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arXiv · 1805.09835

A Family of Pb-based Superconductors with Variable Cubic to Hexagonal Packing

Tai Kong·Karolina Górnicka·Sylwia Gołąb·Bartlomiej Wiendlocha·Tomasz Klimczuk·Robert. J. Cava
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Abstract

We describe three previously unreported superconductors, BaPb3, Ba0.89Sr0.11Pb3 and Ba0.5Sr0.5Pb3. These three materials, together with SrPb3, form a distinctive isoelectronic family of intermetallic superconductors based on the stacking of Pb planes, with crystal structures that display a hexagonal to cubic perovskite-like progression, as rarely seen in metals. The superconducting transition temperatures (Tc) are similar for all - 2.2 K for BaPb3, 2.7 K for Ba0.89Sr0.11Pb3 and 2.6 K for Ba0.5Sr0.5Pb3, and the previously reported Tc of SrPb3, ~ 2 K, is confirmed. The materials are moderate coupling superconductors, and calculations show that the electronic densities of states at the Fermi energy are primarily contributed by Pb. The observations suggest that the Pb-stacking variation has only a minor effect on the superconductivity.

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Tai Kong, Karolina Górnicka, Sylwia Gołąb, Bartlomiej Wiendlocha, Tomasz Klimczuk, Robert. J. Cava. 2018-05-24. A Family of Pb-based Superconductors with Variable Cubic to Hexagonal Packing. https://doi.org/10.7566/jpsj.87.074711

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