Original Articles |
|
|
|
|
Novel Transitions in Doped Mott-Insulator KxCoO2 |
YANG Hai-Peng;LU Xi-Feng; WEN Hai-Hu |
National Laboratory for Superconductivity, Institute of Physics and Center for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100080 |
|
Cite this article: |
YANG Hai-Peng, LU Xi-Feng, WEN Hai-Hu 2003 Chin. Phys. Lett. 20 729-730 |
|
|
Abstract By measuring the temperature dependence of the magnetic susceptibility, two distinct transitions have been observed in potassium doped cobalt oxide KxCoO2 (x = 0.2-1.0). The transition around 125 K corresponds to a phase transition between a weak ferromagnetic plus a strong superparamagnetic phase (below 125 K) and a superparamagnetic phase (above 125 K). The susceptibility above the Curie point Tc cannot be described by the Curie-Weise law, being consistent with the superparamagnetism. Magnetization-hysteresis-loops have been measured in different temperature regions to uncover the underlying physics. The second transition near 30.8 K shows a strong novelty.
|
Keywords:
74.10.+v
74.20.Mn
75.47.Pq
74.25.Gz
|
|
Published: 01 May 2003
|
|
|
|
|
|
|
Viewed |
|
|
|
Full text
|
|
|
|
|
Abstract
|
|
|
|
|