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Title: Superconductivity in a uranium containing high entropy alloy

High entropy alloys (HEA) are an unusual class of materials where mixtures of elements are stochastically arrayed on a simple crystalline lattice. These systems exhibit remarkable functionality, often along several distinct axes: e.g., the examples [TaNb]1-x(TiZrHf)xare high strength and damage resistant refractory metals that also exhibit superconductivity with large upper critical fields. Here we report the discovery of anf-electron containing HEA, [TaNb]0.31(TiUHf)0.69, which is the first to include an actinide ion. Similar to the Zr-analogue, this material crystallizes in a body-centered cubic lattice with the lattice constanta = 3.41(1) Å and exhibits phonon mediated superconductivity with a transition temperaturesTc ≈ 3.2 K and upper critical fieldsHc2 ≈ 6.4 T. These results expand this class of materials to include actinide elements, shows that superconductivity is robust in this sub-group, and opens the path towards leveraging HEAs as functional waste forms for a variety of radioisotopes.

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Publication Date:
Journal Name:
Scientific Reports
Nature Publishing Group
Sponsoring Org:
National Science Foundation
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