InGaAsP/InP DFB laser array monolithically integrated with MMI combiner and SOA

The monolithic integrated of four channel 1.55- μm range InGaAsP/InP distributed feedback lasers with a 4 × 1 multimode interference (MMI) optical combiner and semiconductor optical amplifier (SOA) using varied width ridge method, butt-joint technique and holographic exposure is proposed and demonstrated. The average output power and the threshold current are 1.8mW and 35mA, respectively, when the injection current of SOA is 100mA, with over 40-dB side mode suppression ratio (SMSR). The lasing wavelength is 1.55-μm range and 40dB sidemode suppression ratio (SMSR) is obtained. The four channels can operated separately or simultaneously.