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arXiv · 1903.02301

Type-I superconductivity in Al$_6$Re

Darren C. Peets·Erjian Cheng·Tianping Ying·Markus Kriener·Xiaoping Shen·Shiyan Li·Donglai Feng
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Abstract

While the pure elements tend to exhibit Type-I rather than Type-II superconductivity, nearly all compound superconductors are Type-II, with only a few known exceptions. We report single crystal growth and physical characterization of the rhenium aluminide Al$_6$Re, which we conclude is a Type-I superconductor based on magnetization, ac-susceptibility, and specific-heat measurements. This detection of superconductivity, despite the strong similarity of Al$_6$Re to a family of W and Mo aluminides that do not superconduct, suggests that these aluminides are an ideal testbed for identifying the relative importance of valence electron count and inversion symmetry in determining whether a material will superconduct.

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Darren C. Peets, Erjian Cheng, Tianping Ying, Markus Kriener, Xiaoping Shen, Shiyan Li, Donglai Feng. 2019-04-11. Type-I superconductivity in Al$_6$Re. https://doi.org/10.1103/physrevb.99.144519

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