A 970-nm Strained-Layer InGaAs/GaAlAs Quantum Well Laser for Pumping ER-doped Optical Fiber Amplifier.

We report the performance of a 970-nm strained-layer InGaAs/GaAlAs quantum well laser and its application for pumping Er-doped optical fiber amplifiers. The laser was grown by molecular beam epitaxy and has three In sub (020 Ga sub (08) AsGaAs quantum wells. For a 5 micron wide and 400 micron long ridge- waveguide laser, a CW threshold current of 20 mA and an external quantum efficiency of 0.28 mW/mA per facet were obtained. Maximum output power exceeds 32 mW/facet. With anti-reflection coating, even higher external quantum efficiency (0.40mW/mA) was achieved, and more than 20 mW of power was coupled into a single mode fiber. Preliminary experiments of pumping the Er-doped fiber amplifier gave 15dB of gain at 1.555 micron for a pump power of 14 mW into the Er fiber.