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arXiv · 1303.5138

Non-empirical Study of Superconductivity in Alkali-doped Fullerides Based on Density Functional Theory for Superconductors

Ryosuke Akashi·Ryotaro Arita
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Abstract

We apply the density functional theory for superconductors (SCDFT) based on the local-density approximation (LDA) to alkali-doped fullerides A3C60 with the face-centered cubic structure. We evaluate the superconducting transition temperature (Tc) from first principles considering energy dependence of electron-phonon coupling, the mass renormalization, and the retardation effect. The calculated Tc=7.5, 9.0 and 15.7 K for A=K, Rb, Cs are approximately 60 % smaller than the experimentally observed values. Our results strongly suggest necessity to go beyond the framework of the Migdal-Eliashberg theory based on the LDA.

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Ryosuke Akashi, Ryotaro Arita. 2013-03-21. Non-empirical Study of Superconductivity in Alkali-doped Fullerides Based on Density Functional Theory for Superconductors. https://doi.org/10.1103/physrevb.88.054510

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