Observation of biexciton emission from single semiconductor nanoplatelets

Quasi-two-dimensional semiconductor nanoplatelets (NPLs) are intriguing systems for studying the influence of Auger recombination processes on the multiexciton emission efficiencies in the weak in-plane confinement regime. We investigate CdSe/CdS core/shell NPLs using cryogenic temperature single particle spectroscopy and observe bright biexciton emission at high excitation powers. The average binding energy of the biexcitons is determined to be 16.5 meV. The observed switching between the biexciton and trion states indicates charging-decharging dynamics of the NPLs mediated by the Auger ionization process. These findings are highly relevant for harvesting efficient biexciton emission for energy, lighting, and quantum applications.

Automated summary

Bright biexciton emission at high excitation powers was observed in CdSe/CdS core/shell NPLs, with an average binding energy of 16.5 meV, indicating charging-decharging dynamics of the NPLs mediated by the Auger ionization process. These findings are important for efficient biexciton emission in energy, lighting, and quantum applications.