Tajima, Hiroyuki, Yoshida, Gosuke, Matsuda, Masaki, Yamaura, Jun-Ichi, Hanasaki, Noriaki, Naito, Toshio, ...
Magnetic torque (3≤T≤46 K), dc magnetic susceptibility (2≤T≤300 K), and ac magnetic susceptibility (2≤T≤30 K) are reported for PTMA0.5[Fe(Pc)(CN)2]･CH3CN. The torque curves exhibit a...
Rattling-Induced Superconductiviy in the Beta-Pyrochlore Oxides AOs2O6 (2009)
Nagao, Yohei, Yamaura, Jun-ichi, Ogusu, Hiroki, Okamoto, Yoshihiko, Hiroi, Zenji
The superconducting properties of two beta-pyrochlore oxides, CsOs2O6 and RbOs2O6, are studied by thermodynamic and transport measurements using high-quality single crystals. It is shown that the...
Unique Phase Transition on Spin-2 Triangular Lattice of Ag2MnO2 (2008)
Yoshida, Hiroyuki, Ahlert, Sascha, Jansen, Martin, Okamoto, Yoshihiko, Yamaura, Jun-Ichi, Hiroi, Zenji
Ag2MnO2 is studied as a possible candidate compound for an antiferromagnetic XY spin model on a triangular lattice. In spite of the large Curie-Weiss temperature of -430 K found in magnetic...
Precise Control of Band Filling in NaxCoO2 (2007)
Yoshizumi, Daisuke, Muraoka, Yuji, Okamoto, Yoshihiko, Kiuchi, Yoko, Yamaura, Jun-Ichi, Mochizuki, Masahito, ...
Electronic properties of the sodium cobaltate NaxCoO2 are systematically studied through a precise control of band filling. Resistivity, magnetic susceptibility and specific heat measurements are...
Chemical trends of superconducting properties in pyrochlore oxides (2006)
Hiroi, Zenji, Yamaura, Jun-Ichi, Yonezawa, Shigeki, Harima, Hisatomo
Chemical trends of fundamental superconducting parameters and normal-state properties are described for a family of pyrochlore oxide superconductors. Particularly, the change of Tc from 1.0 K for...
Crystal structure of the pyrochlore oxide superconductor KOs$_2$O$_6$ (2005)
Yamaura, Jun-Ichi, Yonezawa, Shigeki, Muraoka, Yuji, Hiroi, Zenji
We report the single-crystal X-ray analysis of the structure of the pyrochlore oxide superconductor KOs$_2$O$_6$. The structure was identified as the $\beta$-pyrochlore structure with space group...
Erratum to Three Papers on the beta-Pyrochlore Oxide Superconductors (2005)
Hiroi, Zenji, Yonezawa, Shigeki, Yamaura, Jun-Ichi, Muramatsu, Takaki, Matsushita, Yoshitaka, Muraoka, Yuji
The magnitude of magnetic fields given in the three papers that report on the superconductivity of the beta-pyrochlore oxides is corrected.
Second Anomaly in the Specific Heat of beta-Pyrochlore Oxide Superconductor KOs2O6 (2005)
Hiroi, Zenji, Yonezawa, Shigeki, Yamaura, Jun-Ichi, Muramatsu, Takaki, Muraoka, Yuji
Resistivity and specific heat have been measured on a single crystalline sample of the beta-pyrochlore oxide superconductor, KOs2O6. It is found that a second peak in specific heat, which may...
Specific Heat of the beta-Pyrochlore Oxide Superconductors CsOs2O6 and RbOs2O6 (2005)
Hiroi, Zenji, Yonezawa, Shigeki, Muramatsu, Takaki, Yamaura, Jun-Ichi, Muraoka, Yuji
Two beta-pyrochlore oxide superconductors, CsOs2O6 and RbOs2O6, are studied thermodynamically by measuring specific heat on polycrystalline samples. It is found that a Sommerfeld coefficient ? is...
Low Temperature Symmetry of Pyrochlore Oxide Cd2Re2O7 (2002)
Yamaura, Jun-Ichi, Hiroi, Zenji
We report the X-ray study for the pyrochlore oxide Cd2Re2O7. Two symmetry-lowering structural transitions were observed at Ts1=200K and Ts2=120K. The former is of the second order from the ideal...
The second phase transition in the pyrochlore oxide Cd2Re2O7 (2002)
Hiroi, Zenji, Yamaura, Jun-Ichi, Muraoka, Yuji, Hanawa, Masafumi
Evidence for another phase transition at 120 K in the metallic pyrochlore oxide Cd2Re2O7, following the structural transition at 200 K and followed by the superconducting transition at 1.0 K, is...