GaInNAsSb based long-wavelength lasers

Dilute nitride GaInNAs alloys grown on GaAs have quickly become excellent candidate materials for lower cost 1.3 μm vertical cavity surface emitting lasers (VCSELs) and high power edge emitting lasers. Despite the relative immaturity and challenges of this new materials system the results have been very promising. The major remaining challenges include the limited solubility of nitrogen in GaAs, non-radiative defects that may be caused by nitrogen incorporation, and phase segregation at high In compositions. A new component, Sb, has been added in order to improve epitaxial growth and optical properties at wavelengths longer than 1.3 μm. By adding Sb to the alloy, luminescence has been greatly enhanced between 1.3-1.6 μm where normally poor quality material results. Lasers fabricated from this new pentenary alloy have produced the lowest threshold lasers operating beyond 1.4 μm on GaAs. Progress and the remaining challenges of this materials system are described.