Peak External Photocurrent Quantum Efficiency Exceeding 100% via MEG in a Quantum Dot Solar Cell

@article{Semonin2011PeakEP,
  title={Peak External Photocurrent Quantum Efficiency Exceeding 100\% via MEG in a Quantum Dot Solar Cell},
  author={Octavi E. Semonin and Joseph M. Luther and Sukgeun Choi and Hsiang‐Yu Chen and Jianbo Gao and Arthur J. Nozik and Matthew C. Beard},
  journal={Science},
  year={2011},
  volume={334},
  pages={1530 - 1533}
}
An experimental solar cell productively uses an extra fraction of high-energy light typically lost as heat. Multiple exciton generation (MEG) is a process that can occur in semiconductor nanocrystals, or quantum dots (QDs), whereby absorption of a photon bearing at least twice the bandgap energy produces two or more electron-hole pairs. Here, we report on photocurrent enhancement arising from MEG in lead selenide (PbSe) QD-based solar cells, as manifested by an external quantum efficiency (the… 
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