Charge Kondo Effect and Superconductivity in the Falikov-Kimball model with the Pair Hopping

TL;DR

This paper investigates the charge Kondo effect and superconductivity in a modified Falikov-Kimball model, revealing the persistence of the Kondo state at zero temperature and its competition with other phases.

Contribution

It introduces the pair hopping term into the Falikov-Kimball model and analyzes its effects using dynamical mean-field theory and quantum Monte Carlo methods.

Findings

Charge Kondo state persists at zero temperature

Charge order and s-wave superconductivity compete with the Kondo state

Interorbital repulsion influences the superconducting phase

Abstract

We study the Falikov-Kimball model with the pair hopping between the conduction and localized bands to discuss how the charge Kondo effect is realized. By combining dynamical mean-field theory with the continuous time quantum Monte Carlo method, we clarify that the charge Kondo state survives even at zero temperature and this competes with the charge ordered and s-wave superconducting states. The role of the interorbital repulsion for the superconducting state is also addressed.