Topological stripe state in an extended Fermi-Hubbard model

TL;DR

This paper reports the discovery of a topological stripe state in an extended Fermi-Hubbard model, featuring chiral edge states and potential for realization in ultracold atom quantum simulators.

Contribution

It introduces a novel topological stripe phase induced by interactions, with analysis of its edge states and a proposed experimental detection method.

Findings

Topological stripe phase appears around half-filling.

Chiral edge states are present on domain walls.

Quantized charge transfer confirms topological nature.

Abstract

Interaction-induced topological systems have attracted a growing interest for their exotic properties going beyond the single-particle picture of topological insulators. In particular, the interplay between strong correlations and finite doping can give rise to nonhomogeneous solutions that break the translational symmetry. In this work, we report the appearance of a topological stripe state in an interaction-induced Chern insulator around half-filling. In contrast to similar stripe phases in nontopological systems, here we observe the appearance of chiral edge states on top of the domain wall. Furthermore, we characterize their topological nature by analyzing the quantized transferred charge of the domains in a pumping scheme. Finally, we focus on aspects relevant to observing such phases in state-of-the-art quantum simulators of ultracold atoms in optical lattices. In particular, we propose an adiabatic state preparation protocol and a detection scheme of the topology of the system in real space.