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arXiv · 1204.1335

Rare earth substitution in lattice-tuned Sr0.3Ca0.7Fe2As2 solid solutions

Tyler Drye·Shanta R. Saha·Peter Y. Zavalij·Johnpierre Paglione
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Abstract

The effects of aliovalent rare earth substitution on the physical properties of Sr0.3Ca0.7Fe2As2 solid solutions are explored. Electrical transport, magnetic susceptibility and structural characterization data as a function of La substitution into (Sr_1-y_Ca_y)_1-x_La_x_Fe2As2 single crystals confirm the ability to suppress the antiferromagnetic ordering temperature from 200 K in the undoped compound down to 100 K approaching the solubility limit of La. Despite up to ~30% La substitution, the persistence of magnetic order and lack of any signature of superconductivity above 10 K present a contrasting phase diagram to that of Ca1-xLaxFe2As2, indicating that the suppression of magnetic order is necessary to induce the high-temperature superconducting phase observed in Ca1-xLaxFe2As2.

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Tyler Drye, Shanta R. Saha, Peter Y. Zavalij, Johnpierre Paglione. 2012-04-04. Rare earth substitution in lattice-tuned Sr0.3Ca0.7Fe2As2 solid solutions. https://doi.org/10.1088/0953-2048%2F25%2F8%2F084014

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