Multiband superconductivity in Pb, H under pressure and CaBeSi from {\it ab-initio} calculations

TL;DR

This paper uses ab-initio calculations to analyze multiband superconductivity in Pb, H under pressure, and CaBeSi, revealing how electron interactions influence superconducting properties and conditions for multigap behavior.

Contribution

It provides a detailed ab-initio analysis of multiband superconductivity in specific materials, advancing understanding of anisotropic superconductivity from first principles.

Findings

Pb, H under pressure and CaBeSi are multigap superconductors.

Electron-phonon and electron-electron interactions determine superconducting gap and Tc.

Conditions for multigap superconductivity are identified.

Abstract

Superconductivity in Pb, H under extreme pressure and CaBeSi, in the framework of the density functional theory for superconductors, is discussed. A detailed analysis on how the electron-phonon and electron-electron interactions combine together to determine the superconducting gap and critical temperature of these systems is presented. Pb, H under pressure and CaBeSi are multigap superconductors. We will address the question under which conditions does a system exhibits this phenomenon. The presented results contribute to the understanding of multiband and anisotropic superconductivity, which has received a lot of attention since the discovery of MgB$_2$, and show how it is possible to describe the superconducting properties of real materials on a fully {\it ab-initio} basis.