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arXiv · 1106.6091

Topological competition of superconductivity in Pb/Ru/Sr_2RuO_4 junctions

Taketomo Nakamura·R. Nakagawa·T. Yamagishi·T. Terashima·S. Yonezawa·M. Sigrist·Y. Maeno
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Abstract

We devise a new proximity junction configuration where an s-wave superconductivity and the superconductivity of Sr2RuO4 interfere with each other. We reproducibly observe in such a Pb/Ru/Sr2RuO4 junction with a single Pb electrode that the critical current Ic drops sharply just below the bulk Tc of Sr2RuO4 and furthermore increases again below a certain temperature below Tc. In order to explain this extraordinary temperature dependence of Ic, we propose a competition effect involving topologically distinct superconducting phases around Ru inclusions. Thus, such a device may be called a "topological superconducting junction".

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Taketomo Nakamura, R. Nakagawa, T. Yamagishi, T. Terashima, S. Yonezawa, M. Sigrist, Y. Maeno. 2011-06-30. Topological competition of superconductivity in Pb/Ru/Sr_2RuO_4 junctions. https://doi.org/10.1103/physrevb.84.060512

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