High reliability 980-nm pump lasers for Er amplifiers

The erbium-doped fiber amplifier (EDFA) has a profound impact on fiber optic transmission systems in telecommunications as well as cable television. The EDFA can employ pump laser diodes (pumps) at 980 nm or 1480 nm. Due to their fundamental performance advantages in noise figure and useful optical bandwidth 980 nm pumps have been preferred in all applications with the exception of submarine systems that have overriding reliability requirements. The 980-nm laser diode has established itself in countless applications as the prime pump for terrestrial EDFAs (digital and analog) with moderate saturated gain in the last few years. We believe that the tremendous learning will lead this pump chip to play an eminent role in the next few years in submarine applications, high saturated gain EDFAs and cladding pumped fiber lasers.