Exciton-polaritons in transition-metal dichalcogenides and their direct excitation via energy transfer

TL;DR

This paper develops a semi-classical model for exciton-polaritons in monolayer TMDs, highlighting their dispersion, decay, and excitation via energy transfer from quantum emitters, with implications for optoelectronic applications.

Contribution

It introduces a new semi-classical framework for intrinsic exciton-polaritons in monolayer TMDs, accounting for dispersion, decay, and environmental effects.

Findings

Long-range interactions affect polariton dispersion and decay.

Exciton-polaritons can be efficiently excited via energy transfer from quantum dots.

The model incorporates dielectric environment effects.

Abstract

Excitons, composite electron-hole quasiparticles, are known to play an important role in optoelectronic phenomena in many semiconducting materials. Recent experiments and theory indicate that the band-gap optics of the newly discovered monolayer transition-metal dichalcogenides (TMDs) is dominated by tightly bound valley excitons. The strong interaction of excitons with long-range electromagnetic fields in these 2D systems can significantly affect their intrinsic properties. Here, we develop a semi-classical framework for intrinsic exciton-polaritons in monolayer TMDs that treats their dispersion and radiative decay on the same footing and can incorporate effects of the dielectric environment. It is demonstrated how both inter- and intra-valley long-range interactions influence the dispersion and decay of the polaritonic eigenstates. We also show that exciton-polaritons can be efficiently excited via resonance energy transfer from quantum emitters such as quantum dots, which may be useful for various applications.