Regensburg 2019 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
HL: Fachverband Halbleiterphysik
HL 39: Quantum dots and wires: Optical properties I
HL 39.6: Vortrag
Donnerstag, 4. April 2019, 10:45–11:00, H34
Interpreting ensemble photoluminescence of InAs quantum dots coupled to a Fermi reservoir — •Alexander Rolf Korsch1, Giang Nam Nguyen1, Marcel Schmidt1, Carsten Ebler1, Sascha René Valentin1, Pia Lochner1,2, Charlotte Rothfuchs1, Andreas Dirk Wieck1, and Arne Ludwig1 — 1Lehrstuhl für Angewandte Festkörperphysik, Ruhr-Universität Bochum, Germany — 2Fakultät für Physik and CENIDE, Universität Duisburg-Essen, Germany
Self-assembled InAs quantum dots in semiconductor heterostructures enabled the realization of new technologies such as quantum dot lasers or single photon sources. For many applications, temperature stability of the emission properties is desired and tunability of energy levels by an applied voltage is required [1].
We present anomalous behavior of temperature-dependent photoluminescence (PL) measurements on InAs quantum dot ensembles coupled to an electron reservoir. When negative gate voltages are applied to the sample, an anomalous initial increase of the integrated PL signal intensity with rising temperature is observed for the ground state and first excited state emission peaks. The anomalous temperature-dependence is caused by electrons tunneling from the electron reservoir to the quantum dots enhancing the PL signal. This effect can be accounted for by a modified Arrhenius model. PL measurements at 77 K are further compared to capacitance-voltage spectroscopy measurements on the same sample supporting the proposed interpretation.
[1] Ediger et al., Nature Physics 3, 774 (2007).