Inclusion of intersite spatial correlations in the alloy analogy approach to the half-filled ionic Hubbard model

TL;DR

This paper investigates how intersite spatial correlations influence phase transitions in the half-filled ionic Hubbard model using a nonlocal coherent-potential approximation, revealing that such correlations promote metallic behavior.

Contribution

It introduces the inclusion of intersite spatial correlations into the alloy analogy approach for the ionic Hubbard model, enhancing understanding of phase transitions.

Findings

Intersite correlations expand the metallic phase region.

Spatial correlations affect the transition points between phases.

The approach improves modeling of correlated electron systems.

Abstract

Using the nonlocal coherent-potential approximation we study the effect of intersite spatial correlations on the transition from band insulator to metal as well as from metal to Mott insulator in the "alloy analogy" approach to the paramagnetic solution of the half-filled ionic Hubbard model. We find that intersite spatial correlations enhance the metallic phase.