Ferroelectric Control of Interlayer Excitons in 3R-MoS$_{2}$ / MoSe$_{2}$ Heterostructures

TL;DR

This study demonstrates that ferroelectric domains in 3R-MoS$_2$/MoSe$_2$ heterostructures can control interlayer exciton energies, enabling electrical tuning and paving the way for ferroelectric optoelectronic devices.

Contribution

It provides experimental and theoretical evidence of ferroelectric domain influence on interlayer excitons in heterostructures, introducing a new method for exciton control.

Findings

Interlayer exciton energy varies with MoS$_2$ layer thickness.

Local ferroelectric domains affect exciton transition energies.

Gate voltage can electrically switch exciton energies via domain control.

Abstract

We investigate the interaction between interlayer excitons and ferroelectric domains in hBN-encapsulated 3R-MoS$_2$/MoSe$_2$ heterostructures, combining photoluminescence experiments with density functional theory and many-body Green's function calculations. Low-temperature photoluminescence spectroscopy reveals a strong redshift of the interlayer exciton energy with increasing MoS$_2$ layer thickness, attributed to band renormalization and dielectric effects. We observe local variations in exciton energy that correlate with local ferroelectric domain polarization of the 3R-MoS$_2$ layer, showcasing distinct domain-dependent interlayer exciton transition energies. Gate voltage experiments demonstrate that the interlayer exciton energy can be tuned by electrically induced domain switching. These results highlight the potential for interlayer exciton control by local ferroelectric order and establish a foundation for future ferroelectric optoelectronic devices based on van der Waals heterostructures.