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Enhanced spontaneous emission in a photonic crystal light-emitting diode

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 نشر من قبل Annamaria Gerardino
 تاريخ النشر 2008
  مجال البحث فيزياء
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We report direct evidence of enhanced spontaneous emission in a photonic crystal (PhC) light-emitting diode. The device consists of p-i-n heterojunction embedded in a suspended membrane, comprising a layer of self-assembled quantum dots. Current is injected laterally from the periphery to the center of the PhC. A well-isolated emission peak at 1300nm from the PhC cavity mode is observed, and the enhancement of the spontaneous emission rate is clearly evidenced by time-resolved electroluminescence measurements, showing that our diode switches off in a time shorter than the bulk radiative and nonradiative lifetimes



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