Multiexciton Lifetimes Reveal Triexciton Emission Pathway in CdSe Nanocrystals

• DOI: 10.1021/acs.nanolett.8b02080
• Publication Date: 2018-07-18T22:31:58Z
• Authors: Katherine E. Shul...; Thomas S. Bischof; Justin R. Caram; Hendrik Utzat; Igor Coropceanu; Lea Nienhaus; Moungi G. Bawendi
• Keywords: biexciton; 02 engineering and technology; Physical Chemistry; triexciton; Engineering; Auger recombination; Chemical Sciences; Physical Sciences; Nanotechnology; Semiconductor nanocrystal; single molecule spectroscopy; photon correlation; Nanoscience & Nanotechnology; 0210 nano-technology

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.