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The many-band approach is essential to describe a lot of superconducting materials like MgB_2 [1], Sr_2RuO_4 [2] or recently discovered superconducting quaternary pnictides [3], as e.g. LaO_F_xFeAs [4]. The presence of second band even with repulsive electron-electron interaction might lead to increase of pairing correlations and superconducting transition temperature if the bands interact with each other [5]. In this work we study the consequences of the two band spectrum and interband pair scattering on the local properties of superconductor. By numerically solving real space Bogolubov-deGennes equations we obtain local values of the order parameter and local density of states. These characteristics have recently been measured via scanning tunnelling microscope. For simplicity we assume that the superconductor is described by local, random version of negative U Hubbard model. [1] J. Karpinski et al., Supercond. Sci. Technol. 16, 221 (2003). [2] J. F. Annett et al., Phys. Rev. B 66, 134514 (2002). [3] Y. Kamihara et al., J. Am. Chem. Soc. 128, 10012 (2006) [4] Y. Kamihara et al., J. Am. Chem. Soc. 130, 3296 (2008) [5] J. Kondo, Prog. Theor. Phys. 29,1 (1963) |
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