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arXiv · 0711.4023

^{59}Co NMR evidence for charge ordering below T_{CO}\sim 51 K in Na_{0.5}CoO_2

F. L. Ning·S. M. Golin·K. Ahilan·T. Imai·G. J. Shu·F. C. Chou
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Abstract

The CoO$_{2}$ layers in sodium-cobaltates Na$_{x}$CoO$_{2}$ may be viewed as a spin $S=1/2$ triangular-lattice doped with charge carriers. The underlying physics of the cobaltates is very similar to that of the high $T_{c}$ cuprates. We will present unequivocal $^{59}$Co NMR evidence that below $T_{CO}\sim51 K$, the insulating ground state of the itinerant antiferromagnet Na$_{0.5}$CoO$_{2}$ ($T_{N}\sim 86 K$) is induced by charge ordering.

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F. L. Ning, S. M. Golin, K. Ahilan, T. Imai, G. J. Shu, F. C. Chou. 2008-01-20. ^{59}Co NMR evidence for charge ordering below T_{CO}\sim 51 K in Na_{0.5}CoO_2. https://doi.org/10.1103/physrevlett.100.086405

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