SIMULTANEOUS CW OPERATION OF 5-WAVELENGTH INTEGRATED GAINASP-INP DFB LASER ARRAY WITH 50-A LASING WAVELENGTH SEPARATION

The simultaneous CW operation of a 5-wavelength integrated GaInAsP/InP DFB laser array has been realized. The average lasing wavelength separation was 49 A, which was in very good agreement with the designed value. Threshold currents were 57 to 75 mA and differential quantum efficiencies were 11 to 21%. A simultaneous CW operation was obtained at up to 40 degree C with each stable single longitudinal mode. It was found that the threshold current was almost independent of wavelength within a range of 500 A on the long wavelength side of the spontaneous emission peak and could be reduced to as little as 20 mA by fabricating deep, uniform gratings and by increasing the crystal homogeneity of the wafer.