Long-lived high-power GaAlAs DH laser diodes at 70°C

Abstract

Long-lived laser diodes are needed for an optical communication system. Hartman et al.1 performed the aging test, using 100 laser diodes, and reported a median lifetime of 4500 h at 70°C. Recently, Fujiwara et al.1 reported that the deterioration of In bonding solder during aging decreases the lifetime of laser diodes, and they have developed a bonding solder of Au alloy to increase the lifetime. In these reports, the optical power was at the low level of 5 mW/facet. Laser diodes rapidly degrade according to the increase in the optical power.3 Facet degradation is dominant for high-power operation. We have obtained long-lived laser diodes for high-power operation using the facet coating, and here we examine the relation between the lifetime and the optical power.