Spin-triplet solitons in the one-dimensional symmetric Kondo lattice

By analyzing the Gutzwiller-projected, self-consistent mean-field solutions we demonstrate that for all coupling strengths of the half-filled, one-dimensional Kondo lattice (1) the spin excitations are local triplets, (2) the charge gap is greater than the spin gap, and (3) doping by Kondo holes induces residual spin-1/2 local moments. The implications of these results on a number of experiments and their relevance to the "Kondo insulators" will be discussed. © 1993 The American Physical Society.