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110
and 100 oriented REBCO tapesOsamura, Kozo*; Machiya, Shutaro*; Kajiwara, Kentaro*; Kawasaki, Takuro; Harjo, S.; Zhang, Y.*; Fujita, Shinji*; Iijima, Yasuhiro*; Hampshire, D. P.*
AIP Advances (Internet), 9(7), p.075216_1 - 075216_11, 2019/07
Times Cited Count：7 Percentile：37.59(Nanoscience & Nanotechnology)
; A 
Ge-nuclear-quadrupole-resonance study under pressureHarada, Atsushi*; Kawasaki, Shinji*; Mukuda, Hidekazu*; Kitaoka, Yoshio*; Haga, Yoshinori; Yamamoto, Etsuji; Onuki, Yoshichika; Ito, Kohei*; Haller, E. E.*; Harima, Hisatomo*
Physical Review B, 75(14), p.140502_1 - 140502_4, 2007/04
Times Cited Count：28 Percentile：72.24(Materials Science, Multidisciplinary)This paper reports that a different type of superconducting order parameter has been realized in the ferromagnetic states in UGe via Ge-nuclear-quadrupole-resonance experiments performed under pressure. Measurements of the nuclear spin-lattice relaxation rate (1/
) have revealed an unconventional nature of superconductivity such that the up-spin band is gapped with line nodes, but the down-spin band remains gapless at the Fermi level. This result is consistent with that of a ferromagnetic spin-pairing model in which Cooper pairs are formed among ferromagnetically polarized electrons. The present experiment has shed light on the possible origin of ferromagnetic superconductivity, which is mediated by ferromagnetic spin-density fluctuations relevant to the first-order transition inside the ferromagnetic states.
; Ge-NQR study under pressureHarada, Atsushi*; Kawasaki, Shinji*; Mukuda, Hidekazu*; Kitaoka, Yoshio*; Haga, Yoshinori; Yamamoto, Etsuji; Onuki, Yoshichika; Ito, Kohei*; Haller, E. E.*; Harima, Hisatomo*
Physica B; Condensed Matter, 378-380, p.963 - 964, 2006/05
Times Cited Count：1 Percentile：6.64(Physics, Condensed Matter)The superconducting characteristics on the itinerant ferromagnetic superconductor UGe have been investigated via the Ge-NQR measurements under pressure (
) near the critical pressure 
where the first-order transition takes place from the low-temperature () and low- ferromagnetic phase (FM2) to high- and high- one (FM1). The measurements of nuclear spin-lattice relaxation rate 
have revealed a power-law like behavior as 
without the coherence peak, whereas at low temperatures, it deviates from the dependence to a -linear like behavior. These results that depend on the pressure are well understood in terms of non-unitary spin-triplet pairing state where the ferromagnetic up-spin band is gapped, but the down-spin band remains gapless at the Fermi level. We will argue an intimate relationship of the onset of SC with FM1 and FM2.
In-NQR study of antiferromagnetism and superconductivity in CeRhIn
and CeIn
under pressureKawasaki, Shinji*; Yashima, Mitsuharu*; Kotegawa, Yu*; Mito, Takeshi*; Kawasaki, Yu*; Zheng, G.-Q.*; Kitaoka, Yoshio*; Shishido, Hiroaki*; Araki, Shingo*; Aoki, Dai*; et al.
Journal of Physics and Chemistry of Solids, 67(1-3), p.497 - 499, 2006/01
Times Cited Count：2 Percentile：13.65(Chemistry, Multidisciplinary)We report the novel phase diagram of superconductivity (SC) and antiferromagnetism (AFM) in heavy-fermion (HF) pressure ()-induced superconductors CeRhIn and CeIn through nuclear-quadrupole-resonance (NQR) measurements under . The -induced superconductivity in CeRhIn coexists with AFM on a microscopic level in 1.5-1.9 GPa. By contrast, in CeIn, the -induced phase separation of AFM and paramagnetism (PM) takes place without any trace of a quantum phase transition. The outstanding finding is that SC sets in at both the phasesmagnetically separated into AFM and PM in 2.28-2.5 GPa.
; A Ge-NQR study under pressureHarada, Atsuyuki*; Kawasaki, Shinji*; Kotegawa, Hisashi*; Kitaoka, Yoshio*; Haga, Yoshinori; Yamamoto, Etsuji; Onuki, Yoshichika; Ito, Kohei*; Haller, E. E.*; Harima, Hisatomo*
Journal of the Physical Society of Japan, 74(10), p.2675 - 2678, 2005/10
Times Cited Count：20 Percentile：68.65(Physics, Multidisciplinary)no abstracts in English
Nakamura, Kazuo*; Matsufuji, Shinji*; Tomoda, Seiji*; Wang, F.*; Mitarai, Osamu*; Kurihara, Kenichi; Kawamata, Yoichi; Sueoka, Michiharu; Sato, Konosuke*; Zushi, Hideki*; et al.
no journal, ,
no abstracts in English
Nakamura, Kazuo*; Matsufuji, Shinji*; Tomoda, Seiji*; Wang, F.*; Mitarai, Osamu*; Kurihara, Kenichi; Kawamata, Yoichi; Sueoka, Michiharu; Sato, Konosuke*; Zushi, Hideki*; et al.
no journal, ,
no abstracts in English
Nakamura, Kazuo*; Matsufuji, Shinji*; Tomoda, Seiji*; Wang, F.*; Mitarai, Osamu*; Kurihara, Kenichi; Kawamata, Yoichi; Sueoka, Michiharu; Sato, Konosuke*; Zushi, Hideki*; et al.
no journal, ,
no abstracts in English
Nakamura, Kazuo*; Matsufuji, Shinji*; Tomoda, Seiji*; Wang, F.*; Mitarai, Osamu*; Kurihara, Kenichi; Kawamata, Yoichi; Sueoka, Michiharu; Hasegawa, Makoto*; Tokunaga, Kazutoshi*; et al.
no journal, ,
no abstracts in English
Takahashi, Yoshikazu; Nabara, Yoshihiro; Nunoya, Yoshihiko; Suwa, Tomone; Tsutsumi, Fumiaki; Oshikiri, Masayuki; Ozeki, Hidemasa; Shibutani, Kazuyuki*; Kawano, Katsumi; Kawasaki, Tsutomu*; et al.
no journal, ,
Japan Atomic Energy Agency (JAEA) is procuring all amounts of Nb
Sn conductors for Central Solenoid (CS) in the ITER project. Before start of mass-productions, the conductor should be tested to confirm superconducting performance in the SULTAN facility, Switzerland. The cable with a shorter twist pitch shows no degradation of Tcs against to electromagnetic load cycles. However, it is difficult to make the cable, because the diameter of the cable with shorter twist pitch is larger and the cable has to compact more. The technology for the cables with STP was developed in Japanese cabling suppliers. The several key technologies and production will be described in this paper.
Izumi, Keisuke*; Iguchi, Masayuki*; Iida, Shinji*; Kawasaki, Masaji*; Okawa, Yoshinao*; Oka, Kiyoshi; Yamagata, Ryohei
no journal, ,
no abstracts in English
Tsubota, Yoichi; Honda, Fumiya; Nakagawa, Takahiro; Kawasaki, Takashi; Ikeda, Atsushi; Tamakuma, Yuki*; Tokonami, Shinji*; Momose, Takumaro
no journal, ,
A large number of radioactive aerosols, especially alpha particles, are expected to be generated during fuel debris retrieval on Fukushima - Daiichi (1F) site and decommissioning of nuclear fuel cycle facilities. For conventional alpha dust monitor, 1-channel of silicon surface barrier detector (SSBD) is often used as a detector which has not so high limit of count rates. Moreover, since radioactive aerosol collected on a filter paper are measured by a detector, it is difficult to calculate an airborne concentration at the sampling site because a conventional dust monitor measures an integrated radioactivity on a filter paper. In this work, we developed a prototype of alpha dust monitor aiming at an in-situ measurement of high concentration airborne alpha particles. The efficiency for UO
checking source was 80.8%. For high count rate test using 3 MBq of 
Am checking source, 2.1 
10
cpm was achieved which was more than 10 times higher compared to an conventional alpha dust monitor using SSBD. For follow-up test to the airborne concentration of alpha particles using radon chamber, counting rate of prototype alpha dust monitor was smoothly followed with respect to the radon concentration in a radon chamber.
Tsubota, Yoichi; Honda, Fumiya; Nakagawa, Takahiro; Kawasaki, Takashi; Tamakuma, Yuki*; Tokonami, Shinji*; Momose, Takumaro
no journal, ,
A large number of radioactive aerosols, especially alpha particles, are expected to be generated during fuel debris retrieval on Fukushima - Daiichi (1F) site and decommissioning of nuclear fuel cycle facilities. In the case of conventional alpha dust monitor, silicon surface barrier detector (SSBD) is often used as a detector which has not so high limit of count rates. Moreover, SSBD is not suitable for high humidity environment. In this work, we developed a prototype of alpha dust monitor aiming at an in-situ measurement of high concentration of airborne alpha particles. Approx. 20M cpm of counting rate was achieved which was more than 10 times higher compared to a conventional alpha dust monitor using SSBD. For follow-up test, counting rate of prototype alpha dust monitor was smoothly followed with respect to the airborne concentration of alpha particles.
Tsubota, Yoichi; Yoshida, Masato; Honda, Fumiya; Tokonami, Shinji*; Nakagawa, Takahiro; Kawasaki, Takashi
no journal, ,
In order to measure the airborne concentration in air in real time, a dust monitor to measure directly the alpha-particle concentration in a flat-type flow path was developed and its performance was evaluated. The performance of the prototype dust monitor was evaluated in a high-humidity environment, and its counting rate was more than ten times higher than that of a conventional dust monitor.
Sato, Naomi; Hayano, Akira; Teshima, Minoru*; Negi, Tateyuki*; Yamane, Terumasa*; Kawasaki, Shinji*
no journal, ,
This paper reports the preliminary results of the magnetotelluric (MT) survey aiming to evaluate the three-dimensional distribution of fossil seawater in the Horonobe area. The MT survey was conducted in the area of 3 km square adjacent to the Horonobe Underground Research Laboratory at 60 points. Our results showed that the distribution of the resistivity varied in accordance with the geological structure. This survey was funded by the Ministry of Environment, Trade and Industry.
