SINGLE-PARTICLE EXCITATIONS OF THE KONDO-LATTICE

We present a simple theory for the description of the single-particle excitations of the Kondo lattice model. We derive an effective Hamilto nian that describes the coherent propagation of single-particle-like f luctuations on a strong-coupling ground state. Even for f electrons th at are replaced by Kondo spins, the resulting spectral function obeys the Luttinger theorem including the f electrons, and our calculation r eproduces the complicated evolution of the spectral function with elec tron density seen in numerical studies.