KONDO IMPURITY BAND IN A ONE-DIMENSIONAL CORRELATED ELECTRON LATTICE

We consider a system consisting of a one-dimensional lattice gas of el ectrons with a finite concentration of magnetic impurities. The host e lectrons propagate with nearest-neighbor hopping t, constrained by the excluded multiple occupancy of the lattice sites, and interact with e lectrons on neighboring sites via spin exchange J and a charge interac tion. The host is integrable at the supersymmetric point J = 2t, where charges and spin form a SU(3) BBB permutation algebra (this differs f rom the graded FFB superalgebra of the traditional supersymmetric t-J model, where B and F stand for boronic and fermionic degree of freedom ). Without destroying the integrability, we introduce a finite concent ration of impurities of arbitrary spin S, which hybridize with the con duction states of the host. We derive the Bethe ansatz equations diago nalizing the correlated host with impurities and discuss the ground-st ate properties as a function of magnetic field and the Kondo exchange coupling. While an isolated impurity of spin S>1/2 has a magnetic grou nd state of effective spin S-1/2, a finite concentration introduces an additional Dirac sea (the impurity band), which gives rise to a singl et groundstate. The impurities are antiferromagnetically correlated an d frustrated in zero field. As a function of the field, first the narr ow impurity band is spin polarized. The Van Hove singularities of the spin-rapidity bands define critical fields at which the susceptibility diverges. The impurities have in general mixed valent properties indu ced in part by the correlations in the host. Some of the aspects of th e model are related to heavy-fermion alloys. A distribution of Kondo t emperatures may give rise to non-Fermi-liquid properties.