Stable longitudinal-mode InGaAsP/InP internal-reflection-interference laser

An InGaAsP/InP 1.3 μm, buried-crescent internal-reflection-interference (BC-IRI) laser has been developed. Interference is caused by internal reflections from the two faces of the InP notch built in the n-InGaAsP waveguide channel. In the best diode, threshold current was 25 mA, and the temperature variation of the lasing wavelength was 0.75 Å/°C. Mode hopping was not observed in the temperature range from 15 to 45°C, and stable single-mode operation at an injection level more than four times the threshold current was also confirmed. Furthermore, dynamic single-mode operation was obtained at modulation frequencies up to 1 GHz.