Quasiparticle properties of the possible superconductor materials andS. Lebègue1, B. Arnaud2, P. Rabiller2, M. Alouani1 and W. E. Pickett3
1 Institut de Physique et de Chimie des Matériaux de Strasbourg (IPCMS) UMR 7504 du CNRS - 23 rue du Loess, 67037 Strasbourg, France
2 Groupe Matière condensée et Matériaux (GMCM), Campus de Beaulieu Bât. 11A - 35042 Rennes cedex, France
3 Department of Physics, University of California - Davis, CA 95616, USA
received 13 September 2004; accepted 22 October 2004
published online 30 November 2004
The quasiparticle band structures within the GW approximation of the possible superconductors and are presented. The GW correction to the LDA is shown to be strongly dependent on the degree of orbital localization, and the overall correction cannot be reproduced by a rigid band shift as in conventional semiconductors. Precise values of the interband transitions for high-symmetry points in the Brillouin zone are given. The imaginary part of the self-energy which is related to the lifetime of quasiparticles, is presented in order to be compared with future experiments. Moreover, the ground-state properties of and are studied and it is shown that the bonding is partly covalent.
71.15.Mb - Density functional theory, local density approximation, gradient and other corrections.
© EDP Sciences 2004