Hybridization effect in the Falicov-Kimball model

TL;DR

This paper investigates how hybridization affects the electronic properties of the extended Falicov-Kimball model, revealing continuous valence transitions and discontinuous gap closures, consistent with experimental observations in SmB_6.

Contribution

It provides a detailed analysis of hybridization effects on valence transition and gap behavior using exact diagonalization, offering new insights into correlated electron systems.

Findings

Valence transition is continuous due to hybridization

Activation gap closes discontinuously

Results align with experimental data on SmB_6

Abstract

The extended Falicov-Kimball model which contains hybridization between localized level and conduction band has been studied using the exact diagonalization method. We obtain the single-particle density of states and the valency from this method and analyze the behaviors of valence transition and activation gap. We find that the valence transition is continuous due to hybridization, while the activation gap closes discontinuously. Moreover, the onset of the valence transition and the closing point of the activation gap mismatch each other. Our result is well consistent with the recent experiment on SmB_6.