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In-situ epitaxial growth of superconducting La-based bilayer cuprate thin films

I. Tsukada·Y. Nagao·Yoichi Ando
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Abstract

We investigate the epitaxial growth of bilayer cuprate La2CaCu2O6+δusing pure ozone as an oxidant, and find that even the crystal with parent composition without cation substitution can show metallic behavior with the aid of epitaxial strain effect. The hole concentration is controlled simply by excess-oxygen doping, and the films grown under the optimum conditions exhibit superconductivity below 30 K. This is the first result on the superconductivity of bilayer La2CaCu2O6+δinduced purely by the excess oxygen.

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I. Tsukada, Y. Nagao, Yoichi Ando. 2003-12-17. In-situ epitaxial growth of superconducting La-based bilayer cuprate thin films. https://doi.org/10.1103/physrevb.69.020504

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