Multipole correlations of -orbital Hubbard model with spin-orbit coupling

Onishi, Hiroaki

Journal of the Physical Society of Japan, 80(Suppl.A), p.SA141_1 - SA141_3, 2011/07

https://doi.org/10.1143/JPSJS.80SA.SA141

Dilute La-substitutions in CeRhIn studied by means of NMR/NQR techniques

Sakai, Hironori; Kurita, Nobuyuki*; Miclea, C. F.*; Movshovich, R.*; Lee, H.-O.*; Ronning, F.*; Bauer, E. D.*; Thompson, J. D.*

Journal of the Physical Society of Japan, 80(Suppl.A), p.SA059_1 - SA059_3, 2011/07

http://jpsj.ipap.jp/link?JPSJS/80SA/SA059/

The effect of dilute La substitution in CeLaRhIn (0x0.07) has been investigated microscopically by nuclear magnetic/quadrupole resonance (NMR/NQR). By the dilute La substitutions, the 4 lines for In(1) sites are found to be undisturbed and to have a reasonably narrow width, even in the ordered AF state. These 4 positions in the La-substituted CeRhIn indicate a decrease of the internal field on In(1) sites, due to the reduction of hyperfine couplings by La substitutions. The spin-lattice relaxation rates () using these 4 lines at high temperatures can be understood by the reduction of exchange energy and effective moments. On the other hand, in the AF ordered state can be explained by a gapped Fermi surface and spin fluctuations of uncompensated localized Ce moments near the La ions.

Non-magnetic to magnetic transition under high pressure in narrow-gap semiconductor -US

Tateiwa, Naoyuki; Haga, Yoshinori; Sakai, Hironori; Ikeda, Shugo*; Matsuda, Tatsuma; Yamamoto, Etsuji; Onuki, Yoshichika*

Journal of the Physical Society of Japan, 80(Suppl.A), p.SA103_1 - SA103_3, 2011/07

https://doi.org/10.1143/JPSJS.80SA.SA103

We have measured the magnetization of an uranium chalcogenide compound -US under high pressure by piston cylinder and indenter type cells up to 2.42 GPa in a commercial SQUID magnetometer. The compound is a narrow-gap semiconductor that does not order magnetically down to 0.3 K at 1 bar. In this study, it was found that a ferromagnetic state is induced above 1 GPa. The pressure phase diagram were obtained. The values of the spontaneous magnetic moment at 0 K are less than 0.1 , suggesting that the pressure-induced phase is a very weak ferromagnetic state. Considering the CEF singlet ground state in -US, it is suggest that the ferromagnetic state is an "induced-magnetic phase" often observed in some praseodymium compounds such as PrTl. The experimental results are discussed in terms of the mean field theory.

Ultrasonic measurements on the cage-structured clathrate compound UPdSi

Yanagisawa, Tatsuya*; Tateiwa, Naoyuki; Mayama, Taichi*; Saito, Hitoshi*; Hidaka, Hiroyuki*; Amitsuka, Hiroshi*; Haga, Yoshinori; Nemoto, Yuichi*; Goto, Terutaka*

Journal of the Physical Society of Japan, 80(Suppl.A), p.SA105_1 - SA105_3, 2011/07

https://doi.org/10.1143/JPSJS.80SA.SA105

Detailed characterization of U-Co binary compounds

Matsuda, Tatsuma; Sugai, Takashi; Haga, Yoshinori; Yamamoto, Etsuji; Onuki, Yoshichika

Journal of the Physical Society of Japan, 80(Suppl.A), p.SA101_1 - SA101_3, 2011/07

https://doi.org/10.1143/JPSJS.80SA.SA101

Possible long-periodic magnetic structure in SmPb

Ito, Takashi; Higemoto, Wataru; Ninomiya, Kazuhiko; Amato, A.*; Sugai, Takashi; Haga, Yoshinori; Suzuki, Hiroyuki*

Journal of the Physical Society of Japan, 80(Suppl.A), p.SA075_1 - SA075_3, 2011/07

http://jpsj.ipap.jp/link?JPSJS/80SA/SA075/

A series of cubic SmX (X=In, Sn, Pb) compounds has a crystalline-electric-field ground state with various multipolar degrees of freedom. These show phase transitions at low temperatures and a possibility of multipolar ordering has been suggested. However, no microscopic experimental data is available so far and details of the ordered states have not been clarified yet. We performed muon spin relaxation measurements in order to elucidate nature of multipoles in these systems. A breaking of time-reversal symmetry was observed in all the ordered phases in zero applied field, indicating the primary order parameters are magnetic. We also obtained information about the ordered structures from a microscopic point of view.

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

Temperature dependence of soft X-ray photoemission spectra for YbCuSi

Yasui, Akira; Fujimori, Shinichi; Kawasaki, Ikuto; Okane, Tetsuo; Takeda, Yukiharu; Saito, Yuji; Yamagami, Hiroshi; Sekiyama, Akira*; Settai, Rikio*; Matsuda, Tatsuma; et al.

no journal, , 

YbCuSi is one of valence fluctuating compounds. Though there are a few temperature ()-dependent photoemission spectroscopy (PES) measurements for YbCuSi, there are different interpretations of the obtained spectra with each other. The previous studies were performed by using the vacuum ultraviolet (VUV) radiation. The VUV-PES spectra have considerably large contribution of the surface state. In order to examine the bulk electronic state in detail, it is needed to suppress the surface contribution. The soft X-ray PES (SX-PES) is a powerful tool to investigate the bulk electronic state. The SX-PES measurements were performed at BL23SU in SPring-8. In our SX-PES spectra, the surface Yb 4 contribution is very small. With increasing , the bulk Yb 4 peaks shift toward the higher energy side, while the Yb multiplets do not move. Since the energy shift cannot be explained in the single impurity Anderson model, the experimental results indicate the Kondo lattice effects play important roles for YbCuSi.

Resonant X-ray diffraction study of multipole ordering in CePdS

Michimura, Shinji; Inami, Toshiya; Matsuoka, Eiichi*; Watahiki, Masanori*; Onodera, Hideya*

no journal, ,