703-nm InGaAsP Quantum-Well Ridge-Waveguide Lasers

An InGaAsP/AlGalnP quantum-well (QW) laser emitting at 703 nm on a GaAs substrate was demonstrated. Although quaternary InGaAsP is reported to have an immiscible region, compressively strained, thin InGaAsP was successfully grown on a GaAs substrate as an active layer. The ridge-waveguide structure of the laser has a 2-μm stripe and achieves extremely low operating current at a 40-mW CW from 20 to 80°C with a characteristic temperature of 151 K. These InGaAsP QW lasers have been operating for over 640 hours during a 40-mW-constant-power CW life test at 40°C. This laser diode is suitable as a light source for spectroscopic measurement due to its single longitudinal mode and stable fundamental lateral transverse mode.