Low threshold CW operation ofGaInP/AlGaInP DFB lasers at 680 nm

Abstract
Continuous wave operation of GaInP/AlGaInP DFB lasers at room temperature is reported. The DFB lasers in ridge waveguide geometry show stable singlemode emission with a sidemode suppression > 30 dB and a threshold current of 25.9 mA at 20°C. Singlemode operation could be achieved for a large temperature range between –10 and 40°C. Even for 40°C the threshold current remains below 50 mA.