Bosonization approach to the one-dimensional Kondo lattice model

TL;DR

This paper uses bosonization and conformal field theory to analyze the one-dimensional Kondo lattice model, revealing charge and spin gap openings at half-filling and a Luttinger liquid state away from half-filling, with potential divergences near half-filling.

Contribution

It provides a bosonization-based analysis of the Kondo lattice model, highlighting the behavior of gaps and susceptibilities across different electron densities.

Findings

Charge and spin gaps open at half-filling for antiferromagnetic coupling.

The system exhibits a Tomonaga-Luttinger liquid with a large Fermi surface away from half-filling.

Susceptibilities may diverge as electron density approaches half-filling.

Abstract

The one-dimensional Kondo lattice model is investigated by using bosonization techniques and conformal field theory. In the half-filled band, the charge and spin gaps open for the anti-ferromagnetic Kondo coupling. Away from half-filling, the paramagnetic metallic state is characterized by the fixed point of Tomonaga-Luttinger liquid with the {\it large} Fermi surface in accordance with known results. It is suggested that as the electron density approaches half-filling, both of spin and charge susceptibilities may show a divergence property.