STRAINED-LAYER MULTI-QUANTUM-WELL LASER-DIODE FOR OPTICAL-FIBER TRANSMISSION-SYSTEMS

A 1.48-mu m high-power laser diode for pumping an optical fiber amplifier and a low distortion 1.3-mu m distributed feedback (DFB) laser for an optical CATV transmission system were developed using a compressively strained layer multi-quantum-well (MQW) structure. A high external quantum efficiency and comparatively high characteristic temperature were obtained in optimized InGaAs wells, and an output power as high as 210 mW at 1.48 mu m was demonstrated. Using highly strained InGaAsP wells (strain= 1%), a high external quantum efficiency and low threshold current were obtained at 1.3 mu m. A fabricated 1.3-mu m DFB laser module for 78-channel CATV transmission demonstrated an extremely tow distortion of -60 dBc even at a high output power of 13 mW.