InP/AlGaInP quantum dot laser emitting at 638 nm

We demonstrate electrically pumped laser light emission in the visible (red) spectral range using self-assembled InP quantum dots embedded in an (AlxGa1−x)0.51In0.49P(AlxGa1−x)0.51In0.49P matrix lattice matched to GaAs. The structures were fabricated by metal-organic vapor-phase epitaxy. The use of different aluminum contents in the barrier layers leads to strong emission wavelength shifts due to Al incorporation into the active InP quantum dots, resulting in electrically pulsed laser operation at 661 and 638 nm at room temperature. The devices exhibit low threshold current densities as low as 300 A/cm2. Optical output power of more than 200 mW per facet at room temperature is demonstrated.