Introduction
Compactness and minimal power consumption at low cost are crucial requirements for successful implementation of pump modules in metro systems. A new generation of ridge-waveguide 980-nm pump laser diodes has been developed suitable for such purposes[1], [2] showing high insensitivity with temperature. excellent wavelength stabilization with fiber Bragg gratings (FBG) and high reliability. Our packaged generation-6 (G06) laser diodes demonstrate wavelength stabilized operation over 135 K without active cooling. with still 110mW of wavelength stabilized ex-fiber power at 120°C [1]. At a temperature of 70°C which is a practical upper limit for central office environments, powers in excess of200 m\V are obtained. Elimination of the bulky thermo-electric cooler (TEC) does not only significantly reduce power consumption of the pump module, but also enables smaller footprint packaging schemes targeting truly low cost erbium doped fiber amplifiers. In the following the key aspects of 980 nm metro pumps based on our G06 laser will be addressed. specifically performance trade-offs power consumption, cost, size and reliability.