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Revisiting the phase diagram of T*-type La$_{1-x/2}$Eu$_{1-x/2}$Sr$_x$CuO$_4$ using Oxygen $K$-edge X-ray absorption spectroscopy

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 نشر من قبل Masaki Fujita
 تاريخ النشر 2020
  مجال البحث فيزياء
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Oxygen $K$-edge X-ray absorption spectroscopy measurements were conducted on T*-type La$_{1-x/2}$Eu$_{1-x/2}$Sr$_x$CuO$_4$ (LESCO) to estimate the hole density ($n_{rm h}$) and investigate the oxidation annealing effect on $n_{rm h}$. A drastic increase in $n_{rm h}$ due to annealing was found. The increase in $n_{rm h}$ cannot be explained solely by the oxygen gain due to annealing, suggesting that delocalized holes are introduced into the CuO$_2$ plane. A phase diagram of LESCO was redrawn against $n_{rm h}$.



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