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Interplay between mesoscopic phase separation and bulk magnetism in the layered NaxCoO2

A. Zorkovska·M. Orendac·J. Sebek·E. Santava·P. Svoboda·I. Bradaric·I. Savic·A. Feher
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Abstract

Specific heat of the layered NaxCoO2 (x=0.65, 0.70 and 0.75) oxides has been measured in the temperature range of 3-360 K and magnetic field of 0 and 9 T. The analysis of data, assuming the combined effect of inter-layer superexchange and the phase separation into mesoscopic magnetic domains with localized spins embedded in a matrix with itinerant electronic character, suggests that the dominant contribution to the specific heat in the region of short-range ordering is mediated by quasi-2D antiferromagnetic clusters, perpendicular to the CoO2 layers.

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A. Zorkovska, M. Orendac, J. Sebek, E. Santava, P. Svoboda, I. Bradaric, I. Savic, A. Feher. 2005-09-26. Interplay between mesoscopic phase separation and bulk magnetism in the layered NaxCoO2. https://doi.org/10.1103/physrevb.72.132412

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