Structural Analysis and Superconducting Properties of F-Substituted NdOBiS2 Single Crystals

Masanori Nagao; Satoshi Demura; Keita Deguchi; Akira Miura; Satoshi Watauchi; Takahiro Takei; Yoshihiko Takano; Nobuhiro Kumada; Isao Tanaka

doi:10.7566/jpsj.82.113701

arXiv · 1309.6400

Structural Analysis and Superconducting Properties of F-Substituted NdOBiS2 Single Crystals

Masanori Nagao·Satoshi Demura·Keita Deguchi·Akira Miura·Satoshi Watauchi·Takahiro Takei·Yoshihiko Takano·Nobuhiro Kumada·Isao Tanaka

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Abstract

F-substituted NdOBiS2 superconducting single crystals were grown using CsCl/KCl flux. This is the first example of the single-crystal growth of a BiS2-based superconductor. The obtained single crystals had a plate-like shape with a size of 1-2 mm and a well-developed ab-plane. The crystal structure of the grown crystals was determined by single-crystal X-ray diffraction analysis to be the tetragonal space group P4/nmm (#129) with a = 3.996(3) A and c = 13.464(6) A. The chemical formula of the grown crystals was approximately Nd0.98(0.06)O0.7(0.1)F0.3(0.1)Bi0.98(0.04)S2, and Cs, K, and Cl were not detected in the grown crystals by electron probe microanalysis. The grown crystals had a critical temperature of approximately 5 K. The superconducting anisotropy of the single crystals was estimated to be about 30 from the effective mass model and the upper critical field.

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Masanori Nagao, Satoshi Demura, Keita Deguchi, Akira Miura, Satoshi Watauchi, Takahiro Takei, Yoshihiko Takano, Nobuhiro Kumada, Isao Tanaka. 2013-09-25. Structural Analysis and Superconducting Properties of F-Substituted NdOBiS2 Single Crystals. https://doi.org/10.7566/jpsj.82.113701

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