Datensatz

Zusammenfassung

We present the Bethe ansatz solution of a magnetic hybridization impurity in a correlated electron host with Ising-like magnetic anisotropy. On the one hand, the strong correlations between host electrons produce a mixed-valence behavior of the localized electrons. On the other hand, the spin-gap of the low-lying unbound electron states caused by the "easy-axis" magnetic anisotropy suppresses the standard Kondo effect. For small enough magnetic fields the magnetic susceptibility of the impurity is zero. The usual Kondo logarithms, characteristic of SU(2)-symmetric systems with gapless spin-carrying excitations, are replaced by square root singularities caused by the closing of the spin gap at a critical field. Similar behavior is predicted for the free edges of an open chain, which again is very different from the isotropic situation. Using the low-lying excitations in the conformal regime we calculate asymptotics of correlation functions.