Magnetic anomalies of hydrous cobaltate compound Nax(H3O)zCoO2•yH2O detected by NMR and NQR measurements

被引：1

作者：

Ihara, Y. ^{[1
]}

Takeya, H. ^{[1
]}

Ishida, K. ^{[1
]}

Yoshimura, K. ^{[2
]}

Takada, K. ^{[3
]}

Sasaki, T. ^{[3
]}

Sakurai, H. ^{[4
]}

Takayama-Muromachi, E. ^{[4
]}

机构：

[1] Kyoto Univ, Grad Sch Sci, Dept Phys, Kyoto 6068502, Japan

[2] Kyoto Univ, Grad Sch Sci, Dept Chem, Kyoto 6068502, Japan

[3] Natl Inst Mat Sci, Nanoscale Mat Ctr, Tsukuba, Ibaraki 3050044, Japan

[4] Natl Inst Mat Sci, Adv Nano Mat Lab, Tsukuba, Ibaraki 3050044, Japan

来源：

PHYSICAL REVIEW B | 2009年 / 79卷 / 02期

关键词：

ground states; nuclear quadrupole resonance; phase diagrams; sodium compounds; superconducting materials; superconducting transitions; PHASE-DIAGRAM; UNCONVENTIONAL SUPERCONDUCTIVITY; HEAT-CAPACITY; NAXCOO2-CENTER-DOT-YH(2)O; NA0.3COO2-CENTER-DOT-1.3H(2)O; RELAXATION; ORDER;

D O I：

10.1103/PhysRevB.79.024510

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

In order to investigate the relationship between superconductivity and magnetism in bilayer-hydrate cobaltate Na-x(H3O)(z)CoO2 center dot yH(2)O Co nuclear magnetic resonance (NMR) and nuclear quadrupole resonance (NQR) measurements were performed on three different samples, which demonstrate various ground states at low temperatures. The appearance of small internal fields is observed in the NQR spectra below approximately 6 K on one of the samples that possesses the largest c-axis length and the highest NQR frequency. The other two samples exhibit superconducting transition in zero magnetic field, while these two samples show different ground states in the magnetic fields greater than 5 T. The comparison of the NMR spectra of these two samples obtained in high magnetic fields reveals the appearance of static internal magnetic fields at the Co site below 4 K in the sample that possesses the intermediate c-axis length and the NQR frequency.

引用

页数：10