Electronic properties, correlated topology and Green's function zeros

TL;DR

This paper investigates the role of Green's function zeros in correlated topological insulators, demonstrating their contribution to measurable properties in an exactly solvable Mott insulator model, and clarifying their physical significance.

Contribution

It provides an exact analysis showing how Green's function zeros influence physical observables in correlated topological systems, clarifying their role in strongly correlated insulators.

Findings

Green's function zeros contribute to measurable correlation functions.

Physical properties are robust to chemical potential variations within the Mott gap.

The study clarifies the role of zeros in correlated topology without inconsistencies.

Abstract

There is extensive current interest about electronic topology in correlated settings. In strongly correlated systems, contours of Green's function zeros may develop in frequency-momentum space, and their role in correlated topology has increasingly been recognized. However, whether and how the zeros contribute to electronic properties is a matter of uncertainty. Here we address the issue in an exactly solvable model for Mott insulator. We show that the Green's function zeros contribute to several physically measurable correlation functions, in a way that does not run into inconsistencies. In particular, the physical properties remain robust to chemical potential variations up to the Mott gap as it should be based on general considerations. Our work sets the stage for further understandings on the rich interplay among topology, symmetry and strong correlations.