Pairing Correlations around Negative-U Centre in the Two-Band Model
A. Ciechan and K.I. Wysokiński
Institute of Physics and Nanotechnology Centre, M. Curie-Skłodowska University, Radziszewskiego 10, PL-20-031 Lublin, Poland
Full Text PDF
Received: 6 11 2007;
The electron energy spectrum of many superconducting materials is characterised by the presence of few bands at the Fermi level. In some cases the superconducting properties seem to be dominated by single band but in others the many-band approach is essential ingredient of their description. In this paper we shall study the properties of superconducting impurity placed in a non-superconducting medium. We are interested in the evolution of superconducting correlations within non-superconducting 1- or 2-dimensional system, their dependence on the distance from impurity and changes induced by the presence of the second band and interband scattering. We use real space description of the material and Bogolyubov-de Gennes approach to superconductivity.
DOI: 10.12693/APhysPolA.114.123
PACS numbers: 74.20.-z, 74.81.-g, 74.90.+n