Ultra-narrow room-temperature emission from single CsPbBr<sub>3</sub> perovskite quantum dots.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 35546149.
- Also identified by DOI 10.1038/s41467-022-30016-0 and PMC identifier 9095639.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Semiconductor quantum dots have long been considered artificial atoms, but despite the overarching analogies in the strong energy-level quantization and the single-photon emission capability, their emission spectrum is far broader than typical atomic emission lines. Here, by using ab-initio molecular dynamics for simulating exciton-surface-phonon interactions in structurally dynamic CsPbBr<sub>3</sub> quantum dots, followed by single quantum dot optical spectroscopy, we demonstrate that emission line-broadening in these quantum dots is primarily governed by the coupling of excitons to low-energy surface phonons. Mild adjustments of the surface chemical composition allow for attaining much smaller emission linewidths of 35-65 meV (vs. initial values of 70-120 meV), which are on par with the best values known for structurally rigid, colloidal II-VI quantum dots (20-60 meV). Ultra-narrow emission at room-temperature is desired for conventional light-emitting devices and paramount for emerging quantum light sources.