仲村 愛*; 平仲 裕一*; 辺土 正人*; 仲間 隆男*; 三浦 泰直*; 堤 泰樹*; 森 晶宣*; 石田 一裕*; 三田村 勝哉*; 広瀬 雄介*; et al.
JPS Conference Proceedings (Internet), 3, p.011012_1 - 011012_6, 2014/06
Two europium compounds with the same structure EuGa and EuAl have been investigated. The Fermi surfaces revealed experimentally show a peculiar feature: flat Fermi surface sheets appear parallel to the tetragonal  planes. Reflecting this, a charge density wave transition due to the nesting of Fermi surface sheets has been observed in EuAl.
仲村 愛*; 平仲 裕一*; 辺土 正人*; 仲間 隆男*; 立津 慶幸*; 眞榮平 孝裕*; 三浦 泰直*; 森 晶宣*; 堤 泰樹*; 広瀬 雄介*; et al.
Journal of the Physical Society of Japan, 82(12), p.124708_1 - 124708_6, 2013/12
Fermi surfaces and magnetic properties of an antiferromagnet EuBi were investigated on a flux-grown single crystal. A critical magnetic field of 225 kOe where the magnetic moments are forced to align ferromagnetically was well explained by the magnetic exchange interaction based on a two-sublattice model. The Fermi surface characteristics are in agreement with the theoretical prediction indicating a fully magnetic divalent state in Eu atoms.
仲村 愛*; 平仲 裕一*; 辺土 正人*; 仲間 隆男*; 三浦 泰直*; 堤 泰樹*; 森 晶宣*; 石田 一裕*; 三田村 勝哉*; 広瀬 雄介*; et al.
Journal of the Physical Society of Japan, 82(10), p.104703_1 - 104703_10, 2013/10
High quality single crystals of EuGa have been grown from Ga flux. Electrical resistivity, magnetic susceptibility, high-field magnetization, specific heat, thermoelectric power and de Haas-van Alphen effect were investigated. Antiferromagnetic transition due to divalent Eu atoms were observed at 16.5 K. A charge density wave transition was also found under high pressure accompanied by a Fermi surface reconstruction. These observations were fully accounted for by the Fermi surface topology and corresponding band calculations.
大貫 惇睦; 摂待 力生*; 杉山 清寛*; 竹内 徹也*; 本多 史憲*; 芳賀 芳範; 山本 悦嗣; 松田 達磨; 立岩 尚之; 青木 大*; et al.
Journal of the Korean Physical Society, 63(3), p.409 - 415, 2013/08
Characteristics of heavy fermion and unconventional superconductivity in rare-earth and actinide compounds are clarified by the de Haas-van Alphen experiments. The effect of pressure on the electronic states of CeRhIn, CeIrSi and YbIrZn is studied in magnetic fields. An electronic instability occurs under pressure in these compounds.
三本 啓輔*; 後藤 沙織*; 根本 祐一*; 赤津 光洋*; 後藤 輝孝*; Dung, N. D.*; 松田 達磨; 芳賀 芳範; 竹内 徹也*; 杉山 清寛*; et al.
Journal of Physics; Condensed Matter, 25(29), p.296002_1 - 296002_8, 2013/07
We have investigated quadrupole effects in tetragonal crystals of PrCuSi and DyCuSi by means of low-temperature ultrasonic measurements. The elastic constant C of PrCuSi exhibits pronounced softening below 70 K, which is described in terms of a quadrupole susceptibility for a doublet ground state.
広瀬 雄介*; 吉内 伸吾*; 西村 尚人*; 阪口 準也*; 榎 健太郎*; 岩川 健*; 三浦 泰直*; 杉山 清寛*; 大貫 惇睦; 摂待 力生*; et al.
Journal of the Korean Physical Society, 62(12), p.1858 - 1861, 2013/06
We succeeded in growing single crystals of YbTIn (T: Co, Rh, Ir), YbGa, YbTZn (T: Co, Rh, Ir), etc. The electronic and magnetic properties are clarified by measuring the electrical resistivity, magnetic susceptibility, magnetization, specific heat and de Haas-van Alphen effect.
広瀬 雄介*; 三浦 泰直*; 堤 泰樹*; 吉内 伸吾*; 大家 政洋*; 杉山 清寛*; 竹内 徹也*; 山上 浩志*; 山本 悦嗣; 芳賀 芳範; et al.
Physica Status Solidi (B), 250(3), p.642 - 645, 2013/03
Electronic states of an antiferromagnet UCd and its reference compound ThCd were investigated by means of de Haas-van Alphen (dHvA) effect. From the cyclotron effective mass determined from the dHvA oscillation, the electronic specific heat of UCd was estimated as 100 mJ/Kmol, much smaller than 840 in the previous report. The result suggests that magnetic excitation contributes significantly to the specific heat.
大貫 惇睦; 摂待 力生*; 竹内 徹也*; 杉山 清寛*; 本多 史憲*; 芳賀 芳範; 山本 悦嗣; 松田 達磨; 立岩 尚之; 青木 大*; et al.
Journal of the Physical Society of Japan, 81(Suppl.B), p.SB001_1 - SB001_18, 2012/12
Fermi surface properties in rare earth and actinide compounds such as CeSn, USi, NpGe and PuIn are clarified by the de Haas-van Alphen experiments on the bases of the energy band calculations. The pressure-induced electronic instability including unconventional superconductivity observed in CeRhIn is also discussed.
大貫 惇睦; 安井 慎一*; 松下 昌輝*; 吉内 伸吾*; 大家 政洋*; 広瀬 雄介*; Dung, N. D.*; 本多 史憲*; 竹内 徹也*; 摂待 力生*; et al.
Journal of the Physical Society of Japan, 80(Suppl.A), p.SA003_1 - SA003_6, 2011/12
We studied the Fermi surface properties of YbCuSi and YbCuGe with the tetragonal structure by measuring the de Haas-van Alphen (dHvA) oscillations, together with the energy band calculations. It was clarified that 4f electrons contribute to the Fermi surface of a valence fluctuating compound YbCuSi, but not to that of a divalent compound YbCuGe. We also studied the heavy fermion properties of YbTZn (T: Co, Rh, Ir) with the cubic caged structure. The metamagnetic behavior or an abrupt nonlinear increase of magnetization was observed. By measuring the electrical resistivity under pressure and magnetic field, we clarified that the electronic state close to the quantum critical point is realized in YbIrZn at 5.2 GPa and also YbCoZn at ambient pressure.
杉山 清寛*; 広瀬 雄介*; 榎 健太郎*; 池田 修悟*; 山本 悦嗣; 立岩 尚之; 芳賀 芳範; 木田 孝則*; 萩原 政幸*; 金道 浩一*; et al.
Journal of the Physical Society of Japan, 80(Suppl.A), p.SA104_1 - SA104_3, 2011/07
Magnetic and transport properties under high magnetic field were studied on a magnetic semiconductor -US. Large magnetization reaching 1.75 has been observed at 50 T. At the same time, resistivity decreases drastically from insulating behavior at 0 T to almost metallic characteristics at 50 T. The results are discussed based on the magnetic polaron mechanism.
大貫 惇睦; 安井 慎一*; 吉内 伸吾*; 大家 政洋*; 松下 昌輝*; 広瀬 雄介*; 竹内 徹也*; 本多 史憲*; 摂待 力生*; 杉山 清寛*; et al.
Journal of Physics; Conference Series, 273, p.012013_1 - 012013_4, 2011/02
Metamagnetic behavior of the heavy fermion compound YbIrZn has been studied experimentally. The metamagnetic transition was clearly seen in the bulk magnetization curve. Near the metamagnetic critical field H 100 kOe, the effective mass of conduction electrons exhibits a significant enhancements. It is suggested that the present metamagnetism is related to the magnetic instability around the quantum critical point.
広瀬 雄介*; 西村 尚人*; 本多 史憲*; 杉山 清寛*; 萩原 政幸*; 金道 浩一*; 竹内 徹也*; 山本 悦嗣; 芳賀 芳範; 松浦 直人*; et al.
Journal of the Physical Society of Japan, 80(2), p.024711_1 - 024711_12, 2011/02
Magnetic and superconducting properties of CeRhGe and CePtSI have been investigated by bulk property measurements and neutron scattering experiments. CeRhGe was found to order antiferromagnetically with an ordered moment 1.3 /Ce along the -axis of the orthorhombic unit cell. High pressure resistivity measurements revealed a suppression of the antiferromagnetic transition with increasing pressure and the occurrence of superconductivity near the critical pressure where antiferromagnetism vanishes. Quantum-critical characteristics are expected to these compounds.
立岩 尚之; 池田 修悟*; 芳賀 芳範; 松田 達磨; 山本 悦嗣; 杉山 清寛*; 萩原 政幸*; 金道 浩一*; 大貫 惇睦*
Journal of the Physical Society of Japan, 80(1), p.014706_1 - 014706_8, 2011/01
竹内 徹也*; 安井 慎一*; 戸田 雅敏*; 松下 昌輝*; 吉内 伸吾*; 大家 政洋*; 片山 敬亮*; 広瀬 雄介*; 吉谷 尚久*; 本多 史憲*; et al.
Journal of the Physical Society of Japan, 79(6), p.064609_1 - 064609_15, 2010/06
Metamagnetic behavior of the heavy-fermion compound YbIrZn was studied by magnetization, de Haas-van Alphen effect, magnetoresistance, specific heat, thermal expansion and magnetostriction. Metamagnetic behavior was observed for all the physical properties at low temperatures. It is remarkable that the Fermi surfaces observed in the dHvA effect unchanges across the metamagnetic transition.
中野 泰典*; 本多 史憲*; 竹内 徹也*; 杉山 清寛*; 萩原 政幸*; 金道 浩一*; 山本 悦嗣; 芳賀 芳範; 摂待 力生*; 山上 浩志*; et al.
Journal of the Physical Society of Japan, 79(2), p.024702_1 - 024702_9, 2010/02
Single crystals of new rare-earth compounds CePdAl and PrPdAl were successfully grown. Magnetic property measurements have shown the existence of the crystal-electric-field effect in these compounds with a magnetic ground state for CePdAl and a singlet ground state for PrPdAl. Fermi surfaces were determined for both compounds by the de Haas-van Alphen experiments, revealing a localized nature of -electrons.
吉内 伸吾*; 戸田 雅敏*; 松下 昌輝*; 安井 慎一*; 広瀬 雄介*; 大家 政洋*; 片山 敬亮*; 本多 史憲*; 杉山 清寛*; 萩原 政幸*; et al.
Journal of the Physical Society of Japan, 78(12), p.123711_1 - 123711_4, 2009/12
High-field magnetization and de Haas-van Alphen effect were measured on a heavy fermion compound YbIrZn. Large cyclotron masses ranging from 4 to 27 were detected in the dHvA experiment, and are found to be reduced at magnetic fields higher than 120 kOe. From the present experimental results together with the 4f-itinerant band calculations, the 4f electrons are considered to form heavy fermion state.
池田 修悟*; 酒井 宏典; 立岩 尚之; 松田 達磨; 青木 大*; 本間 佳哉*; 山本 悦嗣; 中村 彰夫; 塩川 佳伸*; 太田 有基*; et al.
Journal of the Physical Society of Japan, 78(11), p.114704_1 - 114704_10, 2009/11
We studied the magnetic properties of a paramagnet -US with the orthorhombic crystal structure by measuring the magnetization, magnetic susceptibility, specific heat and electrical resistivity under magnetic field and pressure. The 5-crystalline electric field (CEF) scheme was determined from the experimental results The insulating resistivity is drastically changed to a metallic one under high pressure 8 GPa similar to that of the semimetallic Ising-type ferromagnet UTeS with the Curie temperature =87 K. From these experimental results, it was concluded that -US is in the vicinity of the ferromagnetic ordering at ambient pressure. The anomalous magnetization was analyzed on the basis of the ferromagnetic cluster and discussed from a viewpoint of the magnetic polaron.
Hieu, N. V.*; 竹内 徹也*; 宍戸 寛明*; 戸野広 智絵*; 山田 勉*; 中島 弘*; 杉山 清寛*; 摂待 力生*; 松田 達磨; 芳賀 芳範; et al.
Journal of the Physical Society of Japan, 76(6), p.064702_1 - 064702_16, 2007/06
A seriese of ternary compounds RRhIn (R: rare earth) has been grown in the single crystalline form by means of the flux method. Most of these compounds order antiferromagnetically at low temperatures, except R = Y, La, Pr and Yb. The magnetic properties are discussed on the basis of the crystalline-field parameters.
Chen, L.-M.; 中島 一久; Hong, W.*; Hua, J. F.*; 亀島 敬; 小瀧 秀行; 杉山 精博*; Wen, X.*; Wu, Y.*; Tang, C.*; et al.
Chinese Optics Letters, 5(S1), p.S133 - S135, 2007/05
Experiments for the laser guiding studies has been carried out with the 30 fs, 100 TW laser pulse interaction with the long slab and discharged capillary of underdense plasma. Formation of extremely long plasma channel with its length 10 times above the Rayleigh length is observed when the laser pulse power is much higher than the critical power for relativistic self-focusing. The long self-guiding channel formation is accompanied by the quasi-monoenergetic electron acceleration with a low transverse emittance and high electric current (10 nC/shot). In order to continuously elongate plasma channel, a 4 cm-scale discharged capillary was used. We successfully demonstrated laser-plasma acceleration of high-quality electron beams up to nearly GeV. Our results exactly verified the prediction of laser-wakefield acceleration through a cm-scale plasma channel in the blowout bubble regime.
奥田 悠介*; 宮内 裕一朗*; 伊田 勇輝*; 武田 勇司*; 戸野広 智絵*; 大槌 泰弘*; 山田 勉*; Nguyen, D.; 松田 達磨; 芳賀 芳範; et al.
Journal of the Physical Society of Japan, 76(4), p.044708_1 - 044708_11, 2007/04