Dresden 2014 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
HL: Fachverband Halbleiterphysik
HL 70: Semiconductor laser I: VECSEL and cascade lasers
HL 70.9: Vortrag
Mittwoch, 2. April 2014, 17:00–17:15, POT 112
Emission intensity modulation of a VCSEL by ultrafast acoustics — •Jan Tepper1, Thomas Czerniuk1, Christian Brüggemann1, Sebastian Brodbeck2, Christian Schneider2, Martin Kamp2, Sven Höfling2, Boris Glavin3, Dimitri Yakovlev1,4, Andrey Akimov4,5, and Manfred Bayer1 — 1Experimentelle Physik 2a, TU Dortmund, Dortmund, Germany — 2Technische Physik, Universität Würzburg, Würzburg, Germany — 3V. E. Lashkaryov Institute of Semiconductor Physics, Kiev, Ukraine — 4A. F. Ioffe Physical-Technical Institute, Russian Academy of Sciences, St. Petersburg, Russia — 5School of Physics and Astronomy, University of Nottingham, Nottingham, United Kingdom
We report an ultrafast intensity modulation of a VCSEL's laser emission of up to 50% peak-to-peak by shifting the active medium's spectral profile using an acoustic strain pulse.
The sample under investigation is an AlAs/GaAs based microcavity, which inhabits quantum wells as the active medium. Its emission intensity strongly depends on how well the active medium's wavelength matches the cavity mode. By using high energy femtosecond laser pulses, we generate a strain pulse travelling through the sample. This strain pulse subsequently reaches the QWs and alters their band gap, which leads to an emission intensity modulation with an amplitude of 50% from peak to peak. Due to the small spatial separation of the QWs, the corresponding modulation frequencies lie in the THz regime. Qualitatively, the results can be described by rate equations in which the strain is treated as a perturbation of the laser's gain.