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arXiv · 0903.4668

Superconductivity induced by ruthenium substitution in an iron arsenide: investigation of SrFe2-xRuxAs2 (0 <= x <= 2)

W. Schnelle·A. Leithe-Jasper·R. Gumeniuk·U. Burkhardt·D. Kasinathan·H. Rosner
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Abstract

The magnetism in SrFe2As2 can be suppressed by electron doping through a small substitution of Fe by Co or Ni, giving way to superconductivity. We demonstrate that a massive substitution of Fe by isovalent ruthenium similarly suppresses the magnetic ordering in SrFe2-xRuxAs2 and leads to bulk superconductivity for 0.6 <= x <= 0.8. Magnetization, electrical resistivity, and specific heat data show Tc up to approx 20K. Detailed structural investigations reveal a strong decrease of the lattice parameter ratio c/a with increasing x. DFT band structure calculations are in line with the observation that the magnetic order in SrFe2-xRuxAs2 is only destabilized for large x.

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W. Schnelle, A. Leithe-Jasper, R. Gumeniuk, U. Burkhardt, D. Kasinathan, H. Rosner. 2009-05-06. Superconductivity induced by ruthenium substitution in an iron arsenide: investigation of SrFe2-xRuxAs2 (0 <= x <= 2). https://doi.org/10.1103/physrevb.79.214516

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