Quasiparticles in the Kondo lattice model at partial fillings of the conduction band

TL;DR

This paper investigates the spectral properties of the one-dimensional Kondo lattice model at partial conduction band fillings, revealing the existence of spinpolarons and phase-dependent quasiparticle behaviors using advanced numerical methods.

Contribution

It provides the first detailed analysis of quasiparticle dispersion, lifetimes, and the Z-factor in the Kondo lattice model across different magnetic phases at partial fillings.

Findings

Evidence for spinpolaron existence at partial band fillings

Quasiparticle lifetime varies significantly between phases

Strong dependence of quasiparticle properties on quasimomentum

Abstract

We study the spectral properties of the one-dimensional Kondo lattice model as function of the exchange coupling, the band filling, and the quasimomentum in the ferromagnetic and paramagnetic phase. Using the density-matrix renormalization group method, we compute the dispersion relation of the quasiparticles, their lifetimes, and the Z-factor. As a main result, we provide evidence for the existence of the spinpolaron at partial band fillings. We find that the quasiparticle lifetime differs by orders of magnitude between the ferromagnetic and paramagnetic phase and depends strongly on the quasimomentum.