Low Temperature Physics: 33, 944 (2007); https://doi.org/10.1063/1.2747070 (4 pages)
Fizika Nizkikh Temperatur: Volume 33, Number 11 (November 2007), p. 1243-1247 ( to contents , go back )
Non-Fermi liquid behavior in the layered NaxCoO2
A. Zorkovská1, J. Šebek2, E. Šantavá2, I. Bradaric3, and A. Feher1
1Centre of Low Temperature Physics of the P. J. Šafárik University & the Slovak Academy of Science 9 Park Angelinum, Košice 04154, Slovakia
2Institute of Physics AS CR, 2 Na Slovance, Prague 18221, Czech Republic
3The «Vinča» Institute of Nuclear Sciences, P.O. Box 522, Belgrade 11001, Serbia
Received April 17, 2007, revised June 22, 2007
The specific heat in the temperature region of 100 mK–360 K and in magnetic fields of 0 and 9 T, as well as the susceptibility from 2 to 360 K and in a magnetic field of 1 T have been measured in the layered NaxCoO2 (x = 0.65, 0.70, and 0.75) oxides. Analysis of the data revealed non-Fermi liquid behavior. The character of the observed anomalies seems to be connected to the mesoscopic phase separation, underlining the impact of disorder on the low-lying excitations in cobaltates.
PACS: 71.27.+a Strongly correlated electron systems; heavy fermions;
Key words: cobaltates, specific heat, non-Fermi liquid behavior, phase separation, magnetic susceptibility.