Regensburg 2019 – wissenschaftliches Programm
HL 45.46: Poster
Donnerstag, 4. April 2019, 18:30–21:00, Poster E
Nonequilibrium Resonance in Quantum Dots without Electronic Wetting Layer States — •Ibrahim A. Engin, Ismail Bölükbasi, Sven Scholz, Andreas D. Wieck, and Arne Ludwig — Lehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität Bochum, D-44780 Bochum, Germany
Self assambled InAs quantum dots (SAQD) proved promising semiconductor structures as single photon sources.
We investigate electronic resonances in illuminated InAs SAQDs by using C(V)-spectroscopy. With constant illumination of SAQDs metastable hole states can be created . Furthermore, non-equilibrium states have been observed by increased illumination or tunnel barrier length .
SAQDs are grown inevitably with a wetting layer (WL), which interferes with the SAQD observation by affecting the photon emission spectrum of quantum dots. Here we modify the growth of SAQDs by adding a monolayer of AlAs on the quantum dots to suppress electronic WL-states  by more than 30dB and study non-equilibrium electron resonances.
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 Löbl, M. et al., "Excitons in InGaAs Quantum Dots without Electron Wetting Layer States", eprint arXiv:1810.00891 (2018)