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arXiv · 1207.1237

In-plane radiative recombination channel of a dark exciton in self-assembled quantum dots

Tomasz Smoleński·Tomasz Kazimierczuk·Mateusz Goryca·Tomasz Jakubczyk·Łukasz Kłopotowski·Łukasz Cywiński·Piotr Wojnar·Andrzej Golnik·Piotr Kossacki
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Abstract

We demonstrate evidence for a radiative recombination channel of dark excitons in self-assembled quantum dots. This channel is due to a light hole admixture in the excitonic ground state. Its presence was experimentally confirmed by a direct observation of the dark exciton photoluminescence from a cleaved edge of the sample. The polarization resolved measurements revealed that a photon created from the dark exciton recombination is emitted only in the direction perpendicular to the growth axis. Strong correlation between the dark exciton lifetime and the in-plane hole g-factor enabled us to show that the radiative recombination is a dominant decay channel of the dark excitons in CdTe/ZnTe quantum dots.

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Tomasz Smoleński, Tomasz Kazimierczuk, Mateusz Goryca, Tomasz Jakubczyk, Łukasz Kłopotowski, Łukasz Cywiński, Piotr Wojnar, Andrzej Golnik, Piotr Kossacki. 2013-01-03. In-plane radiative recombination channel of a dark exciton in self-assembled quantum dots. https://doi.org/10.1103/physrevb.86.241305

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