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arXiv · 0805.4340

Nickel-based layered superconductor, LaNiOAs

Takumi Watanabe·Hiroshi Yanagi·Yoichi Kamihara·Toshio Kamiya·Masahiro Hirano·Hideo Hosono
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Abstract

Rietveld analysis of the powder X-ray diffraction of a new layered oxyarsenide, LaNiOAs, which was synthesized by solid-state reactions, revealed that LaNiOAs belongs to the tetragonal ZrCuSiAs-type structure (P4/nmm) and is composed of alternating stacks of La-O and Ni-As layers. The electrical and magnetic measurements demonstrated that LaNiOAs exhibits a superconducting transition at 2.4 K, and above this, LaNiOAs shows metallic conduction and Pauli paramagnetism. The diamagnetic susceptibility measured at 1.8 K corresponded to ~20% of perfect diamagnetic susceptibility, substantiating that LaNiOAs is a bulk superconductor.

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Takumi Watanabe, Hiroshi Yanagi, Yoichi Kamihara, Toshio Kamiya, Masahiro Hirano, Hideo Hosono. 2008-05-28. Nickel-based layered superconductor, LaNiOAs. https://doi.org/10.1016/j.jssc.2008.04.033

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