Metamagnetic transition in Na 0.85 CoO2 single crystals.
We report the magnetization, specific heat, and transport measurements of a high quality Na(0.85)CoO2 single crystal in applied magnetic fields up to 14 T. At high temperatures, the system is in a paramagnetic phase. It undergoes a magnetic phase transition below approximately 20 K. For the field H||c, the measurement data of magnetization, specific heat, and magnetoresistance reveal a metamagnetic transition from an antiferromagnetic state to a quasiferromagnetic state at about 8 T at low temperatures. However, no transition is observed in the magnetization measurements up to 14 T for H perpendicular c. The low temperature magnetic phase diagram of Na(0.85)CoO2 is determined.
Luo
J L
JL
Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China.
Wang
N L
NL
Liu
G T
GT
Wu
D
D
Jing
X N
XN
Hu
F
F
Xiang
T
T