High efficiency carrier multiplication in PbSe nanocrystals: implications for solar energy conversion.

@article{Schaller2004HighEC,
  title={High efficiency carrier multiplication in PbSe nanocrystals: implications for solar energy conversion.},
  author={Richard D. Schaller and Victor I. Klimov},
  journal={Physical review letters},
  year={2004},
  volume={92 18},
  pages={
          186601
        }
}
We demonstrate for the first time that impact ionization (II) (the inverse of Auger recombination) occurs with very high efficiency in semiconductor nanocrystals (NCs). Interband optical excitation of PbSe NCs at low pump intensities, for which less than one exciton is initially generated per NC on average, results in the formation of two or more excitons (carrier multiplication) when pump photon energies are more than 3 times the NC band gap energy. The generation of multiexcitons from a… 
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Recently, we demonstrated that PbSe nanocrystal quantum dots can efficiently produce multiple electron-hole pairs (excitons) in response to a single absorbed photon. To address the generality of this
Carrier Multiplication and Its Reduction by Photodoping in Colloidal InAs Quantum Dots: Addition/correction
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TLDR
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TLDR
Calculations of impact ionization rates, carrier multiplication yields, and solar-power conversion efficiencies in solar cells based on quantum dots (QDs) of a semimetal, α-Sn, and previous ones on PbSe and PbS QDs are presented.
Multiple exciton generation in PbSe nanorods
While multiple exciton generation (MEG) is known to occur more efficiently in semiconductor nanocrystals than in the bulk, the required energy threshold prevents visible photons from being utilized.
Enhanced multiple exciton generation in quasi-one-dimensional semiconductors.
TLDR
A significant enhancement of multiple exciton generation in PbSe quasi-one-dimensional semiconductors (nanorods) over zero-dimensional nanostructures (nanocrystals) is reported, characterized by a 2-fold increase in efficiency and reduction of the threshold energy to (2.23 ± 0.03)E(g), which approaches the theoretical limit of 2E( g).
Emergence of new materials for exploiting highly efficient carrier multiplication in photovoltaics
In conventional solar cell semiconductor materials (predominantly Si) photons with energy higher than the band gap initially generate hot electrons and holes, which subsequently cool down to the band
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