Berlin 2008 – wissenschaftliches Programm
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HL: Fachverband Halbleiterphysik
HL 1: Invited Talk Kümmell
HL 1.1: Hauptvortrag
Montag, 25. Februar 2008, 09:30–10:15, ER 270
Electrically driven single quantum dot emitter operating at room temperature — •Tilmar Kümmell1, Robert Arians1, Gerd Bacher1, Arne Gust2, Carsten Kruse2, and Detlef Hommel2 — 1Werkstoffe der Elektrotechnik, Universität Duisburg-Essen, Duisburg — 2Institut für Festkörperphysik, Universität Bremen, Bremen
Single self-organized semiconductor quantum dots are regarded as one of the most interesting approaches for realizing single photon sources. Although several device concepts have been presented, their applicability was limited to low temperatures up to now. Here, we present electrically driven emission from one single quantum dot at room temperature.
The single quantum dot emitter is based on epitaxially grown CdSe/ZnSSe quantum dots. By sandwiching the active area between MgS barriers, access to room temperature photoluminescence from a single quantum dot became possible [1]. Choosing an appropriate thickness, the MgS barriers do not hamper an electrically driven operation. Embedding the quantum dot active layer into a p-i-n diode, we succeeded in obtaining room temperature electroluminescence from one single quantum dot at a voltage of U = 2.6 V. We observe no significant loss of quantum efficiency with respect to 4 K. The emission linewidth at T = 300 K is about 25 meV and is thus not exceeding the biexciton binding energy, a crucial point for an operation as a single photon emitter.
[1] R. Arians et. al, Appl. Phys. Lett. 90, 101114 (2007)