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arXiv · 1210.5353

Superconductivity in defective pyrite-type iridium chalcogenides IrxCh2 (Ch = Se and Te)

Yanpeng Qi·Satoru Matsuishi·Jiangang Guo·Hiroshi Mizoguchi·Hideo Hosono
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Abstract

We report superconductivity in defective pyrite-type iridium chalcogenides IrxCh2. Maximum values of Tc of 6.4 K for Ir0.91Se2 and 4.7 K for Ir0.93Te2 were observed. It was found that Ir0.75Ch2 is close to the boundary between metallic and insulating states and IrxCh2 systems undergo nonmetal to metal transitions as x increases. On the basis of density functional theory calculations and the observed large variation in the Ch-Ch distance with x, we suggest that Ir0.75Ch2 is the parent compound for the present superconductors.

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Yanpeng Qi, Satoru Matsuishi, Jiangang Guo, Hiroshi Mizoguchi, Hideo Hosono. 2012-10-19. Superconductivity in defective pyrite-type iridium chalcogenides IrxCh2 (Ch = Se and Te). https://doi.org/10.1103/physrevlett.109.217002

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