Electronic, vibrational, and superconducting properties ofCaBeSi: first-principles calculations

Bersier, C. and Floris, A. and Sanna, A. and Profeta, G. and Continenza, A. and Gross, E. K. U. and Massidda, S. (2009) Electronic, vibrational, and superconducting properties ofCaBeSi: first-principles calculations. Physical Review B, 79 (10). ISSN 2469-9950

Full text not available from this repository.

Item Type:Article
Item Status:Live Archive

Abstract

We report first-principles calculations on the normal and superconducting state of CaBexSi2−x (x=1), in the framework of density-functional theory for superconductors. CaBeSi is isostructural and isoelectronic to MgB2 and this makes possible a direct comparison of the electronic and vibrational properties and the electron-phonon interaction of the two materials. Despite many similarities with MgB2 (e.g., σ and π bands at the Fermi level and an even larger density of states), according to our calculations CaBeSi has a very low critical temperature Tc≈0.4 K consistent with the experiment. CaBeSi exhibits a complex gap structure, with three gaps at the Fermi level: besides the σ and π gaps (present also in MgB2), the appearance of a third gap is related to the anisotropy of the Coulomb repulsion, acting in different ways on the bonding and antibonding electronic π states.

Keywords:Superconductors
Subjects:F Physical Sciences > F300 Physics
Divisions:College of Science > School of Mathematics and Physics
Related URLs:
ID Code:22799
Deposited On:02 Jun 2016 12:33

Repository Staff Only: item control page