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arXiv · 1211.3345

Anisotropic Migdal-Eliashberg theory using Wannier functions

E. R. Margine·F. Giustino
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Abstract

We combine the fully anisotropic Migdal-Eliashberg theory with electron-phonon interpolation based on maximally-localized Wannier functions, in order to perform reliable and highly accurate calculations of the anisotropic temperature-dependent superconducting gap and critical temperature of conventional superconductors. Compared with the widely used McMillan approximation, our methodology yields a more comprehensive and detailed description of superconducting properties, and is especially relevant for the study of layered or low-dimensional systems as well as systems with complex Fermi surfaces. In order to validate our method we perform calculations on two prototypical superconductors, Pb and MgB$_2$, and obtain good agreement with previous studies.

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E. R. Margine, F. Giustino. 2012-11-14. Anisotropic Migdal-Eliashberg theory using Wannier functions. https://doi.org/10.1103/physrevb.87.024505

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