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arXiv · 1009.4002

Single Crystal Growth and Characterization of the Iron-Based Superconductor KFe2As2 Synthesized by KAs Flux Method

Kunihiro Kihou·Taku Saito·Shigeyuki Ishida·Masamichi Nakajima·Yasuhide Tomioka·Hideto Fukazawa·Yoh Kohori·Toshimitsu Ito·Shin-ichi Uchida·Akira Iyo·Chul-Ho Lee·Hiroshi Eisaki
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Abstract

Centimeter sized platelet single crystals of KFe2As2 were grown using a self-flux method. An encapsulation technique using commercial stainless steel container allowed the stable crystal growth lasting for more than 2 weeks. Ternary K-Fe-As systems with various starting compositions were examined to determine the optimal growth conditions. Employment of KAs flux led to the growth of large single crystals with the typical size of as large as 15 mm x 10 mm x 0.4 mm. The grown crystals exhibit sharp superconducting transition at 3.4 K with the transition width 0.2 K, as well as the very large residual resistivity ratio exceeding 450, evidencing the good sample quality.

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Kunihiro Kihou, Taku Saito, Shigeyuki Ishida, Masamichi Nakajima, Yasuhide Tomioka, Hideto Fukazawa, Yoh Kohori, Toshimitsu Ito, Shin-ichi Uchida, Akira Iyo, Chul-Ho Lee, Hiroshi Eisaki. 2010-09-21. Single Crystal Growth and Characterization of the Iron-Based Superconductor KFe2As2 Synthesized by KAs Flux Method. https://doi.org/10.1143/jpsj.79.124713

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