Effects of the Nearest-Neighbour Coulomb Interactions on the Ground State of the Periodic Anderson Model

TL;DR

This paper investigates how nearest-neighbour Coulomb interactions influence the magnetic and non-magnetic ground states of the periodic Anderson model, revealing a critical interaction strength that destabilizes the magnetic state in the Kondo regime.

Contribution

It introduces a variational method to exactly evaluate the effects of NN Coulomb interactions on the ground states of the periodic Anderson model in infinite dimensions.

Findings

Magnetic ground state becomes unstable beyond a critical NN Coulomb interaction

Nearest-neighbour Coulomb interactions significantly affect correlated two-band models

The study highlights the importance of NN Coulomb interactions in ground state stability

Abstract

The magnetic and non-magnetic ground states of the periodic Anderson model with Coulomb interaction between $f$-electrons on the nearest-neighbour(NN) sites are investigated using a variational method, which gives exact calculation of the expectation values in the limit of infinite dimensions. It is shown that for a critical value of NN Coulomb interactions the magnetic ground state of the periodic Anderson model in the Kondo regime is unstable. Factors in terms of the physical processes responsible for instability of the magnetic ground state are also discussed. Our study indicates the importance of the NN Coulomb interactions for correlated two band models.