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arXiv · 2106.09863

Fluorine solubility and superconducting properties of Sm(O,F)BiS$_2$ single crystals

Koki Kinami·Yuji Hanada·Masanori Nagao·Akira Miura·Shigeto Hirai·Yuki Maruyama·Satoshi Watauchi·Isao Tanaka
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Abstract

Sm(O,F)BiS2 superconducting single crystals with various nominal F contents have been grown using KI-KCl flux. The solid solution limit of F at the O-site in Sm(O,F)BiS2 single crystals was approximately less than 20 at%. F concentrations of Sm(O,F)BiS2 single crystals were hardly controlled by nominal F contents. It suggests the existence of intrinsic stable phase. Superconductivity was shown at around 5 K. Superconducting transition temperature with zero resistivity were increased with increasing nominal F contents within less than 70 at% in O-site, despite similar F concentration and c-axis lattice constants.

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Koki Kinami, Yuji Hanada, Masanori Nagao, Akira Miura, Shigeto Hirai, Yuki Maruyama, Satoshi Watauchi, Isao Tanaka. 2021-06-18. Fluorine solubility and superconducting properties of Sm(O,F)BiS$_2$ single crystals. https://doi.org/10.1016/j.jallcom.2021.160812

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