ABSTRACT
Formation of the many-body Kondo singlet is qualitatively different from the usual Lindhard screening of impurities due to polarization of conduction electrons. An atom that is magnetic in one metallic host may not retain a magnetic moment when introduced in another metal. Poor man's scaling is not adequate for obtaining impurity properties in the low temperature regime of overscreened Kondo models. Nearly a decade before the study of the multichannel Kondo model by P. Nozieres and A. Blandin, A. I. Larkin and V. I. Mel’nikov in 1971 serendipitously discovered the multichannel Kondo effect while studying the effect of a magnetic impurity in the vicinity of a ferromagnetic quantum critical point, although they did not recognize the phenomenon in its entirety. The Schrieffer-Wolff transformation helps us recognize the origin of the Kondo coupling in virtual ionization of the P. W. Anderson impurity atom.
