Kink-free high-fiber-coupled-power 0.98-µm narrow-beam lasers

It is well recognized that 0.98-μm lasers are promising pump sources for Er-doped fiber amplifiers (EDFAs). This application requires a narrow vertical beam divergence and stable lateral mode operation to obtain high coupled power into single-mode fibers. Recently, a fiber-coupled power of 130 mW has been reported in 0.98-μm InGaAs lasers.1