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arXiv · 1603.07274

Superconductivity of Ta34Nb33Hf8Zr14Ti11 high entropy alloy from first principles calculations

K. Jasiewicz·B. Wiendlocha·P. Korbeń·S. Kaprzyk·J. Tobola
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Abstract

The Korringa-Kohn-Rostoker method with the coherent potental approximation (KKR-CPA) is applied to study the first superconducting high entropy alloy (HEA) Ta34Nb33Hf8Zr14Ti11 (discovered in 2014 with Tc = 7.3 K), focusing on estimations of the electron-phonon coupling constant λ. Electronic part of λhas been calculated using the rigid muffin-tin approximation (RMTA), while the phonon part has been approximated using average atomic mass and experimental Debye temperature. The estimated λ= 1.16 is close to the value determined from specific heat measurements, λ= 0.98, and suggests rather strong electron-phonon coupling in this material.

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K. Jasiewicz, B. Wiendlocha, P. Korbeń, S. Kaprzyk, J. Tobola. 2016-03-23. Superconductivity of Ta34Nb33Hf8Zr14Ti11 high entropy alloy from first principles calculations. https://doi.org/10.1002/pssr.201600056

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