  Employing the density matrix renormalization group method and strong-coupling
perturbation theory, we study the phase diagram of the SU(2)xSU(2) Kondo
lattice model in one dimension. We show that, at quarter filling, the system
can exist in two phases depending on the coupling strength. The weak-coupling
phase is dominated by RKKY exchange correlations while the strong-coupling
phase is characterized by strong antiferromagnetic correlations of the channel
degree of freedom. These two phases are separated by a quantum critical point.
For conduction-band fillings of less than one quarter, we find a paramagnetic
metallic phase at weak coupling and a ferromagnetic phase at moderate to strong
coupling.
