Lattice path integral approach to the one-dimensional Kondo model

An integrable Anderson-like impurity model in a correlated host is derived from a gl (2/1)-symmetric transfer matrix by means of the quantum-inverse-scattering-method (QISM). Using the quantum transfer matrix technique, free energy contributions of both the bulk and the impurity are calculated exactly. As a special case, the limit of a localized moment in a free bulk (Kondo limit) is performed in the Hamiltonian and in the free energy. In this case, high- and low-temperature scales are calculated with high accuracy.