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A novel site-controlled quantum dot system with high uniformity and narrow excitonic emission

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 نشر من قبل Lorenzo Mereni
 تاريخ النشر 2010
  مجال البحث فيزياء
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We report on the optical properties of a newly developed site-controlled InGaAs Dots in GaAs barriers grown in pre-patterned pyramidal recesses by metalorganic vapour phase epitaxy. The inhomogeneous broadening of excitonic emission from an ensemble of quantum dots is found to be extremely narrow, with a standard deviation of 1.19 meV. A dramatic improvement in the spectral purity of emission lines from individual dots is also reported (18-30 ueV) when compared to the state-of-the-art for site controlled quantum dots.



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