Multiexciton Lifetimes Reveal Triexciton Emission Pathway in CdSe Nanocrystals

Nano Lett. 2018 Aug 8;18(8):5153-5158. doi: 10.1021/acs.nanolett.8b02080. Epub 2018 Jul 17.

Abstract

Multiexcitons in emerging semiconducting nanomaterials play a critical role in potential optoelectronic and quantum computational devices. We describe photon resolved single molecule methods to directly probe the dynamics of biexcitons and triexcitons in colloidal CdSe quantum dots. We confirm that biexcitons emit from a spin-correlated state, consistent with statistical scaling. Contrary to current understanding, we find that triexciton emission is dominated by band-edge 1Se1S3/2 recombination rather than the higher energy 1Pe1P3/2 recombination.

Keywords: Auger recombination; Semiconductor nanocrystal; biexciton; photon correlation; single molecule spectroscopy; triexciton.

Publication types

  • Research Support, Non-U.S. Gov't