Dresden 2014 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe

HL: Fachverband Halbleiterphysik

HL 30: Poster: Quantum dots and wires: Preparation, characterization, optical properties and transport

HL 30.3: Poster

Montag, 31. März 2014, 17:00–20:00, P2

Characterization of InP-quantum dots in AlGaInP for integration in vertical-cavity surface-emitting lasers as active medium — •Sergey Gelhorn, Susanne Weidenfeld, Thomas Schwarzbäck, Roman Bek, Christian Keßler, Michael Jetter, and Peter Michler — Institut für Halbleiteroptik und Funktionelle Grenzflächen and Research Center SCoPE, Universität Stuttgart, Allmandring 3, 70569 Stuttgart, Germany

With reduction of the dimensionality of the laser active media, differential gain increases which brings advantages like simultaneous low threshold current and high modulation bandwidth. Quantum dots (QDs) are zero-dimensional structures and their usage as laser active media can provide a temperature independent laser threshold current [1]. However, if the difference between QD-energy and bandgap of the surrounding barrier is small, carriers can be thermally excited from QD in the barrier. Therefore thermal stability of QD-layers needs to be controlled to allow their integration as active medium in a laser device. We report about spectral and thermal characterization of InP-QD layers, which were integrated in AlGaInP-barrier during metal-organic vapor-phase epitaxy. The integration of stacked InP-QD layers in vertical-cavity surface-emitting lasers is shown, where we took care that the averaged emission energy properly match the energy of the optical resonator. Finally, experiments to increase the energetic confinement of the InP-QDs are presented.

[1] Y. Arakawa and H. Sakaki, Appl. Phys. Lett. 40, 939 (1982)