける互いに独立な磁気構造の逐次転移の起源　　　　　　　　　　　　　　　
  2003 - 2004
  Grant amount(Total)：3600000, Direct funding：3600000
  Grant number：15740197
• 塑性変形限界を利用した4GPa級非磁性ピストンシリンダー型高圧装置の試作　　　　　　　　　　　　　　　
  2001 - 2002
  Grant amount(Total)：800000, Direct funding：800000
  Grant number：13874041
• 層状ペロブスカイト遷移金属酸化物の圧力による軌道の自由度の制御　　　　　　　　　　　　　　　
  2000 - 2001
  Grant amount(Total)：3700000, Direct funding：3700000
  Grant number：12046215
• 立方晶Ce_3SnCの悪魔の階段(多段メタ磁性転移)の起源　　　　　　　　　　　　　　　
  2000 - 2001
  Grant amount(Total)：2100000, Direct funding：2100000
  Grant number：12740201
• 薄膜希土類水素化物における新機能材料の探索と圧力効果の研究　　　　　　　　　　　　　　　
  2000 - 2000
  Grant amount(Total)：2100000, Direct funding：2100000
  Grant number：12022211
• 圧力誘起水素化物超伝導体と新機能材料の探索とその物性研究　　　　　　　　　　　　　　　
  1999 - 1999
  Grant amount(Total)：2100000, Direct funding：2100000
  Grant number：11135207
• フラックス法を用いた純良単結晶作成法の新しい試み　　　　　　　　　　　　　　　
  1998 - 1999
  Grant amount(Total)：2100000, Direct funding：2100000
  Grant number：10874050