|
|
Hokkaido University Collection of Scholarly and Academic Papers >
Graduate School of Engineering / Faculty of Engineering >
Peer-reviewed Journal Articles, etc >
Electronic phase diagram of the layered cobalt oxide system LixCoO2 (0.0 ≤ x ≤ 1.0)
| Title: | Electronic phase diagram of the layered cobalt oxide system LixCoO2 (0.0 ≤ x ≤ 1.0) |
| Authors: | Motohashi, T. Browse this author →KAKEN DB | | Ono, T. Browse this author | | Sugimoto, Y. Browse this author | | Masubuchi, Y. Browse this author | | Kikkawa, S. Browse this author | | Kanno, R. Browse this author | | Karppinen, M. Browse this author | | Yamauchi, H. Browse this author |
| Keywords: | antiferromagnetic materials | | charge-ordered states | | electron correlations | | lithium compounds | | magnetic susceptibility | | magnetic transitions | | nuclear quadrupole resonance | | paramagnetism |
| Issue Date: | Oct-2009 |
| Publisher: | American Physical Society |
| Journal Title: | Physical Review B |
| Volume: | 80 |
| Issue: | 16 |
| Start Page: | 165114 |
| Publisher DOI: | 10.1103/PhysRevB.80.165114 |
| Abstract: | Here we report the magnetic properties of the layered cobalt oxide system, LixCoO2, in the whole range of Li composition, 0 ≤ x ≤ 1. Based on dc-magnetic-susceptibility data, combined with results of Co-59 nuclear magnetic resonance (NMR) and nuclear quadrupole resonance (NQR) observations, the electronic phase diagram of LixCoO2 has been established. As in the related material NaxCoO2, a magnetic critical point is found to exist between x=0.35 and 0.40, which separates the Pauli-paramagnetic and Curie-Weiss metals. In the Pauli-paramagnetic regime (x ≤ 0.35), the antiferromagnetic spin correlations systematically increase with decreasing x. Nevertheless, CoO2, the x=0 end member is a noncorrelated metal in the whole temperature range studied. In the Curie-Weiss regime (x ≥ 0.40), on the other hand, various phase transitions are observed. For x=0.40, a susceptibility hump is seen at 30 K, suggesting the onset of static antiferromagnetic order. A magnetic jump, which is likely to be triggered by charge ordering, is clearly observed at T-t ≈ 175 K in samples with x=0.50 (=1/2) and 0.67 (=2/3), while only a tiny kink appears at T ≈ 210 K in the sample with an intermediate Li composition, x=0.60. Thus, the phase diagram of the LixCoO2 system is complex and the electronic properties are sensitively influenced by the Li content (x). |
| Rights: | © 2009 The American Physical Society |
| Type: | article |
| URI: | http://hdl.handle.net/2115/39844 |
| Appears in Collections: | 工学院・工学研究院 (Graduate School of Engineering / Faculty of Engineering) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)
|
Submitter: 本橋 輝樹
|
