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arXiv · 0804.2582

Superconductivity and Phase Diagram in the Iron-based Arsenic-oxides ReFeAsO1-delta (Re = rare earth metal) without F-Doping

Zhi-An Ren·Guang-Can Che·Xiao-Li Dong·Jie Yang·Wei Lu·Wei Yi·Xiao-Li Shen·Zheng-Cai Li·Li-Ling Sun·Fang Zhou·Zhong-Xian Zhao
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Abstract

Here we report a new class of superconductors prepared by high pressure synthesis in the quaternary family ReFeAsO1-delta (Re = Sm, Nd, Pr, Ce, La) without fluorine doping. The onset superconducting critical temperature (Tc) in these compounds increases with the reduction of Re atom size, and the highest Tc obtained so far is 55 K in SmFeAsO1-delta. For the NdFeAsO1-delta system with different oxygen concentration a dome-shaped phase diagram was found.

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Zhi-An Ren, Guang-Can Che, Xiao-Li Dong, Jie Yang, Wei Lu, Wei Yi, Xiao-Li Shen, Zheng-Cai Li, Li-Ling Sun, Fang Zhou, Zhong-Xian Zhao. 2008-04-16. Superconductivity and Phase Diagram in the Iron-based Arsenic-oxides ReFeAsO1-delta (Re = rare earth metal) without F-Doping. https://doi.org/10.1209/0295-5075/83/17002

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