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arXiv · 0903.3710

Water-induced superconductivity in SrFe2As2

Hidenori Hiramatsu·Takayoshi Katase·Toshio Kamiya·Masahiro Hirano·Hideo Hosono
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Abstract

It has been considered that FeAs-based high transition temperature (high-Tc) superconductors need electron or hole doping by aliovalent ion substitution or large off-stoichiometry in order to induce superconductivity. We report that exposure of undoped SrFe2As2 epitaxial thin films to water vapor induces a superconducting transition. These films exhibit a higher onset-Tc (25 K) and larger magnetic field anisotropy than those of cobalt-doped SrFe2As2 epitaxial films, suggesting that the mechanism for the observed superconducting transition differs from that of the aliovalent-ion doped SrFe2As2. The present finding provides a new approach to induce superconductivity with a higher Tc in FeAs-based superconductors.

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Hidenori Hiramatsu, Takayoshi Katase, Toshio Kamiya, Masahiro Hirano, Hideo Hosono. 2009-03-22. Water-induced superconductivity in SrFe2As2. https://doi.org/10.1103/physrevb.80.052501

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