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arXiv · 1303.4489

Emergence of superconductivity at 45 K by lanthanum and phosphorus co-doping of CaFe2As2

Kazutaka Kudo·Keita Iba·Masaya Takasuga·Yutaka Kitahama·Jun-ichi Matsumura·Masataka Danura·Yoshio Nogami·Minoru Nohara
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Abstract

Co-doping of lanthanum and phosphorus in CaFe2As2 induces superconductivity at 45 K. This superconducting transition temperature is higher than the 38 K transition in Ba1-xKxFe2As2, which is the maximum found thus far among the 122 phases. Superconductivity with a substantial shielding volume fraction was observed at 0.12 $\leq$ x $\leq$ 0.18 and y = 0.06 in Ca1-xLaxFe2(As1-yPy)2. The superconducting phase of the present system seems to be not adjacent to an antiferromagnetic phase.

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Kazutaka Kudo, Keita Iba, Masaya Takasuga, Yutaka Kitahama, Jun-ichi Matsumura, Masataka Danura, Yoshio Nogami, Minoru Nohara. 2013-03-19. Emergence of superconductivity at 45 K by lanthanum and phosphorus co-doping of CaFe2As2. https://doi.org/10.1038/srep01478

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