Phases and Density of States in a Generalized Su-Schrieffer-Heeger Model

TL;DR

This paper investigates a generalized 2D Su-Schrieffer-Heeger model, revealing inhomogeneous phases with topological, ordered, or glassy features, all exhibiting a Fermi level gap, expanding understanding of complex quantum phases.

Contribution

It introduces a comprehensive analysis of inhomogeneous phases in a generalized SSH model, highlighting their topological and structural properties beyond previous studies.

Findings

Discovery of spatially inhomogeneous phases away from half-filling

Identification of topological flux structures and large unit cell bond orders

Universal presence of a gap at the Fermi level in all phases

Abstract

Self-consistent solutions to a generalized Su-Schrieffer-Heeger model on a 2-dimensional square lattice are investigated. Away from half-filling, spatially inhomogeneous phases are found. Those phases may have topological structures on the flux order, large unit cell bond order, localized bipolarons, or they are simply short-range ordered and glassy. They have an universal feature of always possessing a gap at the Fermi level.