Coulomb interactions in conventional Superconductivity
Antonio Sanna
Max Planck Institute of Microstructure Physics - Halle
16:15 - 17:15 Tuesday 25 April 2023 TUG First principle methods to simulate conventional superconductors rely, primarily, on the accurate calculation of the electron phonon coupling. However, phonon mediated attraction is partly compensated by an excess electron-electron Coulomb repulsion associated with the formation of Cooper pairs. In most studies such Coulomb effects are treated with a simplistic approximation: the Morel-Anderson mu*.
In this presentation I review the theory of conventional superconductivity making a case for the importance of accurate inclusion of Coulomb effects beyond Morel Anderson theory.
I will focus on the following three aspects:
1) including Coulomb interaction in material simulation retaining both accuracy and computational efficiency;
2) investigating the role of dynamical Coulomb effects and plasmonic pairing;
3) studying the validity of the RPA approximation and the importance of vertex corrections.
I will mostly stay within the framework of Eliashberg theory, discussing advantages and disadvantages with respect to Density functional Theory for Superconductors.
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