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

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 ($n_{\mathrm{h}}$) and investigate the oxidation annealing effect on $n_{\mathrm{h}}$. A drastic increase in $n_{\mathrm{h}}$ due to annealing was found. The increase in $n_{\mathrm{h}}$ 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 $n_{\mathrm{h}}$.

3 pages, 2 figures

References in corpus (1)

• Oxidation annealing effects on the spin-glass-like magnetism and appearance of superconductivity in T*-type La${}_{1-x/2}$Eu${}_{1-x/2}$Sr${}_x$CuO${}_4$ (0.14 $\le x\le$ 0.28)

Cited by in corpus (1)

• Influence of oxygen-coordination number on the electronic structure of single-layer La-based cuprates