Sakai, Hironori; Chudo, Hiroyuki; Tokunaga, Yo; Kambe, Shinsaku; Haga, Yoshinori; Ronning, F.*; Bauer, E. D.*; Thompson, J. D.*; Homma, Yoshiya*; Aoki, Dai*; et al.
Journal of the Physical Society of Japan, 81(Suppl.B), p.SB003_1 - SB003_6, 2012/12
In the so-called 115 family members with chemical formulae of CeIn (=Co, Rh, Ir) and Ga (=U, Np, Pu), our analysis of the Knight shift and spin-lattice relaxation rates suggests that larger XY-type anisotropy in the antiferromagnetic spin fluctuations in the normal states would favor -wave superconductivity with higher . In order to examine this working hypothesis, the anisotropy ratios of antiferromagnetic fluctuations are derived from our NMR results for the superconductor NpPdAl and antiferromagnet CePdAl, which are tetragonal compounds with a 115-related structure. CePdAl shows Ising-type anisotropy, which is the same anisotropy as in the ordered state. On the other hand, NpPdAl shows XY-type anisotropy just above .
Matsuda, Tatsuma; Tateiwa, Naoyuki; Yamamoto, Etsuji; Haga, Yoshinori; Fisk, Z.
Journal of the Physical Society of Japan, 81(Suppl.B), p.SB037_1 - SB037_4, 2012/12
Haga, Yoshinori; Homma, Yoshiya*; Aoki, Dai*; Nakajima, Kunihisa; Arai, Yasuo; Matsuda, Tatsuma; Ikeda, Shugo*; Sakai, Hironori; Yamamoto, Etsuji; Nakamura, Akio; et al.
Journal of the Physical Society of Japan, 81(Suppl.B), p.SB007_1 - SB007_4, 2012/12
Ito, Takashi; Higemoto, Wataru; Ninomiya, Kazuhiko; Sakai, Akito*; Nakatsuji, Satoru*
Journal of the Physical Society of Japan, 81(Suppl.B), p.SB050_1 - SB050_4, 2012/12
Recently, Al compounds (: rare earth, : transition metal) have attracted much attention due to interesting physical properties closely related to their caged-structure. Each ion is confined in a Frank-Kasper cage consisting of 16 Al atoms and the large coordination number leads to strong - hybridization. In addition, the Frank-Kasper cage allows various multipole degrees of freedom for the -electrons at low because of a highly symmetric crystalline-electric-field (CEF). Among the Al series, PrAl (: Ti, V) and SmAl (: Ti, V, Cr) exhibit both these features. The ground doublet systems PrAl (: Ti, V) show a phase transition at = 2.0K (Ti) and 0.6K (V). The order parameter is believed to be an electric quadrupole active in the subspace. A possibility of the quadrupole Kondo effect has been discussed based on characteristic -dependence in specific heat, resistivity, and magnetic susceptibility. The ground quartet systems SmAl (: Ti, V, Cr) also exhibit a phase transition at = 6.4K (Ti), 2.3K (V), and 1.8K (Cr). A nuclear specific heat study in SmTiAl suggests that the primary order parameter is a magnetic dipole in spite of field-insensitive nature of the phase boundary. A possible importance of a secondarily ordered octupole moment was discussed. We here present a microscopic study of PrTiAl and SmAl (: Ti, V, Cr) using muon spin relaxation. In PrTiAl, no additional local field was observed in the ordered phase. This strongly supports the quadrupole ordering scenario. On the other hand, an appearance of a coherent local field was observed below in SmAl. This is consistent with the primary magnetic dipole ordering. The frequency distribution suggests that the magnetic structure is possibly different between the SmAl compounds.
Kaneko, Koji; Stockert, O.*; Skoulatos, M.*; Schneidewind, A.*; Takeuchi, Tetsuya*; Matsuda, Tatsuma; Haga, Yoshinori; Settai, Rikio*; Onuki, Yoshichika; Metoki, Naoto
Journal of the Physical Society of Japan, 81(Suppl.B), p.SB006_1 - SB006_7, 2012/12
Koyama, Takehide*; Ozaki, Yuzuru*; Ueda, Koichi*; Mito, Takeshi*; Kohara, Takao*; Waki, Takeshi*; Tabata, Yoshikazu*; Michioka, Chishiro*; Yoshimura, Kazuyoshi*; Suzuki, Michito; et al.
Journal of the Physical Society of Japan, 81(Suppl.B), p.SB008_1 - SB008_5, 2012/12
The normal state properties of a noncentrosymmetric superconductor MoAlC are studied by means of the nuclear magnetic resonance (NMR) experiment. The change of NMR line shape and the peak of the nuclear spin-echo decay rate at 130 K indicate that the MoAlC exhibits the phase transition prior to the emergence of superconductivity. The reduction in the conduction electron density is inferred from the decrease in the nuclear spin-lattice relaxation rate. The nature of the newly found phase transition is discussed by considering the result of the first principle calculations, indicating a good nesting property of the Fermi surfaces.
Aoki, Dai*; Taupin, M.*; Paulsen, C.*; Hardy, F.*; Taufour, V.*; Kotegawa, Hisashi*; Hassinger, E.*; Malone, L.*; Matsuda, Tatsuma; Miyake, Atsushi*; et al.
Journal of the Physical Society of Japan, 81(Suppl.B), p.SB002_1 - SB002_6, 2012/12
Sakoda, Masahito*; Kubota, Kazuhiro*; Tanaka, Shuhei*; Matsuoka, Eiichi*; Sugawara, Hitoshi*; Matsuda, Tatsuma; Haga, Yoshinori
Journal of the Physical Society of Japan, 81(Suppl.B), p.SB011_1 - SB011_4, 2012/12
Tsutsumi, Hiroki*; Sakaguchi, Junya*; Miura, Yasunao*; Matsuda, Tatsuma; Haga, Yoshinori; Takeuchi, Tetsuya*; Harima, Hisatomo*; Settai, Rikio*; Onuki, Yoshichika
Journal of the Physical Society of Japan, 81(Suppl.B), p.SB027_1 - SB027_4, 2012/12
Onuki, Yoshichika; Settai, Rikio*; Takeuchi, Tetsuya*; Sugiyama, Kiyohiro*; Honda, Fuminori*; Haga, Yoshinori; Yamamoto, Etsuji; Matsuda, Tatsuma; Tateiwa, Naoyuki; Aoki, Dai*; et al.
Journal of the Physical Society of Japan, 81(Suppl.B), p.SB001_1 - SB001_18, 2012/12
Fujimori, Shinichi; Okochi, Takuo*; Kawasaki, Ikuto; Yasui, Akira; Takeda, Yukiharu; Okane, Tetsuo; Saito, Yuji; Yamagami, Hiroshi; Haga, Yoshinori; Yamamoto, Etsuji; et al.
no journal, ,
Angle resolved photoemission (ARPES) is a powerful experimental technique to study the electronic structure of materials. In particular, recent remarkable progress in ARPES experiments with high energy soft X-ray synchrotron radiation (SX-ARPES) made it possible to directly observe the bulk electronic structure of strongly correlated materials. In the present study, the results on the SX-ARPES on some strongly correlated uranium compounds will be presented.