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Impact ionization can explain carrier multiplication in PbSe quantum dots.

A Franceschetti1, J M An, A Zunger

  • 1National Renewable Energy Laboratory, Golden, Colorado 80401, USA. alberto_franceschetti@nrel.gov

Nano Letters
|October 13, 2006
PubMed
Summary

Efficient carrier multiplication in quantum dots, crucial for solar cells, is explained by impact ionization. This mechanism, driven by Coulomb interactions, accounts for the observed rate and energy threshold without exotic theories.

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