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arXiv · 0811.1077

Reduction dependence of superconductivity in undoped T' cuprates

Osamu Matsumoto·Aya Utsuki·Akio Tsukada·Hideki Yamamoto·Takaaki Manabe·Michio Naito
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Abstract

We have recently achieved superconductivity in undoped T'-RE2CuO4 (RE: Pr, Nd, Sm, Eu, and Gd), using epitaxial thin films by metal organic decomposition. The key recipes to achieve superconductivity are low-PO2 firing and subsequent vacuum reduction to minimize the amount of impurity oxygen atoms, which are very harmful to high-Tc superconductivity. In this article, we report our investigation on the reduction dependence of superconductivity of T'-RE2CuO4. For thin films, the amount of remnant Oap atoms is difficult to evaluate but we propose that one good measure for this may be the c-axis lattice constant, which tells us whether the reduction is insufficient or excessive.

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Osamu Matsumoto, Aya Utsuki, Akio Tsukada, Hideki Yamamoto, Takaaki Manabe, Michio Naito. 2008-11-07. Reduction dependence of superconductivity in undoped T' cuprates. https://doi.org/10.1016/j.physc.2009.05.105

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