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arXiv · 0710.4341

Pressure effects in the triangular layered cobaltites NaxCoO2

G. Garbarino·M. Monteverde·M. Nunez Regueiro·C. Acha·M. L. Foo·R. J. Cava
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Abstract

We have measured transport properties as a function of temperature and pressure up to 30GPa in the NaxCoO2 system. For the x=0.5 sample the transition temperature at 53K increases with pressure, while paradoxically the sample passes from an insulating to a metallic ground state. A similar transition is observed in the x=0.31 sample under pressure. Compression on the x=0.75 sample transforms the sample from a metallic to an insulating state. We discuss our results in terms of interactions between band structure effects and Na+ order.

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G. Garbarino, M. Monteverde, M. Nunez Regueiro, C. Acha, M. L. Foo, R. J. Cava. 2007-10-23. Pressure effects in the triangular layered cobaltites NaxCoO2. https://doi.org/10.1103/physrevb.77.064105

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