Re-entrance of resistivity due to the interplay of superconductivity and magnetism in $\ce{Eu_{0.73}Ca_{0.27}(Fe_{0.87}Co_{0.13})2As2}$

Lan Maria Tran; Andrzej J. Zaleski; Zbigniew Bukowski

doi:10.1103/physrevb.109.014509

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arXiv · 2309.04308

Re-entrance of resistivity due to the interplay of superconductivity and magnetism in $\ce{Eu_{0.73}Ca_{0.27}(Fe_{0.87}Co_{0.13})2As2}$

Lan Maria Tran·Andrzej J. Zaleski·Zbigniew Bukowski

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Abstract

By simultaneous Co and Ca-doping we were able to obtain an $\ce{EuFe2As2}$-based compound with superconductivity appearing above the antiferromagnetic order of $\ce{Eu^{2+}}$ magnetic moments. However, as soon as the antiferromagnetic order appears a re-entrance behavior is observed \textemdash{} instead of zero resistivity and diamagnetic signal down to the temperature of \unit[2]{K}. By investigating magnetization, ac susceptibility and electrical transport properties of $\ce{Eu_{0.73}Ca_{0.27}(Fe_{0.87}Co_{0.13})2As2}$ and comparing them to previously studied M\"ossbauer effect and neutron scattering measurements of this and similar compounds an explanation of such behavior is proposed.

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Lan Maria Tran, Andrzej J. Zaleski, Zbigniew Bukowski. 2023-09-08. Re-entrance of resistivity due to the interplay of superconductivity and magnetism in $\ce{Eu_{0.73}Ca_{0.27}(Fe_{0.87}Co_{0.13})2As2}$. https://doi.org/10.1103/physrevb.109.014509

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