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arXiv · 1012.2924

Superconductivity in the iron selenide KxFe2Se2 (0 <= x <= 1)

Jiangang Guo·Shifeng Jin·Gang Wang·Shunchong Wang·Kaixing Zhu·Tingting Zhou·Meng He·Xiaolong Chen
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Abstract

We report the superconductivity at above 30 K in a new FeSe-layer compound K0.8Fe2Se2 (nominal composition) achieved by metal K intercalating in between FeSe layers. It is isostructural to BaFe2As2 and possesses the highest Tc for FeSe-layer materials so far under ambient pressure. Hall effect indicates the carriers are dominated by electron in this superconductor. We confirm that the observed superconductivity at above 30 K is due to this new FeSe-based 122 phase. Our results demonstrate that FeSe-layer materials are really remarkable superconductors via structure and carrier modulation.

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Jiangang Guo, Shifeng Jin, Gang Wang, Shunchong Wang, Kaixing Zhu, Tingting Zhou, Meng He, Xiaolong Chen. 2010-12-14. Superconductivity in the iron selenide KxFe2Se2 (0 <= x <= 1). https://doi.org/10.1016/j.physc.2011.04.009

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