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arXiv · 1702.01196

Bi Substitution Effects on Superconductivity of Valence-Skip superconductor AgSnSe2

Yudai Hijikata·Atsuhiro Nishida·Kohei Nagasaka·Osuke Miura·Akira Miura·Chikako Moriyoshi·Yoshihiro Kuroiwa·Yoshikazu Mizuguchi
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Abstract

We have synthesized AgSn1-xBixSe2 polycrystalline samples to investigate the effect of partial substitution of mixed-valence Sn by Bi3+ to the superconductivity of the valence-skip superconductor AgSnSe2. The Bi-substituted AgSn1-xBixSe2 were obtained up to x = 0.2, but an insulating phase Ag2SnBi2Se5 with a NaCl-type structure showed up above x = 0.3. The superconducting transition temperature increased from 4.5 K (x = 0) to 5.0 K (x = 0.1) by Bi substitution. The enhancement of superconductivity by the suppression of the valence-skip states of Sn suggests that the valence-skip states of Sn are not positively linked to the pairing mechanisms of superconductivity in the AgSnSe2 system.

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Yudai Hijikata, Atsuhiro Nishida, Kohei Nagasaka, Osuke Miura, Akira Miura, Chikako Moriyoshi, Yoshihiro Kuroiwa, Yoshikazu Mizuguchi. 2017-02-03. Bi Substitution Effects on Superconductivity of Valence-Skip superconductor AgSnSe2. https://doi.org/10.7566/jpsj.86.054711

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