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arXiv · 1311.1302

Discovery of New Layered Iron Arsenide Superconductor (Ca,Pr)FeAs2

Hiroyuki Yakita·Hiraku Ogino·Tomoyuki Okada·Akiyasu Yamamoto·Kohji Kishio·Tetsuya Tohei·Yuichi Ikuhara·Yoshito Gotoh·Hiroshi Fujihisa·Kunimitsu Kataoka·Hiroshi Eisaki·Jun-ichi Shimoyama
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Abstract

A new iron-based superconductor (Ca,Pr)FeAs2 was discovered. Plate-like crystals of the new phase were obtained and crystal structure was investigated by single-crystal X-ray diffraction analysis. The structure was identified as the monoclinic system with space group P21/m, and is composed of two Ca(Pr) planes, anti-fluorite Fe2As2 layers, and As2 zigzag chain layers. Plate-like crystals composed of the new phase showed superconductivity with Tc ~20 K in both magnetization and resistivity measurements.

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Hiroyuki Yakita, Hiraku Ogino, Tomoyuki Okada, Akiyasu Yamamoto, Kohji Kishio, Tetsuya Tohei, Yuichi Ikuhara, Yoshito Gotoh, Hiroshi Fujihisa, Kunimitsu Kataoka, Hiroshi Eisaki, Jun-ichi Shimoyama. 2013-11-06. Discovery of New Layered Iron Arsenide Superconductor (Ca,Pr)FeAs2. https://doi.org/10.1021/ja410845b

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