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The enhancement of superconducting transition temperature in yttrium sesquicarbide system, Y2C3, with the maximum Tc of Tc=18K

G. Amano·S. Akutagawa·T. Muranaka·Y. Zenitani·J. Akimitsu
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Abstract

We discovered the enhancement of superconducting transition temperature, Tc, in yttrium sesquicarbide system with the maximum Tc of Tc=18K and their superconducting properties were discussed. The crystal structure of Y2C3 is the body-centered cubic (Pu2C3-type) structure, and the lattice parameters are varied with the heat treatment conditions. The magnetization (M-H) curves of this compound showed a typical type-II superconducting behavior, and the lower critical field, Hc1(0), is 3.5mT. The Tc-value in this system was changed in the range from 15K to 18K, depending on the sintering conditions. In a previous report by Krupka et al., maximum Tc in Y2C3 was observed at 11.5K by the magnetic measurements. So we successfully synthesized the new high-Tc phase in Y2C3.

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G. Amano, S. Akutagawa, T. Muranaka, Y. Zenitani, J. Akimitsu. 2003-11-22. The enhancement of superconducting transition temperature in yttrium sesquicarbide system, Y2C3, with the maximum Tc of Tc=18K. https://arxiv.org/abs/cond-mat/0311517

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