Doped Kondo chain a heavy Luttinger liquid

The doped 1D Kondo Lattice describes complex competition between itinerant and magnetic ordering The numerically computed wave vector dependent charge and spin susceptibilities give insights into its low energy properties Similar to the prediction of the large N approximation gapless spin and charge modes appear at the large Fermi wave vector The highly suppressed spin velocity is a manifestation of heavy Luttinger liquid quasiparticles A low energy hybridization gap is detected at the small conduction band Fermi wave vector In contrast to the exponential suppression of the Fermi velocity in the large N approximation we fit the spin velocity by a density dependent power law of the Kondo coupling The differences between the large N theory and our numerical results are associated with the emergent magnetic Ruderman Kittel Kasuya Yosida interactions