Emission dynamics of a (GaIn)(NAs) vertical-cavity surface-emitting laser

Vertical-cavity surface-emitting lasers (VCSELs) are interesting devices for applications in high speed optical fiber networks. Therefore the development of VCSEL structures for the generation of short optical pulses at emission wavelengths in the optical-fiber windows of 1.3 or 1.55 µm is important. The InGaAsP-InP material system which is most common for edge emitters in this long wavelength regime suffers from the lack of epitaxial layers with high refractive index difference. Thus an appropriate distributed Bragg Reflector (DBR) can only be obtained with a large number of mirror layers. This involves not only a high resistance in electrically pumped devices, but also increases the effective cavity length which results in slower dynamics, due to longer photon lifetimes. In contrast, GaInNAs has been demonstrated recently as a very attractive active material for the long wavelength regime. It can be grown lattice matched on GaAs and thus allows to use well established GaAs-AlAs DBRs. We have realized a microcavity laser with GaInNAs quantum wells with a high enough content of nitrogen to reach wavelengths near 1.28 µm. Here we present first results on the picosecond dynamics of a GaInNAs VCSEL-structure.