Optically pumped type-II antimonide mid-IR lasers with integrated absorber layers

We report on optically-pumped mid-infrared (3.4 - 4.5 /spl mu/m) lasers based on InAs/InGaSb/InAs type-II quantum wells that are periodically inserted into the InGaAsSb waveguide designed to absorb the 1.85 /spl mu/m pump radiation. The integrated absorber layers allow the decoupling of pump absorption from the type-II quantum wells, and efficiently supply carries into these wells by ambipolar diffusion. These type-II integrated absorber lasers exhibit high quantum efficiency and high characteristic temperature associated with lasing threshold.