Charge-ordering, commensurability and metallicity in the phase diagram of layered Na(x)CoO(2)

Maw Lin Foo; Yayu Wang; Satoshi Watauchi; H. W. Zandbergen; Tao He; R. J. Cava; N. P. Ong

doi:10.1103/physrevlett.92.247001

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Charge-ordering, commensurability and metallicity in the phase diagram of layered Na(x)CoO(2)

Maw Lin Foo·Yayu Wang·Satoshi Watauchi·H. W. Zandbergen·Tao He·R. J. Cava·N. P. Ong

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Abstract

The phase diagram of non-hydrated Na(x)CoO(2) has been determined by changing the Na content x using a series of chemical reactions. As x increases from 0.3, the ground state goes from a paramagnetic metal to a charge-ordered insulator (at x=1/2) to a `Curie-Weiss metal' (around 0.70), and finally to a weak-moment magnetically ordered state (x>0.75). The unusual properties of the state at 1/2 (including particle-hole symmetry at low T and enhanced thermal conductivity) are described. The strong coupling between the Na ions and the holes is emphasized.

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Maw Lin Foo, Yayu Wang, Satoshi Watauchi, H. W. Zandbergen, Tao He, R. J. Cava, N. P. Ong. 2004-02-26. Charge-ordering, commensurability and metallicity in the phase diagram of layered Na(x)CoO(2). https://doi.org/10.1103/physrevlett.92.247001

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