Interplay of localized and itinerant behavior in the one-dimensional Kondo-Heisenberg model

TL;DR

This study uses the density matrix renormalization group method to explore the dual localized and itinerant behavior of spins in the one-dimensional Kondo-Heisenberg model, revealing a microscopic basis for the two-fluid behavior in heavy electron materials.

Contribution

It introduces a microscopic definition of hybridization that captures partial itinerancy and demonstrates the coexistence of localized and itinerant behaviors in a one-dimensional model.

Findings

Signatures of simultaneous localized and itinerant behaviors of local spins.

A proposed microscopic hybridization parameter measuring partial itinerancy.

Support for the dual nature of f-electrons and two-fluid behavior in heavy electron systems.

Abstract

We use the density matrix renormalization group method to study the interplay of the localized and itinerant behaviors in the one-dimensional Kondo-Heisenberg model. We find signatures of simultaneously localized and itinerant behaviors of the local spins and attribute this duality to their simultaneous entanglement within the spin chain and with conduction electrons due to incomplete hybridization. We propose a microscopic definition of the hybridization parameter that measures this "partial" itinerancy. Our results provide a microscopic support for the dual nature of f-electrons and the resulting two-fluid behavior widely observed in heavy electron materials.