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arXiv · 1409.7968

Superconducting pairing mediated by spin-fluctuations from first principles

F. Essenberger·A. Sanna·A. Linscheid·F. Tandetzky·G. Profeta·P. Cudazzo·E. K. U. Gross
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Abstract

We present the derivation of an ab-initio and parameter free effective electron-electron interaction that goes beyond the screened RPA and accounts for superconducting pairing driven by spin-fluctuations. The construction is based on many body perturbation theory and relies on the approximation of the exchange-correlation part of the electronic self-energy within time dependent density functional theory. This effective interaction is included in an exchange correlation kernel for superconducting density functional theory, in order to achieve a completely parameter free superconducting gap equation. First results from applying the new functional to a simplified two-band electron gas model are consistent with experiments.

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F. Essenberger, A. Sanna, A. Linscheid, F. Tandetzky, G. Profeta, P. Cudazzo, E. K. U. Gross. 2014-09-28. Superconducting pairing mediated by spin-fluctuations from first principles. https://doi.org/10.1103/physrevb.90.214504

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