Superconductivity of Ta₃₄Nb₃₃Hf₈Zr₁₄Ti₁₁ high entropy alloy from first principles calculations

Abstract

The Korringa–Kohn–Rostoker method with the coherent potental approximation (KKR‐CPA) is applied to study the first superconducting high entropy alloy (HEA) Ta 34 Nb 33 Hf 8 Zr 14 Ti 11 (discovered in 2014 with T c = 7.3 K), focusing on estimations of the electron–phonon coupling constant λ . The electronic part of λ has 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. (© 2016 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)