1.3 MU-M HIGH-PERFORMANCE FS-BH LASER-DIODES WITH WAVE-GUIDE LENS FOROPTICAL ACCESS NETWORK

Narrow-beam and low threshold current characteristics have been realiz ed for a 1.3 mu m FS-BH (Facet Selective growth Buried Heterostructure ) laser diode monolithically integrated with a tapered waveguide lens by a selective area epitaxial growth technique. The beam divergences i n the perpendicular and horizontal directions have been reduced down t o about 12 degrees. By the introduction of the strained quantum well s tructure and the optimized cavity structure, the threshold current has been kept as low as 6 mA which is comparable to the conventional Fabr y-Perot laser diodes. Even at high temperature as high as 85 degrees C , the threshold current and the operation current (P=10 mW) have been suppressed to as low as 23 mA and 63 mA, respectively. Furthermore err or-floor-free characteristics for 622 Mbps-50 km transmission have bee n confirmed under severe optical feedback condition.