Auger Recombination of multiexcitons has long been an obstacle to the many optical applications of colloidal semiconductor quantum dots (QDs). Here, we present a quantum shell geometry that is capable of suppressing the fast Auger recombination of multi-excitons, resulting in extraordinary improvements to optical gain and biexciton lifetime. These Nanoshell quantum dots have shown biexciton lifetimes ranging from 5.1 to 10.5 ns with biexciton quantum yields up to 84%. In addition to their record setting biexciton lifetimes, our nanoshell quantum dots have also demonstrated significant gain lifetimes, over 3 ns. The realization of these optical properties was demonstrated by amplified stimulated emission (ASE) measurements of spin-coated thin films showing both single-exciton and multi-exciton ASE at thersholds as low as 9.52 uJ/cm2. Based on these characteristics, we expect that colloidal nanoshell QDs will emerge as a promising class of colloidal semiconductor QDs for the development of lasing and light-emitting applications.

Nanoshell quantum dots for light emitting applications

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.