Low Temperature Physics: 33, 944 (2007); https://doi.org/10.1063/1.2747070 (4 pages)
Физика Низких Температур: Том 33, Выпуск 11 (Ноябрь 2007), c. 1243-1247    ( к оглавлению , назад )

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

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;
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.