Strong exciton-photon coupling with colloidal quantum dots in a tuneable microcavity

TL;DR

This paper demonstrates room temperature strong exciton-photon coupling in colloidal quantum dots within a tuneable microcavity, achieving high coupling strength and highlighting potential for practical photonic and optoelectronic applications.

Contribution

It reports the first demonstration of strong coupling with colloidal quantum dots in a tuneable microcavity at room temperature, with a coupling strength of 154 meV.

Findings

Achieved strong exciton-photon coupling at room temperature.

Observed a Rabi splitting dependent on cavity detuning.

Demonstrated high quantum yields and photostability of quantum dots.

Abstract

Polariton emission from optical cavities integrated with various luminophores has been extensively studied recently due to the wide variety of possible applications in photonics, particularly promising in terms of fabrication of low-threshold sources of coherent emission. Tuneable microcavities allow extensive investigation of the photophysical properties of matter placed inside the cavity by deterministically changing the coupling strength and controllable switching from weak to strong and ultra-strong coupling regimes. Here we demonstrate room temperature strong coupling of exciton transitions in CdSe/ZnS/CdS/ZnS colloidal quantum dots with the optical modes of a tuneable low-mode-volume microcavity. Strong coupling is evidenced by a large Rabi splitting of the photoluminescence spectra depending on the detuning of the microcavity. A coupling strength of 154 meV has been achieved. High quantum yields, excellent photostability, and scalability of fabrication of QDs paves the way to practical applications of coupled systems based on colloidal QDs in photonics, optoelectronics, and sensing.