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arXiv · 1402.3387

Unification of the Pressure and Composition Dependence of Superconductivity in Ru substituted BaFe2As2

T. R. Devidas·Awadhesh Mani·Shilpam Sharma·K. Vinod·A. Bharathi·C. S. Sundar
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Abstract

Temperature dependent high pressure electrical resistivity studies has been carried out on Ba(Fe_{1-x}Ru_{x})_{2}As_{2} single crystals with x = 0.12, 0.26 and 0.35, which correspond to under doped, optimally doped and over doped composition regimes respectively. The evolution of structural/magnetic (T_{S-M}) and superconducting transition (T_(c)) temperatures, with pressure for various compositions have been obtained. The normal state resistivity has been analyzed in terms of a model that incorporates both spin fluctuations and the opening of the gap in the spin density wave (SDW)phase. It is shown that Tc scales with the strength of the spin fluctuation, B, and T_{S-M} scales with the SDW gap parameter, Δ. This provides a prescription for the unification of the composition and pressure induced superconductivity in BaFe2As2.

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T. R. Devidas, Awadhesh Mani, Shilpam Sharma, K. Vinod, A. Bharathi, C. S. Sundar. 2014-02-14. Unification of the Pressure and Composition Dependence of Superconductivity in Ru substituted BaFe2As2. https://doi.org/10.1016/j.ssc.2014.02.002%2010.1016%2Fj.ssc.2014.02.002

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