Competition, coexistence and interplay between magnetic order, Kondo effect and superconductivity in heavy-fermion compounds

The mean-field theory based on a new high-degeneracy model is derived to describe an interplay between magnetic order, the Kondo effect and superconductivity in heavy-fermion compounds. The competition and coexistence of the Kondo effect and ferro- and antiferromagnetic orders of localized moments are considered in detail. It is shown that an antiferromagnetic order arising in the coherent Kondo state has an anomalously small antiferromagnetic moment per f-atom (∼10-2μB) and stimulates superconductivity with an anisotropic superconducting gap which vanishes along lines on the Fermi surface. (orig.)