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Absorption enhancement in amorphous silicon photonic crystals for thin film photovoltaic solar cells

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 نشر من قبل Ounsi El Daif
 تاريخ النشر 2009
  مجال البحث فيزياء
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We report on very high enhancement of thin layers absorption through band-engineering of a photonic crystal structure. We realized amorphous silicon (aSi) photonic crystals, where slow light modes improve absorption efficiency. We show through simulation that an increase of the absorption by a factor of 1.5 is expected for a film of aSi. The proposal is then validated by an experimental demonstration, showing an important increase of the absorption of a layer of aSi over a spectral range of 0.32-0.76 microns.



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