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

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 نشر من قبل Takashi Imai
 تاريخ النشر 2008
  مجال البحث فيزياء
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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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