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arXiv · 2005.11148

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

Shun Asano·Kenji Ishii·Kohei Yamagami·Jun Miyawaki·Yoshihisa Harada·Masaki Fujita
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Abstract

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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Shun Asano, Kenji Ishii, Kohei Yamagami, Jun Miyawaki, Yoshihisa Harada, Masaki Fujita. 2020-05-22. 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. https://doi.org/10.7566/jpsj.89.075002

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