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Intrinsic electron-doping in nominal "non-doped" superconducting (La,Y)$_2$CuO$_4$ thin films grown by dc magnetron sputtering

L. Zhao·G. Wu·R. H. Liu·X. H. Chen
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Abstract

The superconducting nominal "non-doped" $La_{1.85}Y_{0.15}CuO_4$ (LYCO) thin films are successfully prepared by dc magnetron-sputtering and in situ post-annealing in vacuum. The best $T_{C0}$ more than 13K is achieved in the optimal LYCO films with highly pure c-axis oriented T'-type structure. In the normal state, the quasi-quadratic temperature dependence of resistivity, the negative Hall coefficient and effect of oxygen content in the films are quite similar to the typical Ce-doped T'-214 cuprates, suggesting that T'-LYCO shows the electron-doping nature like known n-type cuprates, and is not a band superconductor as proposed previously. The charge carriers are considered to be induced by oxygen deficiency.

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L. Zhao, G. Wu, R. H. Liu, X. H. Chen. 2006-11-05. Intrinsic electron-doping in nominal "non-doped" superconducting (La,Y)$_2$CuO$_4$ thin films grown by dc magnetron sputtering. https://doi.org/10.1063/1.2569043

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