Charge Density Waves in a Doped Kondo Chain

We show that charge density waves (CDWs) exist in the ground state of the one-dimensional Kondo lattice model at the filling of n=0.75 with a finite charge gap, while most of the doped phase is metallic. Based on our numerical results using the density matrix renormalization group method, we separate the CDW phase from the paramagnetic phase previously known as the Tomonaga-Luttinger liquid. The emergence of this phase serves as an example of CDW induced without repulsive interaction between electrons, and enriches the phase diagram of the 1D Kondo Lattice model.