High-power AlGaInAs strained multiquantum welllasers operating at 1.52 µm

1.75 W CW power in AlGaInAs/InP strained QW lasers is demonstrated. Room temperature threshold current densities are 410 A/cm2, and the characteristic temperature is 69 K. The variation in the external differential efficiency with cavity length and temperature reveal the optimum length and show how nonradiative recombination mechanisms limit the performance.