Emergence of Topological Non-Fermi Liquid Phases in a Modified Su-Schrieffer-Heeger Chain with Long-Range Interactions

TL;DR

This paper uncovers topological non-Fermi liquid phases in a modified SSH chain with long-range interactions, revealing new topological states and electronic properties beyond traditional Fermi liquid theory.

Contribution

It introduces a topological non-Fermi liquid phase in a long-range interacting SSH model, demonstrating novel topological and electronic features through exact diagonalization.

Findings

Identification of topological and trivial NFL phases via many-body Zak phases

Observation of non-quasiparticle spectral features in the density of states

Manifestation of unique polarization characteristics in the topological NFL state

Abstract

In this study, we investigate the emergence of a topological non-Fermi liquid (NFL) phase in a modified Su-Schrieffer-Heeger (SSH) chain model subjected to long-range interactions characterized by the Hatsugai-Kohmoto (HK) model. While Fermi liquid theory has been instrumental in understanding low temperature properties of metals, it fails to account for the complex behaviors exhibited by strongly correlated systems, where interactions lead to emergent phenomena such as non-Fermi liquid behavior. Our analysis reveals that the SSH-HK model supports a rich ground state phase diagram, exhibiting distinct NFL phases marked by many body Zak phases of $2\pi$ and $0$, corresponding to topological and trivial NFL states, respectively. We demonstrate that the topological NFL state manifests unique electronic polarization characteristics akin to those in the non-interacting SSH model. Through exact diagonalization of the interacting SSH-HK Hamiltonian, we explore the spectral functions and density of states, revealing significant departures from traditional quasiparticle behavior in various particle number sectors. Our findings extend the understanding of topological non-Fermi liquids and their potential implications for high-temperature superconductivity and other correlated electron systems, highlighting the intricate interplay between topology and strong electron correlations.