InGaAsP/InP distributed feedback buried heterostructure lasers with both facets cleaved structure

Feasibilities of InGaAsP/InP distributed feedback buried heterostructure lasers in the 1.3 and 1.5 μm wavelength regions with two cleaved facets are shown. Theoretical and experimental examinations show that the kL values ranging between 1 and 2 are sufficient for high-performance operation with the stable single longitudinal mode in a temperature range wider than 100 degrees. Distribution of lasing characteristics is investigated for 140 randomly chosen LD´s from two wafers. Approximately 65 percent of the devices are found to be operable in the single longitudinal mode. A CW single longitudinal mode operation power of 20 mW at 25°C for a 1.5 μm device, and that of 40 mW (60 mW with AR coating) at 25°C for a 1.3 μm device with low threshold current are achieved. These characteristics are attained by both first- and second-order grating devices fabricated by the PH3addition LPE technique. The results of the aging test at 70°C and 110 mA in the automatic current control condition are also presented.