Dirac zeros in an orbital selective Mott phase: Green's function Berry curvature and flux quantization

TL;DR

This paper explores the topological properties of Green's function zeros in an orbital-selective Mott phase, revealing quantized Berry flux and Dirac zeros, which offer new insights into strongly correlated metallic systems.

Contribution

It introduces the concept of Dirac zeros and demonstrates their quantized Berry flux in an orbital-selective Mott phase, advancing understanding of topology in correlated metals.

Findings

Symmetry protected crossing of Green's function zeros in OSMP.

Quantized Berry flux associated with zero crossings.

Introduction of Dirac zeros as a topological diagnostic in correlated metals.

Abstract

How electronic topology develops in strongly correlated systems represents a fundamental challenge in the field of quantum materials. Recent studies have advanced the characterization and diagnosis of topology in Mott insulators whose underlying electronic structure is topologically nontrivial, through ``Green's function zeros". However, their counterparts in metallic systems have yet to be explored. Here, we address this problem in an orbital-selective Mott phase (OSMP), which is of extensive interest to a variety of strongly correlated systems with a short-range Coulomb repulsion. We demonstrate symmetry protected crossing of the zeros in an OSMP. Utilizing the concept of Green's function Berry curvature, we show that the zero crossing has a quantized Berry flux. The resulting notion of Dirac zeros provides a window into the largely hidden landscape of topological zeros in strongly correlated metallic systems and, moreover, opens up a means to diagnose strongly correlated topology in new materials classes.