Hamburg 2009 – scientific programme
Parts | Days | Selection | Search | Downloads | Help
Q: Fachverband Quantenoptik und Photonik
Q 61: Laserentwicklung: Halbleiterlaser
Q 61.2: Talk
Friday, March 6, 2009, 10:45–11:00, VMP 8 HS
Spectro-Temporal Gain-Switching Dynamics of a InGaAs Quantum-Dot Laser — •Lukas Drzewietzki1, Stefan Breuer1, George The2, Mariangela Gioannini2, Wolfgang Elsäßer1, Ivo Montrosset2, Mark Hopkinson3, and Michael Krakowski4 — 1Institut für Angewandte Physik, TU-Darmstadt, Schloßgartenstr. 7, 64289 Darmstadt, Germany — 2Dipartimento di Elettronica, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino — 3Department of Electronic and Electrical Engineering, University of Sheffield, Sheffield S1 3JD, United Kingdom — 4Alcatel-Thales III-V Lab, Route de Nozay, 91461 Marcoussis, France
Self-assembled quantum dots (QD) are a distribution of zero-dimensional structures and provide discrete energy levels. Implemented as the active medium in a diode laser they lead to improved characteristics compared to bulk or quantum-well devices like low threshold current and high gain bandwidth. Due to their multiple discrete population levels QD-Lasers (QDL) are also able to perform two-state lasing. We present spectrally resolved picosecond measurements of the gain-switching dynamics of a QD-laser at different temperatures and current steps. Also spectrally resolved continuous-wave (CW) measurements are carried out. We report on the existence and interaction of the ground and excited state (GS, ES) emission in CW and pulsed operation. Both operation regimes are compared and the influence of the operation parameters on the emission dynamics are discussed. The presented measurements are compared to numerical simulations obtained with a multi-population model.