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arXiv · 1607.05371

Superconductivity in CeOBiS2 with cerium valence fluctuation

Masanori Nagao·Akira Miura·Ikuo Ueta·Satoshi Watauchi·Isao Tanaka
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Abstract

Resistivities of single-crystalline as well as poly-crystalline samples of CeOBiS2 without fluorine doping were measured at temperatures down to 0.13 K, and were compared with those of poly-crystalline LaOBiS2 and PrOBiS2. Both poly-crystalline and single-crystalline CeOBiS2 exhibited zero resistivity below 1.2 K while poly-crystalline LaOBiS2 and PrOBiS2 did not show zero resistivity down to 0.13 K. Superconducting transition temperature of CeOBiS2 was reduced by increasing the applied current density. The superconductivity of CeOBiS2 without chemical doping is likely triggered by the carriers induced by the valence fluctuation between Ce3+ and Ce4+.

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Masanori Nagao, Akira Miura, Ikuo Ueta, Satoshi Watauchi, Isao Tanaka. 2016-07-19. Superconductivity in CeOBiS2 with cerium valence fluctuation. https://doi.org/10.1016/j.ssc.2016.07.017

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