Correlation exponent K_ρ of the one-dimensional Kondo lattice model

We present results for the correlation exponent K_ρ of the Tomonaga-Luttinger liquid description of the one-dimensional Kondo lattice as a function of conduction-electron density and coupling constant. K_ρ is obtained from the first derivative of the Fourier transform of the charge-charge correlation function. We also show that the spin correlation function can only be described in this picture if we include logarithmic corrections, a feature that had been previously overlooked. A consistent description of both charge and spin sectors is then obtained. Finally, we show evidence that the spin sector of the dimerized phase at quarter-filling is gapless.