Ultra-narrow emission from single GaAs self-assembled quantum dots grown by droplet epitaxy.
We realized ultra-narrow excitonic emission from single GaAs/AlGaAs quantum dots (QDs) grown by a refined droplet epitaxy technique. We found that uncapped quantum dots can be annealed at 400 degrees C without major changes in their morphology, thus enabling an AlGaAs capping layer to be grown at that temperature. Consequently, we demonstrate a fourfold reduction of the linewidth of the emission together with an increased recombination lifetime, compared to the conventional droplet epitaxial QDs. The averaged linewidth of neutral excitons measured by micro-photoluminescence on single quantum dots was around 35 microeV.
Mano
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Quantum Dot Research Center, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-0047, Japan. MANO.Takaaki@nims.go.jp
Abbarchi
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Kuroda
T
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Mastrandrea
C A
CA
Vinattieri
A
A
Sanguinetti
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Sakoda
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Gurioli
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