The boom in fiber-optic communications has caused a high demand for GaAs-based lasers in the 1.3-1.6-/spl mu/m range. This has led to the introduction of small amounts of nitrogen into InGaAs to reduce the bandgap sufficiently, resulting in a new material that is lattice matched to GaAs. More recently, the addition of Sb has allowed further reduction of the bandgap, leading to the first demonstration of 1.5-/spl mu/m GaAs-based lasers by the authors. Additional work has focused on the use of GaAs, GaNAs, and now GaNAsSb barriers as cladding for GaInNAsSb quantum wells. We present the results of photoluminescence, as well as in-plane lasers studies, made with these combinations of materials. With GaNAs or GaNAsSb barriers, the blue shift due to post-growth annealing is suppressed, and longer wavelength laser emission is achieved. Long wavelength luminescence out to 1.6 /spl mu/m from GaInNAsSb quantum wells, with GaNAsSb barriers, was observed. In-plane lasers from these samples yielded lasers operating out to 1.49 /spl mu/m, a minimum threshold current density of 500 A/cm/sup 2/ per quantum well, a maximum differential quantum efficiency of 75%, and pulsed power up to 350 mW at room temperature.
Read full abstract