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
E-mail: anna.zorkovska@upjs.sk
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
pos Анотація:
Received April 17, 2007, revised June 22, 2007
Abstract
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;
PACS: 73.43.Nq Quantum phase transitions;
PACS: 74.20.Mn Nonconventional mechanisms.
Key words: cobaltates, specific heat, non-Fermi liquid behavior, phase separation, magnetic susceptibility.
