Field-induced insulator-metal transition in EuTe

Takeuchi, Tetsuya*; Honda, Fuminori*; Aoki, Dai*; Haga, Yoshinori; Kida, Takanori*; Narumi, Yasuo*; Hagiwara, Masayuki*; Kindo, Koichi*; Karube, Kosuke*; Harima, Hisatomo*; et al.

Journal of the Physical Society of Japan, 93(4), p.044708_1 - 044708_10, 2024/04

https://doi.org/10.7566/JPSJ.93.044708

Magnetic properties of single crystalline TbSb

Kitaori, Aki*; Kanazawa, Naoya*; Kida, Takanori*; Narumi, Yasuo*; Hagiwara, Masayuki*; Kindo, Koichi*; Takeuchi, Tetsuya*; Nakamura, Ai*; Aoki, Dai*; Haga, Yoshinori; et al.

Journal of the Physical Society of Japan, 92(2), p.024702_1 - 024702_6, 2023/02

https://doi.org/10.7566/JPSJ.92.024702

Magnetic-field-induced metallic state in -US

Sugiyama, Kiyohiro*; Hirose, Yusuke*; Enoki, Kentaro*; Ikeda, Shugo*; Yamamoto, Etsuji; Tateiwa, Naoyuki; Haga, Yoshinori; Kida, Takanori*; Hagiwara, Masayuki*; Kindo, Koichi*; et al.

Journal of the Physical Society of Japan, 80(Suppl.A), p.SA104_1 - SA104_3, 2011/07

https://doi.org/10.1143/JPSJS.80SA.SA104

Magnetic field and pressure phase diagrams of uranium heavy-fermion compound UZn

Tateiwa, Naoyuki; Ikeda, Shugo*; Haga, Yoshinori; Matsuda, Tatsuma; Yamamoto, Etsuji; Sugiyama, Kiyohiro*; Hagiwara, Masayuki*; Kindo, Koichi*; Onuki, Yoshichika*

Journal of the Physical Society of Japan, 80(1), p.014706_1 - 014706_8, 2011/01

https://doi.org/10.1143/JPSJ.80.014706

We have performed the magnetization measurements in high magnetic fields up to 53 T on single crystals of an uranium heavy fermion compound UZn. In the antiferromagnetic state below the Nel temperature = 9.7 K, a metamagnetic transition is found at 32 T for the field along the [110] direction (-axis). The magnetic phase diagram for the field along the [110] direction is given. We have also carried out high pressure resistivity measurement on UZn using a diamond anvil cell up to 8.7 GPa. The Nel temperature is almost pressure-independent up to 4.7 GPa and starts to increase at the higher pressure region. The pressure dependences of the coefficient of term in the electrical resistivity , an antiferromagnetic gap and a characteristic temperature are discussed.

Magnetic and Fermi surface properties of CePdAl and PrPdAl

Nakano, Yasunori*; Honda, Fuminori*; Takeuchi, Tetsuya*; Sugiyama, Kiyohiro*; Hagiwara, Masayuki*; Kindo, Koichi*; Yamamoto, Etsuji; Haga, Yoshinori; Settai, Rikio*; Yamagami, Hiroshi*; et al.

Journal of the Physical Society of Japan, 79(2), p.024702_1 - 024702_9, 2010/02

https://doi.org/10.1143/JPSJ.79.024702

Possible existence of magnetic polaron in nearly ferromagnetic semiconductor -US

Ikeda, Shugo*; Sakai, Hironori; Tateiwa, Naoyuki; Matsuda, Tatsuma; Aoki, Dai*; Homma, Yoshiya*; Yamamoto, Etsuji; Nakamura, Akio; Shiokawa, Yoshinobu*; Ota, Yuki*; et al.

Journal of the Physical Society of Japan, 78(11), p.114704_1 - 114704_10, 2009/11

https://doi.org/10.1143/JPSJ.78.114704

Beam acceleration with full-digital LLRF control system in the J-PARC RCS

Tamura, Fumihiko; Schnase, A.; Nomura, Masahiro; Yamamoto, Masanobu; Hasegawa, Katsushi; Haga, Koichi; Yoshii, Masahito*; Omori, Chihiro*; Toda, Makoto*; Hara, Keigo*; et al.

Proceedings of 11th European Particle Accelerator Conference (EPAC '08) (CD-ROM), p.364 - 366, 2008/06

http://accelconf.web.cern.ch/AccelConf/e08/papers/mopc126.pdf

In the J-PARC RCS (Rapid Cycling Synchrotron) we employ a full-digital LLRF control system to accelerate an ultra-high intensity proton beam. The key feature is the multi-harmonic RF signal generation by using direct digital synthesis (DDS) technology. By employing a full-digital system, highly accurate, stable and reproductive RF voltages are generated in the wide-band RF cavities loaded by magneticalloy (MA) cores. The beam commissioning of the J-PARC RCS has been started in October 2007. The accelerators, the linac and the RCS, show good stability. The beam orbit and the longitudinal beam shape and phase are reproductive from cycle to cycle especially thanks to the stability of the linac energy, the RCS bending field and the frequency and voltage of the RCS RF. This reproductivity makes the beam commissioning efficient. We present the examples of the orbit signals and the longitudinal currentsignals. Also, we discuss the longitudinal beam control performance and future plans.

Development of MA core for J-PARC Ring RF Cavity

Nomura, Masahiro; Tamura, Fumihiko; Schnase, A.; Yamamoto, Masanobu; Hasegawa, Katsushi; Shimada, Taihei; Suzuki, Hiromitsu; Ezura, Eiji*; Hara, Keigo*; Toda, Makoto*; et al.

Proceedings of 5th Annual Meeting of Particle Accelerator Society of Japan and 33rd Linear Accelerator Meeting in Japan (CD-ROM), p.246 - 248, 2008/00

http://www.pasj.jp/web_publish/pasj5_lam33/contents/PDF/FO/FO30.pdf

We have been developing MA core for J-PARC Ring RF Cavity. From long run tests, we found that poor electrical isolation between layers caused damages to the cores. We improved the electrical isolation mainly by introducing a smooth tension control system to the winding process. The degree of the each core's electrical isolation was evaluated by the results of DC resistance and radial RF impedance measurements. After long run tests of all of the cores, we installed 10 RF cavities in a tunnel in May 2007 and beam commissioning was started from October 2007. Until now, total operation time of the RF cavities in the tunnel is about 1500 hours. To check the condition of the cores, we measured the RF cavity impedance at intervals of beam operations. The result of impedance measurements shows that no impedance reduction related to core damage was observed.

Magnetic and superconducting properties of LaIrSi and CeIrSi with the non-centrosymmetric crystal structure

Okuda, Yusuke*; Miyauchi, Yuichiro*; Ida, Yuki*; Takeda, Yuji*; Tonohiro, Chie*; Ozuchi, Yasuhiro*; Yamada, Tsutomu*; Nguyen, D.; Matsuda, Tatsuma; Haga, Yoshinori; et al.

Journal of the Physical Society of Japan, 76(4), p.044708_1 - 044708_11, 2007/04

https://doi.org/10.1143/JPSJ.76.044708

Single crystals of LaIrSi and CeIrSi were grown by the Czochralski pulling method in a tetra-arc furnace and the magnetic and superconducting properties, together with super- conductivity in CeIrCoSi, were clarified by measuring the electrical resistivity, specific heat, magnetic susceptibility, magnetization and de Haas-van Alphen (dHvA) effect. From the results of the dHvA experiment for LaIrSi, the Fermi surface is found to split into two Fermi surfaces due to the spin-orbit interaction arising from the non-centrosymmetric crystal structure. The electronic state of CeIrSi is tuned from the antiferro- magnetic state to the superconducting state by applying pressure. The upper critical field H(0) at a pressure of 2.65 GPa is found to be highly anisotropic. Large magnitude and anisotropy of H(0) in CeIrSi are consistent with the theoretical prediction for superconductivity in the non-centrosymmetric crystal structure.

Single crystal growth and magnetic properties of antiferromagnet CePdSi

Nguyen, D.; Haga, Yoshinori; Matsuda, Tatsuma; Yamada, Tsutomu*; Thamizhavel, A.*; Okuda, Yusuke*; Takeuchi, Tetsuya*; Sugiyama, Kiyohiro*; Hagiwara, Masayuki*; Kindo, Koichi*; et al.

Journal of the Physical Society of Japan, 76(2), p.024702_1 - 024702_6, 2007/02

https://doi.org/10.1143/JPSJ.76.024702

We succeeded in growing a single crystal of CePdSi with the orthorhombic crystal structure by the Sn-flux method and measured the electrical resistivity, specific heat, magnetic susceptibility and magnetization. The antiferromagnetic ordering was confirmed to be = 7.2 K. The electronic specific heat coefficient was determined as 77 mJ/KmolCe. The antiferromagnetic easy-axis was found to be the [001] direction, with an ordered moment of = 1.3 /Ce, while [100] and [010] directions are hard-axes in magnetization. We observed a metamagnetic transition at 5.7 T for [001] and a saturation of magnetization above 12.1 T. The characteristic magnetic phase diagram was constructed. The crystalline electric field (CEF) scheme was proposed for CePdSi, where the splitting energies between the ground state and two excited doublets in the CEF scheme are estimated to be 87 K and 504 K, respectively.