Numerical Renormalization Group Study of Magnetic Impurities in Superconductors. II. Dynamical Excitation Spectra and Spatial Variation of the Order Parameter

抄録

The Kondo problem in superconductors is studied by extending Wilson’s numerical renormalization group method. As a continuation to a previous paper (J. Phys. Soc. Jpn. 61 (1992) 3239), various problems related to the localized excited state produced by a magnetic impurity are examined in detail. In particular, the binding energy of the localized excited state, its spectral weight, one-electron and magnetic excitation spectra and the spatial variation of the order parameter are studied over the whole regime of the magnitude of T_K⁄Δ (T_K: Kondo temperature, Δ: superconducting energy gap).