Long-lived Topological Flatband Excitons in Semiconductor Moiré Heterostructures: a Bosonic Kane-Mele Model Platform

Abstract

Moiré superlattices based on two-dimensional transition metal dichalcogenides (TMDs) have emerged as a highly versatile and fruitful platform for exploring correlated topological electronic phases. One of the most remarkable examples is the recently discovered fractional quantum anomalous Hall effect (FQAHE) under zero magnetic field. Here we propose a minimal structure that hosts long-lived excitons -- a ubiquitous bosonic excitation in TMD semiconductors -- with narrow topological bosonic bands. The nontrivial exciton topology originates from hybridization of moiré interlayer excitons, and is tunable by controlling twist angle and electric field. At small twist angle, the lowest exciton bands are isolated from higher energy bands and provide a solid-state realization of the bosonic Kane-Mele model with topological flatbands, which could potentially support the bosonic version of FQAHE.

Published version

References in corpus (20)

• High temperature fractional quantum Hall states
• Observation of Moiré Excitons in WSe2/WS2 Heterostructure Superlattices
• Fractional quantum Hall states at zero magnetic field
• Nearly-flat bands with nontrivial topology
• Resonantly hybridised excitons in moiré superlattices in van der Waals heterostructures
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• Van der Waals Heterostructure Polaritons with moiré-Induced Nonlinearity
• Mapping twist-tuned multiband topology in bilayer WSe${}_2$
• Moiré-Bose-Hubbard model for interlayer excitons in twisted transition metal dichalcogenide heterostructures
• Excitonic Mott insulator in a Bose-Fermi-Hubbard system of moiré ${\mathrm{WS}}_2$/${\mathrm{WSe}}_2$ heterobilayer
• Theory of tunable flux lattices in the homobilayer moiré of twisted and uniformly strained transition metal dichalcogenides
• Bosonic Fractional Quantum Hall States on a Finite Cylinder
• Tunable exciton valley-pseudospin orders in moiré Bose-Hubbard model

Cited by in corpus (7)

• Textured Exciton Insulators
• Collective optical properties of moiré excitons
• Förster valley-orbit coupling and topological lattice of hybrid moiré excitons
• Exciton fractional Chern insulators in moiré heterostructures
• Probing Quantum Anomalous Hall States in Twisted Bilayer WSe2 via Attractive Polaron Spectroscopy
• Engineering topological exciton structures in two-dimensional semiconductors by a periodic electrostatic potential
• Optical selection rules of topological excitons in flat bands