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Superconductivity of epsilon-Fe: complete resistive transition

D. Jaccard·A. T. Holmes·G. Behr·Y. Inada·Y. Onuki
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Abstract

Last year, iron was reported to become superconducting at temperatures below 2K and pressures between 15 and 30 GPa. The evidence presented was a weak resistivity drop, suppressed by a magnetic field above 0.2 T, and a small Meissner signal. However, a compelling demonstration, such as the occurrence of zero resistance, was lacking. Here we report the measurement of a complete resistive transition at 22.2 GPa with an onset slightly above 2 K in two very pure samples of iron, of different origins. The superconductivity appears unusually sensitive to disorder, developing only when the electronic mean free path is above a threshold value, while the normal state resistivity is characteristic of a nearly ferromagnetic metal.

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D. Jaccard, A. T. Holmes, G. Behr, Y. Inada, Y. Onuki. 2002-05-27. Superconductivity of epsilon-Fe: complete resistive transition. https://doi.org/10.1016/s0375-9601(02)00725-9

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