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arXiv · 1406.3685

Superradiance and enhanced luminescence from ensembles of a few self-assembled quantum dots

Wildan Abdussalam·Paweł Machnikowski
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Abstract

We study the evolution of photoluminescence (PL) from homogeneous and inhomogeneous ensembles of a few coupled QDs. We discuss the relation between signals from a given QD ensemble under strong and weak excitation (full inversion and linear response regimes): A system homogeneous enough to manifest superradiant emission when strongly inverted shows a non-exponential decay of the PL signal under spatially coherent weak excitation. In an inhomogeneous ensemble the PL decay is always nearly exponential with a qualitatively different form of the time dependence in the two excitation regimes and with a higher rate under weak excitation.

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Wildan Abdussalam, Paweł Machnikowski. 2014-06-14. Superradiance and enhanced luminescence from ensembles of a few self-assembled quantum dots. https://doi.org/10.1103/physrevb.90.125307

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