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 TK/A (TK: Kondo temperature, A: superconducting energy gap).
- Kondo effect
- magnetic impurity
- numerical renormalization group